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Sonntag, 27. April 2014 - 10:26 Uhr

Astronomie - Rosas 4,5 Milliarden Jahre alter Meteorit

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Eine 94-jährige Spanierin übergibt der Forschung einen Meteoriten, den sie als Mädchen im Alter von elf Jahren gefunden hatte. Das hat den Wissenschaftsrat auf den Plan gerufen. Er bittet um mehr Zusammenarbeit.

Spanien hat eine neue Verwandte. Seit ein paar Tagen spricht das Land von Tante Rosa. Die 94-jährige Dame aus dem nordkastilischen Dorf Ardón gelangte jüngst wegen eines Vorfalls zu Ruhm, der sich vor 83 Jahren zugetragen hat. Damals war die Elfjährige auf dem Weg zur Bodega des Dorfes, um ihrem Onkel die Vesper zu bringen.

Plötzlich hörte sie Donnergrollen. Als sie aufblickte, sah sie ein rauchendes Steinchen vom Himmel fallen. Sie hob es auf und verbrannte sich dabei fast die Hand. Die Aufregung war gross. «Der Priester sagte meiner Tante schliesslich, sie habe einen Meteoriten gefunden und sie solle ihn gut aufbewahren», erzählte ihr Neffe jüngst spanischen Medien. Das Mädchen befolgte den Rat und verwahrte das fünfeinhalb Gramm schwere Steinchen mehr als 80 Jahre lang in ihrem Schmuckkästchen.

 
 
Dem naturwissenschaftlichen Interesse des Neffen ist es zu verdanken, dass Tante Rosas Geheimnis inzwischen gelüftet ist. Er übergab den Stein vergangenes Jahr dem spanischen Forschungsrat CSIC. Dieser hat ihn untersucht und nun öffentlich vorgestellt. «Ardón», so wurde der dunkle, poröse Stein getauft, ist ein sogenannter Gewöhnlicher Chondrit der Gruppe L6, dessen Alter auf rund 4,5 Milliarden Jahre geschätzt wurde.

Der Chondrit stamme aus der Zeit, in der sich die ersten Planeten des Sonnensystems gebildet hätten. Das Steinchen sei Teil des Asteroiden (1272) Gefion, der sich aus dem Asteroidengürtel zwischen Mars und Jupiter gelöst habe und rund 26 Millionen Jahre später, genau gesagt am 9. Juli des Jahres 1931, in die Erdatmosphäre eintrat. Wie die Forscher erklärten, ist er dabei in Hunderte von Fragmenten zerbrochen. Eines davon fiel der elfjährigen Rosa vor die Füsse.

Eine Scheibe dieses Fragments soll nun im Madrider Wissenschaftsmuseum die Geschichte des Meteoriten erzählen. Der Rest gehört wieder der Finderin. Statistisch müsste seit dem Jahr 1931 jedes Jahr ein Meteorit von rund einem Kilo Gewicht über Spanien niedergegangen sein, registriert wurden aber lediglich deren drei in den folgenden Jahren: 1947, 2004 und 2007. Die Wissenschafter forderten nun die Bevölkerung auf, Funde zu melden und enger mit der Forschung zusammenzuarbeiten. Viele Meteoriten werden nämlich über Ebay an Privatsammler verkauft. Sie gehören aber eigentlich zum spanischen Naturerbe und dürfen nach einem Gesetz vom Jahr 2007 weder veräussert noch ausser Landes gebracht werden.

Quelle: Neue Zürcher Zeitung


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Samstag, 26. April 2014 - 16:30 Uhr

Raumfahrt - Kanada storniert Start von M3M Satelliten mit Sojus-Rakete

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Ukraine Crisis Scuttles Canadian Satellite Launch on Soyuz

Russia's actions in Ukraine have prompted the Canadian government to forego a planned launch of its M3M satellite atop a Soyuz rocket this summer, Canadian satellite manufacturer COM DEV International announced April 24.

The satellite, a small maritime ship-tracking spacecraft, was previously scheduled to launch as a secondary payload on Soyuz from the Baikonur Cosmodrome, Kazakhstan, in June.

"Recognizing the current events in the Ukraine, we had been engaged in discussions with the Government of Canada with respect to a potential delay of the launch of M3M, and plans to mitigate the impact of any delay," said COM DEV CEO Mike Pley. "We are confident that the mitigations will be in place prior to the originally planned M3M in-service date of September 2014."

Built by COM DEV under contract to the Canadian Space Agency/Public Works Government Services Canada and the Department of National Defense, M3M is also subject to a commercial data sharing license with exactEarth, in which COM DEV is majority owner.

“Both COM DEV and exactEarth made significant investments in the development of the satellite, and in upgrading its capabilities,” according to the Aprl 24 statement, which said the Canadian Space Agency has indicated it will support the company's efforts to secure a new launch.

In March, as Moscow consolidated its hold on Crimea, the U.S. State Department suspended approval of defense exports to Russia, a move that could prevent the launch of U.S. commercial communications satellites on Russian rockets.

“State will continue this practice until further notice,” the department’s Directorate of Defense Trade Controls (DDTC) said in a March 27 announcement on its website.

DDTC export licenses are required to launch U.S. satellites —or foreign-built satellites containing U.S. components controlled by International Traffic in Arms Regulations (ITAR)—on Russian launch vehicles.

If the ban on issuing such licenses remains in effect, the impact would be felt most immediately by International Launch Services (ILS) of Reston, Va., and Sea Launch International of Nyon, Switzerland; ILS markets launches on Russian Proton vehicles, while Sea Launch manages flights on Russia’s Zenit launcher.

However, launch industry sources said the hold could potentially affect Soyuz launches from Baikonur Cosmodrome in Kazakhstan and Europe’s Guiana Space Center in French Guiana, where launch consortium Arianespace manages commercial missions of the four-stage, medium-lift Soyuz.

Quelle: Aviation Week

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Russian sanctions have killed Canadian satellite launch

M3MSat is a tele-detection satellite, and its mission is to demonstrate and test the technology of three instruments.

Photograph by: Handout photo , Canadian Space Agency

The Conservative government’s hard line on sanctions against Russia has scuttled the launch of a key Canadian military satellite that was to be put into orbit by a Russian rocket.

Officials with the Canadian Space Agency and the spacecraft’s builder, Com Dev, are now trying to find another country or private company willing to send the surveillance satellite into space.

The move to cancel the June 19 launch of the satellite comes as the Canadian government continues with sanctions against Russia over the situation in Ukraine.

Canada has imposed economic penalties on a number of Russian companies and individuals and cancelled a planned military exercise with the Russian air force. It also expelled an attaché from the embassy in Ottawa.

On Tuesday, Russia expelled a Canadian diplomat in Moscow, labelling him a spy.

Com Dev issued a statement Thursday night that it would not proceed with the launch of the spacecraft known as M3MSat.

“Recognizing the current events in the Ukraine, we had been engaged in discussions with the Government of Canada with respect to a potential delay of the launch of M3M, and plans to mitigate the impact of any delay,” said Mike Pley, chief executive officer of Com Dev. “We are confident that the mitigations will be in place prior to the originally planned M3M in-service date of September 2014.”

Canadian Space Agency spokeswoman Maya-Olivia Eyssen said the satellite was to have been launched from Russia’s facilities in Kazakhstan. “The Government of Canada is working with Com Dev to find an appropriate launch solution,” she noted.

M3MSat will provide maritime surveillance and work in conjunction with another Canadian spacecraft, Radarsat-2.

The Department of National Defence’s science agency is supporting M3MSat, with help from the CSA. The spacecraft is outfitted with sophisticated technology to allow it to track digital signals transmitted by ships.

That would make it possible to identify and record marine traffic, know vessels’ direction and cruising speed and ensure that they navigate legally and safely in Canadian waters, according to the DND and the space agency.

The launch of another two smaller Canadian satellites to be sent aloft on the same rocket have also been scuttled. There are no details on how those spacecraft will be put in orbit.

In its statement, Com Dev noted it was the Canadian government that decided not to proceed with the planned launch.

DND declined to comment, referring all questions to the CSA.

Russia has indicated it is more than willing to launch the Canadian satellites, say sources.

The Canadian government’s sanctions against Russia could put Canada’s space industry in a bind as there are a limited number of nations and private companies capable of launching satellites.

Walt Natynczyk, the head of the Canadian Space Agency, said in mid-April that sanctions against Russia would not affect operations on the International Space Station. Canada would continue to work with Russia and the other nations involved in the station, he added.

Co-operation on other space projects, however, will be decided on a case-by-case basis, the former general noted.

Com Dev built and tested the spacecraft at its facilities in Cambridge, Ont., and Ottawa.

It is unclear whether the Canadian government will cover any extra costs that might be incurred in finding a country or firm willing to launch the spacecraft at such short notice.

“Com Dev has received an indication that the Canadian Space Agency will support Com Dev’s efforts to secure a new launch,” the company statement added.

Quelle: The Ottawa Citizen


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Samstag, 26. April 2014 - 16:14 Uhr

Raumfahrt - Mutiges Phoenix Satelliten-Recycling-Projekt des US-Militärs geht in neue Phase

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DARPA's Proposed Phoenix satellite tender nears a satellite in orbit.

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An ambitious Pentagon effort to repair and recycle satellites in Earth orbit has moved one step closer to reality.

The Defense Advanced Research Projects Agency (DARPA) awarded prime contracts to eight companies earlier this month, advancing its Phoenix satellite-servicing program to Phase 2 of development.

"Phase 1 not only showed the feasibility of our robotic tools and assembly techniques, but also validated the concept that we could build new satellites on orbit by physically aggregating satlets in space," DARPA program manager David Barnhart said in a statement. "These successes could eventually lead to the revolutionary ability to create new, truly scalable space systems on orbit at a fraction of current costs."

DARPA hopes Phoenix develops tools and capabilities that will allow satellites to be inspected, serviced, upgraded and assembled on orbit, extending the lifespan of existing space assets and significantly reducing the cost of future satellites.

These goals apply especially to hardware in geosynchronous Earth orbit (GEO), which lies about 22,000 miles (35,406 kilometers) above the planet's surface. Satellites way up there are pretty much out of reach with current technology, officials said.

Researchers will concentrate on three main areas during Phoenix's Phase 2. First, they'll continue to develop advanced space robotics technologies that would allow a future "Servicer/Tender" spacecraft to assemble, repair and refuel satellites in GEO.

Engineers will also work on developing "satlet" architecture — a system of many small, independent modules that can be joined up in various ways to accomplish a broad range of mission objectives. The 15-lb. (7 kilograms) modules could be produced on an assembly line and outfitted with different payloads easily and quickly, DARPA officials said.

Phase 2 will also advance research into a cost-cutting Payload Orbital Delivery (POD) system, which would allow a variety of payloads, satlets and other gear to hitch rides to space aboard commercial communications satellites.

"Individually or together, these technologies could help enable not just Phoenix’s original concept of re-use, but a broad class of other robotically enabled missions at GEO as well," Barnhart said. "They could help satellites reach new or proper orbits, inspect satellites as part of routine maintenance or troubleshooting efforts, repair or replace worn-out components or add or upgrade capabilities."

The eight companies receiving Phase 2 prime contracts are Busek; Energid Inc.; Honeybee Robotics; MacDonald, Dettwiler and Associates Ltd.-Canada; MacDonald, Dettwiler and Associates Ltd.-U.S.; NovaWurks; Oceaneering Inc.; and Space Systems/Loral.

Quelle: SC


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Samstag, 26. April 2014 - 15:42 Uhr

UFO-Forschung - UFO-Absturz bei Roswell 1947 ? Teil-12

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Klassifizierte Dokumente und Roswell

James Moseley recently sent me a letter that he described as “an exclusive” concerning the recovered aliens and saucer at Roswell. It was a printed e-mail that Karl Pflock had sent him with some notes written on it. The content of the e-mail was another classified document stating that there was no physical evidence to examine from crashed flying saucers. In the late 1990s, these kinds of documents were presented by Phil Klass, Robert Todd, Kent Jeffrey, and Karl Pflock as evidence against the idea that there ever was a crashed spaceship at Roswell.
All of these documents were important items that needed to be considered. In a 1998 Fortean Times article, Karl stated,
It is important to understand that the documents in question were written decades before the passage of the US Freedom of Information Act in 1975 made it possible to peer behind the wall of American official secrecy. They were created by those whose job it was to crack the flying saucer mystery, who wrote and spoke, certain no unauthorized person would ever be privy to their words. They were the products of, and addressed to, men who had fought World War II and were fighting the Cold War, men used to doing their duty with little fear of being second-guessed, who sat in the highest ranks of American intelligence and official science. They had no qualms about being forthright with each other inside the comfortable precincts of security classifications and Pentagon conference rooms. In fact, their responsibilities demanded it.1
These classified documents reflect the actual knowledge of these gentlemen at the time they were writing them. Not once, in all of the documentation released to date, is there any mention of a spaceship or saucer being actually recovered and studied by the USAF!

1947: Roswell and then...?
In July 1947, the Roswell event occurred. If we are to believe the present mythology, hundreds, if not thousands, of airmen and civilians were quite aware of what happened in New Mexico that week. However, for some reason, the official record is barren when it comes to this momentous event. In fact, they seem to point towards a more terrestrial source.
The official record of the Roswell incident pretty much relies on news reports, unit histories, and an FBI telex. The morning reports/history of the Roswell Army Air Field/509th bomb group indicate no unusual activity despite hundreds of airmen supposedly being deployed throughout New Mexico to retrieve and transport a crashed saucer.
The first classified document (SECRET) of interest is the infamous Twining memo of September 23, 1947. While the document is mentioned in the three books The Roswell Incident, UFO Crash at Roswell, and Crash at Corona, they focus only on the line, a. The phenomenon is something real and not visionary or fictitious2. Strangely (or not so strangely), the following section is missing:
h. Due consideration must be given the following:-
(1) The possibility that these objects are of domestic origin - the product of some high security project not known to AC/AS-2 or this Command.
(2) The lack of physical evidence in the shape of crash recovered exhibits which would undeniably prove the existence of these subjects.
(3) The possibility that some foreign nation has a form of propulsion possibly nuclear, which is outside of our domestic knowledge.3 (my emphasis in bold)
Was it left out by accident or did h(2) scare the writers so much that they did not want their readers to see it?
Shortly after the Twining memo was released, there was another document about UFOs generated by General Schulgen on 30 October 1947 (Classified SECRET). Its subject line is “Intelligence Requirements on Flying Saucer Type Aircraft” and speculates about what type of vehicle could be involved in these “Flying saucer” reports. Most important is this line:
For the purpose of analysis and evaluation of the so-called “flying saucer” phenomenon, the object sighted is being assumed to be a manned aircraft, of Russian origin, and based on the perspective thinking and actual accomplishments of the Germans.4
If the AF had recovered an actual flying saucer, why would they waste the time with this type of report and analysis?


1948: Sign up ahead!

At the end of 1947, project Sign was created in an effort to collect and evaluate UFO sightings. They were to determine what the causes of these UFO reports were and work with various agencies to accomplish this task. While there is the document often referred to as the “Estimate of the situation” (which suggested the possibility that UFOs COULD be extraterrestrial but did not mention Roswell) described by Ruppelt, nobody has ever seen the document or any document that suggested it really existed as described. However, there are other documents from the days of Project SIGN that demonstrate they knew nothing about the USAF having an actual crashed disc in their inventory.
During a SECRET briefing to the Air Force Scientific Advisory Board given on March 17, 1948 (about 8 months after Roswell), Colonel McCoy (Deputy Commanding General Intelligence T-2 at Air Material Command (AMC)) stated,
... I can’t even tell you how much we would give to have one of those crash in an area so that we could recover whatever they are.5
Why would he state this, if he knew they had captured a crashed spaceship? If he knew they had such a device, he would not bother mentioning it if it were highly classified. However, he would not be so emphatic that they would like to recover one. Either he was “out of the loop” or the crashed saucer did not happen.In October 1948, McCoy sent off a series of letters to all the intelligence agencies (CIA, Navy, and Army) asking for help. McCoy states in all of these letters:
This Headquarters is currently engaged in an intelligence investigation of all reported unidentified aerial phenomena. To date, no concrete evidence as to the exact identity of any of the reported objects has been received. Similarly, the origin of the so-called ‘flying discs’ remains obscure. The possibility exists that some of the sighted objects are of domestic origin... Your cooperation... might greatly assist in identifying our own domestic developments from possible inimical foreign achievements.6
The key words were that no concrete evidence was available. Once again, we have McCoy confirming that he had absolutely no knowledge of an alien spaceship crash. McCoy’s letters were probably due to him feeling some heat from above about Sign’s apparent lack of progress on the UFO problem.
On November 3rd,1948, Major General Cabell, the head of intelligence himself, wrote to Sign (classified SECRET) requesting some results after one year of work:
The conclusion appears inescapable that some type of flying object has been observed. Identification and the origin of these objects is not discernible to this Headquarters. It is imperative, therefore, that efforts to determine whether these objects are of domestic or foreign origin must be increased until conclusive evidence is obtained. The needs of national defense require such evidence in order that appropriate countermeasures may be taken.7
McCoy would respond on the 8th with another secret memo. There he outlined everything that they conclude up to that point. One item mentioned is this:
The possibility that the reported objects are vehicles from another planet has not been ignored. However, tangible evidence to support conclusions about such a possibility are completely lacking…. 8 Another item mentioned is clear cut: 10. In view of the above, the following conclusions are drawn:
a. In the majority of cases reported, observers have actually sighted some type of flying object which they cannot classify as an aircraft within the limits of their personal experience.
b. There is as yet no conclusive proof that unidentified flying objects, other than those which are known to be balloons, are real aircraft.
c. Although it is obvious that some types of flying objects have been sighted, the exact nature of those objects cannot be established until physical evidence, such as that which would result from a crash, has been obtained.9 (my emphasis in bold)
Once again, McCoy is stating that there is no physical evidence for them to examine and that no crashes have yet been recovered.
All of this collection of data culminated in what became known as the Air intelligence report #203 (Appendix “A” was classified TOP SECRET). It concluded that these flying saucers, if they were real craft, could be one of two things. The first would be domestic devices like experimental craft. The other was the idea suggested by General Schulgen’s memo a year before. They suspected they were Soviet aircraft based on German designs captured at the end of the war. There was also concern that the propulsion plant might be atomic in nature. Additionally, appendix C of the study listed various UFO reports. Roswell was not one of them.
In all of these letters and reports that have been uncovered over the years, one major theme recurs. The USAF was more concerned that these reports were of Soviet aircraft that were revolutionary in design and not concerned they indicated a potential threat from outside the Earth.


1949-1951 Does anybody care?
In 1949, Project Sign was changed to project Grudge. While UFOlogists suggest this as a change in attitude to go with the name, there still seemed to be a desire to get down to the UFO problem. In the Top Secret USAF director of intelligence’s report to the Joint Intelligence Committee on Unidentified aerial objects on 27 April 1949, we read:
Inasmuch as various surmises have been advanced that some of the reported observations may have represented “space ships” or satellite vehicles, a special study has been initiated with the Rand Corporation, under the Rand Project, to provide an analysis from this standpoint and also to provide fundamental information, pertaining to the basic design and performance characteristics that might distinguish a possible “space ship.” Rand Corporation has also informed AMC that their analysis of all incidents leads them to the conclusion that there is nothing in any reported incidents which would go against a rational explanation. 10
Again, there is no mention of Roswell and the USAF commissioned RAND to look into the idea that these could be alien spaceships! If they had already recovered one, why spend the money on something they already knew?


1952-1954 Dazed in Dayton
General W. M. Garland, who would eventually take over at the head of ATIC, wrote a memo in early 1952 that addressed the UFO question again. As was the case in 1948, General Garland was concerned about these flying saucer reports being observations of Soviet aircraft. The question remained why did the USAF have a fascination with the threat of Soviet aircraft being the source of these UFOs, when they already knew that UFOs were alien spaceships?
Bluebook spent most of 1952 chasing hundreds of UFO reports. By the end of the year, the CIA had become involved in the UFO question. They commissioned a blue ribbon panel of scientists to evaluate the UFO problem in January 1953. This meeting was classified secret and is referred to as the Robertson Panel. Not once was a spaceship crash mentioned. Additionally, if they already knew that flying saucers were alien spaceships, why would they bother to waste these scientists time looking at UFO reports?
In 1953, Captain Edward Ruppelt gave a SECRET briefing to the Air Defense Command. In this briefing, Ruppelt stated thefollowing regarding the possibility that UFOs were alien spaceships:
However, there is no, and I want to emphasize and repeat the word “No” evidence of this in any report the Air Force has received…we have never picked up any “hardware.” By that we mean any pieces, parts, whole articles, or anything that would indicate an unknown material or object. 11
Once again, the crashed spaceship link is missing.


SR14 nixes the crash idea
Project Bluebook’s Special Report Number 14 is considered by some as one of the greatest documents produced about UFOs by the USAF. It was an effort by Battelle scientists to examine all the reports and analyze them scientifically. What did it say about crashed flying saucers?
It is emphasized that there was a complete lack of any valid evidence consisting of physical matter in any case of a reported unidentified aerial object.13
Why would these scientists at Battelle note they had no physical evidence when, according to some, they had all seen the debris at one point and had been trying to reverse engineer it?


The GAO is shutout
In the early 1990’s the Government Accounting Officer (GAO) was asked to look for documents pertaining to the Roswell “crash”. Despite examining the minutes of the National Security Council 1947-8, AMC research and development tiles 1947-50, and HQ Army Air Force message traffic 1947-54, the GAO could find no indication of any documents related to Roswell:
The other government records we reviewed, including those previously withheld from the public because of security classification, and the Air Forces analysis of unidentified flying object (1) sightings from 1946 to 1953 (Project Blue Book Special Report No. 14), did not mention the crash or recovery of an airborne object near Roswell in July 1947. Similarly, executive branch agencies’ response to our letters of inquiry produced no other government records on the Roswell crash…As a final step, we reviewed Air Material Command (Wright Field) records from 1947 to 1950 for evidence of command personnel involvement in this matter. We found no records mentioning the Roswell Crash or the examination by Air Material Command personnel of any debris recovered from the crash. 12
Were all these records that discussed the Roswell crash (which must be numbered in the hundreds/thousands) removed from the face of the earth? Were all the activities of AMC personnel edited to prevent anybody noticing them flying to Roswell and other places to examine the debris? Why isn’t there just a hint that something unusual had transpired? Is it because NOTHING out of the ordinary happened or is it because of the conspiracy has covered its tracks better than any other conspiracy before or since?


Smoke screen or self-deception?
All of these documents mean nothing to UFOlogists. Some have suggested that there was an alternate path of communication and all of this was a smoke screen. They insist that any records of a crash were destroyed or that those documents are so classified that nobody would ever see them. Stanton Friedman stated the government has lied before in the case of the Trinity explosion and the U-2 flight by Gary Powers. What he ignores is that these were all public statements and not classified documents. I am unaware of any classified documents that denied the existence of U-2 overflights or an atomic bomb was not exploded at Trinity. To lie to the public in order to cover-up a secret is one thing. To lie and refrain from mentioning the crash to each other in multiple classified documents is another.
UFOlogists will ignore these documents with the excuse that the great conspiracy required that these officers lie about crashed materials because they feared that someday it might be possible that the general public could see what was written. With that kind of logic, one can dismiss anything that was ever written by just simply stating it is part of the conspiracy.

Quelle: SUNlite 6/2010

 



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Samstag, 26. April 2014 - 11:30 Uhr

Astronomie - Kosmischer Feuerball über ALMA

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This beautiful new image, taken during a time lapse set at the Atacama Large Millimeter/submillimeter Array (ALMA) is another dramatic Ultra High Definition photograph from the ESO Ultra HD Expedition. ALMA, located at 5000 metres above sea level on the remote and empty Chajnantor Plateau in the Chilean Andes, marks the second destination for the four ESO Photo Ambassadors [1] on their 17-day trip. The ambassadors are equipped with state-of-the-art Ultra HD tools to help them capture the true majesty of sights like the one pictured here [2] [3].

Some of the 66 high-precision antennas that comprise ALMA are visible here, with dishes pointed aloft, studying the cold clouds in interstellar space, and peering deep into the past at our mysterious cosmic origins.

The spectacular javelin of light over the ALMA array is a shooting star, slicing through the image in a vivid streak of colours. Emerald green, golden and faint crimson hues blaze brightly as the meteor burns up as it enters the Earth’s atmosphere and makes its fiery voyage across the sky. As the high-speed fireball — which is, in reality, a small grain of rock from interplanetary space — interacts with the atmosphere it heats up, vapourising the surface layers of the meteor, which are left behind in a glowing trail. These trails disappear in just a few seconds, but are captured here at the click of a button.

The brightest star in the constellation of Virgo (The Virgin), known as Spica, and our neighbouring planet Mars glow brightly in the centre of the image — cosmic spectators to this fiery descent as they rise above the horizon.

The Ultra HD Expedition began in Santiago, Chile, on 25 March 2014. This image was taken on the team’s eighth night on the Chajnantor Plateau. They are currently at La Silla Observatory, ESO’s first astronomical installation in Chile, and tomorrow, after one last night, they will finally make the long journey home. Free Ultra HD content gained from this expedition will soon be available online as ESO delivers crisp, breathtaking Ultra HD footage — bringing the Universe closer than ever before. This image was taken by ESO Photo Ambassador and Timelapse Cinematographer Christoph Malin.

Notes

[1] The team is made up of ESO’s videographer Herbert Zodet, and three ESO Photo Ambassadors: Yuri Beletsky, Christoph Malin and Babak Tafreshi. Information on the expedition’s technology partners can be found here, and their blog here.

[2] Equipment includes: Vixen Optics Polarie Star Tracker, Canon® EOS-1D C camera, Stage One Dolly and eMotimo TB3 3-axis motion control camera robot, Angelbird SSD2go, LRTimelapse software. Peli™ Cases, 4K PC workstations from Magic Multimedia, Novoflex QuadroPod system, Intecro batteries and Granite Bay Software.

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Quelle: ESO


2612 Views

Freitag, 25. April 2014 - 22:15 Uhr

Raumfahrt - LADEE im Mondorbit / LADEE Impact+The Legacy Lives On! - Update

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9.10.2013

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LADEE Trajectory Update 10-9-13: LOI-2 nominal

The LADEE Lunar Orbit Insertion burn 2 (LOI-2) executed as planned this morning at 3:38 PDT, placing LADEE into a 4 hr orbit.  Things move much faster now for the spacecraft, and the Moon is looking a lot bigger. We originally captured with a periselene altitude near 560 km but our periselene has now been lowered to an altitude of ~235 km by Earth perturbations in the Post-LOI-1 24 hr orbit.  The planned periselene of the commissioning orbit was 250 km, however the small (

LOI-2 lowered our apogee down to ~2200 (we’ll have to wait for some more tracking to verify that exactly).

From our pre-LOI2 planning, things should now (9 Oct 2013 13:00 UTC)  look like this:

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Quelle: astrogators guide

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Update: 24.10.2013

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A Successful Moon Shot for Laser Communications
A test of high-bandwidth optical communications from lunar orbiter to earth stations succeeds.
There was no “Mr. Watson—come here—I want to see you” moment. But a pioneering space-based optical communications test has proven a big success. And that means optical systems stand a higher chance of not only dominating future space data transmissions (with radio systems serving as a backup) but of enabling new satellite networks that would boost the capacity of the terrestrial Internet.
A planned test of the Lunar Laser Communications Demonstration (see “NASA Moonshot Will Test Laser Communications”) aboard a probe in lunar orbit is working just as planned, delivering six times greater download speeds compared to the fastest radio system used for moon communications, Don Boroson, the researcher at MIT’s Lincoln Lab who led the project, says.  “We have successfully hit all our marks—all the downlink rates up to 622 Mbps [and] our two uplink rates up to 20 Mbps.”
One of the toughest parts of the task: aligning ground telescopes to continually see the incoming infrared laser beam dispatched from a probe whizzing around the moon. This “signal acquisition”  was “fast and reliable,” he added.  His team even transmitted high-definition video of “shuttle launches, space station antics, and Earth images. Also, some little videos we took of ourselves in the operations center.”
Ground-based detectors were set up in California, New Mexico, and on one of the Canary Islands. The big trouble spot for sending optical signals through the air is that they can be blocked by clouds. Still, in the future, networks of satellites could transmit data among each other and then to ground stations in various places, giving a bandwidth boost to the ground-based fiber network.
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Quelle: MIT-Technology-Review

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Update: 29.10.2013

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Historic Demonstration Proves Laser Communication Possible

In the early morning hours of Oct. 18, NASA’s Lunar Laser Communication Demonstration (LLCD) made history, transmitting data from lunar orbit to Earth at a rate of 622 Megabits-per-second (Mbps). That download rate is more than six times faster than previous state-of-the-art radio systems flown to the moon.

“It was amazing how quickly we were able to acquire the first signals, especially from such a distance,” said Don Cornwell, LLCD manager. “I attribute this success to the great work accomplished over the years by the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL) and their partnership with NASA.”
LLCD is being flown aboard the Lunar Atmosphere and Dust Environment Explorer satellite known as LADEE, currently orbiting the moon. LADEE is a 100-day robotic mission designed, built, tested and operated by a team from NASA’s Ames Research Center in Moffett Field, Calif. Its primary science mission is to investigate the tenuous and exotic atmosphere that exists around the moon.
LADEE, with LLCD onboard, reached lunar orbit 30 days after launch from NASA’s Wallops Flight Facility on Wallops Island, Va., on Sept. 6.  During the trip, the LADEE team provided an opportunity for LLCD to make post-flight calibrations of its pointing knowledge. “Being able to make those calibrations allowed us to lock onto our signal almost instantaneously when we turned on the laser at the moon,” said Cornwell. “A critical part of laser communication is being able to point the narrow laser beam at a very small target over a great distance.”
LLCD not only demonstrated a record-breaking download rate but also an error-free data upload rate of 20 Mbps. The laser beam was transmitted the 239,000 miles from the primary ground station at NASA’s White Sands Complex in Las Cruces N.M., to the LADEE spacecraft in lunar orbit. This breakthrough technology has a laser-based space terminal that is half the weight of a comparable radio-based terminal while using 25 percent less power. 
These first tests of the month-long demonstration have included the successful LLCD transmission, by pulsed laser beam, of two simultaneous channels carrying high-definition video streams to and from the moon.  Proving the capability to communicate with multiple locations, LLCD successfully transmitted its beam several times to NASA’s Jet Propulsion Laboratory’s Optical Communications Telescope Laboratory in California. Soon testing will also include transmissions originating from the European Space Agency’s (ESA) Optical Ground Station in Tenerife, Spain.
The tests also confirmed LLCD’s capability of providing continuous measurements of the distance from the Earth to the LADEE spacecraft with an unprecedented accuracy of less than half an inch. “We hope this demonstration validates the capabilities and builds confidence in laser communication technology for consideration on future missions,” said Cornwell.
LLCD has also transmitted large data files from the LADEE spacecraft computer to Earth. “These first results have far exceeded our expectation,” said Cornwell. “Just imagine the ability to transmit huge amounts of data that would take days in a matter of minutes. We believe laser-based communications is the next paradigm shift in future space communications.”
Future testing will include how well the system operates in optically stressed conditions such as daytime (all operations have been at night), full moon verses new moon, and different pointing positions for the ground terminals. “These series of tests will allow us to sample different conditions to demonstrate the flexibility of the technology,” said Cornwell.
The LLCD system was designed, built and being operated by the MIT/LL team in Lexington, Mass. LLCD is managed by NASA’s Goddard Space Flight Center in Greenbelt, Md. The LADEE spacecraft was built and operated by NASA’s Ames Research Center in Moffett Field, Calif. Additional ground terminals have been provided by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and ESA in Darmstadt, Germany.
NASA’s laser communications between LLCD and Earth ground stations is the longest two-way laser communication ever demonstrated. It is the first step and part of the agency’s Technology Demonstration Missions Program, which is working to develop crosscutting technology capable of operating in the rigors of space.
The Laser Communications Relay Demonstration (LCRD) is the follow-on mission, scheduled for launch in 2017. Also managed at Goddard, LCRD will demonstrate laser relay communications capabilities for Earth-orbiting satellites continuously over a period of two to five years.
"LLCD is the first step on our roadmap toward building the next generation of space communication capability," said Badri Younes, NASA's deputy associate administrator for space communications and navigation (SCaN) in Washington, which sponsored LLCD. "We are encouraged by the results of the demonstration to this point, and we are confident we are on the right path to introduce this new capability into operational service soon."
Quelle: NASA
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Update: 2.11.2013
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Mondmission Laserstrahlen Daten erreichen ESA Station
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Focal spot: laser light seen by infrared camera
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ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

The Lunar Atmosphere and Dust Environment Explorer, or LADEE, was launched on 7 September and arrived in orbit around the Moon in October. In addition to probing the Moon’s environment, it’s also carrying a new laser terminal.

This new approach promises data speeds far superior to traditional radio waves used today by satellites and ground stations, including the Agency’s Estrack network.

ESA’s Optical Ground Station in Spain’s Canary Islands was upgraded with an advanced laser terminal developed in Switzerland and Denmark that can communicate with LADEE using highly focused beams.

“We acquired the first signals from LADEE on 26 October, and since then, we’ve had a series of optical uplinks and downlinks providing extremely fast laser communications,” says Zoran Sodnik, ESA’s project manager for the laser effort.

“We’ve already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection.”

The contact with Tenerife came just days after LADEE made history on 18 October in the first-ever laser transmission from lunar orbit, picked up by a NASA station at White Sands, New Mexico, USA. The craft is also transmitting to a third station, at NASA’s Jet Propulsion Laboratory in California.

Laser communications at near-infrared wavelengths may be the way of the future when it comes to downloading massive amounts of data from spacecraft orbiting Earth, Mars or even more distant planets.

Laser communication units are lighter and smaller than today’s onboard radio systems, promising to cut mission costs and provide opportunities for new science payloads.

“The participation of the ESA ground terminal at Tenerife in NASA’s project is an important milestone in this new capability,” said Badri Younes, deputy associate administrator for space communications and navigation at NASA’s Headquarters in Washington DC.

“Together, we have demonstrated at the very beginning of the optical communication era the value of interoperable communication between our space agencies.”

With the first two communication passes with LADEE on 26 October and six more to 29 October, the ESA team on Tenerife are tweaking the station hardware – especially for the uplink – and improving procedures.

“Some initial difficulties with the extremely accurate pointing necessary for laser communication are being investigated, but this is quite normal at this stage,” says ESA’s Klaus-Juergen Schulz, responsible for ground station systems at the European Space Operations Centre, Darmstadt, Germany.

“We are already confident that the test campaign will confirm the practicality of high-data-rate optical links for future missions.”

During the coming weeks, ESA engineers will test uplink communications at 20 Mbit/s and obtain accurate ‘time-of-travel’ measurements to be used for calculating the spacecraft’s orbit.

Using special equipment from the DLR German Aerospace Center’s Institute for Communication and Navigation, the team will monitor atmospheric conditions during transmission and learn how to improve performance even further.

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ESA's Optical Ground Station (OGS) is 2400 m above sea level on the volcanic island of Tenerife. Aside from experiments for quantum communication and teleportation, the OGS is also used for standard laser communication with satellites, for observation of space debris or for finding new asteroids.

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Quelle: ESA

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Update: 4.12.2013 

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LADEE Instruments Healthy and Ready for Science

Now in orbit around the moon, NASA's newest lunar mission has completed the commissioning phase, and its science instruments have passed their preliminary checks.
The Lunar Atmosphere and Dust Environment Explorer (LADEE), launched Sept. 6, 2013, carries three science instruments designed to gather detailed information about the structure and composition of the thin lunar atmosphere and determine whether dust is being lofted into the lunar sky. A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.
“This is very promising for LADEE’s science phase – we are already seeing the shape of things to come,” said Rick Elphic, LADEE project scientist at NASA’s Ames Research Center in Moffett Field, Calif., the center that is managing the mission.
The mission's commissioning phase lasted roughly one month, a period in which the spacecraft remained in a high-altitude preliminary orbit and the instruments were turned on, checked and calibrated.
All three science instruments are in good health, according to the mission's payloads manager, Robert Caffrey at NASA's Goddard Space Flight Center in Greenbelt, Md. "The sensitivity of the instruments is very high, and we are looking forward to an exciting science phase!"
The Lunar Dust Experiment (LDEX), built to collect and analyze lunar dust particles in the moon's thin atmosphere, is fully operational. The instrument recorded its first dust hit within minutes after its cover was deployed on Oct. 16. In subsequent orbits, LDEX observed dozens of dust particles, indicating an impact rate on the order of one hit per minute. Preliminary analysis suggests the particle sizes are much smaller than one micrometer in radius.
The Ultraviolet and Visible Light Spectrometer (UVS), designed to probe the composition of the lunar atmosphere, made its first measurements shortly after the telescope door opened on Oct. 16. The instrument has been performing as expected and has conducted a series of pointing and instrument-performance calibrations, including looking at the limb of the moon and performing solar crossings by aiming the solar viewer at the sun and panning back and forth.
The Neutral Mass Spectrometer (NMS), which will measure variations in the lunar atmosphere over multiple lunar orbits, is operating normally. One of the first steps in getting the NMS ready for science measurements was to remove the cover of the instrument and expose the mass spectrometer to the lunar atmosphere. To do this, a pyrotechnic device was commanded to fire, breaking a ceramic to metal to ceramic seal, and the cover flew away from the spacecraft. Sensors on the spacecraft detected a small amount of motion caused by this event, and measurements made before and after the cover deployment showed that trapped calibration gases had indeed been released to space.
In addition to the three science instruments, LADEE includes a Lunar Laser Communication Demonstration (LLCD) payload. LLCD has made history using a pulsed laser beam to transmit data over the 239,000 miles between the moon and Earth at a record-breaking download rate of 622 megabits per second (Mbps). LLCD is NASA's first system for two-way communication using a laser instead of radio waves. It also has demonstrated an error-free data upload rate of 20 Mbps transmitted from the primary ground station in New Mexico to the spacecraft currently orbiting the moon.
"LLCD's goal is to validate and build confidence in the technology, so that future missions will consider using it," said Don Cornwell, LLCD manager at NASA's Goddard Space Flight Center in Greenbelt, Md. "The unique ability developed by the Massachusetts Institute of Technology's Lincoln Laboratory has incredible possibilities."
In addition to LLCD, LADEE marks several other firsts. The mission is the first flight of a spacecraft developed at Ames, the first spacecraft launched on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., and the first deep-space mission to launch from NASA's Wallops Flight Facility in Virginia.
Now that the commissioning phase has ended, LADEE has lowered its orbit to get closer to the lunar surface and begin its 100-day science mission.
NASA's Science Mission Directorate in Washington funds the LADEE mission; a cooperative effort led by Ames, which manages the mission, built the spacecraft and performs mission operations. Goddard manages the science instruments and technology demonstration payload, and the science operations center. Wallops was responsible for launch vehicle integration, launch services, and launch range operations. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages LADEE within the Lunar Quest Program Office.
Quelle: NASA   
 
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Update. 29.12.2013
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LADEE Project Scientist Update: Intial Observations of Chang’e 3 Landing
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Much of the world was watching the Chang'e 3 landing in northern Mare Imbrium at 13:10 UTC Dec. 14, 2013. NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) was watching too.

In the evening of Friday, Dec. 13, Pacific Time, LADEE controllers uploaded a command sequence that scheduled the science instruments for operations during the Chang'e 3 landing period. LADEE's science instruments gathered data on the dust and gas species before and after the landing to provide the science team with a comparison.

The Neutral Mass Spectrometer (NMS) was running in a mode that would allow it to monitor native lunar atmospheric species, as well as those resulting from Chang'e 3's propulsion system. These combustion products were known to include diatomic nitrogen, water, diatomic hydrogen and several other species. The two other LADEE science instruments, the Lunar Dust Experiment (LDEX) and the Ultraviolet-Visible Spectrometer (UVS), ran in their normal configurations. Together they are able to detect ejected dust and gas species from a propulsion system, provided these products could make the long trek to LADEE's position, which was far from the Chang’e-3 landing site.  

LADEE's retrograde, near-equatorial orbit never goes beyond approximately 22.5 degrees north and south latitude. Chang'e 3's landing site was far to the north of LADEE’s path, at 44.12 degrees north and 19.51 degrees west. At the time of landing, LADEE was orbiting over a different part of the moon east of the Chang'e 3 path, at 21.77 degrees south latitude and 82.17 degrees east longitude - more than 3,400 km (2,100 miles) away.

At 13:41 UTC, about 30 minutes after the Chang’e 3 landing, LADEE flew over 19.51 degrees west longitude. At this time, LADEE was still more than 1,300 km (800 miles) to the south of the landing site. The NMS had started exosphere observations at 13:22 UTC and would continue for 55 minutes as LADEE sped across the lunar sunrise terminator and into lunar night. The UVS had performed atmospheric scans one orbit previous (LADEE's orbit period is about 2 hours), around 12:15 UTC, and would do so again later. The LDEX was operating normally, recording dust impacts prior to, during and after the Chang'e 3 descent.

Surprisingly, the LADEE science teams' preliminary evaluation of the data has not revealed any effects that can be attributed to Chang'e 3. No increase in dust was observed by LDEX, no change was seen by UVS, no propulsion products were measured by NMS. Evidently, the normal native lunar atmospheric species seen by UVS and NMS were unaffected as well. It is actually an important and useful result for LADEE not to have detected the descent and landing. It indicates that exhaust products from a large robotic lander do not overwhelm the native lunar exosphere. As the descent video shows, the interval of time that dust was launched by the lander is very short, perhaps less than 15 seconds.  LADEE would probably have had to be in just the right place at the right time to intercept it.  Also, significant amounts exhaust products apparently cannot migrate to large distances (hundreds and thousands of miles) and linger with sufficient density to be measured. We can compare these results to theoretical predictions of gas and exhaust plume particle ejecta, and update our understanding of the interaction of lander propulsion systems with surface materials. In many ways, this has been a very useful experiment!

Quelle: NASA

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Update: 30.01.2014 
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NASA moon mission captures fleeting view of sister craft
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Coupling a fortuitous orbital alignment with meticulous planning, a camera aboard NASA's Lunar Reconnaissance Orbiter caught a smeared glimpse of another moon probe in an image released Wednesday. 
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NASA's LADEE spacecraft is seen in this geometrically corrected image from the Lunar Reconnaissance Orbiter taken on Jan. 14, U.S. time. Photo credit: NASA/GSFC/Arizona State University
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LRO and the Lunar Atmosphere and Dust Environment Explorer, or LADEE, mission are NASA's two probes currently flying around the moon. The two satellites fly in different orbits and only occasionally pass near each other.

 

But scientists in charge of the Lunar Reconnaissance Orbiter Camera calculated how to record a view of LADEE on Jan. 14 as the two probes traveled at near-perpendicular angles more than 20 miles over the moon's tortured surface.

 

"Since LROC is a pushbroom imager, it builds up an image one line at a time, thus catching a target as small and fast as LADEE is tricky! Both spacecraft are orbiting the moon with velocities near 1600 meters per second (3600 mph), so timing and pointing of LRO needs to be nearly perfect to capture LADEE in an LROC image," wrote Mark Robinson, LROC's principal investigator at Arizona State University in Tempe.

 

During the Jan. 14 encounter, controllers commanded LRO to roll 34 degrees to the west to line up the spacecraft's narrow-angle camera with LADEE's expected position on its flight path. LRO's imager was designed to snap sharp pictures of the moon, not fast-moving nearby spacecraft, so the initial result showed LADEE as a smeared streak backdropped by a clear landscape of lunar craters.
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A comparison of LADEE's image from the LRO camera with an artist's concept. The labels on the artist's concept are matched to the resolution of LRO's narrow-angle camera. Photo credit: NASA/GSFC/Ames/Arizona State University
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Scientists used a technique known as geometric correction to sharpen the view of LADEE, but the spacecraft is still blurry. The corrected image also had the result of smearing the lunar landscape in the background.
"Despite the blur it is possible to find details of the spacecraft, which is about 1 meter wide and 2 meters long. You can see the engine nozzle, bright solar panel, and perhaps a star tracker camera (especially if you have a correctly oriented schematic diagram of LADEE for comparison)," Robinson wrote.
LRO launched in June 2009 to map the lunar surface and complete a geological survey of the moon, revealing new insights into how the moon formed and evolved, creating a global lunar atlas, and helping scientists find deposits of watery compounds.
Since arriving in lunar orbit in October, LADEE achieved the first high-speed laser communications link-up between the moon and Earth and is now collecting data on the moon's tenuous atmosphere.
LRO and LADEE were joined at the moon in December by China's Chang'e 3 lander, which deployed a small mobile rover. LRO's camera has already imaged the Chinese probe on the lunar surface.
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NASA's LRO Snaps a Picture of NASA's LADEE Spacecraft
 

With precise timing, the camera aboard NASA's Lunar Reconnaissance Orbiter (LRO) was able to take a picture of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft as it orbited our nearest celestial neighbor. The Lunar Reconnaissance Orbiter Camera (LROC) operations team worked with its LADEE and LRO operations counterparts to make the imaging possible.

 

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LRO imaged LADEE, about 5.6 miles beneath it, at 8:11 p.m. EST on Jan. 14, 2014. (LROC NAC image M1144387511LR. Image width is 821 meters, or about 898 yards.)
Image Credit: NASA/Goddard/Arizona State University
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LADEE is in an equatorial orbit (east-­to-­west) while LRO is in a polar orbit (south-­to-­north). The two spacecraft are occasionally very close and on Jan. 15, 2014, the two came within 5.6 miles (9 km) of each other. As LROC is a push-broom imager, it builds up an image one line at a time, so catching a target as small and fast as LADEE is tricky. Both spacecraft are orbiting the moon with velocities near 3,600 mph (1,600 meters per second), so timing and pointing of LRO must be nearly perfect to capture LADEE in an LROC image.
LADEE passed directly beneath the LRO orbit plane a few seconds before LRO crossed the LADEE orbit plane, meaning a straight down LROC image would have just missed LADEE. The LADEE and LRO teams worked out the solution: simply have LRO roll 34 degrees to the west so the LROC detector (one line) would be in the right place as LADEE passed beneath.
As planned at 8:11 p.m. EST on Jan. 14, 2014, LADEE entered LRO’s Narrow Angle Camera (NAC) field of view for 1.35 milliseconds and a smeared image of LADEE was snapped. LADEE appears in four lines of the LROC image, and is distorted right­to­left. What can be seen in the LADEE pixels in the NAC image?
Step one is to minimize the geometric distortion in the smeared lines that show the spacecraft. However, in doing so the background lunar landscape becomes distorted and unrecognizable (see above). The scale (dimension) of the NAC pixels recording LADEE is 3.5 inches (9 cm), however, as the spacecraft were both moving about 3,600 mph (1,600 meters per second) the image is blurred in both directions by around 20 inches (50 cm). So the actual pixel scale lies somewhere between 3.5 inches and 20 inches. Despite the blur it is possible to find details of the spacecraft, which is about 4.7 feet (1.9 meters) wide and 7.7 feet (2.4 meters) long. The engine nozzle, bright solar panel and perhaps a star tracker camera can be seen (especially if you have a correctly oriented schematic diagram of LADEE for comparison).
LADEE was launched Sept. 6, 2013. LADEE is gathering detailed information about the structure and composition of the thin lunar atmosphere and determining whether dust is being lofted into the lunar sky.
LRO launched Sept. 18, 2009. LRO continues to bring the world astounding views of the lunar surface and a treasure trove of lunar data.
NASA’s Goddard Space Flight Center in Greenbelt, Md., manages the LRO mission. NASA's Ames Research Center in Moffett Field, Calif., manages the LADEE mission.
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This subsection of the LRO image, expanded four times, shows the smeared view of LADEE.
Image Credit: NASA/Goddard/Arizona State University
Quelle: NASA

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Update: 15.02.2014

 

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NASA's LADEE Moon Orbiter Snaps First Lunar Photos

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The first images from LADEE’s star tracker camera (NASA/Ames)

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Last month our attention-hounding moon photobombed SDO’s pictures of the sun, and now it’s gotten in the way of yet another robot spacecraft’s view: NASA’s Lunar Atmosphere and Dust Environment Explorer, aka LADEE, which was just trying to take some nice pictures of the stars. What gives, moon?

Actually these are images of the Moon intentionally captured by LADEE’s star tracker cameras on Feb. 8, 2014, at 23:45 UTC (6:45 p.m. ET). The star tracker instrument is a wide-angle camera that’s used by the spacecraft to determine its orientation in space based on the known positions of background stars. Star trackers aren’t specifically designed for taking pretty pictures of things like planets and moons “but they can sometimes provide exciting glimpses of the lunar terrain,” according to LADEE project manager Butler Hine.

The five images of the moon captured on Feb. 8 are the first ones to be downlinked by the LADEE team.

Taken at one-minute intervals while the spacecraft was traveling along its 156-mile-high equatorial orbit at a velocity of about 60 miles/minute (3,600 mph), the images show various craters, mountain ranges, and lava plains on the lunar surface.

Although the images look pretty well-lit, they were actually taken over the lunar night side. All illumination is coming from reflected light off the Earth — which, coincidentally, is why the stars are visible. If the spacecraft had been on the sunlit side of the moon, the glare would have been much too bright for its camera to resolve any stars. (Cue the Apollo conspiracy theories in three… two… one…)

Quelle: D-News

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Update: 6.03.2014

 

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Laserkommunikation zwischen Mond und Erde
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Im Empfangsteleskop fokussiertes Empfangssignal von der Mondsonde, links mit geringen atmosphärischen Störungen (enge Konzentration der Intensität), rechts bei starken atmosphärischen Turbulenzen (führt zu einer Aufweitung des fokalen Intensitätsmusters).
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Rund 400 000 Kilometer hatte das Laserlicht zurückgelegt und die Erdatmosphäre durchquert, bevor es von der optischen Bodenstation der ESA auf Teneriffa empfangen wurde. Gesendet wurde das Signal vom Lunar Lasercomm Space Terminal (LLST) an Bord der NASA-Sonde LADEE, die seit Oktober 2013 um den Mond kreist.

Wissenschaftler des Deutschen Zentrums für Luft- und Raumfahrt (DLR) haben nun in Kooperation mit der ESA das LLST-Signal mit der Zielkamera und einem schnellen Sekundärsensor analysiert. Damit wurde erstmals nun auch von Europäern ein optischer Link durch die Erdatmosphäre nach seinem langen Weg durch den Weltraum vermessen.

Das LLST bildet zusammen mit seiner Bodenstation in White Sands im US-Bundesstaat New Mexico das „Lunar Laser Communication Demonstration“ (LLCD)-Experiment der Lincoln Labs des Massachusetts Institute of Technology (MIT). „Das Experiment hat erstmals die Kommunikation über einen optischen Link vom entfernten Mond zur Erde erfolgreich demonstriert", betont Dr. Igor Zayer, Leiter der Bodenstation-Subsysteme bei der ESA in Darmstadt. Die ESA hat hierbei – in einer Kooperation mit der NASA und dem MIT – mit ihrer Bodenstation auf Teneriffa am Experiment teilgenommen und erfolgreich mit der Sonde kommuniziert.  

Das Ergebnis der DLR-Signalauswertung: „Der Einfluss der Atmosphäre ist weniger stark als erwartet, die Qualität des Signals ist sehr gut“, sagt Dirk Giggenbach vom DLR-Institut für Navigation und Kommunikation in Oberpfaffenhofen. Erfahrungen mit den erforderlichen Sensoren und Algorithmen für die Auswertung hatte das Team des Instituts bereits bei Testreihen mit der Übertragung eines Laserstrahls von einem Flugzeug und von verschiedenen niedrigfliegenden Satelliten gewonnen.

Jetzt aber konnte die Technologie der optischen Kommunikation mit einer Mondsonde erstmals unter realen Weltraumbedingungen erprobt werden: „Den größten Teil der Strecke legt der Laserstrahl ohne störende Atmosphäre zurück, aber die wenigen Kilometer Erdatmosphäre am Pfad-Ende verzerren und dämpfen das Signal erheblich“, betont Dirk Giggenbach. Diese Störungen untersuchen die DLR-Forscher mit Sensoren und charakterisieren den Übertragungskanal. „Nur so können wir abschätzen, wie man die Laserübertragung verbessern kann und welche Verluste man bei der Übertragung der Daten hinnehmen muss.“

Die Daten des LLCD-Experiments wurden von drei optischen Bodenstationen – den amerikanischen Stationen White Sands und Table Mountain sowie der Empfangsstation der ESA auf Teneriffa – empfangen. Das Interesse an der neuen Technologie ist groß: Die bisher erprobte und verwendete Technik, über Radio- und Mikrowellen zu kommunizieren, erreicht ihre Grenzen. Die kurzwelligeren optischen Trägerfrequenzen hingegen bieten höhere Datenraten.

Die Blu-Ray-Version des Hollywoodfilms „Apollo 13“ würde mit seinen 36 800 MB gerade einmal 7,9 Minuten vom Mond zur Erde benötigen. Würde der Film über die S-Band-Verbindung der Sonde übertragen, müsste man auf der Erde beinahe 639 Stunden – und somit fast einen Monat – auf die Daten warten. „Zukünftige Missionen können erheblich vom Einsatz der optischen Kommunikation profitieren, da mehr Daten in kürzerer Zeit zur Erde übertragen werden können.“ Für Mond- oder planetare Missionen könnte diese Art der Datenübertragung hilfreich sein und Rover könnten hochaufgelöste 3D-Aufnahmen in Echtzeit übermitteln.

Quelle: ESA

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Update: 19.03.2014 

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ScienceShot: LADEE Discovers the Moon's Dust Halo, Finally

THE WOODLANDS, TEXAS—After decades of searching, NASA scientists have detected the veil of dust kicked up by tiny meteoroid impacts on the moon. The Apollo astronauts and many spacecraft had tried to detect sunlight reflected from the dust and failed. So, instead, the scientists of the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft used an onboard instrument that detects micrometer-size dust particles when they hit the instrument at several thousand kilometers per hour and vaporize. Orbiting the moon as low as a few tens of kilometers above the surface, LADEE detected a dust impact every minute or two on average except when a meteoroid shower hitting the moon kicked up many more times the debris. Researchers should be able to use these LADEE observations to see whether the impact debris blown off the moons of Pluto will present a hazard to the New Horizons spacecraft when it flies by the ice dwarf planet in July of next year.

Quelle: AAAS

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Update: 4.04.2014 

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Take the Plunge: LADEE Impact Challenge
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NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft is gradually lowering its orbital altitude over the moon. LADEE will continue to make important science observations before its planned impact into the lunar surface later this month.
When will it impact the lunar surface? NASA wants to hear your best guess!
LADEE mission managers expect the spacecraft will impact the moon’s surface on or before April 21. On April 11, ground controllers at NASA's Ames Research Center in Moffett Field, Calif., will command LADEE to perform its final orbital maintenance maneuver prior to a total lunar eclipse on April 15, when Earth’s shadow passes over the moon. This eclipse, which will last approximately four hours, exposes the spacecraft to conditions just on the edge of what it was designed to survive.
This final maneuver will ensure that LADEE's trajectory will impact the far side of the moon, which is not in view of Earth and away from any previous lunar mission landings. There are no plans to target a particular impact location on the lunar surface, and the exact date and time depends on several factors.
"The moon's gravity field is so lumpy, and the terrain is so highly variable with crater ridges and valleys that frequent maneuvers are required or the LADEE spacecraft will impact the moon’s surface," said Butler Hine, LADEE project manager at Ames. "Even if we perform all maneuvers perfectly, there's still a chance LADEE could impact the moon sometime before April 21, which is when we expect LADEE's orbit to naturally decay after using all the fuel onboard."
Anyone is eligible to enter the "Take the Plunge: LADEE Impact Challenge." Winners will be announced after impact and will be e-mailed a commemorative, personalized certificate from the LADEE program. The submissions deadline is 3 p.m. PDT Friday, April 11.
“We want to thank all those that watched LADEE launch and have followed the mission these past months,” said Jim Green, NASA’s Director for Planetary Science at NASA Headquarters in Washington. “Our Moon holds a special place in so many cultures, and because of LADEE, we’ll know more than ever before about our nearest neighbor.”
LADEE's mission marked several firsts. It was the first demonstration of Optical Laser Communications from space (sent data six times faster than radio), and the first deep space spacecraft designed and built "in house" at NASA’s Ames Research Center.  It was also the first payload to launch on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., Va., and was the first deep space mission to launch from NASA's Goddard Space Flight Center's Wallops Flight Facility on Wallops Island, Va., when millions watched the night launch on Sept. 6, 2013. 
The vending-machine size spacecraft has been orbiting the moon since Oct. 6. On Nov. 10, LADEE began gathering science data, and on Nov. 20, the spacecraft entered its science orbit around the moon's equator. LADEE has been in extended mission operations following a highly successful 100-day prime science phase.
LADEE's three science payload instruments have been working to unravel the mysteries of the lunar atmosphere and dust environment acquiring to date more than 700,000 measurements. In its previous orbit, LADEE's closest approach to the moon’s surface was between 20 and 50 km, and its farthest point was between 75 and 150 km – a unique position that allows the spacecraft to frequently pass from lunar day to lunar night, approximately every two hours. This vantage provides data about the full scope of changes and processes occurring within the moon's tenuous atmosphere.
Scientists hope to address a long-standing question: Was lunar dust, electrically charged by sunlight, responsible for the pre-sunrise glow detected during several Apollo missions above the lunar horizon? LADEE also is gathering detailed information about the structure and composition of the thin lunar atmosphere.
A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.
Quelle: NASA
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Update: 5.04.2014
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Lunar dust mission still chasing mystery of ‘horizon glow’

NASA is preparing one last blast for its expired Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft — a controlled crash into the Moon’s surface, probably on 21 April. But before it goes, LADEE will take a final shot at unravelling one of the main mysteries it went to the Moon to uncover.

A major goal of the mission was to understand a bizarre glow on the Moon’s horizon, spotted by Apollo astronauts just before sunrise. “So far we haven’t come up with an explanation for that,” project scientist Rick Elphic, of NASA’s Ames Research Center in Moffett Field, California, said at a media briefing on 3 April. One leading idea is that the Sun’s ultraviolet rays cause lunar dust particles to become electrically charged. That dust then lofts upwards, forming a cloud that caught the light and the astronauts’ eyes.

LADEE carries an instrument that measures the impact of individual dust particles, as well as the collective signal from smaller particles. Lunar scientists had expected a certain amount of tiny dust to explain what the Apollo astronauts saw. But LADEE didn’t find it. “We did measure a signal that indicates that the amount of lofted dust has to be at least two orders of magnitude below the expectations that were based on the Apollo reports,” says Mihály Horányi, the instrument’s principal investigator, who is at the University of Colorado. Perhaps the dust lofting happens only occasionally, he suggests, and the astronauts were in just the right place at the right time to see it.

LADEE will try one more time to unravel the horizon-glow mystery. As it gets closer and closer to the lunar surface, it will point its star tracker towards the Moon’s horizon to try to replicate the angle and conditions under which the astronauts saw the glow. The star tracker is not designed for high-resolution imaging, but Elphic says that it’s worth looking.

This weekend, mission managers will guide LADEE on a trajectory just 3 kilometres above the Apennine mountains on the Moon’s near side. The goal is to see what sort of dust LADEE can spot so close to the surface. Then it will move slightly higher for its remaining few weeks before plunging to its doom. It is destined to follow the natural decay of its orbit and vaporize itself on the lunar far side.

LADEE scientists have plenty of science to distract them from mourning. The spacecraft made the best measurements ever of the Moon’s dusty envelope, generated as tiny meteorites bombard its surface. The mission also discovered exotic atoms such as neon, magnesium and aluminium in the Moon’s outer atmosphere.

Quelle: nature

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Update: 20.04.2014

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NASA Completes LADEE Mission with Planned Impact on Moon's Surface

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Ground controllers at NASA's Ames Research Center in Moffett Field, Calif., have confirmed that NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft impacted the surface of the moon, as planned, between 9:30 and 10:22 p.m. PDT Thursday, April 17.

LADEE lacked fuel to maintain a long-term lunar orbit or continue science operations and was intentionally sent into the lunar surface. The spacecraft's orbit naturally decayed following the mission's final low-altitude science phase.

During impact, engineers believe the LADEE spacecraft, the size of a vending machine, broke apart, with most of the spacecraft’s material heating up several hundred degrees – or even vaporizing – at the surface. Any material that remained is likely buried in shallow craters.

"At the time of impact, LADEE was traveling at a speed of 3,600 miles per hour – about three times the speed of a high-powered rifle bullet," said Rick Elphic, LADEE project scientist at Ames. "There’s nothing gentle about impact at these speeds – it’s just a question of whether LADEE made a localized craterlet on a hillside or scattered debris across a flat area. It will be interesting to see what kind of feature LADEE has created."

In early April, the spacecraft was commanded to carry out maneuvers that would lower its closest approach to the lunar surface. The new orbit brought LADEE to altitudes below one mile (two kilometers) above the lunar surface. This is lower than most commercial airliners fly above Earth, enabling scientists to gather unprecedented science measurements.

On April 11, LADEE performed a final maneuver to ensure a trajectory that caused the spacecraft to impact the far side of the moon, which is not in view of Earth or near any previous lunar mission landings. LADEE also survived the total lunar eclipse on April 14 to 15. This demonstrated the spacecraft's ability to endure low temperatures and a drain on batteries as it, and the moon, passed through Earth's deep shadow.

In the coming months, mission controllers will determine the exact time and location of LADEE's impact and work with the agency’s Lunar Reconnaissance Orbiter (LRO) team to possibly capture an image of the impact site. Launched in June 2009, LRO provides data and detailed images of the lunar surface.

"It's bittersweet knowing we have received the final transmission from the LADEE spacecraft after spending years building it in-house at Ames, and then being in constant contact as it circled the moon for the last several months," said Butler Hine, LADEE project manager at Ames.

Launched in September 2013 from NASA's Wallops Flight Facility in Virginia, LADEE began orbiting the moon Oct. 6 and gathering science data Nov. 10. The spacecraft entered its science orbit around the moon's equator on Nov. 20, and in March 2014, LADEE extended its mission operations following a highly successful 100-day primary science phase.

LADEE also hosted NASA’s first dedicated system for two-way communication using laser instead of radio waves. The Lunar Laser Communication Demonstration (LLCD) made history using a pulsed laser beam to transmit data over the 239,000 miles from the moon to the Earth at a record-breaking download rate of 622 megabits-per-second (Mbps). In addition, an error-free data upload rate of 20 Mbps was transmitted from the primary ground station in New Mexico to the Laser Communications Space Terminal aboard LADEE.

LADEE gathered detailed information about the structure and composition of the thin lunar atmosphere. In addition, scientists hope to use the data to address a long-standing question: Was lunar dust, electrically charged by sunlight, responsible for the pre-sunrise glow seen above the lunar horizon during several Apollo missions?

"LADEE was a mission of firsts, achieving yet another first by successfully flying more than 100 orbits at extremely low altitudes," said Joan Salute, LADEE program executive, at NASA Headquarters in Washington. "Although a risky decision, we're already seeing evidence that the risk was worth taking.”

A thorough understanding of the characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury and the moons of outer planets.

NASA also included the public in the final chapter of the LADEE story. A “Take the Plunge” contest provided an opportunity for the public to guess the date and time of the spacecraft’s impact via the internet. Thousands submitted predictions. NASA will provide winners a digital congratulatory certificate.

Quelle: NASA

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Grand finale: NASA spacecraft LADEE crashes on dark side of moon

NASA’s LADEE mission ended with a bang when the spacecraft crashed into the lunar surface Thursday. The Lunar Atmosphere and Dust Environment Explorer smashed into the dark side of the moon between 9:30 and 10:22 p.m., according to NASA officials.

The vending-machine-sized spacecraft ran out of fuel and collided with the moon at a speed of roughly 3,600 miles per hour -- or “about three times the speed of a high-powered rifle bullet,” Rick Elphic, LADEE project scientist at NASA Ames Research Center said in a statement. The doomed satellite encountered so much heat -- hundreds of degrees -- that as it broke up during impact, parts of it may have even vaporized.

The moon has an extremely lumpy gravity field, and so LADEE’s handlers have had to maneuver often to keep it from veering out of orbit and then falling to the surface. But before the spacecraft’s final dive, the team was able to bring it into a very low orbit, allowing them a rare opportunity to make measurements from less than a mile above the lunar surface.

LADEE, launched in September 2013, was sent to study the moon’s exceedingly thin lunar atmosphere. In this sparse "exosphere," the molecules are so far apart that they don't run into each other. The researchers were also looking to solve a decades-old mystery that began when Apollo astronauts saw bright streamers stretching across the lunar heavens. Scientists think this phenomenon was caused by tiny dust grains kicked many miles into the air becoming electrically charged by sunlight, but they hadn’t been able to test that theory before.

LADEE was also the first mission to use laser instead of radio waves for two-way communication, allowing it to transmit boatloads of data at a record-breaking speed of 622 megabits per second. Using laser instead of radio allowed them to transmit data six times faster, using half the weight in equipment at 25% less power,  Don Cornwell, the mission manager for the Lunar Laser Communications Demonstration, said before the launch. 

The mission’s launch also became infamous with the inadvertent launch of the "rocket frog" -- an aerial amphibian caught on camera as the rocket carrying LADEE roared to life and apparently blasted the poor animal sky-high.

In the coming months, scientists hope to pinpoint when the spacecraft actually hit the ground. They also want to use NASA’s Lunar Reconnaissance Orbiter to take photos of the crash site, to see what shape the debris left in the lunar surface.

Quelle: SN

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Update: 25.04.2014

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LADEE Project Scientist Update: The Legacy Lives On!

NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft has impacted the Moon, capping an extremely successful operational mission. Science analysis will continue for months, as the science teams churn through the data and write papers about their findings. So LADEE is gone, but its science legacy lives on!

LADEE ran its science instruments almost non-stop right up to impact the evening of April 17, 2014, in an effort to gather as much low-altitude data as possible. Further study of the returned data will reveal what the instruments saw at these amazingly low orbits, just a few kilometers above the surface. Early results suggest that LADEE was low enough to see some new things, including increased dust density and possibly new atmospheric species. In an incredible race with time, LADEE’s Real Time Operations team queued and downloaded all science files just minutes prior to LADEE's impact.

As the clock was running out on the LADEE mission, we took advantage of an opportunity to replicate observations by the Apollo astronauts more than 40 years ago. (We hinted at this in an earlier update). We used one of the star tracker cameras to gaze out over the Moon's horizon, while LADEE was in the deep darkness of the lunar night and over the far side where no Earthshine can reach.

In the minutes before orbital sunrise, when LADEE emerged from shadow into sunlight, we commanded the spacecraft to take a series of images. We wanted to see the same scene the astronauts saw, with the sun just below the horizon. In this configuration, we could view anything that might scatter sunlight. On Earth, "rosy-fingered dawn" paints the sky prior to sunrise because aerosols and dust particles suspended in the atmosphere scatter the sunlight. With the sun below the horizon, the reflected and scattered light makes the sunrise glow for an observer to see in the dark shadow beyond. However, the very low dust densities that LADEE's Lunar Dust Experiment (LDEX) measured should not produce such a sunrise glow – there were just too few particles along the line of sight to scatter measurable light. Yet some Apollo astronauts reported a pre–sunrise glow and even rays of light, as if the sun was shining through notches of the lunar mountains, and the light was scattered by…something. Could LADEE spot this? 

Shown here is a series of images taken on one such occasion, Saturday, April 12. The series begins with LADEE viewing the lunar horizon ahead, a few minutes before orbital sunrise. At this position, there is already a glow in the sky above the completely dark surface of the Moon (right), though the sun is many degrees below the horizon. LADEE’s orbital motion makes the stars appear to move to the left. The same motion brings the sun closer to the horizon ahead and the glow gets brighter. In fact, the glow becomes so bright, parts of the image are saturated. Finally, sunrise fully saturates the camera image. This sequence is the closest thing to the astronaut's orbital viewpoint that LADEE could provide!

The shape of this glow is familiar; we've seen it before. The images reveal a phenomenon that even we can see during a dark, clear night after sunset here on Earth – the zodiacal light. What is zodiacal light? It is the scattered sunlight from billions upon billions of dust grains, not at the Moon, but in the innermost reaches of the solar system. The origin of this dust appears to be comets, which shed gas and dust in their orbital progress around the sun. The lenticular shape of the zodiacal light, seen in the LADEE star tracker images, results from the tendency of the dust to be more concentrated near the orbital plane of the planets.

Unlike Eugene Cernan's sketches from his vantage point in the Apollo 17 command module, America, LADEE saw no rays or other strange features - just good old zodiacal light, plus possibly the outer fringes of the sun's corona. LADEE took several sequences of these orbital sunrise images, and for now, nothing has shown up that clearly is lunar in origin.  In the coming weeks and months, we'll carefully analyze these images, and perhaps something related to levitated lunar dust will emerge.

But it sure looks like sunrise is just as impressive from LADEE's v


Tags: LADEE Mondsonde LADEE mission LLCD-Laser 

3506 Views

Freitag, 25. April 2014 - 21:43 Uhr

Astronomie - NASA-Weitwinkel-Infrared Survey Explorer (WISE) und Spitzer Weltraumteleskop entdecken kältesten "braunen Zwerg"

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This artist's conception shows the object named WISE J085510.83-071442.5, the coldest known brown dwarf. Brown dwarfs are dim star-like bodies that lack the mass to burn nuclear fuel as stars do.

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NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope have discovered what appears to be the coldest "brown dwarf" known -- a dim, star-like body that  surprisingly is as frosty as Earth's North Pole.

Images from the space telescopes also pinpointed the object's distance to 7.2 light-years away, earning it the title for fourth closest system to our sun. The closest system, a trio of stars, is Alpha Centauri, at about 4 light-years away.

"It's very exciting to discover a new neighbor of our solar system that is so close," said Kevin Luhman, an astronomer at Pennsylvania State University's Center for Exoplanets and Habitable Worlds, University Park. "And given its extreme temperature, it should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures."

Brown dwarfs start their lives like stars, as collapsing balls of gas, but they lack the mass to burn nuclear fuel and radiate starlight. The newfound coldest brown dwarf is named WISE J085510.83-071442.5. It has a chilly temperature between minus 54 and 9 degrees Fahrenheit (minus 48 to minus 13 degrees Celsius). Previous record holders for coldest brown dwarfs, also found by WISE and Spitzer, were about room temperature.

WISE was able to spot the rare object because it surveyed the entire sky twice in infrared light, observing some areas up to three times. Cool objects like brown dwarfs can be invisible when viewed by visible-light telescopes, but their thermal glow -- even if feeble -- stands out in infrared light. In addition, the closer a body, the more it appears to move in images taken months apart. Airplanes are a good example of this effect: a closer, low-flying plane will appear to fly overhead more rapidly than a high-flying one.

"This object appeared to move really fast in the WISE data," said Luhman. "That told us it was something special."

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Cold and Quick: a Fast-Moving Brown Dwarf

This animation shows the coldest brown dwarf yet seen, and the fourth closest system to our sun. Called WISE J085510.83-071442.5, this dim object was discovered through its rapid motion across the sky. It was first seen in two infrared images taken six months apart in 2010 by NASA's Wide-field Infrared Survey Explorer, or WISE (see orange triangles). Two additional images of the object were taken with NASA's Spitzer Space Telescope in 2013 and 2014 (green triangles). All four images were used to measure the distance to the object -- 7.2 light-years -- using the parallax effect.

The Spitzer data were used to show that the body is as cold as the North Pole (or between minus 54 and 9 degrees Fahrenheit, which is minus 48 to minus 13 degrees Celsius).

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After noticing the fast motion of WISE J085510.83-071442.5 in March of 2013, Luhman spent time analyzing additional images taken with Spitzer and the Gemini South telescope on Cerro Pachon in Chile. Spitzer's infrared observations helped determine the frosty temperature of the brown dwarf. Combined detections from WISE and Spitzer, taken from different positions around the sun, enabled the measurement of its distance through the parallax effect. This is the same principle that explains why your finger, when held out right in front of you, appears to jump from side to side when you alternate left- and right-eye views.

"It is remarkable that even after many decades of studying the sky, we still do not have a complete inventory of the sun's nearest neighbors," said Michael Werner, the project scientist for Spitzer at NASA's Jet Propulsion Laboratory in Pasadena, Calif. JPL manages and operates Spitzer. "This exciting new result demonstrates the power of exploring the universe using new tools, such as the infrared eyes of WISE and Spitzer."

WISE J085510.83-071442.5 is estimated to be 3 to 10 times the mass of Jupiter. With such a low mass, it could be a gas giant similar to Jupiter that was ejected from its star system. But scientists estimate it is probably a brown dwarf rather than a planet since brown dwarfs are known to be fairly common. If so, it is one of the least massive brown dwarfs known.

In March of 2013, Luhman's analysis of the images from WISE uncovered a pair of much warmer brown dwarfs at a distance of 6.5 light years, making that system the third closest to the sun. His search for rapidly moving bodies also demonstrated that the outer solar system probably does not contain a large, undiscovered planet, which has been referred to as "Planet X" or "Nemesis."

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This diagram illustrates the locations of the star systems closest to the sun. The year when the distance to each system was determined is listed after the system's name.

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Quelle: NASA


Tags: Cold Neighbor of Sun 

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Freitag, 25. April 2014 - 19:55 Uhr

Raumfahrt - Die Landung auf einem Asteroiden kann extrem schwierig sein

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ASU researchers build their own "patch of asteroid" inside of a small spinning satellite seen here in this artist rendering.
Photo by: Sean Amidan

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A dozen astronauts have walked on the moon, and several rovers have been piloted on Mars, giving us a good understanding of these off-world environments. But when it comes to asteroids, scientists enter uncharted territory.

Landing on an asteroid is notoriously difficult.

Asteroids have very little gravity because they have very little mass. Most of them appear to be rubble piles held together loosely, with surfaces covered in boulders and gravels and fine materials, much like the moon, but with a lot more cohesion. On an asteroid, a rock the size of a bank building weighs as much as a cricket on Earth, making an astronaut like a superman. But what would you anchor to, what you would land on and how would you move around?

Because scientists and engineers don’t know the most basic mechanical properties of an asteroid, sending a billion dollar landing mission to an asteroid is risky, and even likely to fail, until some preliminary investigations are conducted, requiring years of lead time.

A team at Arizona State University is looking to mitigate that risk and improve that schedule by building its own "patch of asteroid" inside of a small, spinning satellite costing less than $100,000. The project is called the Asteroid Origins Satellite, or AOSAT I.

“Landing on asteroids is one of the biggest challenges of our time,” roboticist Jekan Thanga said.

Thanga, an assistant professor in the School of Earth and Space Exploration at ASU, is the engineering principal investigator for AOSAT I. “And space agencies worldwide, including NASA, are very focused on meeting that challenge.”

Erik Asphaug, a planetary scientist and professor at ASU, is the science principal investigator for AOSAT I. He and Thanga plan on launching a miniature satellite later this year that will serve as the world’s first CubeSat microgravity laboratory. A CubeSat is a modular small satellite with a 10-by-10 centimeter base and various unit lengths. AOSAT I will be a 3U configuration, about the size of a loaf of bread, with two spun-up laboratories in the outer units, each housing a patch of real asteroid surface material.

In the first flight, one chamber will be filled to a depth of a few centimeters with very fine material representative of interstellar dust, or the fine "ponds" seen on several asteroids. The second chamber, otherwise identical, will be filled with bits of shock-fragmented chondrite meteorite material. Once launched into space and freely orbiting, these rocks will just tumble around – itself an interesting experiment. But to build a realistic regolith surface for scientists to explore, the satellite is spun, to create microgravity-like conditions.

“We’re taking asteroid material that landed on Earth and sending it back into space,” Asphaug said. “It’s a low-cost laboratory that really physically builds a patch of asteroid. It’ll be asteroid gravity. It’ll be made of asteroid stuff. We can do all sorts of experiments.”

To simulate the gravity field of a 300-meter-diameter asteroid, AOSAT I spins once every 4.5 minutes. It can spin faster to reproduce the regolith (surface material) conditions for much larger asteroids. This spin configuration is easily attained and stabilized by off-the-shelf approaches, making it a great approach for students to learn on.

While much of the CubeSat is off-the-shelf, the approach is novel. CubeSats have typically been used to test engineering designs in space, since it is a really constrained and relatively new form factor. Great science has been performed on CubeSats, although this has only been observational so far. CubeSats have not yet been used to do “test tube and beaker-type” experiments of the sort that are planned for AOSAT I, Thanga said.

Experiments will be conducted robotically in the end chambers. When AOSAT I is not spinning, it is a zero-gravity capsule. Here, experiments will be done to understand how dust clumps together to form asteroids – a process that plays out in zero gravity over long timescales. A simple robotic plunger is being designed to interact with the patch of regolith, and can be used to accrete a globule of particles, a miniature rubble pile asteroid that can be spun and shaken, observed by stereo cameras.

When AOSAT I starts to spin, these piles of grains will get accelerated to the outer walls. Observing that process will tell us much about nebular grain behavior and microgravity particle flows on asteroids, for example, following the formation of a crater.

Once the spinning AOSAT I has stabilized (once per few minutes), experiments will be conducted to give a better understanding of what asteroid surfaces are like. “The questions are very basic, and that’s what makes this so much fun,” says Asphaug. When you push slowly on a rock, does it lock into place or does it push aside the other rocks and slide into the surface? Do patterns form when you send a vibration through the regolith? Does cohesion dominate overwhelmingly over gravity, so that rocks stick together into aggregates? What happens when you charge the particles?

Asphaug and Thanga hope to answer these questions to help determine what kinds of devices would be best for landing on real asteroids. “An asteroid could just be lots of rock, just grouped together into this larger entity, but there’s nothing holding it together,” Thanga said. “So if something is going to grapple and try to land on this, there’s nothing to grapple to.”

Despite the small scale of the experiments (the asteroid patch will be slightly smaller than a CD case), Asphaug and Thanga are confident in the real-world applications of AOSAT.

“These rocks might not be able to tell the difference, whether they are in the AOSAT centrifuge or back on their home asteroid,” says Asphaug. Once the AOSAT is spun up to mimic the gravity field of a ~300 m asteroid (gravity field 10-5 that of Earth), then it can be used to test mechanisms for asteroid landing. The first AOSAT will use a simple arm that does some basic interactions, while next generation AOSATs will be configured with more advanced robotic equipment.

Thanga uses the analogy of a wind tunnel to describe the scientific approach to their experiments. In a wind tunnel, researchers subject small-scale models of aircraft to conditions they expect in flight. The calculations and designs are then scaled up and applied to the real thing. “We can test asteroids in this wind tunnel-like analogous system, prove and disprove theories, and get a better understanding of our models,” says Thanga.

Landing on an asteroid may be extremely difficult, but it’s also an extremely desirable goal, from many points of view. Mining asteroids, colonizing asteroids or using asteroids as stepping stones to Mars and the other planets used to be the stuff of science fiction. Now it is on the desk of NASA administrators, who are being asked to find ways to divert hazardous asteroids, and to discover new ways to utilize asteroids, and to involve asteroids as part of the astronaut pathway to Mars.

Viranga Perera, a graduate student at ASU who is managing the project systems engineering, thinks it is “fascinating that this very low-cost AOSAT platform can be used to study such a fundamental concept as planetary accretion, and that it can serve as a test bed for future asteroid sample return missions.”

The School of Earth and Space Exploration is an academic unit in ASU's College of Liberal Arts and Sciences.

Quelle:  ASU News


2633 Views

Freitag, 25. April 2014 - 11:50 Uhr

Raumfahrt - Keime im Raum! NASA brachte WHYY Mikroben zur ISS um sie bei Schwerelosigkeit zu beobachten .

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A microbe collected at WHYY was one of 48 samples recently sent to the International Space Station to test how microbes grow in microgravity. 
Recently, we reported on the Earth Microbe Biome Map. It's a huge project, where microbiologists are logging samples of microbes — like bacteria, amoebas and fungi — into a database that will create a map of the entire world, at a microscopic level. There's a second part to the project, involving the International Space Station (ISS), and a bacterium collected right here at WHYY.
On April 18, NASA launched a cargo spaceship to bring supplies and scientific experiments to the International Space Station. Along for the voyage were 48 samples of specially selected microbes.
Scientists know that we each carry a massive number of microscopic lifeforms on and in our bodies. So as humans gear up for commercial space travel and spending extended periods of time in space, microbiologists are wondering, how the microbes that are coming along with us will behave in that environment. 
"The scientific reason is to see how well various microbes grow in microgravity compared to on Earth," explains microbiologist David Coil, one of the project's researchers.
The official name is Project MERCCURI, for Microbial Ecology Researchers Combining Citizen Science and University Researchers on the ISS.
"It's sort of a tortured acronym," Coil admits.
Samples here and samples there
An identical set of the 48 samples was kept at the University of California at Davis, to serve as a baseline for comparison. 
"The astronauts will take out a sample, thaw it out, and grow it up for 96 hours. And we'll be doing the same thing here on earth at the same time, and that's what we'll use to compare the results," explains Coil.
The samples came from many sources, like sporting events, and famous icons such as the Liberty Bell. So it got us wondering, what sort of microscopic life might be lurking around WHYY? We took some samples, and a microbe found in one of them was chosen for the space flight. It's a bacterium called Macrococcus brunensis.
Microbiologist David Coil thinks it's a good pick because of its anonymity.
"Almost nothing is known about it," he says. "The best I could say about it was that it's awesome because it was isolated from llamas in the Czech Republic."
That doesn't necessarily mean a WHYY reporter has been petting Czech llamas. Coil says it shows how widely traveled microscopic species can be.
"It turns out that a lot of microbes are found everywhere. I'm sure if you looked at your computer, you could find a hundred species of microbes, some of which were originally isolated from all sorts of strange places, and if you looked hard enough you'd probably find species that weren't even known to science," Coil says. 
Go, microbes, go!
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Aside from investigating the microbes' behavior in space, the researchers have set up a competition among the chosen samples.
"Which microbe is the fastest sprinter, which grows the fastest?" says Darlene Cavalier, founder of the citizen science website SciStarter and Project Director for Project MERCCURI.
"We're doing that to play off of the fact that many of the samples came from NFL and NBA stadiums," she says.  
Quelle: newsworks
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2588 Views

Freitag, 25. April 2014 - 11:10 Uhr

Astronomie - Geheimnis der schillernde Supernova gelöst

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Supernovae are exploding stars which briefly illuminate the night sky
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An exceptionally bright supernova that baffled scientists has been explained.
It is so luminous because a galaxy sitting in front amplifies its light - making it appear 100 billion times more dazzling than our Sun.
This cosmic magnifying glass lay hidden between Earth and the supernova - and has now been detected with a telescope in Hawaii.
Continue reading the main story
Start Quote
Our explanation required a bit of magic... and scientists don't generally buy into magic”
Dr Robert Quimby
University of Tokyo
The discovery, reported in the journal Science, settles an important controversy in the field of astronomy.
In 2010, a team of scientists observed the supernova, PS1-10afx, shining 30 times brighter than any other in its class.
They concluded it was a completely new type of stellar explosion.
But while there are a few, rare supernovas that have been found with comparable luminosities, there was something odd about this one, according to Dr Robert Quimby of the University of Tokyo's Kavli Institute.
"PS1-10afx was different in just about every way. It evolved too fast, its host galaxy is too big, and it was way, way too red," he explained.
His team had another idea. They ventured that PS1-10afx was a normal Type Ia supernova magnified by a lens in the form of a massive object, such as supermassive black hole, nearby.
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The only problem: "We had no direct evidence for the lens," said Dr Quimby.
"Thus [our] explanation required a bit of magic... and scientists don't generally buy into magic."
However, he reasoned that if there was a gravitational lens magnifying the supernova, this lens would still be there today - even though the supernova has faded away.
To find it, his team used the Keck telescope in Hawaii to observe PS1-10afx's host galaxy.
"Looking at the spectra we could check to see if there was light coming from two sources at two separate distances, which is what we found," said Dr Quimby.
"There is a second, previously unidentified galaxy, hiding in plain sight in front of the supernova."
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The galaxy makes the supernova appear as four separate images

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The lens galaxy was missed previously because its light was lost in the bright glare of the supernova, the authors say.
"Although the lens galaxy is closer to us, it appears fainter because it has older stars that, like flashlights with old batteries, don't shine as bright," said Dr Quimby.
The Universe was almost a billion years younger when the supernova exploded than when its light rays were bent by the foreground lens.
"Although this warping of space time probably created four separate images of the supernova when viewed from Earth, we find that these likely appeared as a single source after atmospheric blurring," said Dr Quimby.
The discovery could provide astronomers with a new tool to measure the expansion of the Universe.
That's because PS1-10afx is the first supernova of its kind to be magnified by "strong gravitational lensing" - where multiple images of the supernova are formed - creating the extra-bright appearance.
"Each image will arrive at a different time with the exact delay dependent on how fast the Universe is expanding. In principle, measuring this delay provides a direct way to measure cosmic expansion," Dr Quimby explained.
Unfortunately, the scientists could not do this with PS1-10afx because it faded away before its importance was recognised. But now they know what to look for.
"Our discovery implies there are many more gravitationally lensed supernovae that are barely resolved, like PS1­10afx," said Prof Masamune Oguri, of the University of Tokyo.
"Our selection method can soon be applied to future surveys to improve our understanding of the expanding Universe."
Quelle: BBC

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