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Sonntag, 5. Oktober 2014 - 19:00 Uhr

Raumfahrt - Spekulation um Re-Entry von Kobalt-M Spionagesatelliten über USA

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10.09.2014

Russia Denies Burn-Up of Military Spy Satellite Over U.S.

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The Defense Ministry has challenged reports that a Kobalt-M spy satellite reentered the Earth's atmosphere and burnt up over the U.S., potentially leaving Russian military intelligence photos lying in Colorado or Wyoming.
On Sept. 3, the American Meteor Society recorded more than 30 eyewitness reports of a slow-moving fireball crossing Colorado and into southern Wyoming. Local media reported the event as a meteor entering the atmosphere, but amateur space flight observers on the spaceflight101 blog said on Tuesday it must have been a Russian Kobalt-M spy satellite, after comparing the path of the fireball to the orbits of known satellites.
Defense Ministry spokesperson Major-General Igor Konashenkov denied this on Tuesday, however, claiming that Russia keeps close tabs on its satellite fleet and that nothing out of the ordinary has happened.
"We can only guess what condition the representatives of the so-called American Meteor Society must be in to have identified a [fireball] at that altitude as a Russian military satellite," Konashenkov quipped in a comment carried by RIA Novosti.
However, the amateur claims are backed up by the U.S. Space Tracking Network, which publicly tracks the orbits of spacecraft and issues warnings when it detects a satellite that is in danger of falling from space.
On Sept. 2 it issued such a warning for Kosmos-2495 — the international catalogue designation for the Kobalt-M satellite.
The satellite, launched from the Plesetsk Cosmodrome near Arkhangelsk on May 6, was not equipped to digitally transmit its photographs back to its handlers at Russia's military intelligence unit, the GRU. Instead, it was designed to drop its film in special canisters from space onto Russian territory.
Interfax reported Tuesday that the satellite may have been attempting to position itself to drop a canister back to Earth, when it moved into too low of an orbit — thereby falling back to earth over the U.S.
It is possible that much of the satellite and its photos survived, and are now sitting somewhere in the U.S. midwest.
Quelle: The Moscow Times
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Update: 12.09.2014
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Air and Space Defense troops deny spacecraft Cosmos-2495 exploded over US territory
MOSCOW, Russia's Air and Space Defense (ASD) troops have dismissed reports of an explosion of the spacecraft Cosmos-2495 over the US territory.
"All spacecraft of Russia's orbital group are functioning in designated orbits in established modes and are steadily monitored by ground means of the space monitoring system of the Main Space Situation Exploration Center of the ASD Space Command. There are no malfunctions or deviations in the standard operation of Russian spacecraft," Colonel Alexey Zolotukhin, ASD spokesman, told ITAR-TASS.
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Update: 5.10.2014
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Space Sleuths Piece Together Fiery Fall of Russian Spy Satellite Debris

GOLDEN, Colorado - A global network of skywatching detectives has pieced together the strange story of a Russian military spy SATELLITEthat re-entered Earth's atmosphere earlier this month, the leftovers of which sparked a spectacular sky show over five U.S. states.
OBSERVERS across parts of Montana, South Dakota, Wyoming, Colorado and New Mexico caught sight of debris from the military satellite via a fireball on Sept. 2 around 10:30 p.m. Mountain Daylight Time, reporting their OBSERVATIONS to the American Meteor Society.
The focus of attention is Russia's Cosmos 2495, an Earth-imaging reconnaissance SATELLITE. It was a hefty spacecraft, in the Kobalt-M series, a family member of the Yantar chain of Russian satellites. Russia launched the SATELLITE on its intelligence-gathering mission on May 6 of this year. [Photos: Declassified U.S. Spy Satellites]
The resulting fireball from parts of the Cosmos 2495 spysat's re-entry was not only spotted by skywatchers. It was also caught that night by a number of all-sky cameras, including the Cloudbait Observatory  here in the central Colorado Rocky Mountains.
An on-line buzz about the occurrence found a home at SeeSat-L, the mailing list for visual satellite observers, which has become an invaluable tool to study all manner of spacecraft events. So here's what happened with Cosmos 2495.
SATELLITE tracker Thomas Ashcraft, of Heliotown in Santa Fe, New Mexico, captured this long-exposure view of the brilliant fireball created by debris from a suspected Russian spy satellite on Sept. 2, 2014.
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Russian spysat falls from space
This multipart Cosmos 2495 consists of an equipment module, an instrument module, a camera re-entry vehicle and a large sun SHADEwith additional antennae and sensors. It is designed to re-enter Earth's atmosphere so that its camera canister can be retrieved by a recovery crew.
At the end of its mission on Sept. 2, the Russian spysat fired its engine to begin its return to Earth. Its fiery re-entry was witnessed and videoed from a large part of western Kazakhstan. The module carrying the cargo of exposed film and a reusable camera separated, and is believed to have landed near the city of Orenburg in Russia. The remainder of the spacecraft, meanwhile, burned up as planned.
Now, it appears that the slow-moving fireball spotted over the U.S. on Sept. 2 — some 10 hours after Cosmos 2495's intelligence camera module had safely touched down — was due to a lingering leftover from the Soviet military spacecraft. [6 Biggest Spacecraft to Fall from Space]
"I believe that is the consensus now," said veteran spacecraft tracker Ted Molczan of Toronto, Canada, who maintains the SeeSat-L MAILING LIST.
After reviewing the Russian SATELLITE mission, Molczan said his analysis "strongly supported the Cosmos 2495 debris hypothesis," he told Space.com.
"Having spent much of the past two years cataloguing historical re-entry sightings, I was not surprised by these EVENTS," he added. "Of the 239 re-entries I have catalogued to date, this is the fifth case attributable to lost or un-catalogued objects that could be shown to correlate with a known parent or launch."
Like Molczan, other spacecraft trackers chimed in on the case of Cosmos 2495.
For example, astronomer Sergey Yefimov contributed very significantly to solving the mystery, Molczan recalls. On Sept. 3, Yefimov alerted Molczan to fireball sightings from western Kazakhstan and the Orenburg region of Russia, including videos that Yefimov suspected were of a SATELLITE re-entry.
Quelle: SC

 

Tags: Raumfahrt 

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Sonntag, 5. Oktober 2014 - 18:25 Uhr

Raumfahrt - Dream Chaser Space Plane startet in Stratosphäre

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Stratolaunch Systems is considering buying a smaller three-person version of Sierra Nevada’s Dream Chaser space plane to fly paying passengers into orbit.
The company, backed by MICROSOFT co-founder Paul Allen, is halfway through construction of the world’s biggest airplane.
“It’s a monster,” Stratolaunch executive director Chuck Beames said at the International Astronomical Congress in Toronto.
With a wingspan of 385 feet and six 747-class engines, the airplane is designed to serve as an airborne launch pad for sending satellites — and eventually people — into orbit.  A debut test flight is expected in 2018.
Both satellites and passenger spaceships would be released from the plane at an altitude of about 30,000 feet, then ignite their own rocket motors to reach orbit.
The Dream Chaser, which Sierra Nevada has been developing in partnership with NASA, is a winged vehicle that resembles a space shuttle orbiter. NASA bypassed Sierra Nevada for its fourth and final round of development funds and flight contracts, though the company is challenging the decision. The Government Accountability Office is expected to rule by Jan. 5.
Meanwhile, Sierra Nevada has not been idle. In addition to a year-long study contract for Stratolaunch, the company this week unveiled a new global marketing campaign to flag Dream Chaser vehicles and/or missions for aspiring space nations.
To fly on Stratolaunch, Dream Chaser likely would be scaled down 25 percent, reducing crew size from seven to three (a pilot and two passengers).
“We looked at it and showed that it was completely feasible to do this,” said Sierra Nevada senior director Craig Gravelle.
The company declined to specify what upper-stage rocket motor the spaceplane would be paired with to reach orbit. Beames said studies are still underway, including using a more robust engine that could expand crew size to four.
“Dream Chaser seemed to be the logical way to go,” Beames later told reporters in Toronto. “We feel pretty good that we have enough analysis there. Paul just hasn’t made a decision yet.”
Allen is expected to decide on the project in November or December, Beames added.
Quelle: D-News

Tags: Raumfahrt 

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Donnerstag, 2. Oktober 2014 - 21:36 Uhr

Astronomie - Sind die Religionen der Welt bereit für E.T.?

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In 1930, Albert Einstein was asked for his opinion about the possibility of life elsewhere in the universe. “Other beings, perhaps, but not men,” he answered. Then he was asked whether science and religion conflict. “Not really, though it depends, of course, on your religious views.”
Over the past 10 years, astronomers’ new ability to detect planets orbiting other stars has taken this question out of the realm of PHILOSOPHY, as it was for Einstein, and transformed it into something that scientists might soon be able to answer.
Religions and Extraterrestrial Life book coverRealization that the nature of the debate about life on other worlds is about to fundamentally change led Vanderbilt Professor of Astronomy David Weintraub to begin thinking seriously about the question of how people will react to the discovery of life on other planets. He realized, as Einstein had OBSERVED, that people’s reactions will be heavily influenced by their religious beliefs. So he decided to find out what the world’s major religions have to say about the matter. The result is a BOOK titled “Religions and Extraterrestrial Life” (Springer International Publishing) published this month.
“When I did a library search, I found only half a dozen books and they were all written about the question of extraterrestrial life and Christianity, and mostly about Roman Catholicism, so I decided to take a broader look,” the astronomer said. As a result, his book describes what religious leaders and theologians have to say about extraterrestrial life in more than two dozen major religions, including Judaism, Roman Catholicism, the Eastern Orthodox churches, the Church of England and the Anglican Communion, several mainline Protestant sects, the Southern Baptist Convention and other evangelical and fundamentalist Christian denominations, the Religious Society of Friends (Quakers), Seventh Day Adventism and Jehovah’s Witnesses, the Church of Jesus Christ of Latter-Day Saints (Mormons), Islam and several major Asian religions including Hinduism, Buddhism and the Bahá’í Faith.
Discovery of planets
The remarkable progress that astronomers have made at detecting exoplanets gives the issue of extraterrestrial life a new sense of immediacy. In 2000, astronomers had detected 50 planets orbiting other stars. Today, the number has grown to more than 1,000. If the RATE of discovery keeps up its current pace, astronomers will have identified more than a million exoplanets by the year 2045.
“If even one exoplanet shows signs of biological activity – and those signs should not be hard to detect, if living things are present – then we will know Earth is not the only place in the universe where life exists,” Weintraub points out. “Although it is impossible to prove a negative, if we have not found any signs of life after a million exoplanets have been studied, then we will know that life in the universe is, at best, exceedingly rare.”
Public OPINION POLLING indicates that about one fifth to one third of the American public believes that extraterrestrials exist, Weintraub reports. However, this varies considerably with religious affiliation.
Belief in extraterrestrials varies by religion
55 percent of Atheists
44 percent of Muslims
37 percent of Jews
36 percent of Hindus
32 percent of Christians
Of the Christians, more than one third of the Eastern Orthodox faithful (41 percent), Roman Catholics (37 percent), Methodists (37 percent), and Lutherans (35 percent) professed belief in extraterrestrial life. Only the Baptists (29 percent) fell below the one-third threshold.
Asian religions would have the least difficulty in accepting the discovery of extraterrestrial life, Weintraub concluded. Some Hindu thinkers have speculated that humans may be reincarnated as aliens, and vice versa, while Buddhist cosmology includes thousands of inhabited worlds.
Weintraub quotes passages in the Qur’an that appear to SUPPORT the idea that spiritual beings exist on other planets, but notes that these beings may not practice Islam as it is practiced on Earth. “Islam, like other faiths, has fundamentalist and conservative traditions. All Muslims, however, likely would agree that the prophetically revealed religion of Islam is a set of practices designed only for humans on earth,” Weintraub wrote.
Weintraub found very little in Judaic scriptures or rabbinical writings that BEAR on the question. The few Talmudic and Kabbalistic commentaries on the subject do assert that space is infinite and contains a potentially infinite number of worlds and that nothing can deny the existence of extraterrestrial life. At the same time, Jews don’t believe the discovery of extraterrestrial intelligence would have much effect on them. He quotes a Jewish anthropologist and scholar who has addressed this issue and concluded that the relationship beween Jews and God would not be affected in the slightest by “the existence of other life forms, newly discovered scientific realities or pan-human behavioral changes.”
Christian debate
Among Christian religions, the Roman Catholics have done the most thinking about the possibility of life on other worlds, the astronomer discovered. In fact, they have had an on-again, off-again theological debate that has gone on for a thousand years. The crux of the matter is original sin. If intelligent aliens are not descended from Adam and Eve, do they suffer from original sin? Do they need to be saved? If they do, then did Christ visit them and was he crucified and resurrected on other planets? “From a Roman Catholic perspective, if sentient extraterrestrials exist some but perhaps not all such species may suffer original sin and will require redemption,” Weintraub summarizes.
The inherent diversity of Protestant denominations, where individuals are encouraged to interpret scripture independently, has led to many conflicting approaches to the question of extraterrestrial intelligence. Weintraub determined that the views of Lutheran theologian Paul Tillich appear to represent a viable consensus. Tillich argued that the need for salvation is universal and the “saving power” of God must be everywhere. At the same time, he maintained that God’s plan for human life need not be the same as his plan for aliens.
Evangelical and fundamental Christians are most likely to have difficulty accepting the discovery of extraterrestrial life, the astronomer’s RESEARCH indicates. “…most evangelical and fundamentalist Christian leaders argue quite forcefully that the Bible makes clear that extraterrestrial life does not exist. From this perspective, the only living, God-worshipping beings in the entire universe are humans, created by God, who live on Earth.” Southern Baptist evangelist Billy Graham was a prominent exception who stated that he firmly believes “there are intelligent beings like us far away in space who worship God.”
Weintraub also identified two religions – Mormonism and Seventh-day Adventism – whose theology embraces extraterrestrials. In Mormonism, God helps exalt lesser souls so they can achieve immortality and live as gods on other worlds. And, Ellen White, who co-founded Seventh-Day Adventism, wrote that Got had given her a view of other worlds where the people are “noble, majestic and lovely” because they live in strict obedience to God’s commandments.
Are we ready?
In answer to the question “Are we ready?” Weintraub concludes, “While some of us claim to be ready, a great many of us probably are not… very few among us have spent much time thinking hard about what actual knowledge about extraterrestrial life, whether viruses or single-celled creatures or bipeds PILOTING intergalactic spaceships, might mean for our personal beliefs [and] our relationships with the divine.”
Quelle: Vanderbilt University · NASHVILLE, Tennessee

Tags: Astronomie 

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Donnerstag, 2. Oktober 2014 - 12:40 Uhr

Astronomie - Der Winter kommt ... am Südpol von Saturn-Mond Titan

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Titan has seasons just like Earth, only each season lasts over seven years instead of three months courtesy of NASA
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Gigantic polar clouds of hydrogen cyanide roughly four times the area of the UK are part of the impressive atmospheric diversity of Titan, the largest moon of Saturn, a new study led by Leiden Observatory, the Netherlands Institute for Space Research and the University of Bristol has found. The research is published today in Nature.
Titan is unique in our solar system because of its dense nitrogen-methane atmosphere, which is very similar to Earth's in some ways, but very different in others.  For example, air temperatures are around 200 degrees colder and, in contrast to the warm salt water seas of Earth, frigid hydrocarbon lakes populate Titan's surface.
Titan has seasons just like Earth, only each season lasts over seven years instead of three months due to its ponderous orbit around the Sun. After equinox in 2009, Titan's south pole entered the perpetual darkness of polar winter.  Soon after, instruments on NASA's Cassini spacecraft observed the development of a gigantic polar cloud covering over one million square kilometres – roughly four times the area of the UK.
Bristol researcher and co-author Dr Nick Teanby said: "The cloud was first seen in images from Cassini's cameras taken in 2012.  It started off quite small but soon grew to cover the entire south polar region.  This was totally unexpected and set us puzzling over what the cloud could be made of. Unfortunately, while the images showed that the cloud was very high up, at over 250km above the surface, they did not allow us to figure out what the cloud was actually made of or why it was there."
For the next two years Cassini gathered more data including infrared spectra of the cloudy region.  
Lead author Remco de Kok said: "When we looked at the spectra, we saw two large peaks that weren't present in spectra of other places on Titan.  These peaks coincided exactly with the peaks you'd expect from ice particles of hydrogen cyanide, or 'blauwzuur' (blue acid) as it's known in the Netherlands, which is highly toxic.  This was very surprising to us, since we did not expect HCN ice to be able to form so high in Titan's atmosphere."
This new research suggests that Titan's south pole must be extremely cold to allow hydrogen cyanide to condense.  In fact, the upper atmosphere must have cooled by over 50 degrees in less than a year to reach a blisteringly cold -150C.  
Remco de Kok concluded: "This is a very rapid change given Titan's long annual cycle and is much colder than previously thought possible.  It suggests that once the pole is in shadow the upper atmosphere acts as a very efficient radiator of heat, perhaps due to the high abundance of exotic hydrocarbon and nitrogen based compounds, which emit strongly in the infrared.  
"Cassini is set to continue observing Titan until it takes a dive into Saturn at the end of its mission in 2017.  It will be fascinating to see how the cloud will develop."
Quelle: University of Bristol
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TITAN’S SWIRLING POLAR CLOUD IS COLD AND TOXIC
Spectral map of Titan
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The international Cassini mission has revealed that a giant, toxic cloud is hovering over the south pole of Saturn’s largest moon, Titan, after the atmosphere has cooled in a dramatic fashion.
Scientists analysing data from the mission found that this giant polar vortex contains frozen particles of the toxic compound hydrogen cyanide.
“The discovery suggests that the atmosphere of Titan’s southern hemisphere is cooling much faster than we expected,” says Remco de Kok of Leiden Observatory and SRON Netherlands Institute for Space Research, lead author of the study published in the journal Nature.
Unlike any other moon in the Solar System, Titan is shrouded by a dense atmosphere dominated by nitrogen, with small amounts of methane and other trace gases. Almost 10 times further from the Sun than Earth, Titan is very cold, allowing methane and other hydrocarbons to rain onto its surface to form rivers and lakes.
Like Earth, Titan experiences seasons as it makes its 29-year orbit around the Sun along with Saturn. Each of the four seasons lasts about seven Earth years and the most recent seasonal switch occurred in 2009, when summer transitioned to autumn in the southern hemisphere.
In May 2012, images from Cassini revealed a huge swirling cloud, several hundred kilometres across, taking shape at the south pole.
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Artist’s impression of the change in observed atmospheric effects before, during and after equinox in 2009. The Titan globes also provide an impression of the detached haze layer that extends all around the moon (blue). 
During the first years of Cassini’s exploration of the Saturnian system, Titan sported a ‘hood’ of dense gaseous haze (white) in a vortex above its north pole, along with a high-altitude ‘hot spot’ (red). During this time the north pole was pointed away from the Sun. 
At equinox both hemispheres received equal heating from the Sun. Afterwards, the north pole tilted towards the Sun, signalling the arrival of spring, while the southern hemisphere tilted away from the Sun and moved into autumn. 
After equinox and until 2011 there was still a significant build up of trace gases over the north pole, but the vortex and hot spot had almost disappeared. Instead, similar features began developing at the south pole, which are still present today. 
These observations are interpreted as a large-scale reversal in the single pole-to-pole atmospheric circulation cell of Titan immediately after equinox, with an upwelling of gases in the summer hemisphere and a corresponding downwelling in the winter hemisphere.
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This polar vortex appears to be an effect of the change of season, with large amounts of air being heated by sunlight during the northern spring and flowing towards the southern hemisphere.
A puzzling detail about this swirling cloud is its altitude, some 300 km above Titan's surface, where scientists thought it was too warm for clouds to form.
“We really didn’t expect to see such a massive cloud so high in the atmosphere,” says Dr de Kok.
Keen to understand what could give rise to this mysterious cloud, the scientists turned to the rich data from Cassini. After careful scrutiny, they found an important clue in the spectrum of sunlight reflected by Titan’s atmosphere.
A spectrum splits the light from a celestial body into its constituent colours, revealing signatures of the elements and molecules that are present. The Visual and Infrared Mapping Spectrometer on Cassini takes spectra at many different points on Titan, mapping the distribution of the chemical compounds in its atmosphere and on its surface.
“The light coming from the polar vortex showed a remarkable difference with respect to other portions of Titan’s atmosphere,” says Dr de Kok. “We could clearly see a signature of frozen hydrogen cyanide molecules – HCN.”
Quelle: ESA
 

Tags: Astronomie 

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Donnerstag, 2. Oktober 2014 - 12:25 Uhr

Astronomie - NASA Mission zur Erforschung von Ursprung des Ozean der Stürme auf dem Mond der Erde

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Earth's moon as observed in visible light (left), topography (center, where red is high and blue is low), and the GRAIL gravity gradients (right). The Procellarum region is a broad region of low topography covered in dark mare basalt. The gravity gradients reveal a giant rectangular pattern of structures surrounding the region.
Image Credit: NASA/GSFC/JPL/Colorado School of Mines/MIT
Using data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL), mission scientists have solved a lunar mystery almost as old as the moon itself.
Early theories suggested the craggy outline of a region of the moon’s surface known as Oceanus Procellarum, or the Ocean of Storms, was caused by an asteroid impact. If this theory had been correct, the basin it formed would be the largest asteroid impact basin on the moon. However, mission scientists studying GRAIL data believe they have found evidence the craggy outline of this rectangular region -- roughly 1,600 miles (2,600 kilometers) across -- is actually the result of the formation of ancient rift valleys.
"The nearside of the moon has been studied for centuries, and yet continues to offer up surprises for scientists with the right tools," said Maria Zuber, principal investigator of NASA's GRAIL mission, from the Massachusetts Institute of Technology, Cambridge. "We interpret the gravity anomalies discovered by GRAIL as part of the lunar magma plumbing system -- the conduits that fed lava to the surface during ancient volcanic eruptions."
The surface of the moon’s nearside is dominated by a unique area called the Procellarum region, characterized by low elevations, unique composition, and numerous ancient volcanic plains.
The rifts are buried beneath dark volcanic plains on the nearside of the moon and have been detected only in the gravity data provided by GRAIL. The lava-flooded rift valleys are unlike anything found anywhere else on the moon and may at one time have resembled rift zones on Earth, Mars and Venus.  The findings are published online in the journal Nature.
Another theory arising from recent data analysis suggests this region formed as a result of churning deep in the interior of the moon that led to a high concentration of heat-producing radioactive elements in the crust and mantle of this region. Scientists studied the gradients in gravity data from GRAIL, which revealed a rectangular shape in resulting gravitational anomalies.
"The rectangular pattern of gravity anomalies was completely unexpected," said Jeff Andrews-Hanna, a GRAIL co-investigator at the Colorado School of Mines in Golden, Colorado, and lead author of the paper. "Using the gradients in the gravity data to reveal the rectangular pattern of anomalies, we can now clearly and completely see structures that were only hinted at by surface observations."
The rectangular pattern, with its angular corners and straight sides, contradicts the theory that Procellarum is an ancient impact basin, since such an impact would create a circular basin. Instead, the new research suggests processes beneath the moon’s surface dominated the evolution of this region.
Over time, the region would cool and contract, pulling away from its surroundings and creating fractures similar to the cracks that form in mud as it dries out, but on a much larger scale.
The study also noted a surprising similarity between the rectangular pattern of structures on the moon, and those surrounding the south polar region of Saturn’s icy moon Enceladus. Both patterns appear to be related to volcanic and tectonic processes operating on their respective worlds.
"Our gravity data are opening up a new chapter of lunar history, during which the moon was a more dynamic place than suggested by the cratered landscape that is visible to the naked eye," said Andrews-Hanna. "More work is needed to understand the cause of this newfound pattern of gravity anomalies, and the implications for the history of the moon."
Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface.
The twin spacecraft flew in a nearly circular orbit until the end of the mission on Dec. 17, 2012, when the probes intentionally were sent into the moon’s surface. NASA later named the impact site in honor of late astronaut Sally K. Ride, who was America's first woman in space and a member of the GRAIL mission team.
GRAIL’s prime and extended science missions generated the highest resolution gravity field map of any celestial body. The map will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.
The GRAIL mission was managed by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alabama. GRAIL was built by Lockheed Martin Space Systems in Denver.
Quelle: NASA
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Moon's hidden valley system revealed

Scientists have identified a huge rectangular feature on the Moon that is buried just below the surface.
The 2,500km-wide structure is believed to be the remains of old rift valleys that later became filled with lava.
Centred on the Moon's Procellarum region, the feature is really only evident in gravity maps acquired by Nasa's Grail mission in 2012.
But knowing now of its existence, it is possible to trace the giant rectangle's subtle outline even in ordinary photos.
Mare Frigoris, for example, a long-recognised dark stripe on the lunar surface, is evidently an edge to the ancient rift system.
"It's really amazing how big this feature is," says Prof Jeffery Andrews-Hanna.
"It covers about 17% of the surface of the Moon. And if you think about that in terms relative to the size of the Earth, it covers an area equivalent to North America, Europe and Asia combined," the Colorado School of Mines scientist told BBC News.
"When we first saw it in the Grail data, we were struck by how big it was, how clear it was, but also by how unexpected it was.
"No-one ever thought you'd see a square or a rectangle on this scale on any planet."
The study is reported in Nature magazine.
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The full Moon as seen from the Earth, with the Procellarum border structure superimposed in red
So how was this extraordinary feature produced?
Andrews-Hanna and colleagues note that the Procellarum region contains a lot of naturally occurring radioactive elements, such as uranium, thorium and potassium.
On the early Moon, these would have heated the crust, which, when it cooled would have contracted.
Mare Frigoris is evidently an edge to the ancient rift valley system
This shrinking, they propose, would have ripped the surface, opening deep valleys. The geometry is the giveaway.
On Earth, cooling and contraction will preferentially produce hexagons containing 120-degree angles.
The famous Giant's Causeway in Northern Ireland is a classic example on the small scale, but even in bigger settings, such as in East Africa's rift valleys, geological lines tend to intersect in this way.
Procellarum's giant rectangle does the same, too - because the entire feature is draped over a sphere. This means the angles at the corners are wider than 90 degrees.
"What we're seeing is a clever trick of spherical geometry. For structures on this scale, a polygon with 120-degree angles at the corners actually has four sides instead of six," explained Prof Andrews-Hanna.
The team cannot tell when the rifting occurred, but the dating of Moon rocks brought back by Apollo would suggest the valleys were filled by volcanic lavas about 3.5 billion years ago.
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Mare Frigoris is evidently an edge to the ancient rift valley system
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Giant's Causeway: Cooling basaltic rock naturally fractures into hexagons
The Grail satellites sensed very subtle variations in the pull of gravity across the Moon's surface
The new study goes some way to resolving arguments over the origins of Procellarum, which looks different to other, more circular mare (dark regions) on the Moon's surface.
For these regions, big asteroid impacts were more important in sculpting their forms.
The study is also further proof of the value of the Grail mission, led from the Massachusetts Institute of Technology.
This comprised two, near-identical satellites that chased each other around the Moon over the course of a year.
They mapped changes in the pull of gravity as they flew over areas of differing mass.
Big mountains will have a different signal that is distinct to deep depressions, obviously. But the data also reveals those locations that have discrete rock types and densities.
In the case of Procellarum, the Grail pair sensed an excess of mass stemming from the presence of all the basaltic lava filling the rift valleys.
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The feature stands out in this Mercator map projection of the changes in gravity
Quelle: BBC

Tags: Astronomie 

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Donnerstag, 2. Oktober 2014 - 09:16 Uhr

Astronomie - Unsere Milchstraße aus der Sicht von ISS

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Milky Way Viewed From the International Space Station
NASA astronaut Reid Wiseman captured this image from the International Space Station and posted it to social media on Sept. 28, 2014, writing, "The Milky Way steals the show from Sahara sands that make the Earth glow orange."
Aboard the space station, the six-person Expedition 41 crew is currently preparing for two spacewalks set for Oct. 7 and 15. During the first six-and-a-half-hour spacewalk, slated to begin on Oct. 7 around 8:10 a.m. EDT, Wiseman and European Space Agency astronaut Alexander Gerst will transfer a previously uninstalled pump module from its temporary stowage location to the External Stowage Platform-2. The two spacewalkers also will install the Mobile Transporter Relay Assembly that adds the capability to provide “keep-alive” power to the system that moves the station’s robotic arm between worksites. NASA astronaut Barry Wilmore will join Wiseman for the second Expedition 41 spacewalk on Oct. 15.
Quelle: NASA

Tags: Astronomie 

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Mittwoch, 1. Oktober 2014 - 08:46 Uhr

Raumfahrt - NASA-ISRO Synthetic Aperture Radar (Nisar) Mission 2020

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The NASA-ISRO Synthetic Aperture Radar (NISAR) mission, targeted to launch in 2020, will make global measurements of the causes and consequences of a variety of land surface changes on Earth.

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U.S., India to Collaborate on Mars Exploration, Earth-Observing Mission
In a meeting Tuesday in Toronto, NASA Administrator Charles Bolden and K. Radhakrishnan, chairman of the Indian Space Research Organisation (ISRO), signed two documents to launch a NASA-ISRO satellite mission to observe Earth and establish a pathway for future joint missions to explore Mars.
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NASA Administrator Charles Bolden (left) and Chairman K. Radhakrishnan of the Indian Space Research Organisation signing documents in Toronto on Sept. 30, 2014 to launch a joint Earth-observing satellite mission and establish a pathway for future joint missions to explore Mars.
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While attending the International Astronautical Congress, the two space agency leaders met to discuss and sign a charter that establishes a NASA-ISRO Mars Working Group to investigate enhanced cooperation between the two countries in Mars exploration. They also signed an international agreement that defines how the two agencies will work together on the NASA-ISRO Synthetic Aperture Radar (NISAR) mission, targeted to launch in 2020.
“The signing of these two documents reflects the strong commitment NASA and ISRO have to advancing science and improving life on Earth,” said NASA Administrator Charles Bolden. “This partnership will yield tangible benefits to both our countries and the world.”
The joint Mars Working Group will seek to identify and implement scientific, programmatic and technological goals that NASA and ISRO have in common regarding Mars exploration. The group will meet once a year to plan cooperative activities, including potential NASA-ISRO cooperation on future missions to Mars.
Both agencies have newly arrived spacecraft in Mars orbit. NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft arrived at Mars Sept. 21. MAVEN is the first spacecraft dedicated to exploring the tenuous upper atmosphere of Mars. ISRO’s Mars Orbiter Mission (MOM), India’s first spacecraft launched to Mars, arrived Sept. 23 to study the Martian surface and atmosphere and demonstrate technologies needed for interplanetary missions.
One of the working group’s objectives will be to explore potential coordinated observations and science analysis between MAVEN and MOM, as well as other current and future Mars missions.
“NASA and Indian scientists have a long history of collaboration in space science,” said John Grunsfeld, NASA associate administrator for science. “These new agreements between NASA and ISRO in Earth science and Mars exploration will significantly strengthen our ties and the science that we will be able to produce as a result.”
The joint NISAR Earth-observing mission will make global measurements of the causes and consequences of land surface changes. Potential areas of research include ecosystem disturbances, ice sheet collapse and natural hazards. The NISAR mission is optimized to measure subtle changes of the Earth’s surface associated with motions of the crust and ice surfaces. NISAR will improve our understanding of key impacts of climate change and advance our knowledge of natural hazards.
NISAR will be the first satellite mission to use two different radar frequencies (L-band and S-band) to measure changes in our planet’s surface less than a centimeter across. This allows the mission to observe a wide range of changes, from the flow rates of glaciers and ice sheets to the dynamics of earthquakes and volcanoes.
Under the terms of the new agreement, NASA will provide the mission’s L-band synthetic aperture radar (SAR), a high-rate communication subsystem for science data, GPS receivers, a solid state recorder, and a payload data subsystem. ISRO will provide the spacecraft bus, an S-band SAR, and the launch vehicle and associated launch services.
NASA had been studying concepts for a SAR mission in response to the National Academy of Science’s decadal survey of the agency’s Earth science program in 2007. The agency developed a partnership with ISRO that led to this joint mission. The partnership with India has been key to enabling many of the mission’s science objectives.
NASA’s contribution to NISAR is being managed and implemented by the agency's Jet Propulsion Laboratory (JPL) in Pasadena, California.
NASA and ISRO have been cooperating under the terms of a framework agreement signed in 2008. This cooperation includes a variety of activities in space sciences such as two NASA payloads -- the Mini-Synthetic Aperture Radar (Mini-SAR) and the Moon Mineralogy Mapper -- on ISRO’s Chandrayaan-1 mission to the moon in 2008. During the operational phase of this mission, the Mini-SAR instrument detected ice deposits near the moon’s northern pole.
Quelle: NASA

Tags: Raumfahrt 

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Dienstag, 30. September 2014 - 21:45 Uhr

Astronomie - Spechtel-WE mit Mondsichel

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Am Sonntag-Abend ergab sich einmal wieder schöne Spechtel-Möglichkeit am Südwest-Himmel mit Mondsichel und Arcturus:

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Mondsichel mit Nebelschleier-Effekt

Fotos: ©-hjkc

 


Tags: Astronomie 

2327 Views

Dienstag, 30. September 2014 - 21:23 Uhr

Wissenschaft - Rochester Tarn-Mantel

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'Cloaking' device uses ordinary lenses to hide objects across range of angles

Doctoral student Joseph Choi is pictured with a a multidirectional `perfect paraxial’ cloak using 4 lenses.
Credit: Image courtesy of University of Rochester
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Inspired perhaps by Harry Potter's invisibility cloak, scientists have recently developed several ways -- some simple and some involving new technologies -- to hide objects from view. The latest effort, developed at the University of Rochester, not only overcomes some of the limitations of previous devices, but it uses inexpensive, readily available materials in a novel configuration.
"There've been many high tech approaches to cloaking and the basic idea behind these is to take light and have it pass around something as if it isn't there, often using high-tech or exotic materials," said John Howell, a professor of physics at the University of Rochester. Forgoing the specialized components, Howell and graduate student Joseph Choi developed a combination of four standard lenses that keeps the object hidden as the viewer moves up to several degrees away from the optimal viewing position.
"This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum," said Choi, a PhD student at Rochester's Institute of Optics.
Many cloaking designs work fine when you look at an object straight on, but if you move your viewpoint even a little, the object becomes visible, explains Howell. Choi added that previous cloaking devices can also cause the background to shift drastically, making it obvious that the cloaking device is present.
In order to both cloak an object and leave the background undisturbed, the researchers determined the lens type and power needed, as well as the precise distance to separate the four lenses. To test their device, they placed the cloaked object in front of a grid background. As they looked through the lenses and changed their viewing angle by moving from side to side, the grid shifted accordingly as if the cloaking device was not there. There was no discontinuity in the grid lines behind the cloaked object, compared to the background, and the grid sizes (magnification) matched.
The Rochester Cloak can be scaled up as large as the size of the lenses, allowing fairly large objects to be cloaked. And, unlike some other devices, it's broadband so it works for the whole visible spectrum of light, rather than only for specific frequencies.
Their simple configuration improves on other cloaking devices, but it's not perfect. "This cloak bends light and sends it through the center of the device, so the on-axis region cannot be blocked or cloaked," said Choi. This means that the cloaked region is shaped like a doughnut. He added that they have slightly more complicated designs that solve the problem. Also, the cloak has edge effects, but these can be reduced when sufficiently large lenses are used.
In a new paper submitted to the journal Optics Express Howell and Choi provide a mathematical formalism for this type of cloaking that can work for angles up to 15 degrees, or more. They use a technique called ABCD matrices that describes how light bends when going through lenses, mirrors, or other optical elements.
While their device is not quite like Harry Potter's invisibility cloak, Howell had some thoughts about potential applications, including using cloaking to effectively let a surgeon "look through his hands to what he is actually operating on," he said. The same principles could be applied to a truck to allow drivers to see through blind spots on their vehicles.
Howell became interested in creating simple cloaking devices with off-the-shelf materials while working on a holiday project with his children. Together with his 14 year-old son and Choi, he recently published a paper about some of the possibilities, and also demonstrated simple cloaking with mirrors, like magicians would use, in a brief video.
https://www.youtube.com/watch?v=oJb9RnAVDuE
Quelle: ScienceDaily

Tags: Wissenschaft - Rochester Tarn-Mantel 

2199 Views

Montag, 29. September 2014 - 22:46 Uhr

Raumfahrt - NASA Cold Atom-Labor (CAL) an Bord der Internationalen Raumstation 2016

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Artist’s concept of an atom chip for use by NASA’s Cold Atom Laboratory (CAL) aboard the International Space Station. CAL will use lasers to cool atoms to ultracold temperatures.

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Like dancers in a chorus line, atoms' movements become synchronized when lowered to extremely cold temperatures. To study this bizarre phenomenon, called a Bose-Einstein condensate, researchers need to cool atoms to a temperature just above absolute zero – the point at which atoms have the least energy and are close to motionless.
The goal of NASA's Cold Atom Laboratory (CAL) is to study ultra-cold quantum gases in a facility instrument developed for use on the International Space Station. Scientists will use the facility to explore how differently atoms interact in microgravity when they have almost no motion due to such cold temperatures. With less pull toward the ground from Earth, matter can stay in the form of a Bose Einstein condensate longer, giving researchers the opportunity to observe it better. 
The CAL team announced this week that it has succeeded in producing a Bose-Einstein condensate at NASA's Jet Propulsion Laboratory, a key breakthrough for the instrument leading up to its debut on the space station in late 2016.
A Bose-Einstein condensate is a collection of atoms in a dilute gas that have been lowered to extremely cold temperatures and all occupy the same quantum state, in which all of the atoms have the same energy levels. At a critical temperature, atoms begin to coalesce, overlap and move in synch. The resulting condensate is a new state of matter that behaves like a giant - by atomic standards - wave.
"It’s official. CAL's ground testbed is the coolest spot at NASA's Jet Propulsion Laboratory at 200 nano-Kelvin [200 billionths of 1 Kelvin]," said CAL Project Scientist Rob Thompson at JPL in Pasadena, California. "Achieving Bose-Einstein condensation in our prototype hardware is a crucial step for the mission."
Although these quantum gases had been created before elsewhere on Earth, CAL will explore the condensates in an entirely new regime: the microgravity environment of the space station. It will enable unprecedented research in temperatures colder than any found on Earth.
In the station's microgravity environment, long interaction times and temperatures as low as one picokelvin (one trillionth of one Kelvin, or 293 trillion times less than room temperature) should be achievable. That's colder than anything known in nature, and the experiments with CAL could potentially create the coldest matter ever observed in the universe. These breakthrough temperatures unlock the potential to observe new quantum phenomena and test some of the most fundamental laws of physics. The CAL investigation could advance our knowledge in the development of exquisitely sensitive quantum detectors, which could be used for monitoring the gravity of the Earth and other planetary bodies, or for building advanced navigation devices. 
"Ultra-cold atoms will also be useful for space-based optical clocks that will be future time standards,” Thompson said. 
First observed in 1995, Bose-Einstein condensation has been one of the "hottest" topics in physics ever since. The condensates are different from normal gases; they represent a distinct state of matter that starts to form typically below a millionth of a degree above absolute zero. Familiar concepts of "solid," "liquid," and "gas" no longer apply at such cold temperatures; instead, atoms do bizarre things governed by quantum mechanics, such as behaving as waves and particles at the same time.
CAL researchers used lasers to optically cool atoms of the chemical element rubidium to temperatures almost a million times colder than that of the depths of space. The atoms were then magnetically trapped, and radio waves were used to cool the atoms 100 times lower. The radiofrequency radiation acts like a knife, slicing away the hottest atoms from the trap so that only the coldest remain.
The research is at the point where this process can reliably create a Bose-Einstein condensate in just seconds.
"This was a tremendous accomplishment for the CAL team. It confirms the fidelity of the instrument system design and provides us a facility to perform science and hardware verifications before we get to the space station," said CAL project manager Anita Sengupta of JPL.
JPL is developing the Cold Atom Laboratory sponsored by the International Space Station Program at NASA's Johnson Space Center in Houston. The Space Life and Physical Sciences Division of NASA's Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington manages the Fundamental Physics Program.
While so far CAL researchers have created Bose-Einstein condensates with rubidium atoms, eventually they also will add in potassium.
"The behavior of two condensates mixing together will be fascinating for physicists to observe, especially in space," Sengupta said.
Besides merely creating Bose-Einstein condensates, CAL provides a suite of tools to manipulate and probe these quantum gases in a variety of ways. CAL has a unique role as a facility for the atomic, molecular and optical physics community to study cold atomic physics in microgravity, said David Aveline of JPL, CAL ground testbed lead.
"Instead of a state-of-the-art telescope looking outward into the cosmos, CAL will look inward, exploring physics at the atomic scale," Aveline said.
You may have thought that the coldest place in the universe might be a vast tract of space between distant stars. But in a couple of years, the coldest place we know of will be orbiting our own planet, creating atomic dances to dazzle the scientific imagination. 
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The Cold Atom Laboratory (CAL) conducted its first environmental test series to demonstrate robustness to the launch vehicle environment for flight like electronics, fiber optics, and vacuum system at the JPL Environmental Test Facility.
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This sequence of false-color images shows the formation of a Bose-Einstein condensate in the Cold Atom Laboratory prototype at NASA's Jet Propulsion Laboratory as the temperature gets progressively closer to absolute zero. Red in each figure indicates higher density.
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Members of the Cold Atom Laboratory team at NASA's Jet Propulsion Laboratory are seen here with their ground-based testbed, which can reliably create a Bose-Einstein condensate. Pictured from left to right, Anita Sengupta, Ethan Elliott, Rob Thompson and Markus Krutzik.
Quelle:NASA/JPL-Caltech

Tags: Raumfahrt 

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