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Sonntag, 1. März 2015 - 19:15 Uhr

Raumfahrt - NASA Astronauten Barry Wilmore and Terry Virts vor EVA 31 am Sonntag

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26.02.2015

NASA astronauts Barry Wilmore and Terry Virts ended their spacewalk at 1:34 p.m. EST with the repressurization of the Quest airlock. Wilmore and Virts completed all the scheduled tasks for today. They completed rigging a series of power cables on Pressurized Mating Adapter-2, lubricated the Latching End Effecter of the space station’s Canadarm2 robotic arm, and prepared the Tranquility module for the station’s upcoming reconfiguration in preparation for the arrival of commercial crew vehicles later this decade. They also were able to complete get-ahead work for the installation during Sunday’s spacewalk of the Common Communications for Visiting Vehicles (C2V2) system by pre-staging wire-ties that will be used to secure some 400 feet of cable.
The 6-hour, 43-minute spacewalk was the third for Wilmore and the second for Virts. Wilmore now has spent 19 hours and 58 minutes in the void of space during his three spacewalks. Virts has now spent 13 hours and 24 minutes outside during his two excursions. Crews have now spent a total of 1,165 hours and 51 minutes conducting space station assembly and maintenance during 186 spacewalks.
The duo will venture outside the space station again on Sunday, March 1, to install the C2V2 equipment commercial spacecraft delivering crews to the space station will use to rendezvous and dock with the orbital laboratory. NASA TV coverage will begin at 6 a.m. Sunday ahead of a planned 7:10 a.m. start time for the spacewalk.
Quelle: NASA
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Update: 28.02.2015
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NASA 'go' for Sunday spacewalk outside ISS

NASA today confirmed plans for astronauts to proceed Sunday morning with a third spacewalk in just over a week outside the International Space Station.
Engineers determined there was no danger posed by the small amount of water astronaut Terry Virts reported floating in his helmet at the conclusion of the second spacewalk in the series on Wednesday.
The presence of water in a spacewalker's helmet became a major concern in 2013 when a significant leak threatened to drown Italian spacewalker Luca Parmitano.
NASA believes the estimated 15 milliliters of water Virts reported is the product of a known issue with his spacesuit that is unrelated to the cause of the leak Parmitano survived.
Virts and fellow NASA astronaut Barry "Butch Wilmore" on Sunday plan to continue rigging hundreds of feet of cables and install communications antennas, steps toward the outpost welcoming commercial crew capsules in the next few years.
The planned six-and-a-half-hour spacewalk is expected to start at 7:10 a.m. EST Sunday. Follow live NASA TV coverage starting at 6 a.m.
Quelle: Florida Today
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NASA OKs Sunday spacewalk despite water leak in helmet

Left to Right: NASA astronaut Terry Virts, Italian astronaut Samantha Cristoforetti and cosmonaut Anton Shkaplerov inspect Virts' spacesuit helmet after it leaked a small amount of water during a spacewalk Wednesday, Feb. 25, 2015. (PHOTO/NASA TV)
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CAPE CANAVERAL -- 
Astronauts on the International Space Station will head out for another spacewalk this weekend despite a water leak in one astronaut's helmet Wednesday.
NASA on Friday cleared astronaut Terry Virts' spacesuit for Sunday's spacewalk, the last of three to route hundreds of feet of cable needed for the new, American-made spacecraft set to fly to the space station starting in 2017.
At the end of  Wednesday's spacewalk with fellow astronaut Butch Wilmore, a small amount of water leaked into Virts' helmet.
NASA said Virts was never in any danger Wednesday, but engineers spent two days investigating the leak. Another astronaut almost drowned in 2013 when his helmet flooded during a spacewalk.
NASA said it now believes it understands the quirks with Virts' spacesuit and helmet, and that they are safe to use on Sunday.
Quelle: NEWS13
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Update: 1.03.2015 
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After a spectacular run of two EVAs, lasting a cumulative 13 hours and 24 minutes, over the last week, Expedition 42 astronauts Barry “Butch” Wilmore and Terry Virts will venture outside the International Space Station (ISS) for the third and final time tomorrow (Sunday). Scheduled to run for six hours and 45 minutes, EVA-31 will install the expansive Common Communications for Visiting Vehicles (C2V2) infrastructure, providing standardized communications between the ISS and future visiting vehicles—including Boeing’s CST-100 and SpaceX’s Dragon V-2 piloted craft—with a common data link for exchanging audio, video, and telemetry at varying rates and communications ranges. For unpiloted visiting vehicles, this will include trajectory and spacecraft health data, whilst for the piloted craft it will also feature a two-way audio capability. When the C2V2 hardware is fully operational, it will operate for up to 13 years, throughout the expected remainder of the station’s lifetime, and consolidate ISS-based communications, save weight and volume, and greatly simplify logistics for co-ordinating the arrival and departure of all visiting vehicles.
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Frams: NASA-TV
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NASA astronauts Terry Virts and Barry Wilmore ended their spacewalk at 12:30 p.m. EST with the repressurization of the Quest airlock. Virts and Wilmore completed installing 400 feet of cable and several antennas associated with the Common Communications for Visiting Vehicles system known as C2V2. Boeing’s Crew Transportation System (CST)-100 and the SpaceX Crew Dragon will use the system in the coming years to rendezvous with the orbital laboratory and deliver crews to the space station.

Tags: Raumfahrt 

1737 Views

Sonntag, 1. März 2015 - 10:46 Uhr

Astronomie - Massiven Meteoritenkrater in der kanadischen Arktis gefunden

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A river gorge cut into the tundra of northwestern Victoria Island shows steeply tilted sedimentary rock strata. These deformed beds represent the central uplift caused by rebound after the meteor impact that formed the Prince Albert crater.

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Researchers in Canada's western Arctic have found evidence of a crater that formed when a huge meteorite slammed into Earth millions of years ago.
Measuring about 15 miles (25 kilometers) across, the formation was named the Prince Albert impact crater after the peninsula where it was discovered. Researchers don't know exactly when it was created, but evidence suggests the crater is between 130 million and 350 million years old, according to a statement from the University of Saskatchewan.
Meteors are fragments of asteroids or comets that enter Earth's atmosphere at high speeds; most are small, some as tiny as a grain of sand, so they discintegrate in the air, and only rarely are they large enough to make it to Earth's surface. When meteors slam into Earth, they are called meteorites.
A team of geologists spotted this newly identified meteorite crater while surveying the region for possible energy and mineral resources. They were initially intrigued by steeply tilted strata visible in river gorges and other features in the flat tundra of northwestern Victoria Island. 
"Unless you recognized the telltale clues, you wouldn't know what you were looking at," researcher Brian Pratt explained in the statement. "You might see a bunch of broken rocks and wonder how they got there, but we found abundant shatter cones."
Shatter cones are surface features with distinctive wavy patterns that are known to be created only by the tremendous force of a meteorite impact or an underground nuclear explosion. What's more, Pratt said his map showed that the feature is circular, which is characteristic of impact craters.
"Impact craters like this give us clues into how the Earth's crust is recycled and the speed of erosion, and may be implicated in episodes of widespread extinction of animals in the geological past," Pratt said. "It's an exciting discovery."
There are about 180 known impact craters on Earth. Geologists think they would find countless more if plate shifting, volcanic activity and erosion didn't hide the evidence of most ancient impacts.
Earlier this summer, researchers in Greenland documented possibly the oldest and largest meteorite crater ever found on Earth. The crater, estimated to be 3 billion years old, currently measures about 62 miles (100 km) across. But the researchers believe its width before erosion was likely more than 310 miles (500 km) — much bigger than the largest visible crater, the 2-billion-year-old Vredefort crater in South Africa, which measures 186 miles (300 km) across.
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This photo is looking down on a bed showing interfering shatter cones radiating downwards (away from the strike). The shatter cone surface consists of radiating ridges and grooves. The Swiss army knife is for scale.
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Researchers in Canada's western Arctic have found evidence of a crater that formed when a huge meteor slammed into Earth millions of years ago. 
Here, Geological Survey of Canada geologist Keith Dewing examines shatter cones and takes notes at the newly discovered Prince Albert impact crater, as it has been called, located in northwestern Victoria Island in the western Arctic.
Quelle: livescience

Tags: Astronomie 

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Sonntag, 1. März 2015 - 10:35 Uhr

Astronomie - Bestätigt: Meteorit verursachte schwedischen See

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A photo taken through a microscope of shocked quartz from the Hummeln crater in Sweden.
Credit: Ludovic Ferrière, NHM Vienna
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After two centuries of arguing about its origin, scientists have finally confirmed that Hummeln Lake in southern Sweden is an impact crater.
Hummeln Lake's rounded shoreline first drew interest from scientists as far back as the 1820s, but it wasn't identified as a possible impact crater until the 1960s, said Carl Alwmark, lead author of the new study and a geologist at Lund University in Sweden. Until then, geoscientists thought the circular structure, which is 0.7 miles (1.2 kilometers) wide and 525 feet (160 meters) deep, was an extinct volcano. Now researchers think the crater resulted from a space rock that was likely about 325 feet to 490 feet (100 to 150 m) in diameter, Alwmark said.
Alwmark and his colleagues recently found the telltale clues that confirm an impact carved out the Hummeln crater. Their findings were published Feb. 18 in the journal Geology.
The key evidence includes shocked quartz from a layer of breccia at the lake. A breccia is a type of rock made up of angular fragments of other rocks held together by a finer-grained medium, similar to natural cement. Breccia forms in many settings on Earth, but the shocked features in the quartz minerals are created only under the intense pressures caused by meteorite impacts.
Others have searched before for similar features, but Alwmark hit the jackpot while working at the nearby Siljan crater, one of the largest on Earth. Hummeln Lake is a popular tourist stop, with rental cabins surrounded by silver birch trees, and Alwmark said he popped in and picked up some rocks on the drive between craters.
"These shocked features are not very common, and we got lucky," he told Live Science.
The crash site adds to the growing body of evidence that meteorites bombarded Earth during the Late Ordovician Period, Alwmark said. Scientists think that a wave of space debris slammed into the Earth after a huge smashup between two large bodies out in the asteroid belt some 470 million years ago. (One of the crash victims was the source of all L-chondrite meteorites.)
Researchers think about 100 times as many meteorites fell on Earth during the Ordovician compared with today. However, although many small meteorites and micrometeorites dated to the Late Ordovician have been found, scientists have only discovered about a dozen large craters. These include the unusual Lockne-Malingen double crater in northern Sweden and the Ames Crater in Oklahoma. The growing list of craters supports models that suggest larger rocks also pummeled the planet.
"There are too many craters at this point for it just to be a coincidence," Alwmark said. "If we start finding even more of these larger craters, then you should start speculating about whether this [bombardment] could have had a profound impact on the evolution of Earth's biology," he said.
Shallow seas covered much of the planet in the Late Ordovician, and the seafloor sediments that buried these craters protected the formations for millennia. Fossils from fish that patrolled the seas have helped researchers precisely date the ancient structures.
Quelle: livescience

Tags: Astronomie 

1943 Views

Samstag, 28. Februar 2015 - 23:15 Uhr

Raumfahrt - Erfolgreicher Start von Sounding Rocket Cryofenix auf Esrange Space Center

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SUCCESSFUL LAUNCH OF CRYOGENIC LIQUID EXPERIMENT

For the first time in Europe, an experiment studying the behavior of liquid hydrogen in microgravity was carried out in space.

On SunCryofenix launch. Photo Anders Aberg, SSC Vidsel Test Rangeday 22th of February at 07.52 UTC, the sounding rocket Cryofenix was launched from SSC's launching facility Esrange Space Center using a two-stage VSB30 rocket.
Cryofenix reached an apogee of 265 km and the payload spent 6 minutes in microgravity.
The experiment Cryofenix studied the behavior of cryogenic liquids as part of the French space agency CNES' launcher technology program. Cryofenix completed the validation of various simulations of the behavior of fluids in the ballistic phase, which for ten years have been developed by Air Liquide Advanced Technologies (ALAT) and CNES within the framework of the technology research program.
SSC has been subcontractor to Air Liquide Advanced Technologies and was responsible for the development of two new complex modules; a control module for the main experiment module developed by ALAT and a thruster module to apply a controlled linear acceleration to the payload in flight. SSC also delivered the launch service from Esrange Space Center.
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Quelle: SSC

Tags: Raumfahrt 

2010 Views

Samstag, 28. Februar 2015 - 18:33 Uhr

Raumfahrt - ISRO startet (GSLV) MK III mit Polar Satellite Launch Vehicle (PSLV) C-27 im Dezember 2016

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TIRUNELVELI: Geosynchronous Satellite Launch Vehicle (GSLV) MK III will be launched by December 2016 while the Polar Satellite Launch Vehicle (PSLV) C-27, carrying the Indian Regional Navigational Satellite System (IRNSS -1D), is scheduled to be launched on March 9, said AS Kiran Kumar, chairman, Indian Space Research Organization (ISRO) and Space Commission.
Kiran Kumar is on an official visit to ISRO Propulsion Complex (IPRC), Mahendragiri, Tirunelveli district.
He saw one of the qualification tests necessary for the High Power Cryogenic Engine particular to GSLV MK III, along with IPRC director Karthikesan. The qualification test was successful, said Kiran Kumar here on Friday.
Speaking to reporters later, Kiran Kumar said, “Full-fledged activities essential for launching the GSLV MK III are carried out simultaneously at various ISRO centres including IPRC Mahendragiri.
By December 2016 we will launch the full congregation of GSLV MK with high power cryogenic engine.”
He added that, “PSLV C-27 rocket, carrying IRNSS-1D, is scheduled to be launched on March 9. While IRNSS-1D is the fourth satellite of the seven part system, all the remaining three satellites will be launched within this year.
Besides, we will also launch GSLV D6 at the end July 2015.”
Quelle: The New Indian Express

Tags: Raumfahrt 

1650 Views

Samstag, 28. Februar 2015 - 17:30 Uhr

Raumfahrt - Offenbar Explosion von 20-jährigen Militär Wettersatelliten im Orbit

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WASHINGTON — A 20-year-old military weather satellite apparently exploded in orbit Feb. 3 following what the U.S. Air Force described as a sudden temperature spike.
The “catastrophic event” produced 43 pieces of space debris, according to Air Force Space Command, which disclosed the loss of the satellite Feb. 27 in response to questions from SpaceNews.
The satellite, Defense Meteorological Satellite Program Flight 13, was the oldest continuously operational satellite in the DMSP weather constellation.
Launched in 1995, DMSP-F13 provided thousands of hours of weather imagery to Air Force and Navy forecasters before transitioning to a backup role in 2006. The Air Force said its sudden loss would have minimal impact.
“Because this satellite was no longer used by the National Weather Service or the Air Force Weather Agency, the impact of the loss of this satellite is minimal,” the Air Force said. “We anticipate real-time weather data for tactical users will be slightly reduced without this satellite, but its data was not being used for weather forecast modeling.”
The Air Force still has six DMSP satellites in service following the launch last April of DMSP-F19. A seventh satellite, DMSP-F20, was under consideration for a 2016 launch as recently as November.
Air Force Space Command said DMSP-F13’s power subsystem experienced “a sudden spike in temperature” followed by “an unrecoverable loss of attitude control.” As DMSP operators were deciding to “render the vehicle safe” the Joint Space Operations Center at Vandenberg Air Force Base, California, identified a debris field near the satellite.
The Air Force said it is continuing to track the debris and will issue conjunction warnings if necessary.
“While the initial response is complete, JSpOC personnel will continue to assess this event to learn more about what happened and what it will mean for users within this orbit,” said Air Force Col. John Giles, the Joint Space Operations Center’s director.
DMSP-F13 flew in a 800-kilometer sun-synchronous polar orbit popular for weather and spy satellites.
The first public indication of a problem with DMSP-F13 came from T.S. Kelso, a senior research astrodynamicist for Analytical Graphics’ Center for Space Standards and Innovation in Colorado Springs, Colorado, who noted Feb. 25 that there had been “another debris event with 26 new pieces” in addition to five previously cataloged  DMSP-F13 objects.
- See more at: http://spacenews.com/20-year-old-military-weather-satellite-apparently-exploded-in-orbit/#sthash.P5uLtni1.dpuf
Quelle: SN

Tags: Raumfahrt 

1765 Views

Freitag, 27. Februar 2015 - 21:49 Uhr

Science Fiction - Der "Star-Trek"-Darsteller Leonard Nimoy (Mr.Spock)ist im Alter von 83 Jahren verstorben

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Leonard Nimoy ist gestorben
Der "Star-Trek"-Darsteller Leonard Nimoy ist tot. Der Schauspieler starb im Alter von 83 Jahren in Los Angeles. Bekannt wurde er mit seiner Rolle als Mr. Spock.
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Der US-Schauspieler Leonard Nimoy ist im Alter von 83 Jahren gestorben. Vor allem durch die Rolle als Halb-Vulkanier Mr. Spock in der Fernsehserie Star Trek (Raumschiff Enterprise) ist er weltberühmt geworden. Am Freitag starb Nimoy in Los Angeles an einer Lungenerkrankung. Vor einem Jahr hatte er die Erkrankung öffentlich gemacht, die er auf jahrelanges Rauchen zurückführte.
Der Sohn jüdisch-orthodoxer Einwanderer aus der Ukraine begann seine Karriere als Kinderdarsteller in seiner Geburtsstadt Boston. Er spielte in zahlreichen Filmen und TV-Serien mit und arbeitete auch als Regisseur, Produzent und Fotograf, zudem verfasste er Gedichte.
Bekannt wurde Nimoy allerdings vor allem mit seiner Rolle als Mr. Spock, dem ersten Offizier auf dem Raumschiff Enterprise. Kultstatus erlangten seine Ein-Satz-Analysen und sein mit erhobener Augenbraue vorgetragenes "Faszinierend".
Lange Zeit tat Nimoy sich schwer damit, nur auf diese eine Rolle reduziert zu werden. Seine erste Autobiografie aus dem Jahr 1977 trug den Titel: Ich bin nicht Spock. Später fand er sich damit ab. 
"Live long and prosper"
Seine zweite Autobiografie aus dem Jahr 1995 hieß dann auch Ich bin Spock. "Wie viele Schauspieler können schon von sich behaupten, dass sie über Jahrzehnte hinweg mit einer bestimmten Rolle identifiziert werden?" Das sei eine ganz besondere Ehre. "Zum Glück sind die Witze über meine Ohren weniger geworden." Seine Tweets beendete er immer mit dem Kürzel LLAP, was für den vulkanischen Gruß "live long and prosper" steht. 
Auch politisch war Nimoy engagiert. Im Nahost-Konflikt sprach er sich 2011 für eine Zwei-Staaten-Lösung aus. In einem Offenen Brief verwies er unter anderem auf die Star-Trek-Episode Let That Be Your Last Battlefield (Bele jagt Lokai, 1969), in der sich ein schwarz-weißer Mutant vom Planeten Cheron und ein weiß-schwarzer Gegenspieler im Namen ihrer historischen Identität bekämpfen. Der Vergleich solle "die sehr realen Probleme, die Israelis und Palästinenser trennen, nicht herunterspielen", sagte Nimoy. Das fiktive Drama zeige aber, dass ein Mythos zur Falle werden könne. Ein Kompromiss müsse durch Landtausch zu "zwei Staaten für zwei Nationen" führen; der von Palästinensern bewohnte Teil Jerusalems solle Hauptstadt Palästinas werden.
Sein Schauspiel-Kollege William Shatner alias Captain Kirk, fast auf den Tag genauso alt wie Nimoy, verabschiedete sich mit den Worten: "Ich habe ihn wie einen Bruder geliebt. Wir alle werden seinen Humor, seine Begabung und seine Fähigkeit zu lieben vermissen."  
Quelle: ZEIT
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Tags: Science 

1710 Views

Freitag, 27. Februar 2015 - 10:43 Uhr

Raumfahrt - Start von Soyuz-2.1a Trägerrakete mit militärischen Satelliten für heute geplant

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The launch of the Soyuz-2.1a carrier rocket with military spacecraft is planned for today, Defense Ministry spokesman Alexey Zolotukhin told TASS on Friday.
"A decision will be made at the government commission session that will take place today at the cosmodrome," Zolotukhin said. The carrier rocket will be launched from the Plesetsk cosmodrome in the Arkhangelsk Region.
The three-stage middle-class liquid-propelled rocket was manufactured at the Samara-based Progress space rocket center. The start mass of the carrier is 311.7 tons. The rocket is capable of carrying around 7,480 kilograms of cargo into orbit. The rocket was modernized with the principally new digital control system with modern Russian element base.
The next launch of the Soyuz-2.1a rocket carrier is planned for April 28. The rocket carrier will be launched from the Baikonur cosmodrome in Kazakhstan.
Quelle: TASS

Tags: Raumfahrt 

1865 Views

Freitag, 27. Februar 2015 - 10:20 Uhr

Mars-Chroniken - Könnten Wassermoleküle des Mars auf die Erde gelangt sein?

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Die HRSC-Kamera an Bord der Mars Express-Raumsonde hat dieses Bild gegen den Marshorizont aber in erster Linie deshalb aufgenommen, weil es die Struktur der Marsatmosphäre sichtbar macht. Deutlich ist darauf zu erkennen, wie sich die untere, dichtere Atmosphäre von der Stratosphäre abhebt.

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Die HRSC-Kamera an Bord der Sonde Mars Express liefert seit Januar 2004 hochaufgelöste Aufnahmen der Marsoberfläche - in Farbe und 3D. Wir veröffentlichen diese Bilder monatlich auf unserer Sonderseite über die Mission Mars Express. Immer wieder erreichen uns Fragen zu diesen Bildern und den darauf zu sehenden geologischen Beschaffenheiten oder auch zum Thema Mars allgemein. Eine besonders interessante Frage beantwortet Ulrich Köhler aus dem DLR-Institut für Planetenforschung in diesem Blogpost ausführlich.
Frage: Könnte es möglich sein, dass nach dem Zusammenbruch der Marsatmosphäre das gasförmig gewordene Wasser durch Gravitation auf die Erde gelange?
Im Prinzip: ja. Allerdings müssen ein paar Einschränkungen gemacht werden. Zunächst einmal ist nicht ganz klar, was mit dem "Zusammenbruch der Marsatmosphäre" gemeint ist. Die gegenwärtige Marsatmosphäre ist zwar im Vergleich zur Erdatmosphäre wesentlich dünner (je nach Höhenlage 1/100 bis 1/150 des Gasdrucks der Erdatmosphäre), aber sie ist doch relativ stabil. Ein Prozess, der zu etwas Ähnlichem wie dem "Zusammenbruch" der Marsatmosphäre führen könnte, wäre ein Einschlag eines sehr großen Asteroiden, der durch die Marsatmosphäre rauscht, einschlägt, und durch die Folgeprozesse das vor dem Einschlag in die Atmosphäre gerissene "Loch" noch vergrößern würde: Die Atmosphäre wäre bei einem solchen "Durchschuss", der mit Geschwindigkeiten von mehreren zehntausend Kilometern pro Stunde stattfinden würde, gewissermaßen dort "erodiert". Für den kompletten Zusammenbruch der Marsatmosphäre wäre eine Kollision mit einem vielleicht 500 bis 1000 Kilometer großen Asteroiden erforderlich, das müsste man aber nochmal genauer modellieren.
Ganz verschwinden würde sie also selbst infolge einer sehr großen Kollision mit einem Asteroiden noch nicht - aber ausgedünnt. Und da gegenwärtig keine Gase in der Menge im Inneren des Mars produziert und durch Vulkane der Atmosphäre zugeführt würden, wie durch solch ein Ereignis verloren gehen würden, wäre die Atmosphäre nachher dünner als vorher. Aber es ist zum einen kein Asteroid dieser Größenordnung bekannt, der sich auf Kollisionskurs mit dem Mars befände, und es ist auch kein Prozess im Gange, der die Marsatmosphäre zusammenbrechen lassen würde.
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HRSC-Kamera von Mars-Express
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Trotzdem: Wären bei einem solchen Ereignis Wassermoleküle mit ins All gerissen worden, hätten also "Fluchtgeschwindigkeit" erreicht und wären dadurch der Anziehungskraft des Mars entzogen. Dann können solche Moleküle theoretisch auch tiefer ins innere Sonnensystem driften und irgendwann von der Anziehungskraft der Erde "eingefangen" werden. Dieses "Marswasser" würde allerdings zum überwiegenden Teil von der Marsoberfläche stammen (Eisvorkommen am Nord- oder Südpol), oder von Eisschichten unter der Marsoberfläche. Die heutige Marsatmosphäre enthält nur 210 ppm (Teile pro Million Teilchen) Wassermoleküle. Das ist vernachlässigbar. Es wären also in erster Linie Moleküle, Atome oder Ionen - entsprechend der Häufigkeit, mit der sie in der Marsatmosphäre vorkommen - von Kohlendioxid (96 Prozent), Stickstoff (1,9 Prozent), Argon (1,9 Prozent), Sauerstoff (0,15 Prozent) und Kohlenmonoxid (0,06 Prozent) - erst dann kämen Wassermoleküle.
Wäre es tatsächlich zu einem Transfer von Wassermolekülen vom Mars zur Erde gekommen, so wären diese Moleküle zwar theoretisch aufgrund ihrer etwas anderen Isotopenzusammensetzung (das Verhältnis verschiedener "Sorten" der im Wassermolekül gebunden Wasserstoff- und Sauerstoffatome) nachweisbar und als "marsianisch" identifizierbar. Da es aber nur sehr, sehr, sehr, sehr wenige Atome sein dürften, die es bis zur Erde geschafft haben, dürfte ein Nachweis mit heutigen Analyseverfahren nahezu unmöglich sein.
Etwas anders verhält es sich mit winzigen Gaseinschlüssen in Meteoriten: Wir wissen von einigen Meteoriten, dass sie vom Mars stammen müssen, weil sie winzige Gaseinschlüsse enthalten, in denen das Edelgas Argon in der typischen Konzentration der von Raumsonden gemessenen Marsatmosphäre vorkommt. Das ist ziemlich zweifelsfrei.
Quelle: DLR

Tags: Mars-Chroniken 

1850 Views

Freitag, 27. Februar 2015 - 09:43 Uhr

Raumfahrt - Erste Erde Aufnahme aus dem All durch V-2 Start auf White Sands Missile Range

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First photo of Earth from space was from deadly rocket

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(Image: Johns Hopkins University via Bloomsbury Auctions)
We have the world's first ballistic missile to thank for taking the first ever photograph of Earth from space.
This scratchy image is an original print of the photo, taken in 1946 by a camera in the nose of a V-2 rocket more than 100 kilometres above our planet's surface. The 35-millimetre negative was retrieved from the remains of the camera after the rocket smashed back to Earth.
The rocket was designed by rocketry pioneer Wernher von Braun for a very different purpose. In 1944, German V-2s rained down on western Europe, terrifying civilians and killing thousands. But they were also a technological triumph: the first things made by humans to travel outside Earth's atmosphere.
After the war, unused V-2s were claimed by the victorious allies. Most were used to develop the rockets that would eventually propel US and Soviet satellites and humans into space – and to threaten nuclear war. The rocket that took this photo was part of the US haul, launched from White Sands Missile Range in New Mexico on 24 October 1946.
The original print of the photograph was auctioned today by Dreweatts & Bloomsbury in London. It was part of a collection of original early space photography from the golden age of the space race and fetched £1400.
Quelle: NewScientist

Tags: Raumfahrt 

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