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Sonntag, 14. Oktober 2012 - 18:55 Uhr

Raumfahrt - Erfolgreicher Start von Proton-M mit US-Telekom-Satelliten

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Russia’s Proton-M carrier rocket with a US telecoms satellite, Intelsat-23, blasted off on Sunday from the Baikonur space center in Kazakhstan, a Russian Federal Space Agency spokesman said.

“Proton-M with the Intelsat-23 satellite was launched at the designated time - 12:37 p.m. Moscow time [8:27 GMT]. The separation of the spacecraft from the Briz-M upper stage is scheduled for 22:07 p.m. Moscow time [18:07 GMT],” the spokesman said.

The launch was initially scheduled for August 23, but was postponed because of a failed satellite launch earlier that month, when two telecommunications satellites were lost due to a failure in the Russian Proton-M rocket's upper stage.

Intelsat-23 has been built by Orbital Sciences Corporation for Intelsat Ltd., which operates the world's most extensive satellite network, comprising over 50 satellites.

The satellite is equipped with 24 C-band and 15 Ku-band transponders and will provide telecommunications services to customers in North and Latin America, Western Europe, Africa and some islands in the Pacific and Atlantic Oceans.

The launch of the Proton-M is conducted under a contract concluded by International Launch Services Inc. (ILS), which is owned by the Khrunichev Center, RSC Energia and US firm Space Transport Inc.

Quelle: Roscosmos


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Sonntag, 14. Oktober 2012 - 18:42 Uhr

Raumfahrt - Erfolgreicher Start von Long March 2C

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The Long March 2C carrier rocket carrying two satellites blasts off from the launch pad at the Taiyuan Satellite Launch Center in Taiyuan, capital of north China's Shanxi Province, Oct. 14, 2012. Satellite A and Satellite B, which form Shijian (practice)-9 satellites, successfully entered preset orbits on Sunday morning. (Xinhua/Yan Yan)

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China successfully launched the Practice-9 A and Practice-9 B satellites into space at 11:25 a.m. Sunday, the Taiyuan Satellite Launch Center said.

The satellites, launched from the center in north China's Shanxi Province, were boosted by a Long March-2C carrier rocket and sent into a predetermined orbit.

The Practice-9 A and B are the first in a series of civilian satellites designed for technological experimentation.

Developed by an affiliate company of the China Aerospace Science and Technology Corporation, the satellites will be used to experiment with domestically developed components, satellite formations and inter-satellite measurement, the center said.

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The Long March 2C carrier rocket carrying two satellites blasts off from the launch pad at the Taiyuan Satellite Launch Center in Taiyuan, capital of north China's Shanxi Province, Oct. 14, 2012. Satellite A and Satellite B, which form Shijian (practice)-9 satellites, successfully entered preset orbits on Sunday morning. (Xinhua/Yan Yan)


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Sonntag, 14. Oktober 2012 - 18:30 Uhr

Raumfahrt - Space-Shuttle Endeavour last Road-Trip

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A space shuttle is set to make its first-ever parade through city streets this Friday and Saturday (Oct. 12 and 13), and anyone in the Los Angeles area can get a front-row seat.
The retired shuttle Endeavour, which made its last trip to space in May 2011, is soon set to join the ranks of museum displays at the California Science Center (CSC).
The orbiter flew to California in September from its previous home base at the Kennedy Space Center in Cape Canaveral, Fla. Since then, it's been waiting at the Los Angeles International Airport (LAX) until the museum is ready to receive it. The final leg of its journey is set for later this week.
The space shuttle is due to make the 12-mile (19 kilometer) trip from LAX to the CSC during a two-day parade beginning before dawn on Friday morning. Over the course of its parade through the streets of Inglewood and Los Angeles, Endeavour will stop for celebrations outside The Forum, the former L.A. Lakers arena, and at a street intersection where "Fame" actress Debbie Allen has choreographed a tribute performance.
Endeavour will roll through the streets atop a special NASA transporter pulled by four computer-controlled vehicles. For a small part of its trip, the shuttle will be towed by a Toyota Tundra pickup truck. The whole progression is being dubbed "Mission 26: The Big Endeavour," as the shuttle previously made 25 missions to orbit.
Public viewing will be possible only from select locations, as safety and logistics concerns have forced the police to shut down many streets and sidewalks.
The giant orbiter, which has a 78-foot (24 meter) wingspan and a 58-foot-tall (18 m) tail, will be a tight squeeze through many roads, where several hundred trees have had to be felled in preparation for the shuttle's passage. (The CSC Foundation is sponsoring the replanting of up to four trees in place of each downed one, as well as two years of tree maintenance.)
This map shows the 12-mile route the space shuttle Endeavour will take from Los Angeles International Airport (lower left) to the California Science Center on Oct. 12-13, 2012.
CREDIT: California Science Center
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Here's an outline of Endeavour's expected route:
Friday (Oct. 11), 2 a.m. PDT: Endeavour to depart LAX
Friday, mid-morning: Endeavour will take Westchester Boulevard to Sepulveda, where it will stop for about nine hours for power lines to be raised.
Friday, afternoon: Endeavour will continue down Manchester Boulevard, crossing into Inglewood, where it will stop for another six hours for more power line work.
Friday, overnight: Endeavour will cross the 405 freeway.
Saturday, 8 a.m. PDT: Endeavour will pass by Inglewood City Hall, where the public can see it, and continue to The Forum for a public ceremony.
Saturday, 2 p.m. PDT: Endeavour will stop at Crenshaw Boulevard and Martin Luther King, Jr. Boulevard for the Debbie Allen production, which will also be open to the public.
Saturday, afternoon: Endeavour will take King to Bill Robertson Lane and then turn left into Exposition Park.
Saturday, 9 p.m. PDT: Endeavour is expected to arrive at the California Science Center, where the public can view it roll in.
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Update-Update-Update : 15.45 MESZ
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The space shuttle Endeavour has left the grounds of the Los Angeles International Airport and is now on city streets, heading east toward Inglewood.
The massive spacecraft, rolling at under 2 mph, left the airport at 2 a.m. exactly. "Right on time, it just cleared the gates," said airport spokeswoman Nancy Castles. 
The weathered shuttle -- its blemishes easy to see -- took up two of the four lanes of the road as it rolled down Northside Parkway, and a handful of vehicles led the procession, including a truck that had a U.S. flag fluttering behind it.
At the first sight of Endeavour, scores of onlookers waiting patiently on city streets began running on Westchester Parkway, some with camera tripods in tow, snapping photos furiously. 
They had been waiting hours in the dark, some perched on top of car roofs, and others on ladders and step stools yearning, in the crisp autumn darkness, for their first glimpse of America's last space shuttle.
About 100 people whooped and hollered from the corner of Westchester Parkway and McConnell Avenue.
"Welcome Endeavour! You're ours now!" a young woman wearing a lavender jacket shouted before melting back into the crowd.
Half a dozen firefighters on top of their engine snapped photos on Westchester. A woman wearing furry tie-dyed legwarmers gazed at the shuttle, wearing a bike helmet with U.S. and California flags sticking out.
People on sidewalks scrambled to follow the shuttle as it moved to the east. The sides of the road were littered with abandoned bicycles as shuttle fans rushed to follow Endeavour just a little bit more. 
Los Angeles Police Capt. Jon Peters stopped in front of a couple marveling at Endeavour, and paused for a moment as it negotiated a turn around a tree -- a delay long enough for spectators to catch up.
"You see that guy in the front there, with the joystick? Amazing. Tell your kids to stay on those video games," Peters said.
Earlier, the mood was anxious, if a bit weary, as the spectators stood in the cool night air, nearby light stands creating patches of brightness in the darkness. A few bicyclists sauntered down the pathway that the still-distant shuttle would take, prompting a couple of yells from officials in hardhats.
Others lingered at a corner, not quite sure if or when they would be told to leave. 
Earlier in the night, TV trucks and camera crews outnumbered pedestrians at the first viewing spot along the shuttle's 12-mile trek. "I'm surprised there isn't a mob of people around here," said David Loudenback, 66, a retired engineer who lives a mile down the road. He said that he is no night owl, but that he decided the spectacle was worth a little lost sleep. "This is one of the little perks of living by the airport, said Loudenback, who is familiar with the nightly hum of jet engines passing over his home.
He and a handful of others continued to look over their shoulders for the first sign of authorities.
There were soft groans when a tram full of nearly 50 uniformed officers pulled up. "I feel like I'm in 'I, Robot,'" said Helen Pans, 45, of Playa del Rey. Pans had just been shooed down the road by a police officer. "They were really touting it when Endeavour was flying by, saying it would be a parade, and now all of a sudden you've got people coming up to you telling you you have to leave," she said.
Pans said even as a child, she was fascinated by the space shuttles. She said she clearly remembers the day of the Challenger disaster. She was working on Capitol Hill at the time, and she recalled her entire office crowding around a tiny screen after the disaster. "People were in tears," she said.
Endeavour, which was built to replace Challenger, landed for the final time at Los Angeles International Airport on Sept. 21. Pans was at the Grove at the time, and sprinted to the top of the parking garage to catch a glimpse.
"I've always wanted to see a takeoff or see a landing," she said. Perhaps, she added, this would be good enough.
For Ali Hart, though, the spectacle was only worth so much. Her brother, Nathan, had roused her from bed before midnight and persuaded her to come with him to try to see the shuttle's passage. Their parents had been at the site of Endeavour's first landing at Edwards Air Force Base, just yards away from President Reagan. 
"I thought it would be cool to see it," said Hart, 21. "But I'm not going to chase it all over L.A."
Over the next two days, the 170,000-pound shuttle is expected to travel at no more than 2 mph along the 12-mile route that includes Westchester Parkway, La Tijera Boulevard, Crenshaw Boulevard and Martin Luther King Jr. Boulevard. The shuttle is moved by four computer-controlled transporters that will help it negotiate complex turns and avoid streetside obstacles.
At points along the way, the space vehicle will be inches away from buildings and protrude onto driveways and sidewalks. Because of the enormous weight of the shuttle, thousands of heavy steel plates have been used to reinforce city streets.
Endeavour is scheduled to arrive at the California Science Center by 9 p.m. Saturday.
En route, the public can see the shuttle on Friday at a number of public viewing areas along Manchester Boulevard in Inglewood, including Isis, Hindry and Glasgow avenues as well as La Cienega Boulevard.
On Saturday, there will also be several designated public viewing areas, including the Forum in Inglewood, the intersection of Crenshaw and Martin Luther King Jr. Boulevard, and certain parking lots in Exposition Park.
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Update: 14.10.2012
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Samstag, 13. Oktober 2012 - 23:16 Uhr

Planet Erde - In zehn Tagen um die Welt: Klimaforschung mit HALO

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Das jüngst im August an die Wissenschaft übergebene Forschungsflugzeug HALO (High Altitude and Long Range Research Aircraft) ist von seiner ersten weltumspannenden Mission zurückgekehrt. Für die Überprüfung globaler Klimamodelle absolvierte HALO in nur zehn Tagen Messflüge zwischen der Nordpolarregion und der Südpolarregion, vom norwegischen Spitzbergen bis zum Rand des antarktischen Kontinents.

Unter Federführung des Deutschen Zentrums für Luft- und Raumfahrt (DLR) untersuchte ein insgesamt 40-köpfiges Team die Spurengaszusammensetzung und spezielle Transportprozesse in der Atmosphäre. Im Rahmen der Messkampagne ESMVal (Earth System Model Validation) wurden  kontinentübergreifende Messreihen erflogen und Beobachtungen vom Boden bis zu 15 Kilometer Höhe in die Troposphäre und untere Stratosphäre durchgeführt. Kampagnenleiter Dr. Hans Schlager vom DLR-Institut für Physik der Atmosphäre berichtet: "Innerhalb von zehn Tagen haben wir in 70 Flugstunden alle Messungen erfolgreich durchgeführt. Wir konnten, wie geplant, verschmutzte Luftmassen von großräumigen Bränden in Afrika, von den Industriegebieten in Südostasien und von europäischen Quellen im Mittelmeer messen".

Mess-Marathon über den Wolken

In der Mittelmeerregion erhoben die Forscher Daten zur Ozonbelastung, in Zentralafrika wurde die Bildung von Stickoxiden untersucht, die durch Blitze in tropischen Gewittern entstehen, im südlichen Afrika wurden die Emissionen von großräumigen Bränden gemessen. In der Stratosphäre der Südpolarregion untersuchten die Wissenschaftler die chemischen Auswirkungen des aktuellen Ozonabbaus, über dem indischen Ozean sondierten sie Reinluftgebiete und schließlich untersuchten sie, wie Luftverschmutzung aus Industriegebieten in Südostasien durch den Monsun in die obere Atmosphäre aufsteigen und bis nach Europa transportiert wird. Die umfangreiche Messkampage erfolgte gemeinsam mit den Universitäten von Frankfurt, Wuppertal, Heidelberg und Mainz sowie dem Forschungszentrum Jülich, dem Karlsruher Institut für Technologie und der Physikalisch-Technischen Bundesanstalt.

Die gewonnenen  Datensätze vergleichen die Forscher nun mit den Berechnungen von globalen Klima-Chemie-Modellen. „Mit diesen umfangreichen Daten können wir  überprüfen, wie gut das Modell des DLR die heutige Zusammensetzung der Atmosphäre wiedergibt. Damit können Prognosen des künftigen Klimas weiter verbessert werden“, betont ESMVal-Projektleitern Dr. Veronika Eyring vom DLR-Institut für Physik der Atmosphäre.

HALO eröffnet neue Möglichkeiten

Damit die lokal gemessenen Atmosphärendaten jedoch auch für die Verbesserung globaler Vorhersagen nutzbar sind, müssen die Messungen großräumig  über weite Strecken, in kurzer Zeit und über einen großen Höhenbereich erfolgen. Die Atmosphäre in den oben genannten Gebieten innerhalb weniger Tage  zu vermessen - das ist nur mit HALO möglich, dem neuen deutschen Forschungsflugzeug. Mit einer Flugdauer von über zehn Stunden, einer Reichweite von über 8.000 Kilometern und einer Flughöhe von bis zu 15,5 Kilometern ist HALO in der Lage, Messflüge in neuen Dimensionen umzusetzen. Mit der Mission ESMVal stellte HALO seine besonderen Fähigkeiten als Messträger für die Atmosphärenforschung mit großem Erfolg unter Beweis. Die Wissenschaftler bringen einmalige und dringend benötigte Datensätze nach Hause - für Erkenntnisse zum Klimaschutz weltweit. Bis 2016 sind mit HALO mehr als zehn weitere wissenschaftliche Missionen geplant.

Über HALO

Das Forschungsflugzeug HALO ist eine Gemeinschaftsinitiative deutscher Umwelt- und Klimaforschungseinrichtungen. Gefördert wird HALO durch Zuwendungen des Bundesministeriums für Bildung und Forschung (BMBF), der Deutschen Forschungsgemeinschaft (DFG), der Helmholtz-Gemeinschaft, der Max-Planck-Gesellschaft (MPG), der Leibniz-Gemeinschaft, des Freistaates Bayern, des Karlsruher Instituts für Technologie (KIT), des Deutschen GeoForschungsZentrums GFZ, des Forschungszentrums Jülich und des Deutschen Zentrums für Luft- und Raumfahrt (DLR).

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Quelle: DLR


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Samstag, 13. Oktober 2012 - 18:26 Uhr

Planet Erde - NASA´s IceBridge Project

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By Christy Hansen, IceBridge Project Manager, NASA Goddard Space Flight Center

If somebody had told me that 2012 would bring with it a deployment to Greenland, Chile, and possibly Antarctica, I never would have believed them. But here I am reflecting back on my three weeks in Kangerlussuaq, Greenland, as I pack for Punta Arenas, Chile. These experiences have been made possible by my new assignment as the project manager of a NASA airborne geophysical project called Operation IceBridge

Christy Hansen in Kanger, Greenland, after one of Operation IceBridge’s science flights. Behind her is the air traffic control tower, as well as the P-3B propellers. Credit: Christy HansenI

started full-time work with OIB this past March. What I truly enjoy about this project is the remarkably talented and extensive team I work with. As the project manager, I must coordinate and help lead a vast team of experts spread out across the country. This team includes polar scientists, instrument engineers, educational/outreach teams, logistics teams, data centers, and aircraft offices. I have to utilize good leadership and communications skills to help my integrated team work together smoothly to achieve a common goal and meet all of our science objectives.

Twice a year, the OIB team travels to Earth’s polar regions to collect data on the changing ice sheets, glaciers, and sea ice. For the Arctic campaign, we use the P-3B 4-engine turbo-prop airplane at NASA Goddard Space Flight Center's Wallops Flight Facility. It has been modified to carry nine different science instruments, including laser altimeters, which measure the different heights of the terrain from aircraft, and various types of radar systems that can actually penetrate the thick ice sheets.

Just four weeks after I started as project manager, I found myself landing in a small Southwestern Greenlandic town called Kangerlussuaq. There was snow on the runway and everyone was bundled in coats. The majority of the buildings looked like military barracks. Most of the OIB team was already there, and they greeted me at the plane. At the time, I knew only one person, the project scientist, and we had only spoken a few times! What an adventure awaited me!

A view of sea ice with open leads of water. Credit: Christy Hansen/NASA

An image of a glacier’s calving front, where it flows and loses ice to the sea. Credit: Christy Hansen/NASA

Each day, we flew at 1500 feet, seemingly scraping the surface of the massive Greenland ice sheet. I felt as though I could have touched it with my fingers if I had just stretched out my hand. It was beautiful.

Watching the team work together like a well-oiled machine, for almost 8 hours at a time, was simply awesome. The pilots, the aircraft maintenance team, and the instrument experts, who collect gigabytes and terabytes of data per flight, collect the invaluable data that tells us what is happening at our poles, and how much the ice is changing each year.

The plane flies over sea ice. The P-3B propeller can be seen out the window of the plane. Credit: Christy Hansen/NASA


My second trip to collect data with the OIB team began last September. For the Antarctic campaign, we use NASA Dryden Flight Research Center’s DC-8 aircraft and operate out of Punta Arenas, Chile. During this Chilean campaign, we will actually fly from Chile, over specific science target regions in Antarctica, and then land back in Chile! That’s an 11-hour round trip flight almost every day!

Christy Hansen hugs the Russell glacier, part of the Greenland Ice Sheet. Credit: Christy Hansen/NASA

Isn’t this exciting? If you want to learn more about what I do and Operation IceBridge’s current Antarctic campaign, join my Google+ Hangout on Wednesday, October 17th from 1-2pm EST. I look forward to talking to you from Chile.

Quelle:NASA


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Samstag, 13. Oktober 2012 - 09:46 Uhr

Mars-Curiosity-Chroniken - Curiosity-News Sol 63-66

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Genauer Blick auf Plastik-Teil von Curiosity:

On Sol 65 (Oct. 11, 2012) of the Mars Science Laboratory mission, NASA's Mars rover Curiosity completed several activities in preparation for collecting its second scoop of soil. Like the first scoop, the next will come from a ripple of sand and dust at "Rocknest," and will be used for cleaning interior surfaces of the sample-handling chambers on the arm.

The Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) tool on the end of arm shook out remnants of the first scoopful and posed for camera inspection to verify it was emptied. The Mars Hand Lens Imager (MAHLI) moved close some loose material on the ground to get a good look. Seeing more detail in the object will help engineers finish assessing whether this loose material from the spacecraft poses any concern for future operations.

Sol 65, in Mars local mean solar time at Gale Crater, will end at 2:22 a.m. Oct. 12, PDT (5:22 a.m., EDT).

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Curiosity's Location During First Scooping

This 360-degree scene shows the surroundings of the location where NASA Mars rover Curiosity arrived on the 59th Martian day, or sol, of the rover's mission on Mars (Oct. 5, 2012). It is a mosaic of images taken by Curiosity's Navigation Camera (Navcam) on sols 59 and 60.

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This image was taken by Rear Hazcam: Left A (RHAZ_LEFT_A) onboard NASA's Mars rover Curiosity on Sol 63 (2012-10-09 17:23:02 UTC) .

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 16:49:52 UTC) .

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 16:50:06 UTC) .

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 16:53:55 UTC) .

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 16:54:14 UTC) .

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 17:01:22 UTC)

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This image was taken by Mastcam: Left (MAST_LEFT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 21:59:00 UTC) .

Image Credit: NASA/JPL-Caltech/Malin Space Science Systems

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This image was taken by Mastcam: Right (MAST_RIGHT) onboard NASA's Mars rover Curiosity on Sol 64 (2012-10-10 22:23:40 UTC) .

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This image was taken by Navcam: Right A (NAV_RIGHT_A) onboard NASA's Mars rover Curiosity on Sol 65 (2012-10-11 21:47:35 UTC) .

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This image was taken by Front Hazcam: Left A (FHAZ_LEFT_A) onboard NASA's Mars rover Curiosity on Sol 65 (2012-10-11 22:27:55 UTC) .

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This image was taken by Mars Hand Lens Imager (MAHLI) onboard NASA's Mars rover Curiosity on Sol 66 (2012-10-12 22:17:20 UTC) .

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This image was taken by Mars Hand Lens Imager (MAHLI) onboard NASA's Mars rover Curiosity on Sol 66 (2012-10-12 22:21:06 UTC) .

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This image was taken by Navcam: Right A (NAV_RIGHT_A) onboard NASA's Mars rover Curiosity on Sol 66 (2012-10-12 22:37:00 UTC) .

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Freitag, 12. Oktober 2012 - 23:55 Uhr

Raumfahrt - Erfolgreicher Start von Sojus-ST-VS03 mit 2 Galileo-Navigation-Satelliten

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Soyuz is given the “go” for tomorrow’s Arianespace launch with a pair of Galileo navigation spacecraft
October 11, 2012 – Soyuz Flight VS03
Arianespace’s third Soyuz launch from the Spaceport in French Guiana has been authorized for liftoff tomorrow on a mission to orbit two additional spacecraft for Europe’s Galileo navigation satellite constellation.
This “go” approval was given today after the regular pre-launch review for Arianespace missions, confirming the readiness of its medium-lift Soyuz, the ELS launch site and associated infrastructure at the Spaceport, along with the network of flight-following tracking stations. 
The mission is designated VS03 in Arianespace’s flight numbering system, and will be performed from the purpose-built ELS launch facility for Soyuz, located in the Spaceport’s northern sector near the city of Sinnamary.
All is set for an October 12 liftoff at 3:15:01 p.m. local time in French Guiana on a mission lasting just under 3 hrs., 45 min., which includes the powered flight of Soyuz’ three stages and two propulsive burns of the Fregat upper stage.
The payload is a second pair of Galileo In-Orbit Validation (IOV) satellites, weighing 700 kg. each, which will join the initial two IOV spacecraft orbited on Arianespace’s historic VS01 flight on October 21, 2011 – which marked Soyuz’ introduction at the Spaceport.
Today’s readiness review followed a full-scale rehearsal, held yesterday, that simulated the launch and involved the same teams and communication links to be used during the actual mission.  Both Galileo IOV spacecraft – which are integrated atop Soyuz in the 4.1-meter-diameter ST payload fairing – have now been activated for their useful operational lifetimes of approximately 12 years.
The four satellites launched on Arianespace’s VS03 and VS01 missions will form an operational mini-constellation that enables a validation of the Galileo system.  All four spacecraft were built by a consortium led by the Astrium division of EADS, with assembly and testing performed by Thales Alenia Space. 
Galileo is a European initiative, with this navigation system being developed in a collaborative effort of the European Union and the European Space Agency.  
Quelle: arianespace
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Update 12.10.2012 / 23.00 MESZ
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Erfolgreicher Start und positive Signale von Galileo-Satelliten!
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Frams; Start-Video ESA
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Quelle: arianespace

3167 Views

Freitag, 12. Oktober 2012 - 10:30 Uhr

Astronomie - AtLast: Die gigantische Teleskop-Entwicklung, um Leben auf anderen Planeten zu finden

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An artist's rendering of ATLAST (courtesy of the Space Telescope Science Institute)
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Twenty years ago, in the year Bill Clinton was elected president, scientists first confirmed the existence of a planet outside our solar system. Now, we know there are thousands of other planets just in our galaxy, even if we've only detected them indirectly. We also finally know what it's going to take to glimpse an exoplanet, to actually see the places that might harbor life like ourselves (or otherwise). And the telescope that will eventually do so is on the drawing board. It has a profound name: ATLAST. 
During the last three years, we have learned that our galaxy is teeming with planets. Since its launch in 2009, NASA's Kepler Mission has discovered more than 2,200 planet candidates orbiting distant stars in the Milky Way. Every year that goes by brings new exoplanet data, and new reasons to think that planets are a commonplace phenomenon in our universe. And yet, pressing questions about these planets remain. We aren't yet sure how many of them are capable of supporting life. The early data from Kepler indicates that as many as one in ten stars has a planet around it that can host liquid water on its surface. If that number holds up, then our galaxy could be home to more than ten billion watery planets, each a potential home for microbes, plants, or even intelligent beings like us. Some may be so close that we could use telescopes to detect signs of life in their atmospheres. The possibility that undiscovered Earths are hiding in every corner of our galaxy is completely reorienting the future of space science. Astronomers sense that they are on the brink of an epochal discovery, and they are keen to build the telescopes that will enable it. 
The Space Telescope Science Institute in Baltimore, Maryland is at the leading edge of this effort. The Institute runs science operations for the Hubble Space Telescope, the most far-seeing instrument ever deployed by humans. The Hubble has had quite a run over its twenty-two years of service, but it is beginning to show its age. In 2009, NASA astronauts serviced the iconic telescope in orbit for the fourth and final time, outfitting it with a new camera and fresh batteries. Still, it's unclear if the Hubble's sensitive instruments can weather another decade of exposure to cosmic rays. Like the Voyager space probes, the Hubble is drifting slowly toward retirement. 
The Institute is currently preparing for the launch of Hubble 2.0 -- the James Webb Space Telescope -- a massive infrared instrument that will be one hundred times more powerful than its predecessor. Unlike the Hubble, the James Webb will be difficult, if not impossible, to service. The delicacy of the Webb's infrared sensors require that it be positioned one million miles from Earth, which is too far for tune-ups. Without the benefit of regular maintenance, it is only expected to last five to ten years.
>Because these machines take so long to build, the Space Telescope Science Institute is already planning for Hubble 3.0. A small working group at the Institute is starting to sketch the conceptual outlines of Webb's successor, a still larger space observatory called the Advanced Technology Large-Aperture Space Telescope (ATLAST). This telescope is being designed with a very special purpose in mind: to discover life on planets that orbit other stars.
Last week, I visited the Space Telescope Science Institute to meet with Matt Mountain, who has served as the Institute's Director for the last seven years. In an extended and wide-ranging conversation, Mountain told me about his vision for the future of astronomy, a vision built around ATLAST and the search for life elsewhere in our galaxy. "The discovery of life on another planet will be as important to the 21st century as Neil Armstrong stepping onto the Moon was to the 20th," Mountain said. "It will be bigger than Copernicus and Darwin rolled into one."
You've been the Director here at the Space Telescope Science Institute for 7 years now. How has astronomy changed in that short time?
Mountain: There are two really important dynamics that are changing the field and the community is still sort of struggling with them. The particle physicists struggled with these issues in the 70's and 80's. 
First, to do cutting edge astrophysics it takes larger, more complex facilities than it once did. It's a matter of simple physics. The power of a telescope, its ability to detect a very faint signal against a noisy background, is directly proportional to the telescope diameter divided by the size of the object you're looking at. It's a very simple ratio. So, if you want to look for planets around other stars or very distant galaxies, those objects are going to be extremely small.
Our detectors today are almost perfect, so it's hard to gain anything by building better detectors. The only way we can get more information about planets around other stars, or distant galaxies, is to make larger telescopes. That's why we have to build these big observatories in Hawaii, and it's why we have to build the James Webb Space Telescope. It isn't because we want to spend billions of dollars, it's because we've been doing space science for four hundred years, and the low-hanging fruits have been picked.
"We've been doing space science for four hundred years, and the low-hanging fruits have been picked."
To answer some of the more profound questions -- Is there life around another star? How did the first galaxies form? -- requires us to look at some very faint things, and we need large, complex facilities to do that. 
That unfortunately moves you away from a traditional academic model of the solitary scientist writing a solitary paper to one where you need a complex machine and a complex organization like this one. And so the other thing you're seeing is a move towards teams; increasingly, it's large teams that are doing the really high impact research and that's because you need a multidisciplinary skill-set to do this stuff. This institution is an expression of that, and in some ways was slightly ahead of its time. We have scientists here, yes, but we also have engineers and software people---we've created a layer of interdisciplinary skills, and that layer allows astronomers to interface with very complicated machines like the Hubble Space Telescope in a very straightforward way. We've hidden the complexity. 
It's a totally different paradigm, and it can be tough for some astronomers to wrap their heads around it, because they're wedded to the ideal of the lone astronomer going up to the mountaintop with his lab book and his worshipful post docs following behind. That's a model that has huge romance and pull, but it's actually not very effective anymore. 
What are some of the most notable successes of the team model?
Mountain: Well take Adam Reiss and his team, who, together with two other teams, won the Nobel Prize last year for discovering dark energy. An individual couldn't have made this discovery. To do what they did, you needed people who understood the theory of supernova explosions, you needed people to figure out how to run these complicated telescopes, both on the ground and in space, and you needed people worrying about data and sophisticated statistics. And this is all very complicated stuff; the person who's an expert in Bayesian statistics and sampling methodologies isn't quite the same person who's an expert in getting the maximum signal from a really faint supernova. But in the end, there's a pay off: Reiss and his team spent most of their Nobel money getting the whole crew to the Nobel ceremony. 
Now let's think about where the team model might take us next. Think about the big question right now: Are we alone? What would it take to answer that question? We've got the Kepler Space Telescope telling us that there are probably planets around every star, so we know that. But now we have another problem: these planets are really, really faint. So faint, in fact, that you need a big telescope to see them, and it has to be quite sophisticated because the planets are next to a very bright star. This is right at the limits of optical technology, which means you need experts in optics and telescopes. So let's say you get a spectrum of the planet's atmosphere, which will allow you to see its chemical makeup. Even then you're still not in the clear, because you've got to understand atmospheric circulation and ecosystems, not to mention how planets form. 
Suddenly you realize that to understand whether there's life around another star, you need a huge, multidisciplinary team. An astronomer might be able to get a spectrum, but they wouldn't know what to do with it, because they weren't built to interpret it. That's why you see someone like Sara Seager -- who is very interested in the question of whether we're alone -- go to M.I.T. where she can do planetary science, but also astrophysics and remote sensing. 
If you want to work at the frontier, with the very best technology possible, you need a huge team. If you want to be a solo theoretician and scribble in your notebook, then maybe you can still make breakthroughs, I don't know. But I do know that these big questions are going to take multidisciplinary teams and that's going to take a culture shift. People in this profession are going to ask themselves some tough questions. Like how do you give tenure to an astronomer who worked in a team of two hundred people? How do you measure their individual contribution? Who do you give the Nobel Prize to? 
The Hubble Space Telescope has now been in operation for over 22 years, during which it has made more than a million astronomical observations. When is it due to be retired?
Mountain: The truth is we don't know. We have a probabilistic assessment of how long the instruments might last. We think the gyroscopes will last until at least 2020. We know the batteries will last at least that long, because the last ones lasted through more than a hundred thousand charge cycles. We know the solar cells work. The real question is how long the instruments will hold up. In principle, we think the instruments will last until at least 2016 or 2018, but it's a crapshoot; it depends upon cosmic rays and how well they built the electronics. 
I want to talk about ATLAST today, but there is one question I want to ask you about the James Webb Space Telescope, the successor to the Hubble, which is due to launch in 2018. When I was first researching the Webb, it really stressed me out to think about how complex its deployment is going to be. In a strange way, the successful landing of Curiosity alleviated a lot of that stress. And maybe these things aren't comparable, but I thought I'd ask you: do you think the Webb deployment will be tougher to pull off than Curiosity's landing?
Mountain: We actually quantified this. We looked at the number of mechanisms in Curiosity's 7 minutes of terror video, and the number of mechanisms involved in deploying the Webb, and unfortunately the number for the Webb was a bit higher. I mean for one it's going to take a lot more time. It's going to take months, and so the experience of it is going to be slow, like water torture. You can't just shut your eyes for seven minutes and open them when you hear the first beep like you did with Curiosity. But Curiosity was encouraging; it showed we could do these very complicated things, and that's good, because if the Webb doesn't work we're screwed. There's no fallback option. 
Tell me about ATLAST, the proposed successor to the James Webb Space Telescope. I know that at this point ATLAST is just a concept, but in some ways I sort of see it as a wish list for the next flagship telescope, and I'm curious what that wish list looks like?
Mountain: Let me give you a completely different way of thinking about it. The question is what is the future of space science? What questions do we want to answer? I'm a pragmatist when it comes to science, and I think the big question that everyone wants answered, and that we can answer, is whether or not we're alone. And we already know what kind of telescope we need to look for life around another star. This is not a difficult problem; it's a Physics 101 problem. We know where all the closest stars are and we know precisely the right distance a habitable planet will be from its star, and we know how bright a planet is. So now assume you can look at a star, but suppress its light, in order to get a spectrum from a planet that's orbiting it. That spectrum will tell us something about that planet's atmosphere; it might even tell us if there's life there. So how big a telescope do I need to do this?
If I assume that every single star has a planet around and that it's in exactly the right place, then I won't need to look at very many to have a good chance of finding life. With a 4-meter telescope, you can look at 10 systems, the 10 closest systems, in this way (the Hubble has a 2.4-meter mirror and the James Webb Space Telescope will have a 6-meter mirror). If I have an 8-meter mirror, I can observe hundreds of star systems in this way, and if I have a 16-meter mirror I can observe thousands. Those may sound like pretty big numbers, but remember in this scenario I'm assuming that there's an Earth in just the right place around every one of these stars. But we're not sure how many stars have a planet in just the right place, and we obviously don't know how many of those planets have an atmosphere with life in it. Kepler is giving us a handle on the first unknown, and it's looking like the answer is 0.1. It's looking like one in ten stars might have a planet in the habitable zone.
"It's looking like one in ten stars might have a planet in the habitable zone."
So now let's say I build my 4-meter telescope. That 1 in 10 chance that only gives me one or two habitable planets to look at, which isn't a very big sample size. Certainly not big enough to tell is whether we're alone or not. And so the question becomes how big do you need your sample size to be? From our perspective, the answer is about a thousand. If there's no life in the closest thousand stars, there's a good probability that we're pretty much alone. 
What sort of leap in the technology do we need to get there? 
Mountain: Well, at first glance, a 16-meter telescope sounds absolutely impossible. But let's think through this. Let's put space aside for a moment and ask ourselves how we got our big ground telescopes. What happened is these astronomers had telescopes with 4-meter mirrors and they realized they weren't big enough to see the faint objects they wanted to look at, objects like distant galaxies. So they tried to build bigger ones, but the problem was that simply scaling up the 4-meter technology didn't work, at least not without spending massive amounts of money. So people like Roger Angel and Jerry Nelson and Ray Wilson came up with brand new technologies; they used active systems and adaptive optics, which eventually earned them the Kavli Prize. These advances allowed them to produce a whole host of new telescopes, facilities like the Gemini Observatory, the Keck Observatory, and the Subaru Telescope.
So I called up my friends at Lockheed Martin and I said "let's figure out what technologies we need to make this work in space" and we both came to the same conclusion. We need the same technologies we've got on the ground: adaptive optics, which make mirrors very lightweight and floppy. We need adaptive optics in space. And I get silence on the other end of the phone. And then they say, "actually, we just bought two adaptive optics companies." And I say to myself, "of course these guys are interested in adaptive optics." Because if you want your spy satellites to have the same resolution as the Hubble, the resolution that allows you see the guy getting out of the car you've been following, then you need 16-meter telescopes out there. That's why you see Lockheed going after technologies like adaptive optics. That tells me that we need to build our partnership with industry.
That's how you get a new 16-meter telescope, a telescope like ATLAST. And that's a very different paradigm from just trying to do it alone. We don't want to become like the particle physicists, who have slowed way, way down, because the technologies they need are technologies that only they need. With these massive accelerators, they have to invent every new technology themselves. Our project of looking for life on other planets uses the same technologies (lightweight mirrors, good detectors, big rockets) that other people want. And to me that project is essential, because the discovery of life on other planets will be as important to the 21st century as Neil Armstrong stepping onto the Moon was to the 20th.
"The discovery of life on other planets will be as important to the 21st century as Neil Armstrong stepping onto the Moon was to the 20th."
More important, I would think.
Mountain: Well, right, but in the framework of people who love the Space Age, the people who wish there was another Kennedy saying "we do this because it's hard, not because it's easy." This would be as radical as Copernicus and Darwin rolled into one. And you'll have kids asking how we can get there. You'd likely see a huge leap in rocket technology. I mean all we've been doing so far is building a better and better steam engine; SpaceX is just the James Watt of the steam engine. We need something beyond steam engines to get out to the stars, and finding life around another planet may be just the thing. It may motivate kids to ask "how do I get to somewhere that's ten parsecs away, because there's a living thing out there and it would be damn cool if we could get to it."
It sounds like the astrobiology is more of a driving force for you than cosmology. Is that right? Is looking for life more important than looking back further and further towards the Big Bang.
Mountain: Well, yes, it is definitely the preeminent goal. But then again, we have Adam Reiss on our staff. I mean it's my view that you have to be able to walk and chew gum at the same time. Cosmology has gotten to a really interesting place, but it's not clear how you make the next breakthroughs in cosmology. That's the problem. Maybe through gravitational waves, that may be the way to go. But, I do know how to look for life around other stars, and I'm a bit like the drunk -- I want to look for my keys underneath the lamppost. Because of Kepler, we know there are other Earthlike planets out there, we know we can get spectra from these places, and we think this is a pretty important question. Not that cosmology isn't full of important questions. But this looking for life is something I can explain and describe in very concrete terms. There's no mystery here. 
So what does the timeline look like for ATLAST? If Webb goes up in 2018, how soon will ATLAST follow?
Mountain: Well we want to put it up before 2032, because if NASA is going to send humans to Mars it will likely do so between 2032 to 2035, when Mars is close to the Earth. It won't be that close again for another twenty-five years. We figure that if NASA decides to do a Mars mission, it's going to be spending most of its money there, because sending humans to Mars will be the most expensive thing we've ever done. There might not be much money left for anything else. So if we're going to get ATLAST up in space, we figure we'd better do it before 2032. But if it were up to me, we'd do it in 2025.
Quelle:The Atlantic

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Donnerstag, 11. Oktober 2012 - 22:16 Uhr

Mars-Curiosity-Chroniken - Curiosity´s erste Stein-Analysen

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The first Martian rock NASA's Curiosity rover has reached out to touch presents a more varied composition than expected from previous missions. The rock also resembles some unusual rocks from Earth's interior.
The rover team used two instruments on Curiosity to study the chemical makeup of the football-size rock called "Jake Matijevic" (matt-EE-oh-vick) The results support some surprising recent measurements and provide an example of why identifying rocks' composition is such a major emphasis of the mission. Rock compositions tell stories about unseen environments and planetary processes.
"This rock is a close match in chemical composition to an unusual but well-known type of igneous rock found in many volcanic provinces on Earth," said Edward Stolper of the California Institute of Technology in Pasadena, who is a Curiosity co-investigator. "With only one Martian rock of this type, it is difficult to know whether the same processes were involved, but it is a reasonable place to start thinking about its origin."
On Earth, rocks with composition like the Jake rock typically come from processes in the planet's mantle beneath the crust, from crystallization of relatively water-rich magma at elevated pressure.
Jake was the first rock analyzed by the rover's arm-mounted Alpha Particle X-Ray Spectrometer (APXS) instrument and about the thirtieth rock examined by the Chemistry and Camera (ChemCam) instrument. Two penny-size spots on Jake were analyzed Sept. 22 by the rover's improved and faster version of earlier APXS devices on all previous Mars rovers, which have examined hundreds of rocks. That information has provided scientists a library of comparisons for what Curiosity sees.
"Jake is kind of an odd Martian rock," said APXS Principal Investigator Ralf Gellert of the University of Guelph in Ontario, Canada. "It's high in elements consistent with the mineral feldspar, and low in magnesium and iron."
ChemCam found unique compositions at each of 14 target points on the rock, hitting different mineral grains within it.
"ChemCam had been seeing compositions suggestive of feldspar since August, and we're getting closer to confirming that now with APXS data, although there are additional tests to be done," said ChemCam Principal Investigator Roger Wiens (WEENS) of Los Alamos National Laboratory in New Mexico.
Examination of Jake included the first comparison on Mars between APXS results and results from checking the same rock with ChemCam, which shoots laser pulses from the top of the rover's mast.
The wealth of information from the two instruments checking chemical elements in the same rock is just a preview. Curiosity also carries analytical laboratories inside the rover to provide other composition information about powder samples from rocks and soil. The mission is progressing toward getting the first soil sample into those analytical instruments during a "sol," or Martian day.
"Yestersol, we used Curiosity's first perfectly scooped sample for cleaning the interior surfaces of our 150-micron sample-processing chambers. It's our version of a Martian carwash," said Chris Roumeliotis (room-eel-ee-OH-tiss), lead turret rover planner at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Before proceeding, the team carefully studied the material for scooping at a sandy patch called "Rocknest," where Curiosity is spending about three weeks.
"That first sample was perfect, just the right particle-size distribution," said JPL's Luther Beegle, Curiosity sampling-system scientist. "We had a lot of steps to be sure it was safe to go through with the scooping and cleaning."
Following the work at Rocknest, the rover team plans to drive Curiosity about 100 yards eastward and select a rock in that area as the first target for using the drill.
During a two-year prime mission, researchers will use Curiosity's 10 instruments to assess whether the study area ever has offered environmental conditions favorable for microbial life. JPL, a division of Caltech, manages the project and built Curiosity. 
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Target: Jake Matijevic Rock
This image shows where NASA's Curiosity rover aimed two different instruments to study a rock known as "Jake Matijevic." The red dots are where the Chemistry and Camera (ChemCam) instrument zapped it with its laser on Sept. 21, 2012, and Sept. 24, 2012, which were the 45th and 48th sol, or Martian day of operations. The circular black and white images were taken by ChemCam to look for the pits produced by the laser. The purple circles indicate where the Alpha Particle X-ray Spectrometer trained its view. 
This image was obtained by Curiosity's Mast Camera on Sept. 22, 2012, or sol 46. 
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High-Resolution View of Cross-Section Through a Mars Ripple
This image shows the wall of a scuffmark NASA's Curiosity made in a windblown ripple of Martian sand with its wheel. The upper half of the image shows a small portion of the side wall of the scuff and a little bit of the floor of the scuff (bottom of this image). The prominent depression with raised rims at the bottom center of the image was formed by one of the treads on Curiosity's front right wheel. 
The largest grains in this image are about 0.04 to 0.08 inches (1 to 2 millimeters) in size. Those large grains were on top of the windblown ripple and fell down to this location when the scuff was made. The bulk of the sand in the ripple is smaller, in the range below 0.002 to 0.008 inches (50 to 200 microns). 
The full scuffmark is 20 inches (50 centimeters) wide, which is the width of Curiosity's wheel. 
This image from the Mars Hand Lens Imager (MAHLI) is the product of merging eight images acquired at eight slightly different focus settings to bring out details on the wall, slopes, and floor of the wheel scuff. The merge was performed onboard the MAHLI instrument to reduce downlinked data volume. 
The image was acquired by MAHLI with the lens about 4.7 inches (12 centimeters) from the target. The pixel scale is about 0.002 inches (50 microns) per pixel. The image covers an area, roughly 3 by 2 inches (8 by 6 centimeters). The image was obtained on Oct. 4, 2012, or sol 58, the 58th Martian day of operations on the surface. 
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Teasing out Mineral Compositions
This graphic made from data obtained by NASA's Curiosity rover shows the ultraviolet portion of the spectrum of data obtained by the Chemistry and Camera (ChemCam) instrument, plus peaks for sodium and potassium, for four observation points on the rock "Jake Matijevic," which intrigued scientists. These were the outlying clusters in the previous figure. Chemcam analyzed a total of 14 points on the rock, zapping each one 30 times with its laser. 
The colors correspond to the colors in the previous figure. Strong emission peaks or regions of peaks corresponding to major elements are highlighted and labeled. Observation point 45-1 is rich in magnesium and somewhat in iron, giving a composition suggestive of the mineral olivine. Point 45-2 is strongly enriched with iron and titanium, suggesting a metal oxide grain, possibly ilmenite. Point 48-10 is rich in silicon, aluminum, sodium and potassium, strongly suggestive of the mineral feldspar. Point 48-14 is high in calcium and has moderate magnesium, consistent with the mineral pyroxene. The top three spectra, or different wavelengths of radiation detected by the instrument, are averages of laser shots six through 30; the bottom spectrum is an average of laser shots 21 to 30. The spectra were obtained at ChemCam distances of 12.8 and 10.5 feet (3.9 and 3.2 meters) from the rock on Sept. 21, 2012, and Sept. 24, 2012 (sols 45 and 48). 
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Likely Pyroxene Mineral Identified in 'Jake'
This plot shows how an observation point in the rock "Jake Matijevic" has a composition consistent with the mineral pyroxene, according to an investigation by the Chemistry and Camera (ChemCam) instrument on NASA's Curiosity rover. The data were obtained on Sept. 24, 2012, the 48th sol, or Martian day, of operations on the surface, when ChemCam zapped the Jake rock with its laser multiple times and analyzed the spectra, or different wavelengths of radiation, emitted from the plasma. This graph plots calcium oxide against magnesium oxide abundance determined from each of laser shots six to 30. 
ChemCam's sixth laser shot is the first dot near near the lower left corner and successive shots move up and to the right. Taking into account the other element abundances along with those of calcium and magnesium allows one to determine that the laser beam was excavating into a material with composition consistent with diopside, a type of pyroxene mineral, at this location in the rock. The laser beam is approximately 0.014 inches (0.35 millimeters) in diameter and removes a layer on the order of 0.00004 inches (one micrometer) with each shot. The line in the plot gives the best linear fit to the data points. 
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What's in Jake?
The graph shows the abundances of elements in the Martian rock "Jake Matijevic" (black line) and a calibration target (red line) as detected by the Alpha Particle X-ray Spectrometer (APXS) instrument on NASA's Curiosity rover. Compared to previously found rocks on Mars, the Jake rock is low in magnesium and iron, high in elements like sodium, aluminum, silicon and potassium, which often are in feldspar minerals. It has very low nickel and zinc. The salt-forming elements sulfur, chlorine and bromine are likely in soil or dust grains visible on the surface of the rock. These results point to an igneous or volcanic origin for this rock. 
The Jake rock was targeted on Sept. 22, 2012, which was the 46th sol, or Martian day, of operations. The calibration target was targeted on Sept. 9, 2012, which was sol 34. APXS obtained its data by aiming alpha particles and X-rays at the rock and observing the energies of the X-rays that are emitted by the sample rock. These data are also known as spectra. The spectra on the rock and calibration target were taken for an hour at night, where the X-ray detector delivers its very best resolution, which means that the elemental peaks are the sharpest. Scales of the two different spectra were adjusted to make comparisons easier because each was measured at a slightly different distance. 
The calibration target was a rock slab brought from Earth with a well-determined composition so that scientists can extract the composition of newly targeted Martian rocks very precisely. 
All other Mars rovers -- Spirit, Opportunity and Sojourner -- were equipped with earlier versions of the APXS, which allows scientists to make detailed comparisons among rocks on different parts of Mars. 
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Different Jake Compositions at Fine Scale
This animated graphic represents compositions indicated by 350 spectra, or analyses of laser plasma light, observed on the rock "Jake Matijevic" by the Chemistry and Camera (ChemCam) instrument on NASA's Curiosity rover. Each spectrum is plotted along three axes in terms of its first three principal components and is color coded by observation point. ChemCam analyzed 14 different points on the rock, taking 30 spectra of each point. The first five spectra at each point were discarded because they were contaminated by surface dust. The remaining 25 spectra from each point cluster together, representing a unique composition for each of the 14 points. The unique compositions indicate that individual mineral grains and combinations of grains are observed, implying that mineral grains are in many cases larger than the 0.014-inch (0.35-millimeter) diameter of the laser beam. In a coarse-grained rock like Jake, the compositions of the outlier points can then be investigated to indicate what minerals are present in the rock. 
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Quelle: NASA

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Donnerstag, 11. Oktober 2012 - 21:47 Uhr

Astronomie - Ein Himmelskörper, der 2011 auf die Erde fiel, dokumentiert die Geschichte des Mars. Erkundet wird sie auch in Wien.

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Am 18. Juli 2011 fiel in der Nacht über Marokko ein gelbgrüner Feuerball vom Himmel, es folgte ein heftiger Überschallknall. Tags darauf schwärmten Beduinen aus bzw. sie wurden ausgeschickt, von Steinhändlern: Der Segen von oben konnte nur ein Meteorit sein, so einer verspricht Geld, und wenn er gar vom Mars stammt, bringt ein Gramm auf dem internationalen Markt tausend Euro. Insgesamt sieben Kilo des zerborstenen Meteoriten fanden sich, sie trugen die Signatur des Mars, ein besonders schönes Stück mit einem Kilo ging nach Wien, ans Naturhistorische Museum, für Direktor Christian Köberl war es „eine Mezzie: 400.000 Euro“.

Das größte Stück ging nach London, von ihm liegen nun erste Analyseergebnisse vor, ein Team um Chennaoui Aoudjehane (Casablanca) hat sie erarbeitet: Demnach wurde der Meteorit vor etwa 700.000 Jahren von einem einschlagenden Himmelskörper aus dem Mars herausgeschlagen, dann war er auf einer Bahn, die die der Erde immer wieder kreuzt, schließlich schlug er ein. Das haben schon viele getan, aber vor langer Zeit, die irdische Verwitterung setzte ihnen dann zu.
Die ganz frischen Bruchstücke dokumentieren hingegen die Verwitterung auf dem Mars. Und die Spuren deuten vor allem auf eines: Wasser. Das hat es irgendwann zur „Lebenszeit“ des Meteoriten gegeben, sein Gestein ist etwa 590 Millionen Jahre alt (Science, 11.10.). Und dieses Wasser hat den Stein nicht nur verwittern lassen, sondern auch Marserde in ihn eingebracht. Natürlich steckt auch die Entstehungsgeschichte des Gesteins im Meteoriten, ihm ist Köberl auf der Spur: „An diesem Meteoriten können wir den Mars viel exakter erforschen, als das mit Rovern vor Ort selbst geht“, erklärt Köberl. „Je feiner die Analysen werden sollen, desto größer müssen die Analysegeräte sein.
Quelle: die presse

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