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Double asteroid belt in Solar System clone

...Spitzer observations have discerned two rocky asteroid belts and an icy outer ring surrounding our Sun’s doppelgänger Epsilon Eridani that could have been shaped by evolving planets..

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Fireball captured by Canadian cameras

...for the second time this year The University of Western Ontario’s Meteor Group has captured rare footage of a meteor streaking across the sky and possibly falling to the ground...

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ESA gravity mission slips to 2009

...the launch of Europe’s Gravity field and steady-state Ocean Circulation Explorer (GOCE) has slipped to February 2009 due to ongoing technical faults with its launcher..

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Video archive

STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.


STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.


STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

 Full presentation
 Mission film

STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.


Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

 Full coverage

Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

 Launch | Science

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More video

Phoenix in "precarious times" following power fault

Posted: October 30, 2008

NASA’s Phoenix Mars Lander tripped into safe mode yesterday in response to a low-power fault, and unexpectedly switched on to the ‘B-Side’ of its redundant electronics, shutting down one of its two batteries in the process.

During safe mode, the lander stops non-critical activities and awaits further instructions from the mission team. Engineers were able to kick start battery charging by sending commands from Earth to the failing lander, but the harsh weather conditions are taking their toll.

NASA's Mars Phoenix Lander is slowly shutting down as winter sets in. The mission, already in its fifth month of a 90 day mission, suffered a fault yesterday due to the
deteriorating weather conditions. Image: NASA/JPL-Calech/University of Arizona.

"This is a precarious time for Phoenix," says Phoenix Project Manager Barry Goldstein. "We're in the bonus round of the extended mission, and we're aware that the end could come at any time.  The engineering team is doing all it can to keep the spacecraft alive and collecting science, but at this point survivability depends on some factors out of our control, such as the weather and temperatures on Mars."

Phoenix has recorded the lowest temperatures yet, dipping to -96 degrees Celsius at night and barely rising above -45 degrees Celsius in the day. Dust-storms and water-ice clouds add additional challenges, reducing the amount of sunlight reaching Phoenix’s solar panels, thereby restricting the amount of power the lander can generate. On Tuesday, low temperatures triggered Phoenix’s emergency battery heaters into action, creating another drain on precious power supplies.

"It could be a matter of days, or weeks, before the daily power generated by Phoenix is less than needed to operate the spacecraft," says JPL mission manager Chris Lewicki. "We have only a few options left to reduce the energy usage."

Only this week did mission leaders announce plans to turn off four heaters, one at a time, in an effort to preserve power. The faults experienced yesterday forced the engineers to shut down two heaters instead of one as originally planned, ceasing operations of the robotic arm, robotic arm camera and the thermal and evolved-gas analyser. The second heater served the lander's pyrotechnic initiation unit, which hasn't been used since landing.

Science activities will remain on hold for the rest of the week to allow the spacecraft to recharge and conserve power. It is still hoped that Phoenix will be able to perform meteorological observations at the very least, for some weeks to come.


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Oct 29 Falling power forces heater shutdown read more

Oct 22 Phoenix completes soil delivery read more

Oct 08 Phoenix digs into darkness read more

Sep 30 Phoenix sees falling snow read more

Sep 29 Phoenix peeks under a rock read more

Sep 12 Dust devils pay visit to Phoenix read more

Sep 05 Phoenix's vapour quandary read more

Aug 26 Phoenix digs into extended mission... read more

Aug 06 Martian salts analysed for habitability... read more

Aug 01 Phoenix tastes water on Mars read more

Jul   29 Sticky situation for Phoenix read more

Jul   22 Phoenix in 24-hour monitoring assignment read more

Jul   17 Phoenix rasps frozen layer... read more

Jul   11 First success with Phoenix soil probe... read more

Jul   10 Phoenix struggling with icy payload read more

Jul   03 Next Phoenix bake could be last read more

Jun  30 Phoenix soil could support life read more

Jun  23 Frozen water confirmed on Mars read more

Jun  19 Bright chunks must have been ice read more

Jun  17 First results from Phoenix bakery read more

Jun  12 An oven full of sand read more

Jun  10 Clumpy Martian soil challenges Phoenix read more

Jun  06 Closest view ever of Mars sand read more

Jun  03 Phoenix scoops up Martian soil read more

Jun  02 Phoenix sees possible ice read more

May 30 Phoenix flexes robotic arm read more

May 28 HiRISE captures Phoenix descent read more

May 26 Spectacular new colour view of Mars read more

May 23 Phoenix prepares for Mars landing read more