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Hibernating magnetar springs to life

...a mysterious celestial object that emitted 40 visible light flashes before disappearing again could be a missing link in the family of neutron stars...

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Evidence of life could survive in Martian meteorites artificial meteorite plunged through the Earth’s atmosphere has shown that traces of life could survive the high temperatures and pressures endured in such an ordeal...

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Solar wind at 50 year low

...the Sun’s solar wind output is at its lowest levels since recordings began, an effect that could see our natural shielding to cosmic rays diminish...

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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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Phoenix peeks under a rock

Posted: September 26, 2008

Earlier this week Phoenix used its robotic arm to slide a rock away from an area of soil that could shed light on the processes that effect the presence of ice on Mars.

Phoenix had enlarged the trench near the videotape-sized rock –- nicknamed “Headless” – two days earlier in preparation for the ground moving maneuver to slip the rock into the trench. The ground surface between the rock's prior position and the lip of the trench had a slope of about three degrees downward toward the trench.

"The rock ended up exactly where we intended it to," says Matt Robinson of NASA's Jet Propulsion Laboratory.

Phoenix slipped the "Headless" rock (originally located just above the trench in the top image) into a trench earlier this week (bottom image), in order to study the soil underneath the original location of the videotape-sized rock. Image: NASA/JPL-Caltech/University of Arizona/Texas A&M University.

Although the robotic arm was not designed to heave rocks around the Phoenix workspace, the motivation was in the layer of hard, icy material discovered around the landing site. Excavating down to that hard layer underneath a rock might provide clues about processes affecting the ice.

"The appeal of studying what's underneath is so strong we have to give this a try," says Michael Mellon, a Phoenix science team member at the University of Colorado. "The rocks are darker than the material around them, and they hold heat. In theory, the ice table should deflect downward under each rock. If we checked and saw this deflection, that would be evidence the ice is probably in equilibrium with the water vapour in the atmosphere."

The scientists also speculate that if the icy layer were found closer to the surface under a rock, it could be that the rock is collecting moisture from the atmosphere, with the moisture becoming part of the icy layer.

Whatever new findings are derived from the study of the soil underneath the rock, scientists will be given a fresh insight into the ways in which the Martian atmosphere and surface are intimately linked.

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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