Engineers have successfully tested a spare reaction wheel on Mars Odyssey in their effort to bring the spacecraft back into full operation.

Engineers have successfully tested a spare reaction wheel on Mars Odyssey in their effort to bring the spacecraft back into full operation.

After more than 11 years of non-operational storage, the spare reaction wheel passed preliminary tests on Wednesday, June 12, spinning at up to 5,000 rotations per minute forward and backward. Odyssey engineers plan to substitute it for a reaction wheel they have assessed as no longer reliable. That wheel stuck for a few minutes last week, causing Odyssey to put itself into safe mode on June 8, Universal Time (June 7, Pacific Time).

Mars Odyssey put itself into safe mode on Friday when it detected problems with one of the three reaction wheels used to orient the spacecraft.

Mars Odyssey put itself into safe mode on Friday when it detected problems with one of the three reaction wheels used to orient the spacecraft.

If this space probe goes down, it will make it more difficult to rely data back from Opportunity, now on the Martian surface, and Curiosity, due to land in two months.

Mars: dry with only periodic short bursts of wetness.

Mars: dry with only periodic short bursts of wetness.

Though this Science article outlines well the present “consensus” for Mars’s past climate, it also tries to make it sound like the planetary science community had once believed that Mars was once ocean-covered like the Earth and now has abandoned that consensus. To this I say bunk. Though many respected planetary scientists have looked for and found evidence for a past ocean on Mars, this possibility has always been controversial. From my readings most planetary scientists have always believed that Mars has generally been dry, interspersed with short periods when there is flowing liquid water on its surface. Even the advocates of the Martian ocean never proposed an Earthlike ocean, but a somewhat shallow and short-lived phenomenon.

Scientists have found more evidence that the streaks on Martian hillsides that darken in warm weather are caused by melting groundwater flowing downhill.

Liquid water on Mars! Scientists have found more evidence that the streaks on Martian hillsides that darken in warm weather are caused by melting groundwater flowing downhill.

Last summer, the team pointing the HiRISE camera on the NASA Mars Reconnaissance Orbiter (MRO) dropped that bombshell: it had identified 7 confirmed and 12 likely sites that contained hundreds of narrow streaks on steep slopes inside crater walls. During warmer seasons, as temperatures rose as high as 27 degrees Celsius, the streaks darkened, and then faded again. Salts could allow brines to be liquid at these temperatures. Today at the Lunar and Planetary Science Conference in The Woodlands, Texas, the HiRISE team announced that it now has doubled it stash of streaks, with the identification of 15 confirmed and 23 likely sites, all in the mid-latitudes of the Southern Hemisphere.

Additional analysis of the spectrographic data also suggests that water could be the cause of the darkening.

When a solar storm slammed into both the Earth and Mars in January 2008, scientists were able to directly measure the importance of the Earth’s magnetic field in protecting our atmosphere from oxygen loss.

When a solar storm slammed into both the Earth and Mars in January 2008, scientists were able to directly measure the importance of the Earth’s magnetic field in protecting our atmosphere from oxygen loss.

They found that while the pressure of the solar wind increased at each planet by similar amounts, the increase in the rate of loss of martian oxygen was ten times that of Earth’s increase. Such a difference would have a dramatic impact over billions of years, leading to large losses of the martian atmosphere, perhaps explaining or at least contributing to its current tenuous state. The result proves the efficacy of Earth’s magnetic field in deflecting the solar wind and protecting our atmosphere.

All NASA funding for the European ExoMars mission appears to have been cut by the Obama administration.

All NASA funding for ESA’s unmanned ExoMars mission appears to have been cut by the Obama administration.

A public announcement by Nasa of its withdrawal from the ExoMars programme, as it is known in Europe, will probably come once President Obama’s 2013 Federal Budget Request is submitted. This request, expected in the coming days, will give the US space agency a much clearer view of how much money it has to implement its various projects. “The Americans have indicated that the possibility of them participating is now low – very low. It’s highly unlikely,” said Alvaro Gimenez, Esa’s director of science.

Though this story doesn’t confirm the earlier rumors that the Obama administration was going to eliminate the entire NASA planetary program, it sure lends those rumors further weight. However, the new budget should be released any day now, when we will finally find out.

Mars Express has found more evidence that Mars once had oceans.

Mars Express has found more evidence that Mars once had oceans.

Two oceans have been proposed: 4 billion years ago, when warmer conditions prevailed, and also 3 billion years ago when subsurface ice melted following a large impact, creating outflow channels that drained the water into areas of low elevation.

“MARSIS penetrates deep into the ground, revealing the first 60–80 metres of the planet’s subsurface,” says Wlodek Kofman, leader of the radar team at IPAG. “Throughout all of this depth, we see the evidence for sedimentary material and ice.” The sediments revealed by MARSIS are areas of low radar reflectivity. Such sediments are typically low-density granular materials that have been eroded away by water and carried to their final destination.

This later ocean would however have been temporary. Within a million years or less, Dr Mouginot estimates, the water would have either frozen back in place and been preserved underground again, or turned into vapour and lifted gradually into the atmosphere. “I don’t think it could have stayed as an ocean long enough for life to form.”

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