Venus Express mission ends

After eight years, the European Space Agency has officially ended the Venus Express mission.

After this month of ‘surfing’ in and out of the atmosphere at low altitudes, the lowest point of the orbit was raised again through a series of 15 small thruster burns, such that by 26 July it was back up to about 460 km, yielding an orbital period of just over 22 hours. The mission then continued in a reduced science phase, as the closest approach of the spacecraft to Venus steadily decreased again naturally under gravity.

Under the assumption that there was some propellant still remaining, a decision was taken to correct this natural decay with a new series of raising manoeuvres during 23–30 November, in an attempt to prolong the mission into 2015. However, full contact with Venus Express was lost on 28 November. Since then the telemetry and telecommand links had been partially re-established, but they were very unstable and only limited information could be retrieved.

The agency has decided that further attempts to contact the spacecraft would essentially be a wasted effort, and has closed the books on this very successful mission. The spacecraft itself will soon burn up in Venus’s atmosphere when its orbit decays.

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Boeing to bid CST-100 for ISS cargo contract

The competition heats up: Boeing has submitted a bid for the next round of ISS cargo missions, proposing to use its CST-100 manned craft as an unmanned freighter.

The cargo version of Boeing’s CST-100 spacecraft will be based on the crewed version the company is developing for NASA, said John Mulholland, Boeing commercial crew program manager. Boeing will remove spacecraft components not needed for crew missions, like its launch abort system and environmental controls, to free up room in the spacecraft for cargo. The cargo version of CST-100 would, like the crewed version, launch on a United Launch Alliance Atlas 5 rocket. The cargo version will also be able to return cargo to Earth, landing in the western U.S. like the crewed version.

This makes sense to me.

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Curiosity finds organic materials on Mars, including fluctuating levels of methane

Data from Curiosity has found both organic chemicals in the surface of Mars as well as quickly changing levels of methane in the nearby atmosphere.

NASA’s Mars Curiosity rover has measured a tenfold spike in methane, an organic chemical, in the atmosphere around it and detected other organic molecules in a rock-powder sample collected by the robotic laboratory’s drill. “This temporary increase in methane — sharply up and then back down — tells us there must be some relatively localized source,” said Sushil Atreya of the University of Michigan, Ann Arbor, and Curiosity rover science team. “There are many possible sources, biological or non-biological, such as interaction of water and rock.”

The organic material does not prove there is or was ever life on Mars. What it shows is that conditions on Mars could have once supported life. The methane detection, however, is a more significant finding, as it suggests that something very nearby to Curiosity is causing the spike. It could be life, or it could be chemical activity, but in either case, it means there is activity.

The one caveat is that the spike still did not amount to much, 7 parts per billion. Whatever is causing it is not really doing very much.

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Evaporating dry ice chunks create gouges on Mars

Scientists think they have solved the mystery of the gouges that appear seasonally on some hillsides on Mars: Chunks of dry ice that slide down the slope and then evaporate, leaving no trace.

During the martian winter, carbon dioxide ice freezes over parts of the planet’s surface and sublimates back into a gas during the spring thaw. But according to the model presented here today at a meeting of the American Geophysical Union, chunks of warming dry ice may also break off from the crests of dunes and skid down slopes. This is no ordinary tumble—according to the model, the bases of the chunks are continually sublimating, resulting in a hovercraftlike motion that gouges the dune while propelling the ice down slopes. Solid ice that survives to the bottom settles into a pit before dissipating back into the atmosphere.

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NASA builds a $349 million test stand it knows it will never need

SLS marches on! Though Obama cancelled the Constellation rocket program in 2010, NASA continued to build a $349 million engine test stand for that rocket, finishing the tower in June 2014.

The test stand was also significantly over budget. It now sits useless, since the SLS rocket will use a different untested engine in its upper stage during its first manned flight.

It is every important to underline the chronology here. The rocket was cancelled in 2010. Construction on the test stand continued however for four more years, partly because of decisions by NASA management and partly because of mandates forced on them by Congress.

Stories like this illustrate why I think the political clout of SLS is weak. The program is too expensive, is riddled with waste, and it can’t accomplish anything anyway, making it a perfect target for both muckraking journalists and elected officials who want to make a name for themselves saving the taxpayer’s money. And both have a perfect inexpensive and successful alternative to turn to: private space.

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Simon & Garfunkel – American Tune

An evening pause: Performed live in New York, 1981.

I’ve posted a different Paul Simon performance of this song previously, but considering what SpaceX is about to try to do with its first stage, I think it appropriate to post it again. As Simon wrote,

We came on a ship they called the Mayflower
We came on a ship that sailed the moon
We came in the age’s most uncertain hour
And sing an American tune.

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