May 9th, 2008 by Mox
When the space shuttle Columbia broke up during reentry on February 1, 2003, one of the experiments it was carrying was called CVX-2 (Critical Viscosity of Xenon). It was designed to study the way xenon gas flows in microgravity. The experiment ran for 370 hours and the CVX team was able to download about 85% of the data while the Columbia was in orbit, confirming that it was working as expected. The complete dataset was stored on a 400MB hard drive that was part of the test apparatus carried on the shuttle.
It was initially thought that the hard drive did not survive the reentry, but when it was discovered to be largely intact albeit severely damaged, the project team sent it to a data recovery service. The contents of the drive came back about 99% complete, but it still took several years to analyze the data. The results were published just last month and confirmed that xenon experiences a sudden change in viscosity known as shear thinning when it is stirred vigorously. This effect is what allows whipped cream and ketchup to from flowing smoothly like a liquid to holding their shape like a solid.
While this wasn’t necessarily an earth-shattering experiment, it was fortunate that it could be completed as the lead investigator, Robert Berg, expressed in this Scientific American article:
He notes that the experiment could have only worked in microgravity, to prevent the xenon from settling under its feather-light weight. With NASA’s priorities shifting away from basic research, he says, “this is the sort of experiment that won’t be duplicated for a long time, if ever.”
Computer World has a more technical explanation of the data recovery process.
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February 5th, 2006 by Mox
Friday, the astronauts aboard the International Space Station “launched” a satellite made from an old spacesuit outfitted with sensors and a radio transmitter. This “SuitSat” was to be a proof-of-concept for recycling used spacesuits into useful satellites. Transmitting on a frequency of 145.990 MHz, SuitSat was to broadcast a pre-recorded greeting followed by telemetry information to anyone listening on a ham radio or police scanner over the course of a couple of days. Unfortunately, transmissions have reportedly been very faint and, for a little while, it was even thought to have failed completely.
I was hoping to get a chance to listen to it myself, but so far I have only picked up static. Hopefully some useful information can be gleaned from this experiments and there will be more like it in the future.
More articles:
AMSAT - 1, 2
CNN
MSNBC
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January 26th, 2006 by Mox
This month marks the two years of service for the Mars Exploration Rovers. Their original 90-day missions have been extended three times and, for the most part, they’re still going strong.
While showing signs of wear, Spirit and Opportunity are still being used to their maximum remaining capabilities. On Spirit, the teeth of the rover’s rock abrasion tool are too worn to grind the surface off any more rocks, but its wire-bristle brush can still remove loose coatings. The tool was designed to uncover three rocks, but it exposed interiors of 15 rocks.
On Opportunity, the steering motor for the front right wheel stopped working eight months ago. A motor at the shoulder joint of the rover’s robotic arm shows symptoms of a broken wire in the motor winding. Opportunity can still maneuver with its three other steerable wheels. Its shoulder motor still works when given extra current, and the arm is still useable without that motor.
Their current mission extension lasts through September 2006.
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