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Philae May Have Grazed Crater Rim
An anonymous reader writes: The European Space Agency is gradually sorting through the data collected during the brief window Philae was alive and transmitting on the surface of a comet. Analysis of that data has provided another interesting clue about what happened to the probe as it bounced across the comet's surface. According to results from the on-board magnetometer, immediately after the first touchdown, the lander's spin rate increased somewhat. It continued to spin for about 36 minutes until another event dramatically changed its spin rate. This suggests it collided with something, because there was no corresponding vertical deceleration to indicate it had landed once more. Scientists think Philae likely grazed the rim of a crater with one of its landing legs. 65 minutes later, it landed again, and bounced to its final resting place just a few minutes later. The ESA's article has some interesting graphs showing how the data changed as the lander progressed through these different events.
You know, as much as a lot of people are looking at this as a failure, I look at this as a reminder of just how damned difficult this kind of stuff is.
What was it? Ten years in transit, several slingshots around planets to build up speed, deep hibernation for something like two years, waking up, finding where it is in space, find the damned comet, get close to it, and the launch the landing bits and pray that it works because it's all automated.
It really really sucks that this didn't play out as everyone hoped.
But it's mind boggling how many things went utterly right before one thing went wrong.
My mind boggles over the sheer amount of engineering on this which actually worked, and the massive number of things which are lurking to go wrong.
It's hard to even think of an analogy for this ... jumping out of a plane without a parachute and landing in a moving convertible which someone told you 10 years would be passing through the middle of Kansas somewhere around noon ... while blindfolded, knitting a sweater,assembling a piano, and juggling sharks. :-P
And, that might not even come close.
Lost at C:>. Found at C.
Just because you know someone's going to bring it up again for no apparent reason with armchair justification. Thought I'd get it out of the way...
Yes, now that they've read "The Martian" and played some Kerbal Space Program, they're now experts at interplanetary travel.
"I have never let my schooling interfere with my education." - Mark Twain
For those of you making up your own dirty joke: I'm right there with you.
It's beginning to sound more and more like a perfect landing in Kerbal Space Program.
In others news, a record breaking attempt for the longest basketball throw ended with disappointment in a failed rimshot.
For anyone wondering what an RTG is, it is essentially a nuclear battery powered by plutonium with lower weight than solar.
It's not a dumb question for those not familiar with European politics, as the US and Russia use them frequently enough.
The reason they are not used is explained just after the 50 minute mark in the interview below. Basically, for political as well as safety and security reasons, the ESA has their hands tied and will neither develop nor use RTG technology. Indeed, a small part of the ROSETTA mission was to showcase that they didn't need the technology to conduct long-distance missions.
https://www.youtube.com/watch?v=7Xm6y0LzlLo#t=3072
IMHO, this mission is not only successful, but VERY successful. Data gathered during this mission is extremely informative. This mission was a bet against lack of information, systems degradation in space, aging of both materials and staff, political turbulences, and a loooong list of other barriers that were surpassed.
This mission is inspiring. I hope everyone remembers this historical milestone.
to be fair, the no RTG thing is political.
Actually, the ESA is developing RTGs based on americium-241 rather than plutonium.
http://www.lpi.usra.edu/meetings/nets2012/pdf/3043.pdf
In some cases it's political. In this case it was weight.
This space intentionally left blank
cost to lift is political :)
We went as cheap as possible, and I'd heard ESA won't use radioactives anyway.
So, in a word, we have actually rimmed a comet?
That excludes more than you know. Many elements are slightly radioactive.
For example, lead is approximately 1,4% lead-204. If you really want to work without radioactive isotopes you gotta spin up the centrifuges.
And you gotta have deep pockets.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.