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Fascinating Rosetta Image Captures Philae's Comet Bounce
mpicpp points out that high-resolution pictures have been released of Philae's landing. "The hunt for Rosetta's lost lander Philae is gaining steam as scientists pore over images from above the comet that may help reveal its final location. The ESA released an image Monday taken by Rosetta's OSIRIS camera showing Philae's first bounce on the comet. The mosaic includes a series of pictures tracking the lander descending toward the comet, the initial touchdown point and then an image of the lander moving east. 'The imaging team is confident that combining the CONSERT ranging data with OSIRIS and navcam images from the orbiter and images from near the surface and on it from Philae's ROLIS and CIVA cameras will soon reveal the lander's whereabouts,' says the ESA."
Never put 20 inch rims on your lander.
I haven't really been following this too closely so this may be entirely impossible, but if Philae is located, could Rosetta be positioned to reflect enough sunlight onto Philae to help power it?
Hey, they've done something that nobody has done before. Kudos are in order. Low-gravity landings on giant loose lint-balls are still new territory.
The amount of science returned is still unknown because they are still sifting the data. At the very least, they got close-up photos of the surface of a comet for geologists to study.
I hope they take their lessons and make a better comet mission.
Remember, the US Ranger program took 7 tries before they had success. The comet mission had partial success on the first try! Practice makes perfect.
Perhaps they can make the next one spherical and not require any particular landing orientation. Put wire-frame bumpers on it and let it go ahead and bounce. It can adjust its angle after a landing.
Table-ized A.I.
Well, yeah. The comet rotates. The direction of its rotation is east. It's as good a coordinate system as any.
East. Now in space.
It has always been in space, it is the rotational direction where the sun rises.
The purpose of the mission wasn't just to land something on the surface and have it continuously live stream.
They still have the orbiter with a big instrument suite, which will continue to provide useful data.
The lander had two goals. One was to operate all the instruments and collect data at least once. The non-rechargable 1200Wh Li/SOCl2 batteries allowed this to happen, exactly as planned, even without the sun. It didn't land where planned, but it did land, collect the data, and transmit it.
The second part was a longer term monitoring, which the solar cells recharge the smaller 150Wh Li-Ion batteries to support. This is the part that's in jeopardy.
Remember Voyager 1, the probe sent out in 1977 that's 18 light hours away? The Plasma Spectrometer and Photopolarimeter System sensors were defective. Four others sensors had to be disabled because it's running out of power. What a colossal boondoggle.
Put something in orbit. CHECK
Land on a comet. CHECK
Perform sciency stuff: CHECK
The landing wasn't perfect. All the sciency stuff was complete at a little over 80% accomplished.
Measure this in scientific progress, not scientific perfection. If you are looking for perfection on the first attempt of anything, get out of science.
A summary, for those who were fortunate enough to miss this:
/. pretending that a handful of articles about a shitty T-shirt and a subsequent "forced" apology show that lolfeminists, even those with PhDs in relevant, don't care about this mission.
1. Dude wears a shirt with scantily-clad women. Some people say it's kinda sexist.
2. Dude sincerely apologizes. Those who complained accept.
3. Everyone moves on. Lessons learned. Yay! Pretty comet pictures!
4. LOL just kidding. A bunch of "supporters" who won't STFU see this is a great opportunity to attack straw feminists and comment on every single article mentioning the mission. Those who objected to his shirt, typically women scientists/engineers, are slandered as "taking away from his accomplishments" despite writing about this mission for, in some cases, years. Assholes start an Indiegogo campaign to buy him, specifically, a watch for being "bullied," which is forcing him to deal with a situation he's clearly ready to move on from. MRA and GamerGate types congregate, attacking and doxxing anyone who had the slightest of problems with his shirt.
So of course we have folks on
"The science data they set out to collect was still obtained." Do we really know yet if the probes and drills actually reached down below the surface? It appeared that lander was sticking up and I have my doubts. I think it would be wonderful if they actually got the samples they hoped they would get, but I am not convinced. There is an article behind a pay wall in the WSJ that says an instrument discovered an organic compound that was first detected in the comet’s atmosphere. Says the molecule was detected by an instrument on the lander "sniffing" the comet's atmosphere. Seems there is no more information than that. Hard to say if we can take that to mean they actually got their samples. Sniffing the comet's atmosphere != soil samples.
Really?
Hard to know where to start. Firstly the whole landing was just a small part of the mission. The orbiter is still up there and, all being well, will follow the comet in to
perihelion, observing all the way.
Secondly, think about the trade-offs of planning a space probe. You can make things more robust and more redundant, design more conservatively, etc. reducing the risk of things failing, but that costs you mass and power (and possibly money) which are rigidly limited. So you would have to take fewer instruments. The design optimises the expected science return by taking some risks.
The lander was intrinsically high risk, because no one had any idea what the surface of a comet is like. They had to gave it a bunch of different ways of hanging on designed around some plausible guesses. The lander has no propulsion at all (those mass trade-offs again), so it has to put up with wherever it hits. They knew solar power on the surface was uncertain, so they had enough juice in the non-rechargable battery to do the highest priority science.
In the event, two systems failed -- the cold gas hold down thruster and the harpoons. No one knows why yet, but building systems on a very tight mass budget that can work after 10 years in space is not easy. In addition, the surface of the comet seems to be harder than anyone really expected.
Given the challenges, getting any science at all back from the lander is amazing and a bonus to the main mission which is the orbiter.
I don't see how that follows from the quoted text.
Regarding the harpoon, many "successful" US missions also had problem spots. For example, Galileo's main antenna didn't open, greatly limiting imaging data, but still did lots of other measurements. And its atmosphere probe had a key part on backward, but got lucky and still managed to work. Voyager's antenna boom kept shifting around, missing some key shots. Pioneer 10 and 11 got confused by Jupiter's radiation and missed a couple of moon photos. Viking 2's seismometer didn't work. Apollo 11's guidance computer got swamped with processing jobs and stopped working. Spirit's memory got full, stopping all work for a couple of weeks.
There is no AAA out there: you improvise and cross your fingers.
Table-ized A.I.