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Comet Probe Philae To Deploy Drill As Battery Life Wanes
An anonymous reader writes With less than a day of battery life left, The European Space Agency's Philae probe will begin to drill for samples even though the drilling may dislodge it. From the article: "Philae is sitting in the shadow of a cliff, and will not get enough sunlight to work beyond Saturday. Friday night's radio contact with the orbiting Rosetta satellite will be the last that engineers have a reasonable confidence will work. The team is still not sure where on the surface the probe came to rest after bouncing upon landing on Wednesday. Scientists have been examining radio transmissions between the orbiter and the lander to see if they can triangulate a position. This work has now produced a 'circle of uncertainty' within which Philae almost certainly lies."
Part of the problem is that some of the systems intended to help the probe land properly aren't working, like the thruster on top.
Some of it seems like just poor planning though. How hard would it have been to install a bright LED on the top that Rosetta could see from a few km away? LEDs don't weigh much and you only have to run it while Rosetta is taking the picture so the power budget would be nominal. It seems better than not being able to find the lander because it is in shadow.
I read the internet for the articles.
Lander had to be as light as possible to make it out there with their expected launch volumes. The lander only weighs ~20kg.
Another stunning image of my new home taken by ROLIS during #CometLanding yesterday, when I was just 40 m from #67P pic.twitter.com/I8OZ5kXjXA
Philae bounced twice, the first bounce was about two hours, the second one 7 minutes. If the gravity on the comet is 1/200,000th that on earth (a reasonable estimate, it varies around the comet because it's *way* not round) then the first bounce was about 1,000 feet off the surface, but the second one was only about three feet. Seven minutes to fly up and down three feet; that's almost impossible to imagine.
I love Mondays. On a Monday, anything is possible.
That's why they gave it batteries that last long enough to fulfill the primary objectives of the lander.
The solar panels were for the icing on the cake. Or rather the icing on the icing of the cake - most of the scientific relevant data is collected by the orbiter.
GP is right - there's no other place where the gap between actual and imagined capabilities is so dramatic as on Slashdot. I really wonder where this overestimation of the own capabilities coupled with an uncalled-for arrogance comes from.
That's a strange assumption. Whence did it come?
I did intend to say maybe 10-100 billion, but went with the higher end because of how expensive it is to get people just considering how expensive it is to get people to near-earth orbit and inflation adjusted prices for the Apollo program. It could easily cost a lot more than that, but even if you take the lower bound of $10 billion, that still can buy a lot robots for ten times the price, especially since a large fraction of the cost is development costs. With few exceptions, space agencies seem to focus on using money to develop new and better probes instead of producing a few of the same type, even though that is an option.
Probably yes.
And from someone complaining about assumptions. It really comes down to what science goals you are trying to achieve. If your goal is to move manned flight ahead, then of course you need to do things with more people, although don't need to disguise it as being done to improve success rate of missions like this. If your purpose is to do composition analysis of materials, and measure mass distribution in comets and asteroids, especially in some sort of comparative sense, then a boring probe would be great at doing repetitive scans.
At this price and success rate, hardly.
Seriously, are you dense enough to think that a sample size of one is a great estimate of success rate? Which is also not perfect for manned missions either? And also think that we could send a person for the same cost as a single unmanned mission, and couldn't send multiple unmanned missions for the price of a single manned mission?
I wasn't specifically asking for you to go, there are quite a few people who have more skills than being able to duct tape.
I only design and build high resolution spectrometers for a living, including ones that get used in laser induced breakdown spectroscopy. The issue is not that I only know how to use duct tape, but that I know exactly how much equipment and tooling is needed to build such instruments, considering I've built them from scratch in a machine shop myself. Once constructed, a lot of instruments will have very limited flexibility to be changed with portable tools. They won't have a full machine shop there, and even then a lot of specialized components can't be made in a normal machine shop and require a lot of other special tools and services. A person could still tweek something in situ. But considering even a robot mission like this has over a dozen different instruments, it isn't just about knowledge of how to service all of them, but also time. It is bad enough screwing around with alignment on an optical device for a whole day because of a spec change or design fault when you have a nice open lab and that is the only instrument you are working on at the moment. At some level, regardless of the skills of the person, they're options will be limited to banging on something a few times before moving on to something else with less risk of eating up too much time.
But as you said, I guess I don't have enough skills to have an opinion on such things, and am sure that you aren't making any assumptions or superficial judgements despite the lack of content in your post.