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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."
Drill baby, drill!
We'll be hosting an #esahangout on #cometlanding from ESOC today at 13:00 GMT/14:00 CET, details shortly plus.google.com
Why was this designed to use mainly solar instead of a radioisotope thermoelectric generator like the voyager probes?
A comet's trajectory out of the solar system would have been interesting thing to ride on, but then solar wouldn't be a viable option.
What state would the man be in after 10 years in space?
How big would the initial launch have had to be to keep a man alive for 10 years in space?
Watch this Heartland Institute video
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.
Because Philae does't have any manouvering capability (appart from some springs).
And even if it had, with a 2x28 minute round trip time who would give the orders?
Watch this Heartland Institute video
"It seems to me the design and/or planning of this mission were poorly thought out"
Is the funniest fucking thing I've heard all day. Do you have any idea how well thought out this mission was? FFS look at the trajectory it took 10 YEARS(!) to get to the comet. And you think they overlooked the fact that the comet is craggly?
Jesus-Dunning-Kruger-Christ.
http://www.esa.int/esatv/Video...
Because nukes are environmental hazardous. Remember, this thing was designed in Europe.
My penetrator always hammers the MUPUS. Wait, what?
but it's running out of power...shit.
Is the shadow a permanent problem? Or will it potentially get back into the sunlight at some point as the comet reaches a different part of its orbit?
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
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
> What state would the man be in after 10 years in space?
The "Bored" state.
---- MISSING MISCELLANEOUS DATA SEGMENT --- [sigdash] trolololol
Radioisotope thermoelectric generators (RTGs) are big, heavy, and emit radiation that screws up some of the instruments.
The ones on Voyager are about the size of Philae. from Wikipedia: The GPHS-RTG has an overall diameter of 0.422 m and a length of 1.14 m.[1] Each GPHS-RTG has a mass of about 57 kg and generates about 300 Watts of electrical power.
Philae:
Launch mass 100 kg (220 lb)[1]
Payload mass 21 kg (46 lb)[1]
Dimensions 1 Ãf-- 1 Ãf-- 0.8 m (3.3 Ãf-- 3.3 Ãf-- 2.6 ft)[1]
Power 32 watts at 3 AU[2]
Unfortunately, RTGs don't come in multiple sizes, so you can't get a 1/10th scale RTG that weighs 6kg and is 15 liters in volume.
I don't know if ESA has access to RTGs in the first place, or if public policy would allow launching with a radiation source. The Cassini RTGs causes a huge public relations problem when it was launched in 1998.
There's also limited Pu240 available to make the RTGs.
Astronomers Discover Planet Identical To Earth With Orbital Space Mirror http://www.theonion.com/articl...
All hail the armchair asteroid mission planning experts. Why they keep hiring professionals to do these jobs is beyond me.
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.
About the same as a typical video gamer.
Do not look at laser with remaining good eye.
I think we've been spoiled by the various Mars missions, and having rovers lasting well beyond the expected lifetime. We should not assume that all missions will be like that. We should revel in the fact that the probe is working at all after 10 years in space, and that it wa sable to land on the comet at all.
What an insulting thing to say about the astronaut!
I think that's pretty unfair.
It was launched 10 years ago, and has been spiraling around the solar system doing fly-bys to get going fast enough to match speed ... and then it got close enough to land, even though it wasn't perfect.
I'm more inclined to think this is a demonstration of just how damned hard something like this is, and that no matter how much you try to plan for stuff, you can't know everything until after it's happened.
I think a bunch of whiny nerds saying this was poorly thought out is some pretty lame arm chair quarterbacking.
Tell you what, when your probe lands on a comet, we'll all line up to tell you what a shitty job you've done.
Oh, wait, you don't have a probe and wouldn't know how to make one, right?
Lost at C:>. Found at C.
No, the design and planning were rigorously thought out - certainly rigorously enough to withstand five minutes of bewildered pondering from a Slashdotter after the fact.
The actual problem here is that landing on a comet is really hard.
Why can't it back off and take another run at it?
Ask the guys at ESA. They could probably explain in great detail exactly what the probe is and isn't capable of and why they took the decisions they did after years of planning and cost-benefit analyses. They probably even have graphs.
systemd is Roko's Basilisk.
Come one, clearly some dude on Slashdot is better at landing on a comet than those people.
He's done it like twice in KSP.
Still more capable than a useless arduino in a shoebox that cost a billion euros.
And when something doesn't go as planned, as inevitably happens at some scale, we get to listen to people complaining about the useless person stuck there that costs 100 billion euros. An the question shouldn't be if a person is more capable than a $1 billion euro robot if the person would cost way more to get there, the question should be if a person would be more capable than 100 $1 billion euro robots. For quite a lot of science work, that is a hard sell, even if a significant fraction of the robots failed, because then we could send them to many different comets and adapt and do different things with them in ways that a person couldn't even do if they were there (e.g. new instruments that require more than just duct taping together parts a person would have).
MUPUS from Space!
Putting probes down on Mars as proved to be a difficult learning experience. This probe is demonstrating that landing on a comet or any similar body with very little gravitational attraction has its own set of issues.
My hunch is that landing on them will require a craft versatile enough to guide itself into a carefully controlled landing. It''ll have to approach slowly, maneuvering to find a level place and touch down very gently to prevent a bounce. Then rockets will need to fire allowing anchors to set into place. Maybe, just maybe, a chemical "superglue" type attachment might be better than a mechanical one, at least as a preliminary measure.
Unfortunately, a decade was lost with this particular learning experience. The next will have to be carefully researched and tested, so it works first time and every time.
Y'know, I realize that all the self-righteous "Papa knows best" crowd recently learned the term "Dunning Kruger", but casually tossing it out as a way to instantly shut down any discussion works about as well as complaining about "privilege".
More importantly - For all you know, koan works for the Mars Rover program, and has a legitimate right to mock the ESA's lack of foresight.
On a purely practical level - Yes, more instruments means more weight. But to have no maneuvering capabilities, not even the ability to flip itself over if it landed on its side, or make short hops around the surface - Keep in mind the gravity here - A tiny piston slightly off-center on each side of the cube would have added a few hundred grams and meant a billion dollar mission wouldn't die later today because of shadows, of all things.
Drilling and have it become dislodged for an hour or two, hopefully landing in a better place sounds like a feature -- I hope they fire the harpoons a few hours before the batteries are discharged to take the chance of repositioning it in an open area
Time to audit the books to see who pocketed the money a more robust design would have addressed.
I think you guys should play some Kerbal Space Program and see just how much more fuel you need at every stage just to put an extra kg of equipment on that lander.
"How hard would it have been to install a bright LED on the top that Rosetta could see from a few km away?"
If you were to drop the LED frequency into the radio spectrum you could reduce the power requirement further.
It's true that the landing was a phenomenal accomplishment, however ALL of the systems designed to secure the probe failed, and these failures had nothing to do with the nature of the comet surface. I wouldn't say this was poor planning. It was a failed engineering design.
Look, unless you're a friggin' rocket scientist, or believe they had additional information they didn't use ... summarizing anything as "the whole problem" is kind of childish.
Based on your vast experience of landing on comets after a 10 year journey, do you think you have a better sense of what the assumptions about the hardness of the ice should have been? Maybe you should have shared that with them.
Lots of smart people worked on this, took all they knew and could surmise, and made choices with the best available information, and using the technology and money available to them.
I'm sure as heck not going to say "well, if only they'd done this it would have worked". I know I'm not qualified to do that, and I'm quite certain most of us on Slashdot aren't either. In fact, I'm betting the people who are qualified are all thinking this was a monumentally difficult task. NASA isn't sitting around going "Ha ha!"
To me, even what they did is some pretty mind-boggling engineering. But in interviews I heard over the last few weeks, they still knew there were risks and uncertainties.
It sucks, but unless you're more qualified than the entire team who did this, you have to realize this is still an incredible feat.
I won't even claim this to be an accurate analogy: But this is kind of like hitting a target in China from New York, using a home made gun, in the dark, and while both you and the target are moving.
Me, I'll applaud the ESA and everyone involved. Success for this kind of engineering includes all of the stuff that got you there. Getting far enough to have a failed landing is still a huge undertaking.
Lost at C:>. Found at C.
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.
"It seems to me the design and/or planning of this mission were poorly thought out"
Is the funniest fucking thing I've heard all day. Do you have any idea how well thought out this mission was? FFS look at the trajectory it took 10 YEARS(!) to get to the comet. And you think they overlooked the fact that the comet is craggly?
Jesus-Dunning-Kruger-Christ.
http://www.esa.int/esatv/Video...
And Philae bounced twice, finally settling in two hours after first touching the comet, which is enough time for the comet to rotate almost 60 degrees. The two systems meant to prevent bouncing - the thruster and the harpoons - failed, so it ended up some kilometer away from the carefully chosen site. That we are getting any science at all after that potentially mission-killing news is just fantastic.
I'm hoping they make some last-ditch effort to have Philae try to jump over to another part of the comet to get more sunlight, though I'm not sure what kind of resources they have to try it. Can they command the drill and/or the legs to jab downward relatively quickly? Command the harpoons to fire? I don't know, but you can bet this will be part of the design on future missions. I actually did some work on this, which made hopping around a key part of the mission.
I doubt that anyone who worked in any serious capacity for the Mars Rover program would mock these folks. They know everything that could go wrong in ten years of space travel.
You're right. For a billion dollars, they could have built and launched an Iowa-class battleship, which totally would have landed robustly on any comet or planet that you'd like. And at 58,000 tons, could easily have stuck to the surface of any silly comet.
Because obviously, the only consideration in launching missions like these is robustness of the package.
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.
To be honest, the trajectory calculations aren't that difficult. It's fairly cut and dry math and there have been computer programs to calculate this stuff for decades. It's cool, don't get me wrong, and the margin for error is a lot smaller than trying to hit Jupiter, but it ain't exactly rocket science.
Wait...
We don't have a state-run media we have a media-run state.
I only hope my final moments can be so bold. . .
Sdelat' Ameriku velikoy Snova!
"It seems to me the design and/or planning of this mission were poorly thought out"
Is the funniest fucking thing I've heard all day. Do you have any idea how well thought out this mission was? FFS look at the trajectory it took 10 YEARS(!) to get to the comet. And you think they overlooked the fact that the comet is craggly?
Jesus-Dunning-Kruger-Christ.
http://www.esa.int/esatv/Video...
True, it's easy to throw snide comments at the people who designed this mission but until now nobody really even knew any details of what the surface of a comet looks like. Furthermore landing on Mars is difficult enough, the success rate for landings on the Martian surface is something like 30%. Getting a probe to rendezvous with a comet and land on the surface is a way bigger achievement. Finally I'm not exactly surprised that some systems failed after almost a decade in space. I just hope they manage to milk the maximum amount of data out of this probe.
Only to idiots, are orders laws.
-- Henning von Tresckow
That's a strange assumption. Whence did it come?
Well, a mannad mission to mars is estimated to need roughly 800 Mg of equipment lifted into space, and then slung out onto a mars intercept orbit. The orbit required for this comet intercept is thankfully pretty similar (it needs only to get around mars to do a gravity assist back to earth, for a few more gravity assists to get out to jupiter). But a mission to mars would take only 2 years, this requires 10. That means 5 times as much food, and I'd bet a bunch more equipment. So lets conservatively guess at 1.6Gg of stuff that needs to be lifted into space.
Meanwhile, the launch mass for the robotic longer was a mere 100kg. So, even if you assume that you can scale the amount of fuel needed to get all the stuff up there linearly (which you can't), you're looking at 16000 times the cost, i.e. $1.6 trillion.
To me, it appears that the above poster underestimated quite a lot, not overestimated as you'd like to believe.
They know everything that could go wrong in ten years of space travel.
...Except landing in a shadow in the most important 30 seconds of the mission?
Though overall, I agree, and offer the ESA a hearty congratulations - Well done! Just somewhat disappointing that the coolest part of the whole mission, while "technically" successful, won't get to do anything more than drill a few small holes.
It seems to me the design and/or planning of this mission were poorly thought out, it's obvious the comet has a rough surface, they knew there would be shadows.
The planning for this mission was started 30 years ago - in 1984; 5 years before the Berlin Wall came down, 7 years before the Soviet Union was dissolved, 3 years after the first IBM PC was released. This mission has been compared to "throwing a hammer from London and hitting a nail in New Delhi".
Imagine that - the IBM PC with its 16 KB of RAM was advanced, for gods' sakes! It may be that it is easy to sit in front of your top-of-the-bloody-range games PC and imagine that 'it can't be that hard', but the fact is that it would be very hard even today, and the fact that we actually have anything man-made touching the surface of an actual comet at this moment is mindblowing. It was only really designed to run a few measurements on its main battery, and even that was considered beyond what we could reasonably expect; the secondary battery and solarpanels were more of a "you never know, we might get lucky". This mission has already been a huge success.
The legs are 'springy' and can be used to hop the lander off the surface. The problem is that they can't tell the orientation of the lander. If it's in a cave, the legs might hop it deeper into shadow.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
What, everything didn't go 100% according to plan in a groundbreaking attempt to land a probe on a comet? Quick, let's easily write off the whole endeavor to seem cool!
You were critically hit for no damage. The bruise will look nice, and maybe the scars will make good party talk.
Is 'circle of uncertainty' like 'cone of shame'?
Maybe you should see if you can pass the Turing test before posting.
Faster! Faster! Faster would be better!
Only if the Rosetta spacecraft has a camera tuned to that frequency. Lower frequencies add more uncertainty to the measurements too.
I read the internet for the articles.
I know!! Its so simple: just land a little craft on a comet as it flies through our system! Come on people: its not rocket science!
Word game?
I think JSA is holding out to use Yamato on a mission where it's Wave Motion Gun could have maximum effect.
Hey Kerbal has taught me a lot about this kind of thing
1) Solar panels everywhere..hates it when I run outta power
2) Put a protruding strut on the top of the lander just in case your lateral motion causes you to topple
3) To stick the landing a bit of mystery goo can me most efficacious.
4) Get some mods...Philae looks like it was crafted from Vanilla parts.
Well, apparently they planned to launch with the gravity assists and eddies needed, and to intercept the comet's trajectory. That's macro-scale planning: "I'm going to go grocery shopping at Big K-Mart".
They apparently didn't plan back-ups for parts failure (thruster on top), landing anomalies (bounces around), losing track of the probe, or landing in shadow (couldn't make it mobile enough to move to a lighter place). They also didn't consider the cost in delivering a payload, versus the cost in delivering a slightly larger payload--two probes, which is less than two probes and two launchers and two fuel loads. That's micro-scale planning: "I need to carry a second credit card in my wallet in case I run low on cash or the first has a mag strip failure".
It's certainly easier to plan a mission that can get there and do its work if all goes well compared to if things go wrong. Realizing that something can be done and drawing up the plans to point-and-shoot isn't "well thought-out"; risks and contingencies are what make a plan well thought-out.
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The legs are 'springy' and can be used to hop the lander off the surface. The problem is that they can't tell the orientation of the lander. If it's in a cave, the legs might hop it deeper into shadow.
I understand why they haven't tried it yet, but if it's about to run out of juice anyway, there's no reason not to give it a shot.
It's a potential opportunity risk analysis problem: the panel was added to take advantage of the opportunity of greatly increasing your ROI by having a long-term operable probe.
Applying the small costs additional to add tracking or mobility so the probe can recover from landing somewhere unfavorable (there is an entire dark side of the comet) potentially has huge returns in additional scientific data gathered: even absolutely minor, unique data is data you can't get without funneling billions of dollars and years of space travel into a comet excavation mission, so any additional data gathered is billions of dollars cheaper than it otherwise would be.
If the probe turns out like the mars rovers--able to operate for months or years on solar power, possibly occasionally powering down for a few days or weeks to let the batteries recharge for laborious drilling and analysis--then your small additional investment pays enormous dividends. If the probe is simply able to gather more data than predicted, but the data is good and interesting, your small investment is still paying off. If the probe simply fails, the small additional investment costs you little compared to the vast base cost of the mission itself.
This type of analysis tells you when to capitalize on risk opportunities. If you can turn a 10% likelihood of gathering 1% additional ROI into a 95% likelihood by adding 0.001% to the cost, you do that. You should look at all risks and combine as much mitigation as you can to minimize the discrete cost of each and maximize the total opportunity exploitation and total risk mitigation, and then add contingencies (alternate plans) which take effect at possible cost (maybe you can do X and Y, and it's expensive to be able to do BOTH, but you can implement the capability to do EITHER and sacrifice the other for cheap), but only when the threat or opportunity presents itself in earnest.
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Back off and take another run? Think outside the box man. The obvious thing to do now that we have an orbiter circling the comet at 10km and can see it in exponentially more detail than we could have ever hoped to from earth.. EVER...is use the time machine to send that information back to the early 90's when they started designing the lander.
Seriously, have you seen the earth observations? They're like 8 pixels.
We're all glad you're here to share your wealth of experience in space probe design with us.
Despite the glitches, the fact that there is a man-made object currently sitting on the surface of a comet and beaming back actual pictures is flippin' mindblowing !
In that case they should have just edited the save file. I mean it's in JSON and everything.
I'm sure that in 1985, plutonium is available in every corner drugstore.
D'OH!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
In 1984 no one bought an IBM PC with 16k of RAM. 256K was normal, larger sizes less so, but not entirely unheard of. 640K was growing common within a couple of years, but the great RAM price spike of the late 80s (something like $1k a meg) put a little bit of a damper on that.
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
Oh, wait, you don't have a probe and wouldn't know how to make one, right?
You know koan works on the Mars Rover project, right?
He does? Really? Seriously? And he is still this clueless?
The planning for this mission was started 30 years ago - in 1984;
Do you have a source for that claim? googling Philae 1984 doesn't seem to turn up anything relavent.
Imagine that - the IBM PC with its 16 KB of RAM was advanced
The XT which came with 64K as standard and supported 256KB on the motherboard (and 640K through add-in cards) was released in 1983.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
The battery life is good enough for the primary mission which is to plunge a drill into the comet. After they've accomplished the mission they will probably try something, but give them time to analyze things and accomplish the primary goal before they try.
Keep in mind they try to jump and they might jump into deep space.
While I'm not sure how many football fans are here on Slashdot, there are always plenty of Monday morning quarterbacks.
Anyone know what the deal is with the pipe or rod looking object in the lower right hand side of this picture http://www.esa.int/var/esa/sto... />? It looks like it is embedded in the comet and is casting a shadow. I am suprised the tin hat people haven't taken off with this yet.
"It seems to me the design and/or planning of this mission were poorly thought out"
Is the funniest fucking thing I've heard all day. Do you have any idea how well thought out this mission was? FFS look at the trajectory it took 10 YEARS(!) to get to the comet. And you think they overlooked the fact that the comet is craggly?
If they knew it was craggly, then why were they surprised at how irregularly shaped it was. I remember them saying how they suspected comets would be much more smooth than this was and they had a tricky time trying to find good places to land.
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
They originally thought there would be no shadows because comets are very smooth and round. It wasn't until the Rosetta probe came close that they saw what it actually looked like.
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
Comets are now known to be hard as well and definitely not mushy.
THAT is the major finding so far.
Philae was expected to land gently on a frozen snow cone into which it would fire anchoring harpoons,
but it bounced a off a deep frozen ice mass (ouch) ascending 400m then touched down again
then bounced yet again until coming to rest in the shadow of a cliff. Awkward.
Scientists expected the comet’s surface to be powdery, allowing the lander to settle instead of rebounding back into space.
“It’s not a powder, it’s a rock, so it’s like a trampoline,
You go there and it ejects you immediately afterwards.”
The objectives of the science mission will probably be missed because hardware failure and reality trumping assumption.
Cryonics - Keep cool and carry on.
Because that's all science ever is, some scam to get money. Understanding the universe better is just an annoying side effect that they don't give a shit about.
This mission has been compared to "throwing a hammer from London and hitting a nail in New Delhi".
Why do all the comparisons involve a non-powered ballistic object like a bullet or in this case a hammer. The Rosetta probe does have thrusters on it and can adjust it's trajectory to hit the comet. It would be more like a heat seeking missile shot at a flare.
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
What state would the man be in after 10 years in space?
With adequate life support, as good as new,
Hardly. Cosmonauts returning from Mir after only one year in space could barely function once they returned to earth. I kind of doubt that anybody would physically survive 10 years in zero-G, even assuming they've survived the long-shot odds of no fatal spacecraft malfunctions in 10 years.
Not to mention that they would gone bat-shit insane by that time, after they realized that they've sat in a tiny tin can eating stale cat food and being blasted by cosmic rays for over a decade just so they get a sample of some crappy small-time comet; a job that could be easily done by a robot.
I would attribute it to not realizing one has taken their glasses off and become ... Captain Hindsight. Everything is easy to see after the fact.
In August 2015 the comet will be at its closest to the sun, it would be neat if the lander could just go to sleep until then ...
Launch mass of Rosetta was 3000kg (3Mg). The lander mass is 100kg. Only counting the mass of the lander and not counting the mass of the Rosetta craft that got it there is like only counting the mass of the astronaut and not the mass of the ship. You still have a large multiple, but 30 times less than you calculated.
So only 500X? Oh, well then. Let's get going tomorrow!
You're special forces then? That's great! I just love your olympics!
That's a little misleading. It's not like they would have locked down the design to use components in 1984. That's just when they started talking about the project. The design likely wasn't locked down until 5 years before launch or so.
I do not fail; I succeed at finding out what does not work.
Fifty-six hours after landing on the surface of a comet, Philae sent one more round of data about its new home across 310 million miles of space. Then, its power went out.
"@Rosetta, I'm feeling a bit tired, did you get all my data? I might take a nap..." read a message on the @philae2014 Twitter feed.
The Rosetta mission's twitter response: "You've done a great job Philae, something no spacecraft has ever done before."
All the experiments on board the lander had a chance to run and return information back to Earth. Philae's instruments scooped up material from the comet's surface, took its temperature, sent radio waves through its nucleus, and went hunting for hints of organic material. Cameras took the first panoramic images from the surface of a comet.
It has been a whirlwind ride for the lander, which was dropped onto the surface of the mountain-sized comet 67P/Churyumov-Gerasimenko on Wednesday morning. Two harpoons that were designed to tether it to the surface failed to fire, and scientists say the lander made two bounces before becoming stable. The first bounce caused the lander to go one-third of a mile into the air.
Friday morning, ESA officials expressed concern that the lander would not have enough battery power left to send back any more data from experiments it was conducting on its new, icy home.
When Philae landed on the comet on Wednesday, it had enough battery power for about 60 hours of work. Scientists initially hoped that it would continue to operate on solar power, but the lander seemed to have settled in a hole on the comet, where it was surrounded by rock-like structures that block the sun.
Stefan Ulamec, the lander manager from DLR, said the that one of the solar panels on the lander was getting about an hour and 20 minutes of sunlight a day. Two other panels got just 20 to 30 minutes a day, he said.
At a news conference Friday morning before the last signal was received, Ulamec said it was possible that scientists would not hear from the lander again.
"We are hoping to get contact again this evening, but it is not secured," he said. "Maybe the battery will be empty before it talks to us."
Happily, that turned out not to be the case. On Friday evening, ESA reported that all the science experiments had been deployed, and that the lander had been rotated 35 degrees in an attempt to get more sun on one of its larger solar panels.
There is a chance that as the comet flies closer to the sun, the increase in solar energy will allow ESA to communicate with Philae once again.
ESA officials say the odds of that happening are small, but with Philae, the little lander that could, anything is possible.
...I kind of doubt that anybody would physically survive 10 years in zero-G, even assuming they've survived the long-shot odds of no fatal spacecraft malfunctions in 10 years.
Oh, I think they'd survive just fine (appart from the numerous radiation induced cancers, natch), it'd be the whole 'returning to Earth' that'd cause problems.
Admit nothing. Deny Everything. Make Counter-accusations.
Oh, wait, you don't have a probe and wouldn't know how to make one, right?
Take a Rasberry Pi, a big ass Lithium Ion battery and some solar panels, attach that stuff to each other, then attach rockets to the bundle, point it at space and ignite.
I'm the best at space.
Admit nothing. Deny Everything. Make Counter-accusations.
Look, unless you're a friggin' rocket scientist, or believe they had additional information they didn't use ... summarizing anything as "the whole problem" is kind of childish.
Based on your vast experience of landing on comets after a 10 year journey, do you think you have a better sense of what the assumptions about the hardness of the ice should have been? Maybe you should have shared that with them.
Lots of smart people worked on this, took all they knew and could surmise, and made choices with the best available information, and using the technology and money available to them.
I'm sure as heck not going to say "well, if only they'd done this it would have worked". I know I'm not qualified to do that, and I'm quite certain most of us on Slashdot aren't either. In fact, I'm betting the people who are qualified are all thinking this was a monumentally difficult task. NASA isn't sitting around going "Ha ha!"
To me, even what they did is some pretty mind-boggling engineering. But in interviews I heard over the last few weeks, they still knew there were risks and uncertainties.
It sucks, but unless you're more qualified than the entire team who did this, you have to realize this is still an incredible feat.
I won't even claim this to be an accurate analogy: But this is kind of like hitting a target in China from New York, using a home made gun, in the dark, and while both you and the target are moving.
Me, I'll applaud the ESA and everyone involved. Success for this kind of engineering includes all of the stuff that got you there. Getting far enough to have a failed landing is still a huge undertaking.
Well, I think the whole problem was that they did not have a wizard on staff to solve every problem with magic.
Also, far as I know, their graviton phasor array had decohered somewhere along the journey.
Admit nothing. Deny Everything. Make Counter-accusations.
I don't think he made them up. I have heard of those numbers before.
The new right fascists are bilingual. They speak English and Bullshit.
If no one has told you yet today(which is doubtful) - FUCK OFF
The new right fascists are bilingual. They speak English and Bullshit.
I have heard that the ice in deep space is extremely soft
The new right fascists are bilingual. They speak English and Bullshit.
I fully agree except for the wording of the last sentence. How is this a failed landing? Not as good as we hoped for, sure, but the lander is not damaged, the basic scientific programme was completed, data sent. Now they could perhaps do more with the additional solar energy, but the landing was not good enough to do that. Yes, it could have gone even better, much better, but sying it's a "failure" is far too negative.
If they don't have it on powerpoint im not interested
The new right fascists are bilingual. They speak English and Bullshit.
Oh Fuck oFF
The new right fascists are bilingual. They speak English and Bullshit.
"To be honest, the trajectory calculations aren't that difficult"
First order calculations aren't hard. It's the myriad perturbations to both comet and probe trajectories caused by gravitational influences of various bodies which adds to the fun.
Space science is easy. Space ENGINEERING is bloody hard, and the environment is harsh on a scale which even people who work on these things have trouble comprehending (Disclosure: I work for a space lab with one of the best-regarded instrument engineering facilities in the world and we do have devices on the orbiter)
There are a number of ways the lander could have been built - all of which would probably have added more launch mass/operational complexity and reduced the science payload. This won't be the last comet lander and as a first one, it's informed a lot more than it's frustrated. As long as we're tied to making things as lightweight as possible there will always be compromises, especially when each probe is a one-off handbuilt design (even the "mass produced" birds are heavily customised)
With the best will in the world, by August 2015 the probe would be completely baked even in its current location.
Solar cells were a life-extension measure. The probe was designed to get all the essential science done in the lifetime of the batteries and the hope was to keep going for a few months after that.
At least the Iron Chicken didn't steal its legs for nesting material.
"The design likely wasn't locked down until 5 years before launch or so."
Which was around 2000-2001 - and space-rated semiconductors tend to lag terrestrial development by about a decade, more so for stuff which doesn't have the advantage of the earth's magnetosphere for protection.
We were still launching rad-hardened P90s in 2006. Many sub 200nm circuit elements would end up being destroyed (not just disturbed) by an errant cosmic ray (most often a near-light-speed proton or neutron, not a photon), which limits what's available, given that shielding from such things is virtually impossible in the allowable mass budgets.
Do you have a source for that claim?
Nothing more precise than the news broadcasts on BBC4 on the morning when the probe actually landed. Lots of talk about how many of the scientists involved had been involved from the very beginning, 30 years ago. You should be able to get more precise answers if you email BBC4's newsteam, there are quite good at responding.
Why do all the comparisons involve a non-powered ballistic object like a bullet or in this case a hammer.
Because it is a rather good comparison. Although the Rosetta has thrusters, for most of the 10 years it has taken to get to the comet, it was not moving under power, and in fact, unlike throwing a hammer from London to New Delhi, its trajectory was nothing as simple as a ballistic curve; apparently it passed by the Earth twice, and the 'nail' it was supposed to hit, was moving rather fast. Perhaps a better comaprison would have been playing billiars on an enormous table that wasn't flat, where all the bumps and valleys moved around and the target roaring across at the far end. The chances of ending up a million miles away from the target were significant.