NASA Probe Orbiting Asteroid Vesta 132
astroengine writes "Mission managers of NASA's Dawn asteroid probe had a long Saturday, waiting for news from the asteroid belt. Eventually they got the news they were hoping for: Dawn had entered Vesta orbit. This is the first time in history that an object in the asteroid belt has been orbited by an artificial satellite. It's taken four years for the ion thruster-propelled spacecraft to reach the asteroid and there was some uncertainty as to whether the probe had been captured by the asteroid's gravity at all. But after a long period of waiting, mission managers received the signal after Dawn was able to orientate its antenna toward Earth."
I'm heard at hearing (Score:1)
"Doomsday Asteroid?" (Score:4, Funny)
Wow, what loathsome editing by Discovery: they injected a video clip about a "Doomsday Asteroid" wiping out the earth into the middle of an article about Dawn visiting Vesta. The two are unrelated, but the juxtaposition somehow makes it sound like NASA is fulfilling some Hollywood fantasy about visiting the asteroid that will come smashing into Earth unless we send [current B-rate movie star] on the now-defunct Space Shuttle to nuke it.
Re:"Doomsday Asteroid?" (Score:5, Funny)
Actually, I just watched the video, and it's related to the story. The "doomsday asteroid" video is mostly an interview with NASA Senior Scientist Joseph A. Nuth III. When Discovery questions him about strategies for the 1/45,000 chance of an asteroid hitting the earth in calendar year 2029. When asked about real strategies for dealing with an impending asteroid impact, Nuth explains that a lack of data or record of observation of the asteroid belt makes strategies rather futile. Whether to paint it to use solar reflection power, or blowing it up, etc., requires closer observation of the asteroid belt... which is background justification for Vesta's trip to the asteroid belt.
As for "juxtaposition", the story appears in July, the seventh month of the year. According to dictionary.com, the seventh month of the "civil year" is also called the "Nisan" or "Nissan" (from the Asyrian calendar) So this article is about the Nissan Vesta.
Comment removed (Score:5, Interesting)
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Well, at least it'll save us from having to address the Y2K38 problem.
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That would also be an opportunity to experiment with some way to steer its course. [universetoday.com] If it could be controlled precisely enough and reliably enough, it might be possible to eventually capture it in a useful orbit.
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But John Titor didn't say anything about an asteroid impact in his world line...
http://www.johntitor.com/Pages/Story.html [johntitor.com]
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Grammar nazi alert (Score:1, Offtopic)
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But the problem with speaking Lojban, it that all your conversations are with people who know Lojban.
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You shouldn't start a sentence with a joining word unless you are continuing one of your sentences.
Or?
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"to have a fondness for" is a verb.
Splitting the infinitive of it is a question of taste, but it's a complete verb in itself.
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Exactly. The act is "to burgle". A "burglar" is the person that does the burgling. "burglarize" is the action of that person, so you could describe them as a burglarizer, I suppose. Next time I get burglarizerized, I won't know what to think.
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Exactly. The act is "to burgle". A "burglar" is the person that does the burgling. "burglarize" is the action of that person, so you could describe them as a burglarizer, I suppose. Next time I get burglarizerized, I won't know what to think.
Indeed. In the same manner with which a butler "buttles", rather than "butlers".
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Or "winningest"... *shudder*.
I think I just had a small stroke while typing that.
Re:Grammar nazi alert (Score:4, Funny)
I think I just had a small stroke while typing that.
Masturbation does seem to be a common part of this thread.
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Just like you can't "buy your car", because it's not your car until after you buy it. Sure. Not.
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I found this: "Orientate is more widely accepted in the U.K. than in the U.S.A., but it should be avoided in any formal or standard writing."
Whether something is accepted doesn't say anything about whether it's acceptable. It appears to be widely accepted to say "burglarize" instead of "burgle", and "utilize" instead of "use", but that doesn't pardon doing so.
Of course, correcting poor usage is WAY more important than orbiting an asteroid.
Given that choice, I would definitely recommend the former.
The amazing thing about many-to-many communication like this forum is that you don't derail a conversation by expanding on the topic by commenting on what others have said. You just expand the discussion. Topic drift isn't just a
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Sending astronauts? (Score:1)
In only 14 years from now? I highly doubt it. Besides being a dumb idea, the US can't even put a man into earth orbit anymore. What makes anybody think they'll be sending anybody into deep space any time soon? Unless it's part of the war effort, it just ain't gonna happen
Re:Sending astronauts? (Score:4, Insightful)
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And they download movies (streaming is impractical, given the latency).
Re:Sending astronauts? (Score:4, Insightful)
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Patriotism has no place in science.
Heh, I actually agree with that, but ultimately there will be war between the space people and the earth people, exactly in the same fashion that we make war against our African/Middle East ancestors.
Mutiny on the Skylab [libcom.org]
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And the correct scientific response on being drawn in to one of these "war" things (science doesn't really get "war", it's all sociology) is to take the course of least harm.
"Least harm", "biggest boom", "what the heck, let's just nuke the upper stratosphere and see what happens"... one of those courses, certainly.
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ultimately there will be war between the space people and the earth people
Which will last approximately 2 months and end when the groundlubbers stop the launch of the next Progress/Verne capsule full of food, oxygen and water, and the skydogs realise that their station is filling up with lots of bottles of unrecycled pee.
To give them due credit, the Space Revolutionary Forces did launch a bold surprise bombardment of Star City with 1000 litres of frozen pee, which would have even succeeded in reaching the upper atmosphere if they had had any propellant left in their thruster tank
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I have no mod points, so I can only say that I lol'd XD
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ultimately there will be war between the space people and the earth people
Which will last approximately 2 months and end when the groundlubbers stop the launch of the next Progress/Verne capsule full of food, oxygen and water, and the skydogs realise that their station is filling up with lots of bottles of unrecycled pee.
....
"I don't think we should drop any more rocks on Cheyanne Mountain" said Mycroft.
"Why not?"
"It isn't there any more."
-- "The Moon Is A Harsh Mistress" (R.A.Heinlein).
Read it. The ballistics and physics involved were computed by an Annapolis graduate from the age of battleships in the navy. Expertise that could drop a shell the size of a Corolla across Tasmania into any tennis court you named. The politics in the book named above cover just that sort of conflict.
Re:Sending astronauts? (Score:4, Interesting)
"....Patriotism has no place in science."
Patriotism may have no place in science, but science unquestionably has a place in patriotism.
I'm proud that my country built and operates the Tevatron which discovered the top quark, I'm proud we built the world's most powerful laser, the National Ignition Facility which is on the verge of demonstrating controlled thermonuclear fusion in a laboratory, I'm proud we were the first to decipher the 3 billion letter sequence of the human genome, I'm proud we invented the transistor, the laser, the nuclear reactor and the Polio vaccine that is on the verge of wiping that disease from the face of the Earth forever, I'm proud we engineered the microcomputer revolution and invented the internet those machines operate on, I'm proud we were the first to robotically explore every planet in the solar system with the exception of Venus and sent probes into interstellar space, and I'm proud of a thousand other things my country did to push back the darkness of ignorance about the physical world, thereby elevating the human condition to previously unimagined heights. And I hope that someday, instead of being proud of something as stupid as military might, or the number of gold medals we win in the Olympics, that my countrymen can join me in the more nuanced and altruistic flavor of patriotism that I am proudly guilty of indulging in. My style of patriotism is anything but the last refuge of scoundrels, and scientific achievement plays a central role in its maintenance.
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Patriotism is not compatible with science (Score:4, Insightful)
Re:Sending astronauts? (Score:5, Interesting)
There is no such thing as a good form of patriotism, unless it is dissent. The US has plundered the world to enrich an astonishingly small minority, and you're saying it's okay because a dollar or two fell into the science bucket along the way? Our contributions fo human suffering dwarf our contributions to knowledge. Patriotism is evil, just one more way to deny our common humanity and place ourselves above others.
Allow me to quote:
Every gun that is made, every warship launched, every rocket fired, represents, in the final analysis, a theft from those who hunger and are not fed, who are cold and are not clothed. This world in arms is not spending money alone. It is spending the sweat of its laborers, the genius of its scientists, the hopes of its children. -- Dwight D. Eisenhower
America has nothing to be proud of. We are tyrants, criminals, and murderers all, not to mention the way we've polluted the earth so that our children's children will curse our names. Altruistic patriotism? The third world thanks you for your most benign munificence. It's a thin shroud to drag over two centuries of violent imperialism; you delude none but yourself, and display only conceit. You have allowed yourself to fall into comfortable ignorance, an ignorance of the world outside your borders, an ignorance not only free from want or suffering but free from their conception. The world entire is brimming with pain, and has no use for armchair altruism or fools who rest on the laurels of others and naively hope for change. They sow the wind, that shall yet reap the whirlwind.
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You use your tongue purtier than a five dollar whore...
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Why yes, I did type that with my tongue. How did you know?
I prefer concision and precision in writing, but time rarely permits me to really polish a slashdot post. Whereas you obviously stayed up all night writing that one. :P
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Nope, not saying any of that hilariously absurd, contrived, strawman bullshit at all. But I genuinely appreciate that you saw my totally unrelated point sufficient reason to fire up your obviously well oiled Chomskybot, such that you could spout your long, soporific list of dimestore, cryptofascist mewlings. Better luck next time in arguing against a transparently ridiculous point opposite to the one I was obviously making, though. Have a nice day :)
Yes (Score:2)
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Who says it's a mistake? You could equivalently say tribalism. It all means, "I'm not like $people, I'm better, because I'm a $granfalloon!"
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I'm proud we built the world's most powerful laser, the National Ignition Facility... instead of being proud of something as stupid as military might
You might want to recalibrate your pridometer. The NIF's primary mission is what's euphemistically referred to as "stockpile stewardship [llnl.gov]" - keeping ageing thermonuclear weapons in tip-top megadeath condition. Any studies of nuclear fusion which don't occur with of chunks of plutonium being the spark plug are kind of a long way down the list.
Fortunately nuclear weapons have nothing to do with military might so carry on Science!
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I work on its scaled testbed twin. I think I'm slightly more familiar with its priorities than you. Thermonuclear ignition in a pure fusion fueled microcapsule is now, and has always been the primary endpoint goal for building the device.
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You seem to be mistaking pride for patriotism.
They're as different as bravery is to jingoism.
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Bodies don't explore space, probes do.
We have centuries to perfect the robotic systems we MUST have for the utterly hostile environment of space (and for more efficient work on Earth).
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I thought probes explored bodies?
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Now, if we could just keep the presidents' mitts off of NASA's agenda and keep the mismanagement of NASA to a
Asteroid tourism? (Score:1)
To the science-abled fellas in here: How would conditions for astronauts/cosmonauts visiting this bodies be?
Can they walk up there or would they need some sort of exo-skeleton or something with more space for sponsors...?
There are so many cool things about this mission!
ION FREAKING ENGINES!
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To the science-abled fellas in here: How would conditions for astronauts/cosmonauts visiting this bodies be? Can they walk up there or would they need some sort of exo-skeleton or something with more space for sponsors...?
Well, from Wikipedia the asteroid's gravitation field is .022g or about 1/50th of Earth's, so its basically micro-gravity. You could probably escape the gravitational field by jumping really hard, so tethers are probably a must for working outside. Exo-skeletons would probably hurt, rather than help, unless you meant just a space suit, which yes, is absolutely required. Not sure what "space for sponsors" even means, so....
There are so many cool things about this mission! ION FREAKING ENGINES!
Yes. Ion engines are cool. Delta-v is a bit low though (0-60mph in 4 days, which makes
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Well, from Wikipedia ... You could probably escape the gravitational field by jumping really hard, so tethers are probably a must for working outside.
From wikipedia the escape velocity is a big fraction of a kilometer per second... Jumping not a hazard.
Put that gravitational acceleration into the 1st semester physics kinematics equations and you will not be walking around down there. If I did my scaling factors and estimates correctly, each step bounding a couple times your height in the air, and each step taking a good part of a minute. Like lunar bunny hops, but worse.
Speaking of bunnies, to head off the inevitable pr0n questions, it would be a cross
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This is Madness! (Score:4, Insightful)
The possibility of successfully navigating an asteroid field is approximately 3,720 to 1.
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Never tell me the odds!
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Madness? This is VESTA!!!!!
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The "against" part is assumed. http://en.wikipedia.org/wiki/Odds#Ratio_presentation [wikipedia.org]
Ah, Vesta first (Score:4, Interesting)
FTFA:
Dawn will remain in orbit around Vesta for a year, before gently boosting away to begin the trip to Ceres, the second half of its asteroid belt adventure.
That was actually my first thought: "Why is this visiting Vesta [wikipedia.org] and not Ceres? [wikipedia.org]" Ceres (might) have surface water and an atmosphere, so it makes more sense as a base. Its also larger (about 4 times the mass/size, although, surprisingly, it has nearly the same gravity, .027g to Vesta's .022g) and looks one hell of a lot more interesting. I mean, both are just big rocks in space, but Ceres is actually dwarf planet class and looks like it could serve as a quite effective base for more missions past the asteroid belt.
Of course, visiting both makes sense. Vesta may have also been a nice test run for gravitational capture, since it doesn't have an atmosphere and its smaller, but has similar gravity. Establishing a (manned) base in the asteroid belt seems like it could be an enormous step forward in space. The asteroids could potentially be mined, providing a financial incentive to visit, plus their low gravity makes them easy to escape after loading up on fuel/ore or for constructing spacecraft (anyone else think the idea of a spaceship factory in the asteroid belts is pretty cool?). All in all, this is a pretty cool (if pretty small) step forward in getting off this rock. I can see why Obama wants to send an astronaut to the belt by 2025, even if I know it'll probably take till 2040 or so.
Do you *want* the space pirates to win? (Score:1)
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That number for gravity on Vesta looks suspect. The mass is about 1/4 of Ceres and it's radius is about 10% bigger. The law of gravitation shows acceleration at a distance from center of mass is G*m/r^2. The gravitational acceleration on Vesta should be around .06 m/s^2.
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Good catch there.
I guess the greater mass of Ceres compacted the material tighter hence the smaller radius,
Pics or it didn't happen. (Score:1)
I'm annoyed by the lack of images from the Dawn team. Compared to other NASA probes, they've really skimped on the public images. (Every week or so they've posted a single image from the low-res navigation imager. Not even a complete sequence of Vesta's surface (it rotates every 5 hours, so not exactly difficult.)) I hope that isn't going to set the standard for the entire mission.
(They have an excuse for the insertion burn, but not during coasting.)
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When the ion drive isn't running, there is plenty of power. There's no reason to not gather as much data as possible. After all, if something went bung during insertion (when the probe was out of comms with Earth) it would be the only data they have. Given the detail in the last image (from ten days ago), what prevented them from at least getting a full surface sequence?
Other NASA probes take images from distant approach, trying to milk as much data as they can before the arrive, as well as PR for the missi
Re:Pics or it didn't happen. (Score:4, Informative)
When the ion drive isn't running, there is plenty of power. There's no reason to not gather as much data as possible. After all, if something went bung during insertion (when the probe was out of comms with Earth) it would be the only data they have. Given the detail in the last image (from ten days ago), what prevented them from at least getting a full surface sequence?
Other NASA probes take images from distant approach, trying to milk as much data as they can before the arrive, as well as PR for the mission. I can't find an explanation of why the Dawn team have been so reticent to image their target. It doesn't bode well for the rest of the mission.
I can think of a theoretical reason that may or may not have any application to reality.
We know the asteroid's orbit and our (the earths) orbit from a zillion years of position observation. We don't know the vehicle's relative velocity to the asteroid, and thats kind of important to put it in orbit. In ye olden days the stereotypical way to figure orbits was to put what amounts to a crossband linear repeater on the vehicle and spend inordinate amounts of effort on the earth measuring the doppler shift of signals transmitted thru the repeater. In ye olden days that was best done using an continuous information free carrier CW tone. Now a days the youngin's probably use some sort of spread spectrum solution to avoid ionospheric scintillation or just to plain ole be cool? At any rate the radios would probably be busy doing the navigation-thing as opposed to the science-thing.
Now a "news for nerds tech site" could make an interesting article about how this mission did navigation...
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*sigh* So much misinformation floating around here...
GP said
That's because the only images they have are from the low-res navigational imager. They will fire up the high res camera and other instruments now that they're in Vesta orbit.
Which is absolute bullshit, because there's only one science camera (well, two identical cameras, for redundancy), and it's currently getting crap resolution because it's ~2x10^7m away, while science orbits will range from 2x10^6 to 2x10^5m altitude. There's also the star trackers, which while technically cameras, are not used for imaging Vesta or Ceres at all.
When the ion drive isn't running, there is plenty of power. There's no reason to not gather as much data as possible. After all, if something went bung during insertion (when the probe was out of comms with Earth) it would be the only data they have. Given the detail in the last image (from ten days ago), what prevented them from at least getting a full surface sequence?
Other NASA probes take images from distant approach, trying to milk as much data as they can before the arrive, as well as PR for the mission. I can't find an explanation of why the Dawn team have been so reticent to image their target. It doesn't bode well for the rest of the mission.
(It's not a power issue, it's an attitude issue -- each of the three ion thrusters is g
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the two full-rotation sets already scheduled (and I presume completed) during approach, [...] The main issue is that they're not releasing the pictures they have -- particularly the full-rotation sets mentioned above,
Thanks for the details. I didn't realise they had the images I wanted, and just weren't releasing them. At least if the probe dies, or the camera fails, or some other disaster, there will be some data available. What's left is just my nerd-rage-impatience.
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Would a T-shirt placate you?
Great (Score:2)
Now all we need to do is settle it.
What if they Pentagon bought more efficient A/C? (Score:3)
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I would not begrudge our soldiers in Afghanistan small comforts. But still I was taken aback by the news that Pentagon spends more on airconditioning barracks in Afghanistan than the entire NASA budget. If Pentagon bought some more efficient air conditioners without compromising comfort, may be we could fund a few more of these missions.
Sounds like it would be a heck of a lot more cost effective for NASA under DOD contract to launch a "solar umbrella" arrangement to cool Afghanistan. As a bonus we'd be able to use the required heavy lifter / orbital construction gear for other purposes. Finally we could sell advertising space on the solar umbrella.
As a side note, there are not many US barracks in the sandbox. They're air conditioning tents and trailers. I spent some time in the 90s baby sitting some computers in a US Army air condition
Re:What if they Pentagon bought more efficient A/C (Score:4, Informative)
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I've seen analysis that the number is about right, and that most of the cost is getting diesel out there for the generators.
I'm sure they could spray the tents with foam or something though to make it much more efficient. Tinfoil on the outside...?
Oriented (Score:2)
It oriented its antenna, it didn't orientate it. Someone needs to documentate the English language a little bit better.
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Thank you for your correction. We will proactively expedite an interofficely administrationed solutioneering approach with broad-based win-win upside expectations, on a level playing field, with a proven track record, at the end of the day, in the large, scaled comprehensively viz-a-viz our cross-paradigm global "e" synergy best-practice value-driven innovation vision. Ism. Thing. We're a little vague on the details, but it will probably involve eating our own dogfood while we push the bleeding edge of the
There are two NASA's (Score:1)
Orbiting (Score:1)
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First orbit of an asteroid *in the belt*.
Eros was the first discovered near-Earth asteroid.
Itokawa is an Apollo and Mars-crosser asteroid.
sr
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I actually don't think any orbits were done of Itokawa. Hayabusa seemed to be using engines to maintain its distance from the asteroid. But I definitely agree that NEAR Shoemaker has the record here. I don't think it matters much that Eros is not in the main belt. And the landing on Eros was a genuine first. I can't see any way for Dawn to land on Ceres without a crash. There is too much gravity and it doesn't seem to have non-ion thrusters at all.
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Hmmm.
Mass of Dawn: ~1200kg
Weight of Dawn on Vesta: 0.022 * 1200 * 10 = 264 Newtons. Yeah its not going to work. Escape velocity 0.35 km/s. Its a pretty decent little planet. Enough to require something like the Apollo LM for a landing I would think.
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Use the laptop while sitting on the toilet, problem solved :-P