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Mars Odyssey Completes Aerobraking
Cally writes: "Space.com reports that
Mars Odyssey has
completed aerobraking and is ready to begin its
main science mission. As the spacecraft has already produced exciting results before the start of the science mission proper, interesting data on the quantities of water in the Martian crust may be expected soon - not to mention that Odyssey provides another datapoint in the study of Gamma Ray bursts."
Here's the article:
January 11, 2002
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Mars Odyssey Mission Status
January 11, 2002
Flight controllers for NASA's Mars Odyssey spacecraft sent commands overnight to raise the spacecraft up out of the atmosphere and conclude the aerobraking phase of the mission.
At 12:18 a.m. Pacific time Jan. 11, Odyssey fired its small thrusters for 244 seconds, changing its speed by 20 meters per second (45 miles per hour) and raising its orbit by 85 kilometers (53 miles). The closest point in Odyssey's orbit, called the periapsis, is now 201 kilometers (125 miles) above the surface of Mars. The farthest point in the orbit, called the apoapsis, is at an altitude of 500 kilometers (311 miles). During the next few weeks, flight controllers will refine the orbit until the spacecraft reaches its final mapping altitude, a 400-kilometer (249-mile) circular orbit.
"The successful completion of the aerobraking phase is a major milestone for the project. Aerobraking is the most complex phase of the entire mission and the team came through it without a hitch," said David A. Spencer, Odyssey's mission manager at JPL. "During the next month, we will be reconfiguring the spacecraft to begin the science mapping mission." The science mission is expected to begin in late February.
During the aerobraking phase, Odyssey skimmed through the upper reaches of the martian atmosphere 332 times. By using the atmosphere of Mars to slow down the spacecraft in its orbit rather than firing its engine or thrusters, Odyssey was able to save more than 200 kilograms (440 pounds) of propellant. This reduction in spacecraft weight enabled the mission to be launched on a Delta II 7925 launch vehicle, rather than a larger, more expensive launcher.
JPL manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Principal investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, Texas, operate the science instruments. Additional science investigators are located at the Russian Space Research Institute and Los Alamos National Laboratories. Lockheed Martin Astronautics, Denver, Colo., is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. NASA's Langley Research Center in Hampton, Va., is providing aerobraking support to JPL's navigation team during mission operations.
Human colonization is quite unlikely due to the plant being so close to the Sun.
Mars is further from the sun, not closer, than Earth.
Mission endourance tests
Reduced gravity habitats
Alternate farming techniques
etc...
Some of the knowlege gained will help us go further from our home, still others will contribute to our lives here.
Astronauts are "test pilots".
.. the prior story about preliminary findings. This is not redundant: It is something that has mostly been ignored by official NASA press releases but has still made it into the mainstream media. I really hope that the failure of NASA to mention that they already have detected "large desposits of hydrogen" close to the surface means that they're waiting to confirm their findings, not that there's some dark conspiracy postponing any serious trips to Mars by decades in favor of sinking money into NMD, ISS and the Shuttle instead.
interesting data on the quantities of water in the Martian crust...
You know, doesn't this mean that all this other searching for extra-terrestrial intelligence is pretty counter-productive? If there's water right there on Mars, chances are there would be intelligent life there within a few billion years too. (It's the initial part of the thing that takes awhile...once you've got cells, the growth is like, exponential man.)
Instead, we're sending probes up there when we KNOW there's no intelligent life yet. It's like barging into the prenatal ward every few minutes while your wife's about to give birth to say "are you done yet?" Believe me, when she's done, you'll know!
At this rate, within the foreseeable future we'll have groped every planet capable of sustaining life with these stupid probes. Ever consider that under these conditions, intelligent life won't want to evolve? People like to be left in peace (that's why they get all fussy about the anal probes they constantly imagine aliens violating them with)...don't you think other would-be life might feel the same way?
This is not off-topic.
Which would you rather do, set up a colony for the first time a few months away or a few years away? At least with Mars, if something goes horribly horribly wrong, they'll only be a few days or months away, as opposed to lightyears.
Some have suggested that we colonize a small part of the sea as a training ground.
Anyway, PBS tends to re-run Nova episodes quite a bit where I live, so check your local listings - you might be able to catch it again real soon if you missed it the first time.
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I mean, you could probably come up with a method of generating some mechanical energy in the process of aerobraking, but it seems to me that we're dealing with a mechanical energy which wouldn't do you a whole lot of good in space -- after all, fuel isn't the problem, it's a lack of something to push against.
So, am I missing something here, or did you just post that link to look smart?
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
Is regenerative aerobreaking feasable at our technology level?
:-)
It would have to gather up reachtion mass plus generate power to use it. Perhaps a scoop and long cables to use the planets electro-magnetic field to store up power.
Nothing we have comes close to pulling off this sort of trick.
Anyway.. why bother about getting it back? Who would want it? I mean, my last car lost enough resale value in the past few years.. the trade-in value for a vehicle with a billion miles on it would really suck.
After a nearly perfect launch, 2001 Mars Odyssey is on its 400-million-mile, six-month journey to the red planet. The spacecraft will primarily search for water on Mars but it will also seek 19 other chemical elements and measure radiation. NASA, just barely holding the budget-cutters at bay, needs to recover from two previous Mars failures: the Mars Polar Lander and the Mars Climate Orbiter. If everything works, Mars Odyssey will spend two years circling the planet while taking measurements and readings. The mission was already providing remarkably sharp and dramatic views before and during lift-off with two cameras attached to the Delta 2 rocket, one facing up and one down.
NASA:
http://mars.jpl.nasa.gov/odyssey/
Space.com: Space.com
Look, spending the resources we currently expend on space travel isn't going to contribute substantially to work peace (nor hunger, nor overpopulation, nor keeping people from being laid off).
On the other hand, the greatest points of human progress have historically taken place in two times -- exploration and war. Both of them create necessity, which is (of course) the mother of invention. I assume you'd rather avoid war, as would I, so exploration seems like a good investment.
Besides, its our nature to do this sort of thing. That's why people weaved reed boats, why they sailed before they could figure their position with any certainty, why we, as a race, have always struggled to see what's over the next hill.
The small-minded idea that you could solve disease, hunger and war by supressing the instinct to explore and becoming universal xenophobes is both juvenile and foolish -- at no time in history has anything like this proven true. Indeed, the worst times tend to be those where we stopped being curious -- dark ages, anyone?
I don't mean to be too brutal, but your half-thought-out assertion in this area offends me.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
Actually, the preliminary exciting results would be that it didn't crash into the planet or just disappear.
Too bad they didn't use regenerative aerobraking...
Regenerative areobraking? What do you want them to do - put paddle wheels on the probe?
Okay, your comment was stupid. You probably just had a twitchy "Submit" finger and wanted to get a comment in there early. I can understand that. What is ridiculous is that at least two morons out there actually thought is was "Interesting" enough to mod it up to +4.
Would whoever did that please smack the back of their head for me? Thanks.
Let me try to answer my own question:
Mars is a place with resources; there's an atmosphere and useful raw materials are present. You could make livable buildings, air, even grow food -- all you need is enough energy and you can do a lot of things based simply on what we already know is there.
The moon, on the other hand, is relatively barren. Living there would be a lot harder, especially in terms of the no atmosphere thing. You have to bring just about everything you need to the moon, but could live reasonably on Mars just by moving power there and investing a lot of elbow grease, building infrastructure and etc. Potentially, you could make the surface of Mars the second-safest place in the solar system, able to survive even thtough years of zero contact with earth.
Just a thought, though, that it you want *practice*, the moon's probably a better place to start.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
There's obviously no such thing as "regenerative aerobraking." My comment was mainly about the fact that by using aerobraking, they cut a few million off the launch costs. That's going to be invaluable in the future, as science budgets continue to be stripped to the bone.
Why anyone took the incredibly dry witticism at the end seriously is beyond me. Perhaps I should have used more vermouth.
I've seen astroturfing on Slashdot before, but this is a pretty lame example of such.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
So they are at least investigating if (and when) human colonisation is feasible.
For the more general question of why NASA is mucking about in space, have a look at some of the FAQs.
It seems one of most common questions is 'Can I apply to take a ride on the Space Shuttle?' (A very polite 'No' in case you were wondering. Presumably the Russian Space Agency have a different answer to this one
It's that old (but valid) argument that humanity has all its eggs in one basket. If some son-of-a-bitch pushed the button here on Earth, it's all she wrote for our race.
No, you're not all for exploration. If you were, then you'd understand that exploration is a reason to do it in its own right. If you need to have a reason to "explore," that means you're against it and looking for a better reason to get you up off your ass.
With that being said, lots and lots of real estate that's easier to launch from (in both the surface-to-orbit and extra-solar senses of the words), as well as both known and unknown natural resources. Oh, and no tree-huggers if you want to get industrial up there.
I swear, Slashdot could post the most mundane story about space exploration, and it still draws the same old complaints about this and that, the usual space trolls. I'm just going to respond to them all here for future linkage.
1.) If you have difficulty understanding exploration for it's own sake then you aren't "all for exploration."
2.) If we knew of all the ways we could use and develop (insert name of celesial body here), then we wouldn't need to explore it, now would we?
3.) Yes there are people dying in (insert Third World country here) of (insert Horseman of Apocalypse here). The reasons for these deaths are purely political in nature. Money is not the solution to all problems just as it isn't the root of all evil. If anything it becomes a scapegoat for the real causes of strife. I don't see how not spending the money on space exploration and letting Congress (of all people) spend it on (choice of one or more of the following: junkets, political campaigns, television commercials, Jesse Jackson, economic incentives, UN resolution, Jimmy Carter, "peace-keeping" expedition) to "make the world a better place" is really going to change a damned thing. (Name of two opposing ethnic, religious, or political groups here) need to talk to each other, and dangling money in front of their noses isn't going to get them to do that, it will just get them to chase that money.
4.) As for education reform, go talk to your state and local governments. If you don't know why you should be talking to them instead of the federal government, then you are an example of how badly we need education reform.
5.) Do you have any idea how small a percentage of the federal budget is spent on space exploration?
6.) We are NOT on the verge of nuclear war! At worst, the only countries on the verge of nuking each other are (names of two nuclear powers that didn't sign non-proliferation agreements)! And they aren't the ones sending up these probes, are they?
7.) With all the problems there are in the world today... why would you want to live in the world today? (name of celestial body) looks like a damned good alternative to me!
You think it's easy to make space probes that work perfectly?!
They have to launch these fragile robots through the harsh interplanetary void, always mere inches -- no wait, was it centimeters? maybe cubits... fathoms? -- from disaster...
I'll be chuckling over that for days...
How about regenerative ferrobraking? Shoot iron slugs from an accelerator at the spacecraft, and have it catch them in a magnetic field and throw them back to the accelerator. No propellant loss, spectacular efficiency, works for starting as well as for stopping. Accuracy is problematic.
Nasa once again launched a spacecraft at Mars. However, due to inaccurate calculations, the spacecraft missed its target and instead settled in a stable orbit, unable to crash into the planet and achieve its intital objective. A preliminary investigation blames a slight miscalculation due to the improper use of significant digits.
Mission planners are uncertain how to proceed now that the mission has been officially declared a failure. "We now have a $250 million piece of equipment uselessly orbiting the planet." A small group of scientists has declared the mission "not a total loss" as this might present a rare opportunity to study the planet before the orbiter crashes into the planet naturally at some later date.
-Restil
Play with my webcams and lights here
Mmmph. Maybe it was supposed to be funny. In any case, any time you have a heat differential (between the inside of the craft and the outside, heated by atmospheric friction) you can theoretically use that to create power. But unless it's nescessary, adding that ability would only increase weight, which is the problem aerobraking is supposed to be solving in the first place.
As the basic rule, all measurements are metric this time. Some of the mechanical components are in US measurements simply because the aerospace industry has always made them that way and a special order of metric components would be much more expensive. However, every time a US measurement is used it is explicitly accompanied by it's metric conversion in the spacecraft's documentation.
What you say is absolutely true of space exploration. It is slightly less true of commercial/ military uses of space. I have a problem with the two sharing one budget. Space exploration itself is very cheap, the most expensive probes cost pennies per inhabitant of the Earth. Space commercialization is considerably less cheap. The two do overlap somewhat (launch devices, technology development, etc) but it is high time that we had a seperate, ongoing committed budget for space exploration.
So long and thanks for all the fish . . . !!!
It seems one of most common questions is 'Can I apply to take a ride on the Space Shuttle?' (A very polite 'No' in case you were wondering. Presumably the Russian Space Agency have a different answer to this one ...)
Why the Russians will sell space rides and NASA won't: the Russians aren't worried about being sued if the thing explodes.
...a truly excellent hard-SF book, in which a gamma-ray burster plays a major role. The math gets deep at times; just keep slogging through it and your mind will be expanded. (Possibly painfully.)
You cannot apply a technological solution to a sociological problem. (Edwards' Law)