Odyssey Arriving at Mars Tonight 195
moloader writes: "Odyssey will arrive at Mars on October 24, 2001, 0230 Universal Time (October 23, 7:30pm PDT/ 10:30pm EDT). As it nears its closest point to the planet over the northern hemisphere, the spacecraft will fire its 640-newton main engine for approximately 19.7 minutes to allow itself to be captured into an elliptical, or looping, orbit about 20 hours long. Go Mars!"
Spectrometer (Score:1)
Unexpected.. (Score:1)
Now here's the ultimate sequel!
Re:Unexpected.. (Score:2)
640 Newtons (Score:4, Funny)
Re:640 Newtons (Score:1)
Geez, if I had 640 Newtons, I know where I'd be spending the afternoon...
Re:640 Newtons (Score:1)
Apple Newton PDAs are nifty.
Re:640 Newtons (Score:1)
Actually, the NASA [nasa.gov] page says:
The engine provides 695 newtons, or 156 pounds of thrust.
Weird. I wonder where 640 came from?
Re:640 Newtons (Score:3, Funny)
It has tem, but they're not usable. The transmitter is locating after the 640th Newton, and using noncontiguous thrust would put it in a tailspin. So although all 965 are installed, the last 25 aren't useable. (however, there is speculation that it may be possible to make a TSO system: Terminate, Stay in Orbit., to use the extra Newtons. [Failing that, they'll be wrapped in cookies as snacks for the martians.]).
hawk
Re:640 Newtons (Score:2)
yes, I never cease to be amused by the moderations on my posts. Heck, it's one of the few reasons to still bother with slashdot
however, I note that quite frequently, the resulting moderation is something other than was selected . . . and not always in the correct direction . . .
Re:640 Newtons (Score:2)
I definitely agree that the original moderation was funny.
On the emacs thing, little brother saw the topic, along with the taco's near-invitation for vi-emacs flame wars. Little brother saw that, and claims to have nearly wet his pants laughing upon noticing it was me that took the bait (with a well crafted comment, if I do say so myself
hawk
Re:640 Newtons (Score:2)
>
> by [amorphis] on 11:51 AM October 23rd, 2001 (Score:0, Offtopic)
> ([26]User #45762 Info)
>
> funny, but whomever modded that up as "Informative" is smoking crack.
Hey, I think we found the moderator.
OK, crack-addled moderator, we know you don't want to be commented on, but the first step is admitting you have a problem. If I can stop practicing law, you can stop moderating on crack
hawk
Re:640 Newtons (Score:4, Funny)
DOS. NASA's been under a bit of a budget crunch and...
:)
Re:640 Newtons (Score:3, Funny)
Hope they used the right metric ... (Score:2, Funny)
Re:Hope they used the right metric ... (Score:5, Funny)
think about it (Score:2, Funny)
Re:think about it (Score:1)
Re:Give NASA some respect! (Score:2, Interesting)
What the fuck? Who was in charge of them? Jesus, do you work for them or something? Unbelievable!
more than just NASA in the history of space.... (Score:2, Informative)
"They are the only organization that's consistently flying commercial payloads to the orbit. "
Hmmm, I think the guys at ESA may beg to differ. I think the guys on the Space Station are probably grateful that a place a wee distance from the USA called the Baikonur Cosmodrome, Kazakhstan exists and regularly sends up Soyuz taxis. I reckon there's more than just NASA in the history of space.... (not to belittle their great work, but have some perspective, eh?)
BTW is it only the Americans who use imperial rather than metric units, or are there other countries who also use a non-metric measuring system?
Re:more than just NASA in the history of space.... (Score:1)
Just to be on the safe side the british gallon is different from the US gallon.
Re:more than just NASA in the history of space.... (Score:1)
> punds and so on.
And most importantly, PINTS!
Re:more than just NASA in the history of space.... (Score:2)
Ex: you can buy a pint of Guinness, or a
Maybe there were some Irishmen working on the conversion screwup?
We'll See... (Score:1)
Or, it will fire its 64.0-newton main engine for approximately 197 minutes to allow itself to slam into the surface at about 20x the speed of sound.
Decimals sure can be a bitch.
Forget the metrics... (Score:1)
Beware reduced visibility! (Score:2, Interesting)
Gamma Ray Vision. (Score:2)
Re:Beware reduced visibility! (Score:1)
At least now we know what went wrong the first try (Score:3, Funny)
with these kinds of drafting techniques...
.....And end up crashing... (Score:1)
Seriously, I hope the mission goes as planned, and doesn't circum to the problems that haved dogged missions to Mars in the past!
Tony
Looping orbits? (Score:2)
Re:Looping orbits? (Score:3, Informative)
All orbits (about a single body) are conic sections, not necessarily ellipses. Given just barely enough energy to escape the body results in a parabolic orbit, and having excess energy results in a hyperbolic one. If the orbit is 'captured,' it has an elliptical shape.
I agree though, that 'looping' and 'elliptical' shouldnt be used as synonyms.
Re:Looping orbits? (Score:2, Insightful)
Re:Looping orbits? (Score:1)
I always balk at unbound trajectories "orbits". It goes against my perceived meaning of the word, somehow.
Perhaps by "looping" the press release was refering to how the orbit won't be closed? Yeah, I doubt that they were being that subtle, too.
Re:Looping orbits? (Score:2)
Re:Looping orbits? (Score:3, Informative)
All orbits are elliptical, anyway.
Actually, orbits are only elliptical around isolated, spherically symmetric objects in Newtonian gravity. Planets are neither isolated, nor spherically symmetric, and gravity is not Newtonian :-) In the real universe, planets are approximately oblate spheroids with "small" surface ripples, like mountains, valleys, etc, which result in radial variations that make individual orbits look like "wavy ellipses" (which is actually a major source of systematic error in the GPS system that needs to be regularly corrected); further, the non-Newtonian nature of gravity (read General Relativity) causes orbits, even around perfectly symmetrical objects, to not close into ellipses, but to precess with time. And there are all sorts of other effects that you need to worry about (other planets, the sun, atmospheric drag, etc. etc. etc.) that further modify the orbit of spacecraft, guaranteeing that they're orbits won't actually look anything like ellipses on all but an "average basis" over a few orbital periods.
Hmm.. (Score:3)
All stable orbits are looping. Elliptical just means that it isn't always a uniform distance from the origin of the orbit, in this case, Mars.
Re:Hmm.. (Score:1)
...
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Re:Hmm.. (Score:1)
Also a circular orbit, would not be classified as an eliptic orbit (Although mathematically it can be described as an elipsis with the small axis equal to the long axis).
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Re:Hmm.. (Score:1)
Indeed - and even if it were a uniform distance from the surface, surface features not withstanding
Re:Hmm.. (Score:1)
Orbit (Score:4, Informative)
If all works well, that's what'll make this mission a success - the aerobraking technique means significantly lower fuel requirements, which makes for a lighter and thus less expensive mission.
Let's hope everything works right this time!
Re:Orbit--but what shape? (Score:2)
:)
hawk
Re:20 down to 2 = Slower? Confused (Score:2)
It has to do with kinetic and potential energy. For simplicity, assume circular orbits. The potential energy of an orbit is defined to be zero at an infinite orbital radius, and it becomes more negative as your radius shrinks.
Kinetic energy is positive, and is related to how fast you're going. For a circular orbit this turns out to be (IIRC) exactly -1/2 of the potential energy. So the total energy of an orbiting body is (KE + PE) = ((-1/2 * PE) + PE) = PE/2 (which is still a negative quantity).
Now when a body loses energy through aerobraking friction, its total energy decreases. This means that its potential energy decreases but its kinetic energy (therefore its speed) increases.
[Hope I got that right. It's been a while since I had to do this stuff]
Be careful (Score:1, Funny)
By flying all these spacecraft into Mars, we may be destroying their ecosystem, and future generations of Nartian aliens may well have an issue with us violating their airspace, and they may well retaliate, or at least prosecute. Perhaps we should ask before sending these probes
Re:Be careful (Score:5, Informative)
Actually, we don't, that's one of the things this probe has been sent to determine. There is an ambiguous but intriguing body of evidence that liquid water may once have flowed on Mars' surface, but what water remains is yet to be determined.
We have known for some considerable time that Mars has a very thin atmosphere composed primarily of carbon dioxide. It is less than 1% as thick as Earth's atmosphere.
Your chain of reasoning is getting increasingly tenuous.
Odyssey is an orbiter, not a lander. It will never come in contact with the planet. Even if the worst happens, like it did with Mars Climate Orbiter in 1999, the thin Martian atmosphere is still thick enough to ensure that nothing uncharred reaches the surface. All landers are thoroughly sterilized before leaving Earth.
Re:Be careful (Score:2, Interesting)
I do believe though that out of respect, we shouldn't litter the planet with all sorts of robots and stuff... If there is no other way though, then oh well.
Re:Be careful (Score:1)
remove that almost and your right. mercury has a tenuous atmosphere of hydrogen and helium that it keeps around itself. and pluto is showing great signs of having a nitrogen based atmosphere... although a very cold one.
Re:Be careful (Score:2)
And there might be liquid water on mars, under the surface that is. and liquid being about 0C in a slushy state.
Re:Be careful (Score:4, Funny)
Perhaps we've deduced the source of the original post?
Re:Be careful (Score:1)
We have known for some considerable time that Mars has a very thin atmosphere composed primarily of carbon dioxide. It is less than 1% as thick as Earth's atmosphere.
There is actually an even better example of the flaw in that log. Europa. Liquid ocean (probably) with 0 (zero) atmosphere. There is absolutely no requirement that a liquid water environment have an atmosphere. In Europa's case, the ice cap is preventing the lower ocean from freezing or boiling off.
Re:Be careful (Score:1)
Lucky there are others who know otherwise.
Re:Be careful (Score:1)
Actually, we don't, that's one of the things this probe has been sent to determine
Actually we do know that there is water on mars, as is evident from watching the polar caps form during the winter season on the planet. The problem is that these caps are very very thin and aren't liquid, so they wouldn't provide for a lot of water on a sustainable basis (These caps come from the water vapour (0.03%) that is in the atmosphere). What they're looking for is a large well of liquid water that can be readily tapped and used.
We also know that there is fungal blooms that happen, so there is at least a basic rudimentary "life" "ecosystem" on the planet, however there is no sign of any sort of animal life.
Re:Be careful (Score:1)
Say what? There are no fungal blooms on Mars. There is no evidence for any life whatsoever on Mars.
Re:Be careful (Score:2)
There is a pronounced darkening of many surfaces on Mars during the summer months, and I had read somewhere that it was due to some sort of fungus, however thinking about it that is pretty much absurd, and I can't seem to find the story that I had read before to support that.
Re:Be careful (Score:1)
Umm... No.
The martian 'ice' caps are CO2 ice, not water ice.
Re:Be careful (Score:1)
About the dust storm (Score:2, Informative)
Re:About the dust storm (Score:1)
Who cares about water ??? (Score:1)
Land a fscking probe there and tell me if there's life or not.
Damn it, man. US send a bunch of probes to mars in the 70's, with computers 1000 less powerfull than a PS2. why we can't do it again now ???
Re:Who cares about water ??? (Score:2)
Life cares about water (Score:2, Informative)
Learning where the water is is a necessary prerequisite to finding what life may still exist. If there is life still there, it will be close to water. Water is easier to find that scant traces of life. Therefore, find the H2O, and you actually have a chance of finding something else.
NASA sent only two probes to Mars in the 70's, Viking 1 & 2. It has firm plans to send at least one probe every two years until at least the end of the decade. Considering the budget they operate within, I think they're doing a damn good job.
Re:Life cares about water (Score:1)
Minor point, I know.
Re:Life cares about water (Score:1)
Learning where the water is is a necessary prerequisite to finding what life may still exist. If there is life still there, it will be close to water.
What makes you think that? Why does everyone see to think they know what "life" is? Such statements remind me of early speculation that Mars or even Venus could be "sister planets" to Earth that humans could live on if we could just reach them. Then we discovered that their atmospheres are, uh, less than hospitable. To believe that all life requires water is equally foolish. In fact, I'd say that when it comes to alien life and alien intelligence, it will be so alien when we first get exposed to it that we won't recognize it as either for the most part.
Re:Life cares about water (Score:2, Interesting)
Well, several things would seem to point to that being the most likely course of events if there is any life on Mars at all.
First and foremost, remember the Martian meteorite that reignited the whole debate? Some scientists are now theorizing that life was thrown about amongst most of the bodies of the inner Solar System in the early days. Therefore any life that did take root on any planets would have features in common. Life on Earth is water based, so any Martian life is therfore more likely to be the same.
Centuries ago, people thought the planets were gods. At least the more recent idea of sister planets was closer to the truth. Theories are continuing to evolve, and much current speculation will turn out to be wrong, but we know more that we used to.
It's impossible to eliminate really exotic biochemistries, but in the inner Solar System water-based life has an overwhelming advantage for many of the same reasons that life is also carbon based: those chemicals are unbelievably versatile, far more so than any other form of chemistry. Liquid water has a number of properties that set it apart from other substances. Ask any chemist about hydrogen bonding and thermal properties. It makes water possibly uniquely suited to its role in life. Any alternate biology would seem unlikely within the so-called "habitable zone" around the Sun.
Infamous Martian defence force (Score:2)
Don't forget about the infamous Martian Defence Force. [8k.com] These guys are sure be up for some more target practice.
Re:Infamous Martian defence force (Score:2)
The Role of Earth [xenu.net]
Re:Who cares about water ??? (Score:2)
Totally.
Re:Who cares about water ??? (Score:2)
C'mon, we land a probe on Mars every year or so. Only problem is, if there's life on Mars, any life around the vicinity of our landing sites is vaporized or crushed by our landing technique.
("Oh, you mean you wanted the probe to be functional after it lands. Sorry, that'll cost extra! And one guy forgot to specify whether he wanted his probe in solid, liquid, or gaseous form upon landing. He was on a budget, so we went with gaseous.")
orbit about 20 hours long? (Score:1)
Far out (literaly!) (Score:5, Insightful)
Since space radiation presents an extreme hazard to crews of interplanetary missions, the experiment will attempt to predict anticipated radiation doses that would be experienced by future astronauts and help determine possible effects of Martian radiation on human
You have to give NASA credit for thinking far ahead. I'm not that optimistic about space exploration. We need some major breaktroughs in order to get further away from the moon.
First theres the problem with the propulsion system: we're simply not fast enough in our spaceships. In order to get anywhere we need to approach the speed of light or even exceed it (or better yet, make the whole thing about space/time irrelevant, but that is sci-fi for the time being)
Second humans are really not meant to be put in space. We need to adapt, and we need to adapt in a serious way. Most of our body is made up of this little molecule H2O, and we need lots of it to survive. Water is not easy to get in space! Food is another problem. Another is that the human bonestructure degenerates in space (it wouldn't be smart spending billions on spaceexploration just to make astronauts land on mars realizing that they have become crippled in the meantime. We can minimize the effect of zero gravity but the problem remains.
I dream of space too (wonder if all people does in a way). Just can't see how we're going to get there. What bothers me the most are that I don't find much evidence either, of breakthrough technologies that will make humans able to explore space by them self in my lifetime. Pitty really, it's just not the same wathing a robot land somewhere doing the exploration for us! (well maybe for the guy controlling the robot
Re:Far out (literaly!) (Score:2, Informative)
In order to get anywhere we need to approach the speed of light or even exceed it (or better yet, make the whole thing about space/time irrelevant, but that is sci-fi for the time being)
You ain't just whistling Dixie when you say it's science fiction. The fastest propulsion system proposed that we're fairly sure would work is Orion, which uses a chain of mini atomic bombs to get to 10% of c. Don't even think about trying to build it with todays technology. Anything else is currently just fantasy.
We don't need to get close to the speed of light for travel within the inner Solar System. If NASA felt that public opinion would tolerate it, they could use nuclear rockets, in which an atomic reactor was used to accelerate the fuel. That is the technology, which we could start building today, that will make travel to and from Mars feasible. We are not, in my opinion, going to get to Mars with conventional rockets.
Re:Far out (literaly!) (Score:1)
This is very hard. Weird sh*t happens when you try that. You get heavier, shorter and time slows down. IANAP (I am not a Physicist) but we aren't going to get close to the speed of light until we radically change our physics (read: find a loop hole in Relativity eg. worm holes etc).
If a physicist out there is planning on the whole "But it's impossible!" rant, skip it. We WILL find a way. I know that it can't be compared to breaking the speed of sound but you can't say it is impossible until you're sure that you know every bit of Physics there is to be learned.
Impossible is a word that shouldn't be used alone. Impossible with our current knowledge is more appropriate, and it stops you looking like a fool later.
No flying attack porcupines required. (Score:2)
Actually, we could do it now. It would just be horrifically expensive.
Method number one is to use an external power source to accelerate the ship. The least expensive way to do this is to build a giant laser array in space and use this to propel a solar sail. This would still take something like the US's entire military budget for the last century to implement (out of our price range for now).
Method number two is to use a fuel with a very high energy density, with a nearly-perfect drive. Antimatter works decently for this (antiproton annihilation produces charged particles (mesons) that can be directed with a magnetic field before they decay). However, the entire world production of antiprotons is something like a few nanograms per year. A pure-antimatter-drive ship would need hundreds of tonnes. Other approaches to interstellar craft use various types of fusion drive. The problem is that you need a fusion reaction that leaves most of its energy as kinetic energy of charged particles, which rules out the easiest two or three forms of fusion (which aren't terribly "easy" to produce as it is).
So, we could build an interstellar near-C laser launched sailcraft now, for an insane amount of money, and we'll probably be able to build interstellar-capable fusion craft within the next hundred years or so. Both methods are difficult, but neither is impossible and neither requires new physics.
If a physicist out there is planning on the whole "But it's impossible!" rant, skip it. We WILL find a way.
The universe has its own idea of what its laws are, and doesn't care how much we *want* to find a way. Hard limits exist.
Problems are less severe than you paint them. (Score:5, Informative)
Getting to another star system would require near-C travel, but getting to other planets certainly doesn't. Chemical rockets can get just about anywhere in the inner solar system in a couple of years, and anywhere in the outer solar system within about five years.
Use an ion drive, and you can get just about anywhere within 1-2 years.
Sure, you won't be commuting to Mars for the weekend, but this is certainly good enough for colonization and trade. Think back to the old days of wooden ships on Earth.
Second humans are really not meant to be put in space. We need to adapt, and we need to adapt in a serious way. Most of our body is made up of this little molecule H2O, and we need lots of it to survive. Water is not easy to get in space! Food is another problem. Another is that the human bonestructure degenerates in space.
Humans aren't going to change their basic structure. We can, however, build contained environments that can support us.
Water isn't a problem. We already have water-reclamation systems that are perfectly efficient (we just don't use them because they're expensive). Your ship is air- and water-tight - you won't lose any mass to space.
If you have a big enough ship, food isn't a problem - grow it the old-fashioned way. Or stockpile a year's worth of army rations (this will take mass, but not an unmanageable amount of mass; it's just probably cheaper to grow food).
Gravity similarly isn't a problem. You can either live with bone degeneration, or you can connect two ship parts with a long cable and spin them to get a wonderful simulation of gravity and avoid all zero-g related health problems.
In summary, I don't think we need any new magical technology for in-system space travel. We have pretty much everything we need already.
Re:Far out (literaly!) (Score:1)
food?? hmmm, dunno, grow plants purhaps?
so, sorted!! piece of cake!!
sh*t happens (Score:1, Funny)
Re:sh*t happens (Score:2)
Go Mars!? (Score:1)
Ah, I remember the long nights of SimEarth, working to terraform Mars into a habitable environment with carbon dioxide and water vapor generators... then getting bored and flinging a couple of ice comets at it -- accompanied by the terrible Sound Blaster MIDI sound FX -- and then finally overdoing it and creating a planetwide ocean. I wonder what approach NASA is planning to take?
Too bad that game didn't have an option to make sentient rocks...
Re:Go Mars!? (Score:2)
-l
What it's doing there (Score:5, Informative)
High Res Spectrometers
This baby has two spectrometers, one in infrared for working out the mineral composition of the surface to a resolution of 100 metres [nasa.gov], and one in gamma rays, for working out how much hydrogen there is near the surface [nasa.gov], and consequently how much rocket fuel they can make in different places if/when they land.
Comms satellite It acts as a relay between the surface and the Earth, so any new probes (like the twin rovers due to take off next year) wont have to carry big dishes and radios.
All this and more on the website [nasa.gov].
Are you sure it's 640 Newtons (Score:1)
Re: (Score:1)
Re:fun (Score:1)
Dust Storm (Score:3, Interesting)
A great article on the whole procedure is at this link [nasa.gov].
Re:Dust Storm (Score:1)
Amazing though that with computers and robotics, a lot of these are being automated so that mission controllers only need to make small changes.
Since you're going to site... (Score:2, Informative)
specially the mars global surveior's one, with cool hi-res pics of the "martian face". the link is here:
http://mars.jpl.nasa.gov/mgs/msss/camera/images/m
Careful Nasy (Score:1)
Did he crash it?
</jarjar>
What's the point? (Score:2, Redundant)
Dust storm question (Score:1)
Universal Time? (Score:2)
Space (Score:1)
40 bits per second (Score:1)
Set up mirrors! (Score:1, Flamebait)
The doppler plot is the main thing that everyone will be looking at, and I bet it's going to be completely unavailable during the most interesting times.
How about a few dozen mirrors to help NASA out?
Re:Set up mirrors! (Score:2)
I am serious. NASA's webservers will NOT be able to keep up with the load, and the doppler plot will NOT be available to look at while the thing is entering orbit.
So, I post it again. Will some people set up some mirrors of the doppler plot to take the load off NASA's servers just a bit?
We get signal. (Score:2)
Re:Truly amazing ! (Score:4, Insightful)
We will know more. That's how.
Knowledge is the only thing that truly separates us from barbarism and animals.
Re:Truly amazing ! (Score:2)
How does that make us better off? Because we can do it. Because we can habitate other planets and expand our race beyond just one planet.
And because we can.
Re:Truly amazing ! (Score:3, Insightful)
Two examples should suffice to prove my point.
With regard to technology, the integrated circuit was developed for NASA, to use in satellites and spacecraft. No doubt, if the space program had not existed, the IC would have been invented some time or other; but the space program meant that we had it sooner and faster than we would have had otherwise. Big, interesting problems bring about technologies that are interesting and useful; and no problem is bigger or more interesting than space flight.
With regard to the spiritual value, think of the photograph of the Earth rising over the Moon that Anders took in Apollo 8, in 1968. Can you think of a better description of the unity of the Earth, and its relation to the cosmos? I think that photo alone was worth the billions we spent on the space program.
Recently, I viewed the movie "Apollo 13" with my two teen-aged children. It's quite a movie, for it captures the excitement - the romance, if you will - of the Apollo adventure. The hardest part was trying to explain to the kids why it was that when I was their age, we were flying men to the Moon, but nowadays we have simply given up going.
When I look around the world now, with the horror of 911, and of the Afghanistan war, and the rise of Islamo-Fascism threatening to return the world to the dark ages, we need to remember the glories of enterprises like the the exploration of space, which enriched the lives and broadened the imagination of all humankind.
Re:Pre-Arrival News Conference (Score:1)
Re:Hmmm, wait! It's closer to Jupiter! (Score:1)