Established Member
I just saw the trailer...looks like we have another unbelievably dense asteroid belt popping up in this one.
If the odds against successfully navigating an asteroid belt are really that bad, shouldn't we have lost at least one of our spacecraft going to Jupiter, Saturn, or beyond when they passed through it?
Rob
Established Member
Not to argue the odds, but haven't most of our craft going beyond the Asteroid Belt gone out of the ecliptic and over/under the Belt rather than "through" it? I can't recall any actual foundation for that, but I seem to remember that being discussed for at least some of them, simply due to the fact that the odds, while smaller than Hollywood would have us think, aren't quite small enough to risk billion-dollar projects on. At least, not to the comfort level of the people providing the billions of dollars (i.e., Congress).On 2001-11-03 23:36, Hale_Bopp wrote:
I just saw the trailer...looks like we have another unbelievably dense asteroid belt popping up in this one.
If the odds against successfully navigating an asteroid belt are really that bad, shouldn't we have lost at least one of our spacecraft going to Jupiter, Saturn, or beyond when they passed through it?
Rob
The (my belt's too large to go around, these days) Curtmudgeon
Order of Kilopi
Well, I don't have a cite, but my gut feeling is that the deep space missions go right through the asteroid belt, not "over it" or "under it". The energy requirements to push the spacecraft back "down" into the ecliptic seem prohibitive to me. But I could be wrong.
I vaguely recall this question being answered in a past issue of "Planetary Report", but I don't keep my back issues... doh!
Established Member
Keep in mind that I know nothing about orbital mechanics (can't even get past high school math) but I don't believe it would take any energy at all. You could do a 'slingshot' around the Sun in such a way as to put the spacecraft in what would essentially be a highly elliptical orbit at right angles to the ecliptic, and aim for Jupiter so that you can use its gravity well to straighten things out again.The energy requirements to push the spacecraft back "down" into the ecliptic seem prohibitive to me. But I could be wrong.
Do I get a gold star Phil, or did I mess up real bad?
Order of Kilopi
I agree that you could launch the spacecraft on a trajectory that puts it above the ecliptic with no penalty. But somewhere along the way, you have to push it back down, or else it's gonna fly way, way "north" or "south" of Jupiter. Or any other planet, except maybe Pluto.
You have to cancel out the vector that pushed you above the plane originally, and then provide even more push to get back down to the ecliptic by the time you get to Jupe. Of course, you have a long coast to do it in, so maybe you can afford that much fuel.
However, I do believe that the asteroid belt is so thinly populated that it's not a particularly high risk to go right through. After all, the rings of Saturn are much denser than the belt, and we've sent spacecraft right through them.
Established Member
No, you don't launch it on a trajectory that puts it above the ecliptic, well not by much anyway. You launch it toward the Sun so that it goes over the top or under the bottom, swings around in a veeeeeery long ellipse, intercepts Jupiter, and gets flattened out. In other words you arrange things so that the elliptical orbit around the Sun has Jupiter at or near its other focus.On 2001-11-04 15:01, Donnie B. wrote:
I agree that you could launch the spacecraft on a trajectory that puts it above the ecliptic with no penalty. But somewhere along the way, you have to push it back down, or else it's gonna fly way, way "north" or "south" of Jupiter. Or any other planet, except maybe Pluto.
You have to cancel out the vector that pushed you above the plane originally, and then provide even more push to get back down to the ecliptic by the time you get to Jupe. Of course, you have a long coast to do it in, so maybe you can afford that much fuel.
Maybe we can get Phil to make a diagram if I'm right, that would show what I mean a lot easier.
C'mon Phil, please please pleeeeease, can I get a gold star?!
Established Member
A lot of the recent probes to the outer planets used multiple gravity assists from Earth and Venus. I believe the Galieleo probe to Jupiter got one gravity boost from Venus and two from Earth (or am I mixed up with the Cassini probe to Saturn?) Anyway, using those types of gravity assists doesn't sound like it is going to be passing significantly above or below the asteroid belt!
I believe it is the Ulyesses satellite that was put into a polar orbit around the Sun by using Jupiter's gravitational field. It would be hard to do something like that using the smaller gravitational fields of the small inner planets.
I think we have sent most of these craft pretty much smack through the asteroid belt and haven't lost one...at least to asteroids!
Rob
Rob
Order of Kilopi
Correct, and the orbit was in (or very close to) the ecliptic until twisted almost 90 degrees by the slingshot around Jupiter.I believe it is the Ulyesses satellite that was put into a polar orbit around the Sun by using Jupiter's gravitational field.
Order of Kilopi
Hmmm... what you suggest sounds feasible, anyhow, if tricky. Still, they've done some mighty impressive navigation out there. All I can say is, I've never heard of such a trajectory before. If it's been used, they've been careful not to let me in on the secret! [img]/phpBB/images/smiles/icon_biggrin.gif[/img]On 2001-11-04 16:33, The Rat wrote:
No, you don't launch it on a trajectory that puts it above the ecliptic, well not by much anyway. You launch it toward the Sun so that it goes over the top or under the bottom, swings around in a veeeeeery long ellipse, intercepts Jupiter, and gets flattened out. In other words you arrange things so that the elliptical orbit around the Sun has Jupiter at or near its other focus.On 2001-11-04 15:01, Donnie B. wrote:
I agree that you could launch the spacecraft on a trajectory that puts it above the ecliptic with no penalty. But somewhere along the way, you have to push it back down, or else it's gonna fly way, way "north" or "south" of Jupiter. Or any other planet, except maybe Pluto.
You have to cancel out the vector that pushed you above the plane originally, and then provide even more push to get back down to the ecliptic by the time you get to Jupe. Of course, you have a long coast to do it in, so maybe you can afford that much fuel.
Maybe we can get Phil to make a diagram if I'm right, that would show what I mean a lot easier.
C'mon Phil, please please pleeeeease, can I get a gold star?!
Established Member
From what I remember, we sent them straight through the asteroid belt with no ill effects. Also from what I remember, the average distance between the asteroids is millions of kilometers.
Unfortunately, I don't recall where I saw either of the above statements, so either (or both) can be completely wrong.
But this much, I do know: a "Star Wars" style asteroid belt would collapse under its own gravitation in short order, unless the asteroids were formed by intense tidal forces, which would tear apart any sizeable planetoid before it could form.
But hey... it's special effects. It's more important than reality. [img]/phpBB/images/smiles/icon_biggrin.gif[/img]
Vulcan Administrator
All of these are very much in the ecliptic (though if you look closely you can see Ulysses looping up out of the ecliptic):
Image of Voyager (and other spacecraft) paths through the solar system
Vulcan Administrator
I wanted to add that I learned in my orbital dynamics class that plane changes to an orbit are very, very expensive, which explains why Ulysses had to go out to Jupiter before it could go over the Sun's poles.
Established Member
"SNIP"On 2001-11-04 12:51, The Curtmudgeon wrote:
Not to argue the odds, but haven't most of our craft going beyond the Asteroid Belt gone out of the ecliptic and over/under the Belt rather than "through" it? I can't recall any actual foundation for that, but I seem to remember that being discussed for at least some of them,On 2001-11-03 23:36, Hale_Bopp wrote:
I just saw the trailer...looks like we have another unbelievably dense asteroid belt popping up in this one.
If the odds against successfully navigating an asteroid belt are really that bad, shouldn't we have lost at least one of our spacecraft going to Jupiter, Saturn, or beyond when they passed through it?
Rob
Russ Replies: I know the answer to this!!! (for once) [img]/phpBB/images/smiles/icon_redface.gif[/img]. They go "straight" through. Actually arc through but that's being nit picking. Just about all of the probes that have passed Mars for the outer planets have taken pictures of the astroids that they passed on the way. I know the Voyagers got rather fuzzy/blocky shots of some. Both Galleio and Casini got great shots. If memory serves, both Gal and Cas were specifically vectored to pass within range of specific astroids.
Established Member
Okay so...
If I had a Millenium Falcon and wanted to show off my elite piloting skills to impress people, and maybe smuggle some stuff aboard at the same time, where would I go to find a dense asteroid field, such as the one we see in the Empire Strikes Back? Saturn's rings?
I'd think it would be orbiting Earth in a few years, among space junk, but that's just me. [img]/phpBB/images/smiles/icon_biggrin.gif[/img]
Still, that would be one hell of a ride, wouldn't it? [img]/phpBB/images/smiles/icon_biggrin.gif[/img]
Established Member
{Sigh} It seems that I am again called upon to defend Star Wars.
One, it's not the asteroid belt in the Sol system. So we shouldn't be saying that it should act like the asteriod belt in the Sol system.
Two, we don't know what the system mechanics are like. It is very possibile that the system does work in a way to allow dense asteroid belts/fields
Three, IT'S A FRIGGIN' SPACE OPERA. People fight with swords made of energy! People have microscopic life forms in thier system that allow them to effect matter and energy at a distance, warp time, and predict the future accuratly! THERE IS SOUND IN SPACE BECAUSE ITS JUST PLAIN COOL!!!
C'mon, I'm as big of a geek as everyone here (I'm just a database geek instead of an astronomy geek), but this is pushing it, even for us. To quote Robin Williams "YOU'VE DONE IT NOW! YOU'VE GONE TO FAAAAAAAR"
{Carl pants while he tries to catch his breath. He looks down and noticed he's on the %$^# soapbox again. He shrugs and steps down and walks off}
Newbie
It's possible that the "asteroid belt" in the trailer is really debris from a destroyed planet or moon. Perhaps a proto-Death Star device was used. We'll find out this summer.
-Mike
Established Member
I remember in some of the books there is a smuggler's base deep inside an asteroid field (I forget what it was called now, but it was featured in several of the stories). The approach was supposed to be very dangerous, which was one reason they were hidden there. I wonder if that could have anything to do with this movie?
In any case, it seems that the physics of the Star Wars galaxy is slightly different from our own.
PS: Does anyone know a website where we can download or see this trailer? Some of us don't get to the theater very often. [img]/phpBB/images/smiles/icon_smile.gif[/img]
Established Member
The trailer is at www.starwars.com which I wouldn't suggest since it was VERY slow to me. It's also on www.apple.com which happened to be a lot faster.
I now know why it is called the "Breathing" trailer. [img]/phpBB/images/smiles/icon_smile.gif[/img]
Enjoy!
Established Member
Space probes are sent straight through the asteroid belt. There is nothing there. It's plain empty space with a few rocks every few hundred thousand kilometers.
Member
Star Wars takes place a long time ago in a place very far away, therefor the asteroid field is not the one in our solar system. As someone else pointed out, this field could be the product of a recently destroyed planet or moon.
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