why spammers don't have a return email address, don't have a url to visit and don't have a phone number. I can understand spammers trying to generate business, but when there is no easily discernable way to contact them OR any business, what's the point.
That is true, especially at the unstable Lagrange points, but the simple solution to that is to do a long burn with the maneuvering jets. If you did a very short duration high intensity burn, then you could easily go flying very far off course. But by doing a low powered long lasting burn to correct the course, the error is very small.
It does apply to everything, but the little bit that is applies to really big things like planets and their effect on a space craft is negligile.
SLING SHOT...
A lot of people are talking about using gravity to propel a space craft, but don't seem to understand exactly how it works. When a space craft sling shots around a planet, what happens is this. The SC is captured by the gravity of the planet. The SC begins to fall towards the planet. However, it is falling at such an angle that it will never hit the planet or a significant portion of its atmosphere and is therefore release back into space. Now, conservation of energy applies and says that the kenetic energy gained by falling towards the planet is lost when it escapes on the other side. BUT (this is the heart of how the sling shot works) the planet is orbiting the sun. When the SC begins falling towards the planet, it also gains some of the energy from the planet itself. The SC picks up a significant portion of the velocity of the planet in it's orbit around the sun. When you apply the law of gravity for 2 bodies, you will figure out that the planet actually slows down because some of its energy is given to the SC. The end result is a SC that is going much faster and it didn't have to burn any fuel.
SPACE CRAFT'S FUEL...
several people are saying that the SC doesn't need to use fuel. If we could calculate exactly where everything is in the universe, then we could do it with almost no fuel. But we can't. Also, as all the calculations are only a pretty good estimate, the SC carries enough fuel to make in flight corrections.
LAGRANGE POINTS...
There are 5 points where gravity cancels exactly.
1. directly between the earth and the moon.
2. leading both the earth and the moon. It is in orbit around both the earth and moon, but does not move realtive to them because it can't fall around both.
3. same as 2, but trailing instead of leading
4. on the opposite side of the earth from the moon
5. on the opposite of the moon from the earth.
HOWEVER, only 2 points are STABLE. Points 1,4 and 5 are unstable, points 2 and 3 are stable. If you solve the problem, you realize that points 1,4, and 5 are sources and points 2 and 3 are sinks.
Now to qualify myself. I've only had 2 astro engineering courses (taken for fun) a few years ago back in college, so if i've made any mistakes, please forgive me and correct me.
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But if I can't find any way to respond (not like i would even if i could), then how does that make them any money?
why spammers don't have a return email address, don't have a url to visit and don't have a phone number. I can understand spammers trying to generate business, but when there is no easily discernable way to contact them OR any business, what's the point.
That is true, especially at the unstable Lagrange points, but the simple solution to that is to do a long burn with the maneuvering jets. If you did a very short duration high intensity burn, then you could easily go flying very far off course. But by doing a low powered long lasting burn to correct the course, the error is very small.
CHAOS THEORY...
It does apply to everything, but the little bit that is applies to really big things like planets and their effect on a space craft is negligile.
SLING SHOT...
A lot of people are talking about using gravity to propel a space craft, but don't seem to understand exactly how it works. When a space craft sling shots around a planet, what happens is this. The SC is captured by the gravity of the planet. The SC begins to fall towards the planet. However, it is falling at such an angle that it will never hit the planet or a significant portion of its atmosphere and is therefore release back into space. Now, conservation of energy applies and says that the kenetic energy gained by falling towards the planet is lost when it escapes on the other side. BUT (this is the heart of how the sling shot works) the planet is orbiting the sun. When the SC begins falling towards the planet, it also gains some of the energy from the planet itself. The SC picks up a significant portion of the velocity of the planet in it's orbit around the sun. When you apply the law of gravity for 2 bodies, you will figure out that the planet actually slows down because some of its energy is given to the SC. The end result is a SC that is going much faster and it didn't have to burn any fuel.
SPACE CRAFT'S FUEL...
several people are saying that the SC doesn't need to use fuel. If we could calculate exactly where everything is in the universe, then we could do it with almost no fuel. But we can't. Also, as all the calculations are only a pretty good estimate, the SC carries enough fuel to make in flight corrections.
LAGRANGE POINTS...
There are 5 points where gravity cancels exactly.
1. directly between the earth and the moon.
2. leading both the earth and the moon. It is in orbit around both the earth and moon, but does not move realtive to them because it can't fall around both.
3. same as 2, but trailing instead of leading
4. on the opposite side of the earth from the moon
5. on the opposite of the moon from the earth.
HOWEVER, only 2 points are STABLE. Points 1,4 and 5 are unstable, points 2 and 3 are stable. If you solve the problem, you realize that points 1,4, and 5 are sources and points 2 and 3 are sinks.
Now to qualify myself. I've only had 2 astro engineering courses (taken for fun) a few years ago back in college, so if i've made any mistakes, please forgive me and correct me.