How does the space ship have enough fuel to get to Pluto?
Does it just coast or does its boosters give it constant thrust? How could they fit so much fuel on the little ship?
Does it just coast or does its boosters give it constant thrust? How could they fit so much fuel on the little ship?
Anonymous
Don't you know? It has an electric extension cord that goes all the way back to Cape Canaveral.
No, actually, in addition to coasting most of the way (once it got up to speed), it's electronic functions are maintained by a small nuclear
battery on board, good for years. This also provides heat to keep the electronics from freezing, and is the only source of real heat for billions of miles (it's 400 below zero F, out there). Voyagers 1 &2, both launched in the 70's, are still running on nuclear batteries.
And, it has enough hydrazine, rocket fuel, on board for occasional course corrections. It's mission is not over- it will continue to explore the Kuyper Belt. Even the Voyagers are
still able to maneuver using rocket fuel loaded almost 40 years ago.
Raymond
It coasted all the way, slowing down as it "climbed" away from the Sun. Most of its speed was given as an initial impulse when it left Earth. It was then already going faster than Solar Escape speed (meaning = it will never stop and fall back towards us).
Almost all the fuel was in the rocket that gave it its initial boost. After that, very little fuel was kept for course correction (not for acceleration).
There was a contribution from Jupiter through the "slingshot effect".
Although it has been slowing down for nine years (except for the few days around Jupiter) - because of the Sun's gravity -- it is still going ten times faster than the fastest bullet from a rifle.
?
For most of the way, yes, it just coasted. Think of Newton's first law of motion - any body will remain at rest or continue in a straight line unless a force acts on it. So all you need to do is launch it with a big rocket so it gets up to a high speed to start with, point it in the right direction, and just let it go. It's a little more complex than that - it was directed around Jupiter to get a boost from the slingshot effect of Jupiter's gravity - but that's basically it with any space probe. If it turns out to be heading off course, it only needs a little nudge to correct course - and it has little rockets for that.
Let's say you fired a gun in space. The bullet would just keep going forever unless it hits something, because there is no force to slow it down.
The key thing is to get it going fast enough to escape Earth's gravity, and then it will just keep going because there's no friction in space. Once it's going, you don't need fuel. If you let a car coast, it will slow down and stop, but that's because there is a force acting on it - friction between the wheels and the road. A spaceship isn't running on a road, there's no force like that to stop it, so it just goes on and on and on. Same reason planets etc continue in orbit without being powered - did you think of that one :)
New Horizons was given the fastest initial velocity of any space probe ever just so it could get to Pluto within a reasonable time (like before all the scientists who worked on it have retired!) but yes, after it got speed, it just coasted. If you keep boosting it, it'll just go faster all the time, and that's what you DON'T want or it would have shot past Pluto too fast to take any pictures. What couldn't be done was to make it slow down to stay at Pluto longer, because that WOULD have meant carrying more fuel and rockets to slow it down by firing them in the opposite direction.
?
Others have already explained it pretty well. It was launched at a very high velocity, faster than any other spacecraft ever launched from earth. The launch vehicle used was an Atlas 5 551, the second largest launcher currently in the U.S. inventory, and it is a relatively small spacecraft, about 1,000 pounds. In addition, it flew by Jupiter for a gravity boost, a procedure used on many space missions. Other than during launch, the Jupiter flyby, and relatively brief course corrections, it coasted.
quantumclaustrophobe
The initial boost was given here at Earth, to leave Earth orbit (the fastest of any probe in history).... from there, it was simply a few course corrections out to Jupiter; Jupiter's gravity and motion gave it a speed-assist, boosting it a bit and altering it's course to intercept Pluto. The only fuel it needs is attitude correction and small amounts to adust it's course slightly...