How does gravity assist with interplanetary satellites?

work with interplanetary satellites? When NASA sends satellites out to the outer reaches of the Solar System, it will often send the satellites past the planet for a gravity assist. The satellite speeds up in the process. The idea behind a gravity assist is to use the planet's motion to accelerate the satellite. For example, as satellite heads towards Jupiter in the process, it accelerates because it's falling towards Jupiter through Jupiter's gravity. Then it passes fairly close to the

planet and starts speeding away from it. However, at that point, the satellites starts slowing down because gravity is pulling it back towards the planet. From that description, it would seem like the net effect of gravity assist is zero. The satellite gains speed as it falls towards the planet, but then it loses it as it heads away. The thing that makes the assist work is the fact that the

planet is in motion in its orbit. Jupiter, for example, is about five hundred million miles away from the Sun, which means that the circumference of its orbit is about three billion miles. Jupiter travels that distance in about twelve years, so it's moving through space at about thirty thousand miles per hour. If the satellite is moving in the same direction as Jupiter in its orbit, then it can actually increase its speed by thirty thousand miles per hour. That's

a huge speed increase, and it's completely free. The problem with the assist is that you have to wait for the planets to line up correctly for it to work. That's why missions have to fly within certain time windows. For more on this and thousands of other topics, is it How stuff works dot Com Protect your photos, music and documents and access to them anywhere with mosey by e m C the most trusted name and cloud backup and now save ten with promo code. Brain Stuff at

mosey dot com. Get started today at m o z y dot com