The moon is always falling toward the Earth. Why doesn't the moon "hit" the Earth?

Answer 1

No,it isn't.the Moon is moving away at 4,5 cm a year.

Answer 2

The best way to picture this is to visualize the moon moving through space in a straight line past the earth. It is moving "sideways", relative to the earth, but also "away", after it passes it's closest point. That would be all that would happen if there were no gravity. There is gravity though, and it causes the moon to "fall" toward the earth at a velocity determined by their masses and the distance between them. When the rate the moon moves "away" equals the rate it "falls", it finds itself travelling in a circular (actually elliptical) path around the earth. That is when it is said to be in "orbit". If these forces were in perfect balance, the situation would remain unchanged forever. Nothing is perfect though, and the moon moves a little farther away every year. I thought that was about 3.8 cm/year, but someone said 4.5 and they're probably more current than I am. The rate of recession was first measured by instruments used by the Apollo Astronauts (of course), but has since been refined to greater precision by many other methods that weren't available then. The fact the moon is moving away was discovered 30 years before Apollo by a scientist who measured tides for the Navy. It had been impossible to determine the actual rate of recession until the Astronauts placed their instruments as needed for the experiment.

Answer 3

Think about it. If you throw a rock, it orbits the Earth for a bit, then slams into the ground. The harder you throw it, the farther it'll go, but it always hits the ground. If you could throw it as fast as a satellite travels in low Earth orbit (about 17,500MPH), it would (provided it had enough altitude) go AROUND the Earth, WITHOUT hitting the ground. The key to this is, the Earth is only 8,000 miles in diameter. If it were, say, 8 inches in diameter, (with the same mass) and you threw a rock, the rock would still orbit the Earth, but now it would *miss* the surface.

Same with the moon. It's falling to Earth, but the Earth's surface curves away, allowing the moon to continue in it's orbit.

Answer 4

The moon's acceleration (the falling you refer to) caused by Earth's gravitational field remains almost exactly perpendicular to it's direction of travel at all times maintaining the Moon's nearly circular path.

The analogy of swinging a weight by a string on a circular path is a good one... You provide the weight a constant acceleration perpendicular to its motion (centripetal acceleration) ...Its speed remains roughly constant while its *velocity* changes.

It is worthwhile to remember that there is nothing special about an orbit as opposed to, say, the trajectory a stone takes when you throw it in the air...the stone's trajectory just happens to intersect the Earth's surface.

Answer 5

Because it has a forward motion (velocity) perpendicular to the distance from the center of mass of the earth to the moon's center of mass. Similar to a ball on the end of a string being twirled around your head at constant speed. The ball is accelerating inward toward your head (centripetal acceleration) but it never hits your head because it is speeding around your head with a velocity perpendicular to the string. The CHANGE in velocity is directed toward your head (the same direction as the force holding the ball in its circular path). That's the direction of the acceleration. Towards your head. The same analysis applies to the moon falling towards earth, except gravity is the force not the string.

Answer 6

The moon travels so fast around the earth that it doesn't collide with the earth. Over the years, the moon is traveling farther away from the earth.

Answer 7

The moon is traveling away due to the fact that the moon has an elliptical orbit.When the moon was first formed,it was only 15,000 miles away,compared to about 220,000 miles now.

Answer 8

As it falls it is really revolving around the Earth. It is not really falling, but is just being pulled toward the Earth. However, it's own forward momentum plus this gravitational pull cause it to revolve around Earth without really moving out of its orbit.

Answer 9

the moon is going faster then it fall it is like when you trowing a rock long as it can keep the speed it will flysoon as the speed fall the rock will do the same

Answer 10

It is moving sideways fast enough to keep missing Earth to one side.