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The more massive a planet or star is, the stronger the gravitational force it exerts. It is this force that allows a planet or star to hold other objects in their orbit. This is summed up in Isaac Newton's Universal Law of Gravitation, which is an equation for calculating the force of gravity.

Newton's Universal Law of Gravitation is a formula for understanding the relationship of gravity between two objects. The equation is "F = G(M1)(M2)/R," where "F" is the force of gravity, "G" is the gravitational constant, the "M"s are the masses of the objects being considered, and "R" is the radius of the distance between the two objects. Thus, the more massive either object is, and the closer they are together, the stronger the force of gravity.

Gravity is what keeps planets in orbit around the sun. The sun is extremely massive, thus it holds very distant objects, like the outer planets and comets, in its orbit. This can also be seen on a smaller scale, with planets keeping satellites in their orbits; the more massive a planet is, the more distant its satellites. For example, Saturn, one of the gas giants, has the most known moons. Stars themselves orbit around the center of the galaxy.

Newton's three laws of motion are also applicable for understanding the effects of gravity on the cosmic law, particularly the first and third law. The first law states that an object at rest or in motion will remain in that state until something acts on it; this explains why planets and moons stay in their orbits. The third law is that for every action, there is an opposite and equal reaction. While this is negligible when considering something like a planet affecting a star, this explains tides on Earth, which are caused by the moon's gravity.

Newton understood how gravity worked, but not why. It wasn't until Albert Einstein's General Theory of Relativity, published in 1915, that a theory was postulated to explain the cause of gravity. Einstein showed that gravity was not a quality inherent to objects, but instead it was caused by curves in the space-time dimensions, which is what all objects rest on. Thus, even light and other massless phenomena are affected by gravity.

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Relationship Between Gravity & the Mass of the Planets or Stars

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The more massive a planet or star is, the stronger the gravitational force it exerts. It is this force that allows a planet or star to hold other objects in their orbit. This is summed up in Isaac Newton's Universal Law of Gravitation, which is an equation for calculating the force of gravity.

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Science Questions with Surprising Answers

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There is gravity in space – lots of it. Gravity is everywhere. It is true that as you get farther from the earth, its gravitational pull weak...

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Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.

What else does gravity do?

Why do you land on the ground when you jump up instead of floating off into space? Why do things fall down when you throw them or drop them? The answer is gravity: an invisible force that pulls objects toward each other. Earth's gravity is what keeps you on the ground and what makes things fall.

Anything that has mass also has gravity. Objects with more mass have more gravity. Gravity also gets weaker with distance. So, the closer objects are to each other, the stronger their gravitational pull is.

Earth's gravity comes from all its mass. All its mass makes a combined gravitational pull on all the mass in your body. That's what gives you weight. And if you were on a planet with less mass than Earth, you would weigh less than you do here.

You exert the same gravitational force on Earth that it does on you. But because Earth is so much more massive than you, your force doesn't really have an effect on our planet.

Gravity in our universe

Gravity is what holds the planets in orbit around the sun and what keeps the moon in orbit around Earth. The gravitational pull of the moon pulls the seas towards it, causing the ocean tides. Gravity creates stars and planets by pulling together the material from which they are made.

Gravity not only pulls on mass but also on light. Albert Einstein discovered this principle. If you shine a flashlight upwards, the light will grow imperceptibly redder as gravity pulls it. You can't see the change with your eyes, but scientists can measure it.

Black holes pack so much mass into such a small volume that their gravity is strong enough to keep anything, even light, from escaping.

Gravity on Earth

Gravity is very important to us. We could not live on Earth without it. The sun's gravity keeps Earth in orbit around it, keeping us at a comfortable distance to enjoy the sun's light and warmth. It holds down our atmosphere and the air we need to breathe. Gravity is what holds our world together.

However, gravity isn't the same everywhere on Earth. Gravity is slightly stronger over places with more mass underground than over places with less mass. NASA uses two spacecraft to measure these variations in Earth's gravity. These spacecraft are part of the Gravity Recovery and Climate Experiment (GRACE) mission.

GRACE detects tiny changes in gravity over time. These changes have revealed important details about our planet. For example, GRACE monitors changes in sea level and can detect changes in Earth's crust brought on by earthquakes.

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Gravity is the force by which a planet or other body draws objects toward its center.

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How does gravity work in space?

Gravity is a very important force. Every object in space exerts a gravitational pull on every other, and so gravity influences the paths taken by everything traveling through space. It is the glue that holds together entire galaxies. It keeps planets in orbit. It makes it possible to use human-made satellites and to go to and return from the Moon. It makes planets habitable by trapping gasses and liquids in an atmosphere. It can also cause life-destroying asteroids to crash into planets.
A sk any question below to learn about gravity in space.

What is gravity?
Is there gravity in space?
How do scientists know what the path of an object in space will be?
What causes an orbit to happen?

Can gravity affect the surface of objects in orbit around each other?

What's a gravity well?

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Gravity is a very important force. Every object in space exerts a gravitational pull on every other, and so gravity influences the paths taken by everything traveling through space. It is the glue that holds together entire galaxies. It keeps planets in orbit.

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The solar system consists of the Sun and everything that orbits, or travels around, the Sun. This includes the eight planets and their moons, dwarf planets, and countless...

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Size and Distance Our solar system extends much farther than the eight planets that orbit the Sun. The solar system also includes the Kuiper Belt that lies past Neptune’s orbit. This is a sparsely occupied ring of icy bodies, almost all smaller than the most popular Kuiper Belt Object – dwarf planet Pluto. Beyond the […]

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Orbit of the Planets in the Solar System

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Why Do We Have Different Seasons? | California Academy of Sciences

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After Effects Tips & Treats - by Julien Schickel

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Year On Every Planet In Solar System || (Revolution Time Around The Sun)