Why do celestial bodies keep moving

As her arms come closer to her axis of rotation, her speed increases and her angular momentum remains the same. Similarly, her rotation slows when she extends her arms at the conclusion of the spin.

As an interstellar cloud collapses, it fragments into smaller pieces, each collapsing independently and each carrying part of the original angular momentum. The rotating clouds flatten into protostellar disks, out of which individual stars and their planets form. By a mechanism not fully understood, but believed to be associated with the strong magnetic fields associated with a young star, most of the angular momentum is transferred into the remnant accretion disk.

Planets form from material in this disk, through accretion of smaller particles. In our solar system, the giant gas planets Jupiter, Saturn, Uranus, and Neptune spin more rapidly on their axes than the inner planets do and possess most of the system's angular momentum. The sun itself rotates slowly, only once a month. The planets all revolve around the sun in the same direction and in virtually the same plane.

In addition, they all rotate in the same general direction, with the exceptions of Venus and Uranus. These differences are believed to stem from collisions that occurred late in the planets' formation.

If planets were bigger, the force between them and the sun would be larger and it would alter their orbits. Similarly, the equation shows that the distance of the planet from the sun is also a crucial factor in establishing an orbit. The physical law that states that objects in motion have a tendency to remain in motion also plays a role in keeping the planets in orbit.

This set the planets into motion from their birth. Once the planets were in motion, the laws of physics keep them in motion by virtue of inertia.

The planets continue to move at the same rate in their orbits. The gravity of the sun and the planets works together with the inertia to create the orbits and keep them consistent. The gravity pulls the sun and the planets together, while keeping them apart. The inertia provides the tendency to maintain speed and keep moving. The planets want to keep moving in a straight line because of the physics of inertia.

However, the gravitational pull wants to change the motion to pull the planets into the core of the sun. Together, this creates a rounded orbit as a form of compromise between the two forces. The speed, or velocity, of the planets plays a big role in their orbits, including the shape of the orbit. For a planet to remain in orbit around the sun and not fall into it, the planet must have a speed fast enough to keep it at a certain distance from the sun.

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