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If we apply this question to the moon and ask why the moon does not fall to Earth, then we are stating the question that vexed scientists (and others) for centuries until Isaac newton arrived at the Universal Law of Gravitation.
That law says that the force of gravity between two objects is inversely proportional to the square of the distance between them and proportional to the product of the masses of the two objects. The "universal" part of this is that the same law applies to all objects with mass in the universe and applies with the same proportionality constant which we call the gravitational constant, G.
With the force so prescribed, the answer as to the motion of objects is determined by the other three Newtonian laws of motion.
Now, the answer applies to planets around stars and moons around planets and rotating binary stars and even galaxies that are mutually rotating and bound by the force of gravity.
It was Kepler who discovered that the orbits were elliptical but did not know why. Newton calculated the orbits and proved it mathematically.
While it is possible to simply ask "why," it is also possible to answer by saying that to do otherwise would violate the laws of physics. One could ask why the moon doesn't change direction and go backwards occasionally and the answer to that would be that it violated the laws of physics.
Alternatively, one can say that the centripetal force of a planet in circular motion is provided by gravity and is exactly equal to the force required to overcome the effect of inertia tending to keep the body moving in a straight line. (This latter is the apparent force called the centrifugal force.)
If the force of mutual attraction were not an inverse square force, objects would still rotate about there center of gravity, but the result would not necessarily be elliptical or regular. The resulting motion would, however, still satisfy Newton's laws of motion and the force of attraction would still exactly match that require to overcome the inertial tendency of the objects to move in a straight line.
So, because of gravitational attraction planets do not move in a straight line and the deviation from a straight line is caused by gravity and the resulting path is the orbit.
One final caveat is required. The effects of both Special and General Relativity are not taken into account in this answer, but those have no substantial consequence for normal planets and normal stars. Black holes would lead to a more complex situation.
What else can I help you with?
Does every planet revolve around earth?
No, none of them do. Planets revolve around stars, so all of the planets in our solar system orbit the Sun, our own star.
In what type of system do the Earth Sun planets and stars revolve?
The Sun, Earth and other planets, along with many other items are part of a Solar System.
Do stars revolve around satellites?
No, stars revolve around the galactic center.
What do the planets do around the sun?
They revolve.
How are stars and planets the same and how do they differ?
Similarities: Stars and planets can appear the same - like pinpoints of light in the night sky. Differences: Planets are rock or gas, and do not glow by themselves but reflect the light of stars which illuminate them. Stars fuse hydrogen into helium and give off enormous amounts of energy, some in the visible range. Stars are MUCH bigger than planets.
What are characteristic of planets?
planets do not shine with their own energy but shine because of energy of stars. they revolve around stars
What do planets revolve around?
Planets orbit stars. Our planet (earth) orbits a star we call the sun.
Does every planet revolve around earth?
No, none of them do. Planets revolve around stars, so all of the planets in our solar system orbit the Sun, our own star.
Why did sailors use the stars and not the planets to find their way at sea?
Because stars not like planets revolve and stars last at the night sky for many many years even at your lifetime.
Do the stars orbit the planets or do planets orbit stars?
Moons orbit planets. Planets orbit stars. Some stars orbit other stars, or orbit their mutual center of gravity. Stars orbit the center of the galaxy. Galaxies may orbit the center of the "galactic group".
Are there more Stars or Planets?
there are more planets than stars because to every star there could have several planets
In what type of system do the Earth Sun planets and stars revolve?
The Sun, Earth and other planets, along with many other items are part of a Solar System.
Do stars revolve Jupiter?
No, stars do not revolve around Jupiter. Instead, Jupiter orbits the Sun along with other planets in our solar system. Stars are distant celestial bodies that have their own orbits and are not affected by individual planets like Jupiter.
Are stars distant planets?
Stars are not planets. They are like our sun and may or may not have planets orbiting around them. Stars are hot and the heat makes them look like bright lights in the sky on a clear night. Planets do not create very much, if any, visible light and are much harder to see because they only reflect the light from stars.
What do moons revolve around?
They revolve around planets.
Do all planets revolve and rotate?
Yes, all the planets in our solar system revolve and rotate.
Do stars revolve around satellites?
No, stars revolve around the galactic center.
