anneguineapig

It is possible for planets to form and hopefully this page will give you some more information on how they are formed.

What is the definition of a planet?
A planet is a spherical object that orbits a star. If it does not orbit a star but another land mass then it is considered a moon. It also has to be large enough to create a force of gravity.

How was the sun formed?
The sun was formed from a large cloud of gas and dust. The strength of gravity in the centre of the cloud causes the gas to get more and more dense, until the pressure and temperature increase and a star begins to form due to nuclear reactions.

How is a planet formed?
A planet is made from the remaining atoms left over from star formation. These atoms were pulled into orbit around the star by gravity. Over time these atoms stuck together to create planets. The planets are usually spheres because the force of gravity is even.

Planets could have formed as early as 14 billion years ago. The planets in our solar system formed about 4.5 billion years ago. New planets are still forming today around other stars.

Can a planet form over a large period of time?

Yes new planets form over long time periods. It has to form from material floating in space and therefore is unlikely that one will form in our solar system as most of the matter has already formed planets.