Question

What is a brown dwarf and what distinguishes from a planet or a star?

Answer 1

The stars is formed from a cloud of contracting gases. As a result the temperature in it become so very high and causes the fusion of hydrogen to form helium. This produces enormous amount of energy causing the stars to shine under its own power. Also the stars are located far away from the earth. So the light from the star gets refracted as it passes through the different layers of earth. This causes the twinkling of stars when we observe it.

A planet is formed by the collision and sticking together of leftover dust particles from the formation of a star. There is not enough temperature in a planet to cause a fusion like that in a star and thereby produce energy. So the planets cannot produce its own light. The planets in our solar system are much closer to earth. The light we see from the planets are the reflection of sunlight from the planet. Since the planets are much close to the Earth than stars, the refraction of light is small compared to those of stars. So planets do not twinkle.

Brown dwarfs are objects which are too large to be called as planets and too small to be called as stars. They have masses ranging from 12 times to 75 times the mass of the planet Jupiter. They are thought to form contracting clouds like the stars. But it cannot initiate the fusion process as the cloud collapes. Brown dwarfs are very dim and cool compared to the stars. Their light is the leftover from their initial formation.