Describe what comets are like when they are very far from the Sun.What is this region of space called?

Question

What happens to comets when they enter the inner soloar system? If comets are made up mostly of icy material, why do they last so long?

Answer 1

Far from the Sun they are like snowy dirt-balls - a combination of ice and rock.

Comets come from two regions - the Kuiper Belt and the Oort Cloud.

When a comet comes in toward the Sun, it warms up so the ices sublimate (turn to gas) and form something like an atmosphere around the comet. This gas gets blown away from the Sun by radiation pressure and the solar wind to form the comet's tail.

Comets that come in towards the Sun do eventually disappear - they lose about 2% (I think, but I could be wrong) of their mass with each pass. But since most comets that do come into the inner solar system have periods of hundreds to thousands of years, they can last a pretty long time.

Answer 2

Asteroid belt. Was supposed to be a planet and exploted into thousands pieces. This is a far asteroids are concerned. When they enter the inner solar system their ice melts and trails behind them, hence the tail. Probably they dont stay for long in the sun to get toasted.

Answer 3

kris is spot on