An asteroid is like a planet, but smaller. The name “asteroid” means “like a star” in the ancient Greek language. Asteroids may look like small stars in the sky, but they really do move around the Sun, while stars only seem to move because the Earth spins. Like planets, asteroids do not make their own light. Because of this, some people think “asteroids” is not a good name, and think that the name “planetoid” (“like a planet”) would be a better name.

Most asteroids are made of rock, but some are made of ice or metal. Most asteroids in our Solar System are in the asteroid belt between Mars and Jupiter.

A nebula is usually made up of hydrogen gas and plasma. It is the first stage of a star’s cycle. There are four different types of nebula. These are; Emission, Reflection, Dark, and Planetary. Opinions on the number of Nebulae do vary, however, and some of these other types include Planetary and Bright nebula. In the past Galaxies and Star Clusters were also thought to be certain types of nebulae.

Body               Years     Days

1.Eris                   557           295

2.Makemake      310          33

3. Pluto              247         256

4. Neptune        164         298

5. Uranus           84            4

Venus and Mercury are the only planets in the solar system with years of shorter duration than earth years -225 and 88 days respectively .

Moon / Planet               KM          MILES

Ganymade(Jupiter)       5262.4     3,269.9

Titan (saturn)                   5150.0      3200.1

Callisto(Jupiter)             4820.6     2995.4

LO (Jupiter)                     3642.6      2995.4

Moon (Earth)                   3476.2      2160.0