Space Revision Crossword

Clumps of metal and rock. Mainly found in the asteroid belt, located between Mars and Jupiter
Objects consisting of rock, dust and ice that travel in the universe at high speeds. When they approach the sun they vaporise and produce a trail.
An astronomical unit of distance. One ly is equal to the distance that light travels through space in a single year.
The galaxy in which our solar system is located
A body that has a sufficiently large mass and that orbits a star. Our solar system contains 8 of these, all of which orbit the sun.
A star formed from a cloud of dust and gas being pulled together by gravitational attraction. Fusion reactions occur here.
A large system of billions of galaxies
A system containing billions of stars
Planets that have a gaseous composition, often involving hydrogen and helium. These are Neptune, Jupiter, Uranus and Saturn in our solar system
Planets that have a solid composition, often composed of metals or rocks. These are Mercury, Venus, Earth and Mars in our solar system.