1.
an attractive force that exists between between all objects that have mass
2.
huge collections of gas dust and stars held together by gravity
3.
one of 3 types of known galaxies
4.
one of 3 types of known galaxies
5.
one of 3 types of known galaxies
8.
approximate shape of ALL known galaxies
10.
objects in space ranging from a grain of sand to small asteroid
11.
meteoroid that has entered Earth's atmosphere and is burning up
12.
piece of a meteoroid that lands on Earth
13.
was formed from a rotating cloud of gas, ice and dust
14.
a rotating cloud of gas, ice and dust
15.
atoms move more quickly when they are __________