Standard 7. Solar System Ch 25

unit of length that is used in astronomy; equals distance between Earth and sun.

• light year
• astronomical distance
• astronomical mile
• astronomical unit

celestial body orbiting a star that meets all the criteria of a planet except that it has not cleared its orbit of other objects.

• planet
• asteroid
• dwarf planet
• moon

cloud of gas and dust in space

• nebula
• comet
• cumulonimbus
• gas giant

nuclear reaction in which 2 nuclei fuse to form a larger nucleus and release a large amount of energy

• nuclear fission
• nuclear fusion
• nuclear shower
• flexcompacitorion

celestial body orbiting a star that has enough gravity to be spherical and has cleared its orbit of smaller objects.

• planet
• moon
• dwarf planet
• comet

our sun and all of the objects that revolve around it because of the sun's gravity.

• universal studios
• universe
• universal system
• solar system

one of the 4 planets closest to the sun that are solid, dense, and rocky; Mercury Venus, Earth, or Mars

• inner planets
• outer planets
• dense planets
• inside personal space planets

amount of time it takes for a planet to complete one revolution around the sun

• light year
• astronomical unit
• year
• month

Jupiters four largest moons, which were discovered by Galileo

• Galilean moons
• Kuiper belt
• Galileonionaial moons
• Gavineal moons

one of the 4 outer planets, which are composed mainly of the gases hydrogen and helium

• gas giants
• hydrogen giants
• hydro-helium giants
• big gasers