GLY 1001 Earth Science
Chapter 22 Vocabulary
1. Asteroid – thousands of small planet-like bodies, ranging in size from a few hundred kilometers to less than a kilometer, whose orbits are mainly between those of Mars and Jupiter.
Coma – The fuzzy, gaseous component of a comet’s head.
2. Comet - A small body that generally revolves around the Sun in an elongated orbit.
Escape velocity – The initial velocity an object needs to escape from the surface od a celestial body.
3. Inner planets - Any of the Earth-like planets, including Mercury, Venus, mars and Earth.
Iron meteorite – One of the three main categories of meteorites. This group is composed largely of iron with varying amounts of nickel (5-20%).Most meteorite finds are of this type.
4. Jovian planets – Jupiter-like planets: Jupiter, Uranus, Neptune, and Saturn which have very low densities.
Kuiper belt – A region outside
the orbit of
Lunar highlands – The extensively cratered highlands of the Moon.
Lunar regolith – A thin gray layer on the surface of the Moon, consisting ofloosely compacted, fragmented material believed to have been formed by the repeated meteorite impacts.
Maria – The Latin name for the smooth areas of the Moon formerly thought to be seas.
6. Meteor – The luminous phenomenon observed when a meteoroid enters Earth’s atmosphere and burns up
7. Meteorite – Any portion of a meteoroid that survives the traverse through Earth’s atmosphere and strikes the Earth’s surface
8. Meteoroid - Small solid particles that have orbits in the solar system
Meteor shower – Many meteors appearing in the sky caused when Earth intercepts a swarm of meteoritic particles.
Oort cloud – A spherical shell composed of comets that orbit the Sun at distances generally greater than 10,000 times the Earth-Sun distance.
9. Outer planets – Jupiter-like planets: Jupiter, Uranus, Neptune, and Saturn which have very low densities.
Stony-iron meteorite – One of the three main categories of meteorites. This group, as the name implies, is a mixture of iron and silicate minerals.
Stony-meteorite – One of the three categories of meteorites. Such meteorites are composed largely ofsilicate minerals with inclusions of other minerals.
Terrae - The extensively cratered highlands of the Moon.
10. Terrestrial planet - Any of the Earth-like planets, including Mercury, Venus, mars and Earth.