Solar System
consists of the sun, planets, their moon, and a variety of smaller objects
Astronomical Unit
scientists use these units to measure distance in solar system
Planet
is an object that orbits the sun, is large enough in have become rounded by its own
Dwaft Planet
object that orbits the sun and has enough gravity to be spherical, but has not cleared the area of its orbits.
Planetisimal
these are formed by gravity pulling rock, ice and gas together. Eventually they collide and stick together.
Geocentric
earth is at the center of the revolving planets and stars (Ancient).
Heliocentric
earth and other planets revolve around the sun (modern).
Terrestrial Planet
small, dense planets with rocky surfaces.
Greenhouse Effect
trapping of heat by the atmosphere
Inner Planets
Mercury, Venus, earth, and Mars.
Gas Giant
the largest four planets
Ring
thin disk of small particles of ice and rock that surrounded the gas giants.
Outer Planets
Jupiter, Saturn, Uranus, and Neptune.
Asteroid Belt
region of the solar system between Mars and Jupiter.
Kuiper Belt
beyond Neptune's orbit is this region which extends to about 100 time earth's distance from the sun.
Oort Cloud
this region stretches out more than 1000 time the distance between the sun and Neptune.
Comet
loose collections of ice, dust and small rocky particles.
Coma
clouds of gas and dust form a fuzzy outer layer
Nucleus
the solid inner core of a comet
Asteroid
rocky objects, most of which are too small and too numerous to be considered planets and dwaft planets
Meteoroid
chunks of rock or dust smaller than asteroids
Meteor
when a meteoroid enters earth's atmosphere, friction with the all creates heat and produces a streak of light
Core
central region of the sun where nuclear fusion takes place
Nuclear Fusion
a process where two atomic nuclei form another element which released huge amount of energy.
Radiation Zone
region of very tightly packed gas where energy moves mainly in the form of electromagnetic
Convection Zone
outer most layer of the sun's interior
Photoshpere
inner layer of the sun's atmosphere that gives off it visible light
Chromosphere
middle layer of the sun's atmosphere that creates a glow around the edges of the total eclipse
Corona
the outer layer which looks like a white halo around the sun. This occurs during a total solar eclipse.
Solar Wind
streams of electrically charged particles that ematate from the sun's surface