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earth and the planets revolve around the SUN


earth is the center of the revolving planets and stars


an oval shape , which may be elongated or nearly circular


central region of the SUN

nuclear fusion

hydrogen atoms join to form helium

radiation zone

a region of very tightly packed gas where energy is transferred mainly in the form of electronic radiation

convection zone

the outer most layer of the SUNs interior


inner layer of the SUNs atmosphere


middle layer of the SUNs atmosphere


the outer layer of the SUN

solar wind

streams of electrically charged particles


areas of gas on the suns surface that are coller then the gases around them


A loop of gas that protrudes from the sun's surface, linking parts of sunspot regions

solar flare

gas eruptions into space

terrestrial planets

the four inner planets

greenhouse effect

The process by which certain gases (principally water vapor, carbon dioxide, and methane) trap heat that would otherwise escape the earth and radiate into space

gas giant

4 outer planets


thin disc or small particles of ice and rock


loose collections of ice , dust, and small rocky particles whose orbits are usually very long, narrow ellipses


too small rocky objects too small and too numerous to be considered full fledged planets


a chunk of rock or dust in space


(astronomy) any of the small solid extraterrestrial bodies that hits the earth's atmosphere


a meteoroid that strikes the surface of a moon or planet

extraterrestrial life

life other than that on Earth.

Kuiper belt

a doughnut - shaped region that extend beyond NEPTUNES orbit about 100 times Earth's distance from the SUN

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