Background Info

All the planets, asteroids, meteoroids, and comets in the solar system orbit the sun. This is called heliocentric orbit.

Almost all these bodies also travel in the same orbital plane, a thin disk surrounding the sun and extending to the edge of the solar system. The orbital plane usually prevents planets or other celestial bodies from bumping into each other.

Some comets orbit outside the orbital plane, perpendicular or at an angle to the rest of the solar system bodies.

For Further Exploration

Vocabulary

Term Part of Speech Definition Encyclopedic Entry

asteroid

Noun

irregularly shaped planetary body, ranging from 6 meters (20 feet) to 933 kilometers (580 miles) in diameter, orbiting the sun between Mars and Jupiter.

celestial body

Noun

natural object in space, such as a planet or star. Also called an astronomical object.

comet

Noun

celestial object of matter surrounded by ice and dust that orbits the sun and leaves a tail of debris.

heliocentric orbit

Noun

regular path around the sun.

meteoroid

Noun

small, rocky body traveling around the sun.

Encyclopedic Entry: meteoroid

orbit

Verb

to move in a circular pattern around a more massive object.

Encyclopedic Entry: orbit

orbital plane

Noun

flat space in which a body orbits.

perpendicular

Noun

at a right angle to something.

planet

Noun

large, spherical celestial body that regularly rotates around a star.

Encyclopedic Entry: planet

solar system

Noun

the sun and the planets, asteroids, comets, and other bodies that orbit around it.

sun

Noun

star at the center of our solar system.

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Illustrator

Tim Gunther, Illustrator

Page Producer

Makayla Trotter

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