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A rocky object revolving around the sun that is too small and numerous to be considered as a planet.
The region of the solar system, between the orbits of Mars and Jupiter, where many asteroids are found.
A loose collection of ice, dust, and a small rocky particles, typically with a long, narrow orbit.
a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy.
The name often given to the first four outer planets: Jupiter, Saturn, Uranus, and Neptune.
A model of the universe in which Earth is at the center of the revolving planets and stars.
A model of the solar system in which Earth and the other planets revolve around the sun.
A doughnut-shaped region that stretches from beyond Neptune's orbit to about 100 times Earth's distance from the sun.
A region of very tightly packed gas in the sun's interior where enrgy is transferred mainly in the form of light.
An eruption of gas from the sun's surface that occurs when the loops in sunspot regions suddenly connect.
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