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a shimmering light in Earth's Polar regions, which is a result when high-energy-charged particles from solar wind are carried past Earth's magnetic field, generating electrical currents that flow toward the poles. Electric currents charge the gases in upper atmosphere.
a flying ball of dust, ice, gas and rocks. The tail is a reflection of sun's light (white) or gases ionized by radiation (blue). It will always orbit until it dissipates (dies out)
sun casts a shadow of Earth that completely covers moon. No light from sun can reflect off moon, therefore moon disappears.
object that orbits one or more stars, but is not a star itself. It does not share its orbit with another object.
the result of collisions that build rock debris. Eventually will combine into a planet after enough rock debris.
direction opposite to movement of something else. Since the orbits of the planets are of different sizes, they take different amounts of time to revolve around Sun. From Earth, their apparent motion resembles a loop.
when moon is between Earth and sun, casting shadow onto earth. Sun's light is blocked out, but it is still harmful to watch.
large eruptions of luminous hydrogen gas that rise thousands of km above chromosphere.
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