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The visible surface of the sun

solar prominance

A bright loop in the Sun's corona


The sun's atmosphere


A dark spot on the photosphere of the sun

radiation zone

Energy from the star moves out through this zone


Most of the Sun's mass is in this layer

solar flare

A brief burst of energy from the sun's photosphere

solar wind

A fast-moving stream of particles thrown into space by solar flares

convection zone

In this zone, cooler particles are pulled down by gravity


The combining of hydrogen particles


Hot bright areas, gives a grain look to the surface of the Sun


Group of stars, gas and dust


Distance light travels in one year


Most common type of star


Everything that exists

apparent magnitude

How bright a star appears to be

absolute magnitude

The actual brightness of the star

spiral galaxy

Arms of the galaxy contain young stars, protostars, dust and gas

barred galaxy

it is similar to a spiral galaxy but the spiral extends from a bar of stars that stretches from the center

elliptical galaxy

They range from almost spherical like a baseball to to a shape like a flattened football they do not seem to rotate

irregular galaxy

Group of stars with not obvious shape

white dwarf

The star continues to shine dimly for billions of years as it slowly cools

red giant

The star may expand to 100 times its former size.


A star begins within a huge cloud of hydrogen, helium, and tiney particles of dust


After millions of years, the particles begin to squeeze together, attracted to each other by gravity. As it grows in mass, its temperature rises until it begins to glow

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