Expanded older star
A red giant is a star that has grown very large as it reaches a later stage of life. Its outer layers expand and its surface becomes cooler than before.
A red giant is a later-life stage in which a star grows much larger than before.
A huge red-orange giant star glowing brightly.
A red giant is a later-life stage in which a star grows much larger than before.
As the balance inside a star changes, its outer layers expand. The star becomes enormous even though its outer surface is cooler than earlier in life.
A red giant shows that stars change over time. They are not fixed lights that always stay the same.
A Sun-like star later sheds outer layers and leaves a hot core behind. That core can become a white dwarf.
Imagine a giant glowing red-orange sphere that has swelled far beyond the size it once had.
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