Space & Astronomy Facts
Black holes, distant planets, and the vast mysteries of the cosmos.
Black Holes
Where gravity is so strong that not even light can escape.
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Mars
The Red Planet has the tallest mountain and deepest canyon in the solar system.
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The Moon
Footprints there will last 100 million years, because there's no wind to blow them away.
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The Visible Universe
93 billion light-years across, two trillion galaxies, and expanding faster than light.
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The Milky Way Galaxy
Our home galaxy: 100,000 light-years across, hundreds of billions of stars, and a supermassive black hole at its heart.
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Stars
Born in nebulae, fusing 1.3 trillion pounds (600 billion kg) of hydrogen per second, dying as white dwarfs, neutron stars, or black holes. The engines of the universe.
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The Sun
A G2V yellow dwarf 93 million miles away, fusing 600 million tons of hydrogen every second. Our local star, and the source of nearly all of Earth's energy.
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