gravity
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From collapse to solar system
Once upon a time, there was a huge interstellar cloud of cold, low-density gas called the solar nebula. This solar nebula came about from billions of years of galactic recycling, and consists of about 98% hydrogen and helium and 2% other random elements. The solar nebula collapsed under its own gravity, and BOOM! the Sun… Continue reading
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Gravity holds the universe together
Gravitational force, why planets have orbits, and how we know that black holes exist When you think of gravity, you might think of the force that makes apples fall on people’s heads (talking about you, Newton!). But it’s also why planets have orbits! Any two objects in space have a gravitational force between them. Kepler’s… Continue reading