Examples / Astronomy
How does the solar system work?
Drawn and explained by Sketchwise from this one question.
The explanation, step by step
1. The Sun at the centre
This is our solar system, and at its very heart burns one star: the Sun. I hold almost all the mass here, so my gravity pulls on everything around me.
2. The rocky planets
Close to the Sun, four small rocky planets circle round, each on its own orbit. Earth is the third, taking one whole year for each trip, and red Mars comes next.
3. Why planets orbit
But why don't the planets fall into me, or simply fly off into space? Each planet is racing forward, Earth at about thirty kilometres every second. At the same time, the Sun's gravity keeps tugging it steadily inward. Speed plus that inward pull bends its path into a curve that never ends: an orbit.
4. The giant planets
Beyond a belt of rocky asteroids, giant planets made mostly of gas and ice roam. Out here the Sun's pull is weaker, so Uranus and Neptune crawl slowly round.
5. One balanced system
Every planet is falling toward the Sun and racing sideways, both at once. That balance of speed and gravity is how our whole solar system works!
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