We can learn a lot from the light of the star and the planet that reaches us!
If we can detect how much the star moves because of the planet, we can figure out the mass.
If we can see how much of the star’s light is blocked when the planet passes in front of it, we can figure out the radius. If we do that for different types of light, we can even figure out things about the planet’s composition and temperature
And that’s just the beginning!
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