I know it takes like 8 minutes for sunlight to reach earth, so does that mean that we experience the eclipse 8 minutes after it happens? I understand that the moon isn’t nearly as far so it’s probably more of just the moon going in front of it, but it confuses me because we still see the ray of sunlight around the moon at totality, so is that light “8 minutes old”?
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All the light you ever see from the Sun is about 8 minutes old. Of course, the exact age depends on how far the Earth is from the sun, which changes throughout the year. But it is always pretty close to 8 minutes, so any photons you see that came from the Sun were emitted by it about 8 minutes ago.
The speed at which the eclipsed area moves across the Earth is not limited by the speed of light, it is limited by the projected speed of the Moon onto the Earth, as you expected. An eclipse is a shadow. The Moon lines up with the Sun and blocks its light from reaching Earth. The Moon is about 1.3 light seconds away from Earth. So when the eclipse is just starting, that last ray of light that reaches you before totality was emitted by the Sun about 8 minutes ago, but passed by the Moon about 1.3 seconds ago. Meaning that you see the eclipse begin and end about 1.3 seconds after the geometrical alignment of the sun, the edge of the moon, and the place you are standing on the Earth.
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