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Does the Earth orbit around where the Sun was 8.5 mins ago?
Interesting thought huh? Gravity like all e-m radiation radiates at lightspeed. The Sun and Earth are each moving at about 60,000km/hr. Light from the Sun, like gravity from the Sun takes 8.5 minutes to reach us. In that time the Sun has moved about 8,000km from where we saw it.
If the Sun suddenly wasn't there we'd keep orbit around were it last was 8.5 minutes ago for 8.5 minutes until we noticed it was gone!
So isn't it strange, we are orbiting around the Sun we see - because its obivously the Sun were it was 8.5 minutes ago from our frame of reference. So move the Sun forward about 1/2 a Sun's diammeter in the sky - and that is where the Sun really is!
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