Moon would “disappear” when it no longer reflected Sun’s light.
It would also start getting very cold fast
Does heat travel at the speed of light? I just realized I have no idea how the heat from the sun travels to earth.
Someone correct me if I’m missing some nuance here, but heat doesn’t get transferred directly through space because heat is vibrating molecules and space is a vacuum. The sun radiates (speed O’ light). A lot of that radiation just reflects off the earth (or we wouldn’t be able to see it), but a lot of it gets absorbed. THAT’s when it’s converted into heat energy. It’s also why the greenhouse effect is a global phenomena: light energy comes in across the vacuum relatively easily, turns to heat on Earth instead of being reflected, heat energy cannot escape as easily as light energy.
Infrared light is absorbed quite easily, producing heat, and the sun emits a lot of it. Of course, all photons that are absorbed and not reflected will produce thermal energy, and infrared radiation is commonly referred to as radiant heat. The other two heat transfer methods are conduction and convection, which requires a medium to transfer through.
When there is a total solar eclipse, the temperature does drop dramatically. But it might not be detectable on the other side right away for sure.
Any visible planet or asteroid would. So some stars would also appear to blink out, but those would take longer to blink out. So the moon would go after 8 minutes, Jupiter would take 43 minutes to stop receiving light, and another 35-52 minutes to disappear for earth depending on orbital locations.
Presumably we would get something on radio/tv/internet from the side facing the sun once they realized it, that of course being only if they hadn’t already been eradicated by a horrific shockwave caused by whatever event caused the sun to vanish before they had a chance to report what they saw, because supernovae tend to travel at very close to the speed of light, so there wouldn’t be much time for them to react.
And if this is a supernova, you might just have time to grok what happened before the planet was obliterated under your feet from the shockwave.
So I guess… chances are we would just barely understand what happened before we were gone.
