Space Questions

Ya.. Mjord answered your question....

The post is somewhat difficult to understand. First of all, person [A] wouldn't see the planet explode until millions of years after it exploded, but lets say he saw that in the future it would explode. There is no reality coming towards him -- just light. [B] would already be dead. [A] couldn't save [B]. There is no alternate reality. The fact that [A] could still see the planet is due to the lag between what's happening at point [B] and the time it takes light to get here.

Just for completeness, I'll add and rephrase.

First off, [A] cannot see into the future. It's not possible. If someone could see into the future, they wouldn't be able to change a motherfucking thing, because the future would be the future. It's simple causality. If you know what will happen, then whatever the fuck you do doesn't matter. Know why? Because you know what will happen.

Secondly, if [A] could see [B]'s planet exploding before everyone else on Earth saw it (i.e. he was close to it when it happened), he could tell everyone on Earth that it was going to blow up and be held as a prophet when the light showing planet [B] exploding reached Earth. He could not, however, contact anyone on planet [B] because at time of transmission, it would be space dust.