Eli5: If a laser is shined into space will it continue to infinity (if it doesn’t hit a solid object)?

Question

Seems like a gargantuan, if not infinite amount of energy would be required for this to occur

In: 10

Answer 1

That isn’t just true for light.

If you were launched into space, and didn’t hit anything, you would also continue forever.

It doesn’t take energy to continue motion at constant speed.