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

Yes, but the beam is continuously diverging, so over astronomical distances the bright beam is more like a couple photons which are not as significant when you consider the sea of cosmic radiation stars emit.