We measure space objects speed in relation to earth. But since earth is also moving through space, how do we know the true speed of objects without a universal “non moving” point?

Question

The speed of an object is measure relative to the observer. But since all objects are moving in relation to all objects, how can we know the true speeds of things? Wouldnt two observers on different planets measuring an object in space come up with different answers?

In: Physics

Answer 1

it might give you vertigo to think *we dont!*.

I once got caught in a blizzard on a snowboard. I couldn’t see so I slowed down and stopped to regroup.
Then I sat down.
Turns out i hadn’t stopped, it was just so white and noisy and powdery that I had no cues left about my speed relative to earth.

I ate shit in the most unexpected way.