If two spaceships travel in opposite direction at .6c (the speed of light) from earth, then why aren’t they exceeding the speed of light relative to each other?

Question

I understand that if I am standing on earth and a space ship takes off and travels at .6c, then I perceive the space traveler receding at .6c relative to me, and the space traveler perceive me as receding at .6c relative to him. If another traveler takes off in the 180-degree opposite direction, then likewise I perceive the other space traveler receding at .6c relative to me, and the other space traveler perceive me as receding at .6c relative to him.

So why don’t they perceive each other as traveling faster than c, the speed of light?

In: 29

Answer 1

Because of time dilation and length contraction.

Remember velocity is distance over time.

In relatively those two things are not absolute they are relative to The Observer.

What you as a stationary Observer thinks is certain distance in a certain time someone on the spaceship does not