# The Naked Scientists Forum

### Author Topic: can two objects travel away from eachother at more than the speed of light?  (Read 2385 times)

#### bizerl

• Sr. Member
• Posts: 279
##### can two objects travel away from eachother at more than the speed of light?
« on: 17/07/2012 01:04:33 »
I apologise if this has already been addressed on the forum, but here goes...

If a ship accelerates to say, two thirds the speed of light, while another ship accelerates to the same speed from the opposite direction, are they actually moving towards each other at more than the speed of light? What would a person on each ship see as they approached and as they passed (ignoring the obvious limitations of human sight)? How is this different from a ship moving away from the earth at 1.33... times the speed of light?

#### simplified

• Sr. Member
• Posts: 428
##### Re: can two objects travel away from eachother at more than the speed of light?
« Reply #1 on: 17/07/2012 04:33:34 »
I apologise if this has already been addressed on the forum, but here goes...

If a ship accelerates to say, two thirds the speed of light, while another ship accelerates to the same speed from the opposite direction, are they actually moving towards each other at more than the speed of light? What would a person on each ship see as they approached and as they passed (ignoring the obvious limitations of human sight)? How is this different from a ship moving away from the earth at 1.33... times the speed of light?
We can not make map of our galaxy to every speed of ship. Ships should use map with motionless coordinates concerning of central black hole.What is time they want to use for definition of relative speed in space of galaxy?

#### Soul Surfer

• Neilep Level Member
• Posts: 3345
• keep banging the rocks together
##### Re: can two objects travel away from eachother at more than the speed of light?
« Reply #2 on: 17/07/2012 08:37:19 »
Yes and no because the space time distortions cause by high speed travel mean that no one ever sees anything move faster than light.

See my earlier reply to the opposite case

http://www.thenakedscientists.com/forum/index.php?topic=44787.new#new

#### simplified

• Sr. Member
• Posts: 428
##### Re: can two objects travel away from eachother at more than the speed of light?
« Reply #3 on: 17/07/2012 09:55:42 »
Don't forget the stop of movements of the ships in points of destinations will show speed which considerably above than speed of light, especially if the ships will use indications of own clocks . :P

#### The Naked Scientists Forum

##### Re: can two objects travel away from eachother at more than the speed of light?
« Reply #3 on: 17/07/2012 09:55:42 »