1)If the light transmitted from our earth need 4 days to reached Mars.
2)A space crew that observe at the earth from mars will have a 4 days delay.(the image of earth he see r 4 days ago,due to light transmitted from earth need 4 days to reached Mars)
3)When a spacecraft travel to Mars in speed of light,the image of our earth tat the spacecrew will c will remain the same/non changing,or wat we said time stopped.
4)But when a spacecraft travel to Mars in a speed tat exceed light speed,the spacecrew will notice things on earth will be moving in backward/like reverse mode on movie,or should i say going back to the past?
5)On the opposite,a spacecraft tat travel back to earth from Mars in light speed/close to light speed,will notice things on earth moving in fastmotion/like fastforward mode in movie,so travel to the future?
6)By the time the spacecraft reached earth,the spacecrew will notice the earth is totally 8 days different from wat he seen from Mars.(the image of earth he c on mars is 4 days ago,when he travel back to earth he need 4 days too even in lightspeed,so 4+4=8 )

Btw,communication signal r not any faster than lightspeed,if we send an email to Mars,the email will need 4 days to reached mars.

if we have the technology to bring one of our (telescope+a video recorder+a crew on it to press the record button) to a faraway place tat r million lightyear away,we might be able record down how dinosaur extinct

This post has been edited by Louiz87: Jan 16 2010, 04:50 PM