Astronomers on Earth measure a distant star to be eight light years away, and when they decide to send an astronaut to e

[answerhappygod]

Astronomers on Earth measure a distant star to be eight light
years away, and when they decide to send an astronaut to explore it
at nearly the speed of light, the astronaut has only aged two
years, while several years pass on earth. When they discuss the
time difference, the astronaut says that it is because of time
dilation, yet the astronomers say it must be due to length
contraction. Who is right?
a) the astronomers
b) the astronaut
c) neither, the reason lies in relativistic momentum
d) they are both correct, it’s the same phenomenon