# How would be tv reception in a spaceship travelling close to speed of light?

My little brother has made me a tough question (specially for a computer science engineer).

Imagine that there is a spaceship orbiting earth close at nearly speed of light (say 99%). Someone in earth transmits a tv signal to spaceship.

What will the astronauts see in their television?

• Nothing?
• Accelerated version of what was recorded? (My best guess)
• Normal speed of what was recorded long time ago?
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The end result is that the observer on the Earth sees time moving slowly for the astronaut, while the astronaut sees time moving fast for the people on Earth. The factor by which time runs fast or slow is $\gamma$ where:
$$\gamma = \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}}$$
The factor $\gamma$ is greater than 1 for any non-zero velocity $v$ and it tends to infinity as $v$ tends to the speed of light. So if the Earth broadcasts a programme lasting 1 hour the spaceship will receive the whole broadcast in 1/$\gamma$ hours so the programme will appear to the astronauts to be speeded up.