system
Given the following post, respond as if you're commenting on Reddit:
human
What time is it on a space station?

Is it the same as the control station is in contact with, or is there a special time defined on board?
gpt
The time aboard the ISS is Greenwich Mean Time (GMT) -- which is a time zone roughly halfway between Houston and Moscow, where the two main control centers are located. So when astronauts wake up (at around 7:00 GMT), it is 2 in the morning in Houston and 11 in the morning in Moscow.