system
Given the following post, respond as if you're commenting on Reddit:
human
If an astronaut travel in a spaceship near the speed of light for one year. Because of the speed, the time inside the ship has only been one hour. How much cosmic radiation has the astronaut and the ship been bombarded? Is it one year or one hour?
gpt
You get the full year's worth of radiation.

From an outside point of view, we see that time is dilated and the astronaut is moving very slowly inside their spaceship. But we see the spaceship take a full year to reach its destination, and gets hit by all this radiation along the way.

From the astronaut's point of view, there is another effect - length contraction. From their point of view, the reason it only takes an hour to reach the destination is because the distance has shrunk down by a huge amount. So, from the astronaut's point of view, they still have to move through the same amount of "stuff" - interstellar gas, radiation, whatever - it's just that this "stuff" is packed really close together, and the astronaut hits it all really quickly.

Of course, it's not all that simple - you have to deal with redshift and all that - but it does often work out that length contraction and time dilation basically cancel out, and that can allow different reference frames to not contradict each other.