Okay, so we know that Thor threw the hammer to the farthest end of the galaxy and it took mjolnir 60 seconds to go there and come back again. The milky way is about 100.000 light years across, so in 60 seconds the hammer traveled about 200.000 light years. So it went with about 3000 lightyears a second. Now in physics that's impossible until someone else discovers to be different, so the hammer kinda bent space o something in order to get there that fast. This being said, how much energy would a hit by the hammer produce if it impacted something, flying at 3000 lightyears per second? Thinking about this brings in mind debates like Thor vs Hulk, or Thor vs Superman. Would they even survive that hit?

You can't really bend space. You can't create or destroy energy and you can't add or take away from space or time.

Thor did not throw his hammer to the edge of galaxy and back in 60 seconds.

Thor actually wanted to commit suicide and knew the hammer would not be back in 60 seconds from the edge of the galaxy , however Odin interferes in the middle sending the hammer back before it reached the destination thereby saving Thor's life.

Your premise , therefore it flawed my dear friend.

I don't think he can throw the hammer that fast.

@alexandru84: 100,000 light years is referring one end of the galaxy to the other yes. But our solar system ( where Thor threw the hammer from) isn't on the edge of the galaxy, so it would be far less distance.