OK, you probably already know about the main plot. Some astronauts are flying to the sun aboard the spaceship Icarus II, in order to "restart" it with a "bomb". Exactly why the sun needs to be "restarted" or why a "bomb" would do it, is not explained. Nor is it explained why they need a manned mission in order to reach the sun. The film contains lots of beautiful pictures of the sun and the ship that adds nothing to the plot. None of the crew is really introduced to us properly, so we don't really care when they die.
17 minutes into the film they discover Icarus I circling the sun. The crew decides to investigate it, in order to bring the extra "payload" or "bomb", so they get two chances to "restart" the sun. This decision is of course fatal, but unfortunately for the film, not in any realistic way. It turns out that one of the crew-members of Icarus I is crazy and killed the old crew. After having survived alone for six years, he now continues his work by killing the crew of Icarus II. Gasp! could you find a more boring way of killing this movie? Apart from being crazy, he also lacks skin, and for some reason, every shot that contains him is blurry, either because they spent all their special effects money on pictures of the sun, or because the director was a big fan of the Blair Witch Project, and thought it was a good idea to recreate those fancy shaky-cam effects in a visually beautiful scifi-movie.
The crew also faces lots of other dangers, but they are all forced, unlikely incidents that would only happen in a bad movie. There's a faulty manual calculation that makes the "shield" point in the wrong direction, which damages a part of the ship, but no explanation for why the calculation needed to be done manually, or why the computer didn't correct it. There's a fire that starts for no reason, and a sprinkler system that fails for no reason as well. A computer that overheats because it doesn't shut down or go to power-save mode when cooling fails. I could go on, but you get my point...
Avoid this movie.