Why are the arms of spiral galaxies typically blue in color?

Is it possible to use the energy from two atoms colliding to create a clean burning lasting fuel source with a large amount of force? is it also possible to harness that energy from the two atoms colliding to create a clean energy source that will last for years from just two atoms colliding. is there a possibility to control and store that energy for years but slowly let the energy out enough to power cities cheaper and faster.

Which feature indicates that mars resides in the inner region of the solar system

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.