KMC Forums - Lookin' for movie name

I'm obviously new here. Hoping somebody...ANYBODY can help me with this movie:

I believe it's from the 60's. Black and white. It's about a ship/rocket that gets hit off course and orbits the earth between 1 and 5 miles above the earth. The heat generated from this ship burns everything underneath it's path and it begins to destroy the earth as it orbits. Scientist come up with an idea to blast it away with a atomic bomb. Of course rioting and such is going on and on the way to the launch pad a group of young thugs ambush the rocket containing the atomic bomb and open it...all of course dying. The main character though manages to put the bomb back together and shoots down the ship in turn himself dying and saving earth. I keep thinking it's called "5 miles up" but i'm probablly wrong. Anyone out there ever heard of this? Any suggestions on where to go to find someone with knowledge of this movie?

Thanks in advance,
embarrasment