to achieve this i used green screen footage of an asteroid flying through space, to get rid of the green i used the after effects plug-in Key-Light which allows you to use a pipet tool to click on the green which replaces it with the background alpha channel, to make sure the green was completely gone i switched to the screen matte view which shows the image in black and white, you can then use the screen matte clip white and black tool to increase the amount of white in the asteroid image until they are completely black and white. this then allowed me to place a JPEG image of space behind the asteroid after switching back to the final result in the view.
I repeated the steps for the next green screen where the asteroid crashes into the earth. I then added the Hard Rock Café logo and key-framed the opacity at the start of the image to midway through to create a fade in effect. after this I added the composition to the render queue and exported it. 