Ed White is the first American space walker, which took place on Mercury 7. Sadly, he later died on the ground in the tragic Apollo 1 flash fire which took place during a test run. The accident took the lives of 3 astronauts before Apollo even got off the ground.
Note: I erroneously labeled this wallpaper as Mercury 7 and not Gemini 4. Image has been corrected.
Image Note: Some of the Earth image at the far left has been extended in Photoshop to fill out the space. The original image was square.