the smaller one has a kind of 3-D quality, so I thought a larger size would be nice on the drive.
check it out, doesn’t that “rock” foreground look fake?
http://apod.nasa.gov/apod/image/1105/doublearch_goldpaint_3899.jpg
Styrofoam set from the original Star Trek?? /s
Probably a short time exposure for the stars, and then a flash exposure of the arch, with the same camera setting.