Due, to know life on the moon there would be nothing to mess with the footprint, but the main reason why these footprints are going to last centuries is because "there is no weather." Since how there is no weather on the moon which means no wind there is no factors that could affect the footprint.
Hope this helps!
By studying a particular species .
Semipermeable means the cell membrane can pick and choose what goes out of it and into it. At least, that's what I believe it is.