I'm posting on behalf of my friend - he could do it but I like doing the digging!
He took a time lapse while up in the Atacama and there were some odd faint trails in the photos.
Exposure 30
Aperture f/2.8
Focal Length 22 mm
ISO Speed 800
As far as I can see, they're too fast for anything astronomical apart from small meteorites but the tracks are wrong. Too fast to be planes, too wriggly to be satellites. #2 could be, I suppose.
I'd normally think faint reflections from land-based sources but he's in the desert. Mounted on tripod, no major vibrations nearby - but that would affect the other trails.
http://www.flickr.com/photos/bambi851/9541801961/(Flickr tag not working?)

Not expecting them to be anything spooky. Just curious to see if other timelapsers have encountered similar problems (if it can be called a problem, I suppose)
Ta