Here's my gallery of asteroids captured in Stardial images. It's a challenge to see how faint a moving object can be detected in this way.
No asteroid test would be complete without finding Ceres. Asteroid #1, the big one. It's not the brightest asteroid, though. But here it is, tracking through the RA 0030 images, Dec 2002 to Jan 2003:
Here's 13 Melpomene cruising through the RA 0000 images in Sep 2002:
These two images are a good example of what to look for. This is about how far a main asteroid belt object will move per day. But the trick is to find fainter objects, so ... here's an asteroid at about magnitude 11:
This is 41 Daphne, about mag 10.9, from Jan 22-24, 2003 on RA 0900 plates. If you have a hard time spotting it on the left-hand picture, look at the right-hand one, where I subtracted a "standard" frame. Poof! The standard frame wiped out all the usual stuff, leaving just the changed objects behind. Now I'm tracking Daphne as it makes its way across the sky ...
Kinda hard to see, let's zoom in a little ...
Still tough -- how about an animated version?
Anyway you look at it, this is not an easy item to spot. It's near the limit of what the Stardial plates can capture. Still, there are a lot of objects in this range, and who knows when a new one will come along?