How Can Amateurs Find Asteroids?

In a 1996 article titled “Hunting Asteroids,” you said a dedicated amateur could discover an asteroid on almost any night using a CCD-equipped 8-inch telescope. Is that still true today?

It was easier for backyard observers to discover asteroids a few years ago. Today, massive professional surveys such as LINEAR, NEAT,and LONEOS are sweeping the sky every clear night, all night. When I began hunting, the only survey was Spacewatch on Kitt Peak in Arizona, which covered just a small portion of the sky. When I wrote that article forthe Spring 1996 issue of the now-defunct CCD Astronomy, I figured the sky had been pretty much picked clean of new asteroids down to magnitude 16. Most of my discoveries were brighter than 18th magnitude. Today I would say most objects brighter than magnitude 18 have been found.

To be a real player in the discovery field now, you need to reach magnitude 19 or beyond. Fortunately, that’s still possible for backyard observers with CCD cameras, but now I’d recommend using an 11-or 12-inch telescope.

— Dennis di Cicco