Robert Stephens

Over the years, I have done many facets of amateur astronomy including visual observing, film photography, CCD imaging, variable star observing, and occultation and graze timings.  In recent years, I have developed an interest in asteroid research including astrometry - the recording of positions to determine orbits; and photometry - the recording of brightness to determine rotational periods and other attributes.

 

What got me started in asteroid work is an article written by Dennis di Cicco of Sky and Telescope magazine on just how easy this is to do from the city. Dennis related that fact that he could make new discoveries every night.  Things have changed since that article was written several years ago. With the alarming realization that Near Earth Asteroids pass close to the Earth on a regular basis, several professional search programs have come on line in order to identify all of these close asteroids over the next ten years.  These automated professional programs regularly sweep the sky on every clear night and have found most of the brighter asteroids that amateur astronomers are able to find with their smaller equipment. Now, unless you are away from city lights and/or operate a larger telescope, you are not likely to find any 'New' asteroids (I say that knowing that amateurs still find new asteroids every day).

 

However, there is more work than ever to be done. There are now tens of thousands of numbered asteroids, those with a well-known orbit. Rotational periods have only been determined for about a thousand or so of these asteroids. More information can be found at the Collaborative Asteroid Lightcurve Link (CALL) maintained by Brian Warner.

 

I subscribe to the Minor Planet Mailing List which gives a lot of good ongoing information on the subject of measuring asteroids. A workshop on photometry (which I am on the organizing committee) is hosted by the Society for Astronomical Sciences.

I am a member of the AAVSO and occasionally I do work on variable stars.  These are typically found in the field of view of some asteroid I was working, and I feel obligated to try to resolve some basic features.  In addition, I will work on special projects such as transiting extro-solar planets.

Photometry