Notes from Thor’s astrophoto journal:

On April 8, a friend joined me to observe Hale-Bopp at my nearby and nearly-dark site at Lake Zumbra.  We enjoyed watching the very young moon set, then went about preparing to take some pictures. I was hoping to get a shot taken at a smaller lens aperture so the stars would have less distortion than in my earlier photos.

We were able to make three exposures of the comet.  Two of the three showed a tracking problem: the weight shifted across the drive gear during the exposure.  The result looked like a double exposure with every star appearing twice, once while the motor was “pushing” the gear, and again with the gear pulling the motor.  The separation is a measure of the backlash in the system.  Just another of the 1000 obstacles to taking pictures of the sky.

Fortunately, one frame turned out.  The stars are mostly quite sharp little points.  Their relative colors also show up nicely.  The comet itself has a broader dust tail than a week earlier; and the ion tail seems to have two parts!  Is this the “invisible third tail”?

The stars above Comet Hale-Bopp belong to the constellation Perseus.  Just to the right of the comet’s head is a tight grouping of stars.  This is M34, an open cluster, the 34th entry in the famous  Messier list of “non-comet” objects.

The lure of stargazing

Another common astrophotography hazard occurred to us: the bright headlights on the police car that came to check on us.  It seems to happen every few outings.  I had to explain to my friend that there are two types of cops: those that want to see your permit, and those that want to see Jupiter.  These were comet-viewing cops.

In spite of record-setting low temperatures, we took in a few other sights that night:.  We saw Mercury at about its highest possible position, the double cluster, the Orion Nebula (M42), the trapezium (the four stars that light it up), and we capped the evening off by inspecting Mars (complete with polar icecaps). 

So this photo carries with it the pleasant memories of an evening’s stargazing under clear skies with a friend to share the experience.