Messier Marathon 2009

The Messier Marathon seems like a silly exercise, but it’s certainly fun. Jane and I were introduced to our favorite dark sky desert observing site five years ago when Don Machholz invited us to join him for a mid-week Messier Marathon.

Big dobs set up for the Messier Marathon under clear steady blue skies.

We’ve logged 108 and 109 of the 110 objects a couple of times, but this year looked like it could be our best opportunity to log all 110 objects in one evening. The Desert Center Clear Sky Clock along with the NOAA forecasts offered a clear dark transparent sky all evening with excellent seeing — a rare combination.

The most challenging early twilight objects are difficult, but our site is far enough south, with good western horizons, that Jane and I were just able to detect M77 and M74 before they set. With those in the bag, a 110 night seemed like a sure thing. This late in the month, M30 should rise well enough before dawn that we’ll be able to see it.

I was armed with a stack of custom charts from Skytools 2 for my 14.5-inch dob, and Rob Hawley’s Messier Marathon guide. Jane was working from a similar stack of Skytools charts that I’d made two years earlier — luckily none of the Messier objects had moved in that time.

Stacks of charts and checklists ready for the marathon.

The Virgo galaxy cluster is probably the most challenging mid-evening observing puzzle. It’s easy to get lost in the broad stretch of sky with hundreds of galaxies and a seeming dearth of guide stars. Finding galaxies isn’t the difficulty, it’s identifying which is which.

Most MM guides recommend an eyepiece-based star/galaxy hop that moves from a major guide star to each of the target galaxies in step. I’ve used this technique successfully in the past, but this night it didn’t work out.  I think the galaxy-hop is optimal for a smaller telescope with about 50x power and a 2-degree field of view. This helps keep you from getting lost by showing more context and fewer faint galaxies.

I fell back on my individual Skytools finder charts, and was able to finish all of the Virgo objects. After bagging southerly M83 at about 11:00 p.m., I tucked into a sleeping bag and set my cell phone alarm for 2:00 a.m.

(Click for full size) Example individual Skytools chart from my session, showing naked eye with Telrad circle, finder view, and eyepiece view, all customized for my finder, telescope, and eyepiece. On each chart I write the observation time and any notes with a Sharpie.

When the ringing phone woke me, I looked out of the van to see what looked like a milky sky. “That can’t be!” I thought. I could still see a few stars, maybe it was just a trick of my dark adaptation.

The morning sky at our desert observing site.

Jane was still at it when I stumbled out of the van to give me the bad news. There were still enough sucker holes for me to nab the Ophiucus clusters, but by the time I finished the Ring Nebula the sky was completely gone. This picture of the pre-dawn sky shows what it was like.

I finished the night with 76 objects logged. Jane managed to log 82, stealing clear sky opportunities while I slept. All in all, we had a great night in the desert, and the clouds forced us to get a little extra sleep.

My favorite neglected object from the list: M47 with its little embedded planetary nebula.