Observing Report: Messier Marathon!February 14, 2010
My parents got me Harvard Pennington’s The Year-Round Messier Marathon Field Guide this past Christmas, and I have been obsessed with Messier Marathons ever since. I’d never run one; before last night I’d seen fewer than half of the Messier objects (54/110).
(A Messier Marathon is an attempt to see as many of the 110 Messier objects as possible in one night. Although Messier’s list has been around since the late 1700s, no one had realized that it was possible to see all of the objects in one night until the 1970s, and no one succeeded in getting all 110 in one night until 1985. Loads more info here.)
Pennington subverts a lot of conventional wisdom in the book. Before reading the book, I figured I might attempt a marathon some day after I’d seen all the Messiers and knew my way around the sky a little better. Pennington argues forcefully that running a marathon is the best way to learn the sky, build observing skills, and build confidence. In other words, it’s not something you have to work up to, it’s the way you work up to a good working knowledge of the sky.
Also, before reading the book I’d only heard of people attempting marathons in March and April when it’s possible to get all 110 objects. In Pennington’s words (page 3):
Some people go Marathoning only in March…. That is silly. The very next dark of the moon is the best time for you to run your first Messier Marathon.
One of my local clubs, the Pomona Valley Amateur Astronomers, was heading to Death Valley for a big star party this weekend. For various reasons, I was looking for something a little closer to home. Last month the PVAA star party was down at the Salton Sea, but we got clouded out after just a couple of hours. I knew that fellow PVAA member Ken Crowder was also looking for a closer spot and thinking of returning to the Salton Sea, and we planned to meet there yesterday evening. Ken was going primarily for astrophotography, and I was going to attempt a Messier Marathon.
Pennington’s Field Guide was my inspiration and how-to guide. I also wanted an all-sky map showing all of the Messiers that I could use as a roadmap. I found this one on WikiMedia Commons and printed out a color copy on 11×17 paper.* Finally, I used Stellarium to figure out where the horizon would be at sunset and sunrise, to determine which Messiers would be easy, which ones tricky at dusk and dawn, and which ones impossible. I used a black marker to draw the horizon lines on my all-sky printout, and used the marked-up map to figure out a search sequence.
In this I departed a bit from the Field Guide, which has built-in search sequences for every month of the year. These are good and helpful, but in places counterintuitive. Search sequences are critical for catching those objects that are only visible in short windows at dawn and dusk. For the rest of the night, it makes sense to work from west to east in strips and from south to north within a strip (because more southerly objects set sooner than northerly objects at the same right ascension, or sky “longitude”), but the exact order is less important. My decision to depart from the Field Guide sequence was not without consequence.
Strategies for Starting and Finishing
For the twilight rush, I wanted to start with M39, an open cluster near the bright star Deneb in Cygnus. It was the lowest Messier object in the sky at sunset, and thus the hardest to pick out of the twilight glow before it set. I wasn’t too worried about getting M39, because it’s fairly far north and would rise again a couple of hours before dawn. Still, it would be nice to get off to a strong start by picking it up the first time.
After M39, the twilight rush was full of galaxies: M74, M77, the Andromeda galaxy (M31) and its bright satellite galaxies M32 and M110, and fellow Local Group member M33. I was worried about these because galaxies are notoriously difficult in bright skies, and I’d never seen half of them, including the crucial M74 and M77.
At the other end of the night, I was anxious to see how many of the clusters and nebulae I’d be able to fish out of the sky around Sagittarius. This was a special concern because the area around Sagittarius and Ophiuchus holds the densest concentration of Messier objects in the sky–almost a third of the Messiers, in a patch of sky about as big as two outstretched hands. On top of that, they’d be rising just before sunrise. At best, I’d go into the Sagittarius region with 70-odd objects logged; the outcome of the marathon would largely depend on how well I fared that area, at the end of an all-night observing session, racing against the sunrise.
I knew from Stellarium that at least four objects were flatly impossible, because they would never be above the horizon without the sun: M72, M73, M30, and M2. Three more were pretty iffy; M55, M75, and M15 would be flirting with the horizon but deep in the morning twilight. A final three I felt pretty good about; M54, M69, and M70 are at the bottom of the Sagittarius “teapot” and I thought they’d be tough but doable. All told I figured the maximum possible outcome would be 100 objects definitely, 103 probably, and 106 at the very outside.
Setting Up and Getting Going
I got down to the Salton Sea just before sunset and found Ken set up in a parking lot near the campground. I set out my 6-inch Dob and 15×70 binoculars. I’m working on the Astronomical League’s Messier and Binocular Messier observing programs, and I wanted to bag as many Messiers as possible with both instruments (please be aware that the AL does not accept marathon observations for the Messier Club; nevertheless, running a marathon is still good practice and makes finishing the AL observations easier). I also brought a folding chair for seated observing at the scope, a tray table for maps and charts, a camp chair for visitors (which ended up holding the binoculars between looks), and a tripod for the binoculars. Normally I prefer to use the binoculars freehand, and in fact that is how I used them for most of the night, but when searching for tough stuff in the twilight it’s nice to be able to point them in one place and have them stay. I also brought along the basic creature comforts: warm clothing, snacks, and plenty to drink, both water to stay hydrated and energy drinks to stay awake.
The evening rush turned out to be surprisingly easy. M39 was an easy catch in both binos and scope. I couldn’t get M74 in the binos but it was fairly easy in the scope with averted vision. On the flip side, M33–a big, dim, face-on spiral galaxy–was easy prey for the binos and I didn’t try for it with the scope. In retrospect, I think I should have at least tried, but at the time I didn’t want to take any time out of the evening rush for such a notoriously tough catch.
Soon I settled into a rhythm. I used the all-sky map to figure out what to hit next and the Pocket Sky Atlas to figure out how to get there.** I tended to seek isolated targets with the binoculars first and then the scope. For objects in clusters or chains, I needed to be able to leave an instrument on a landmark I could get back to, so I worked out the star-hops with the scope and then chased them up in the binos.
The Realm of the Galaxies
Heading into the marathon, I was sweating the Virgo-Coma Cluster more than Sagittarius, for two reasons. I’d been through most of Sagittarius before, and it’s almost all globular clusters, which are usually easy. Virgo and Coma only have about half as many Messiers as the Sagittarius/Ophiuchus area, but they’re ALL galaxies, very tightly packed and with few bright stars for finding one’s way. Both the Field Guide and the Pocket Sky Atlas have special charts just for the Virgo-Coma “clutter”.
It turned out to be surprisingly nonproblematic. Perhaps it’s because I’ve been doing so many star-hops with binoculars from my driveway, but under the reasonably dark skies at the Salton Sea I found enough stars to guide me through the clutter. It wasn’t fast or fun–including 15 minutes off for a snack and a bathroom break, it took me almost an hour and a half to track down the 16 galaxies in that part of the sky–but I got them all. And all but one with the binoculars, after having found my path with the scope.
In any Messier Marathon in or around March, there is a spot after the Virgo-Coma Cluster when you’ve seen everything that’s above the horizon, and you might as well knock off for an hour or two while you wait for Ophiuchus and Sagittarius to crawl over the eastern horizon. In the quarter hour leading up to 2:00 AM I fished M12, M10, and M107 out of the dense atmosphere near the horizon, and then decided to call it for a while. I packed everything up and crawled into the car for a nap.
I couldn’t sleep until I had double-checked that I was on track, so I pulled out the all-sky map and started checking off targets based on my log. I had 73 down, but try as I might I could not find more than 36 unseen targets on the map. Somewhere I had missed something. And I had a nagging feeling that the one I had missed was one of Messier’s “mistakes”–a multiple star rather than a cluster. Fortunately, the Field Guide breaks down all of the Messiers by type and includes a special section on these. And there it was, M40, a double star in Ursa Major. I had completely missed it while sweeping up the Great Bear’s galaxies in the early evening. Fortunately it would be high in the sky for the rest of the night so I’d get another shot, but it illustrates the risk of not sticking to a strict, written observing program (M40 was on my map, I’d just cruised right past it).
Sorting that out took the better part of an hour. I planned to get back at it at 4:00. I set my alarm, closed my eyes, and…failed to sleep. Too keyed up, too anxious about Sagittarius. But I did rest.
I got a bit of a late start. After rousing at 4:00, taking a biology break, and re-setting up all of my gear, I didn’t cross off M40 until 4:22. Then I knocked out M57, M56, M29, M27, and M71 in the area around Lyra and Cygnus–the last five objects outside of the Sagittarius snarl. I was back in the groove and went into Ophiuchus and Sagittarius crossing off an object every three minutes.
It wasn’t enough.
Having never seen a sunrise at the Salton Sea–and having seen only a couple of sunrises from any observing field–I had tried to guesstimate how late I could go from Stellarium. I knew the sun would come up at 6:40 AM, and I figured I could push through to about 6:00. Imagine my distress when at 5:20 I saw the sky getting bright in the east. I trucked on through the “steam” rising from the Sagittarius teapot, but I was getting desperate. Shooting up to Scutum and the “tail” of Aquila, the Eagle, I could not find M26 in the brightening sky. My final object was M11, the Wild Duck Cluster, which was an easy catch in binoculars at 5:38. I wanted to get it in the scope, too, but with so few stars showing in the sky I couldn’t figure out how to get there. I finally had to start at the other end of the Eagle, with Altair, and hop down the bright stars of the backbone. I got to the right spot, and couldn’t see a thing in the low power eyepiece. I had to boost the magnification to 120x to darken the sky sufficiently to pick up the dim outlines of the cluster, finally bagging it at 5:44. And that was it.
I am pretty certain now that M55, M75, and M15 were too far down to be possible. I still think that M54, M69, and M70 might have been possible at the base of the teapot, but by the time I got to them they were history. I missed M26 and later realized that I’d passed by M23 in my Sagittarius blitz.
I ended the night with 98 objects. I got M74, M109, and M98 in the scope only, M33 in the binoculars only, and the other 94 with both instruments. I also wrote down a one-line description of each object. As stated above, marathon observations don’t count for the Messier Club, but it was still useful to scribble down a brief description. It will make re-observing the objects easier and more interesting, since I’ll be able to compare my thoughts from a more leisurely look to my brief impressions on marathon night. And it is nice to have a physical memento of the night; I’ve reread my notes a couple of times already and have a feeling that I’ll return to them a lot in the future.
On one hand, I am frustrated that I ran out of time. M23 and M26 should have been easy prey–they were way up in the sky compared to some of the other home-stretch targets–I just never got to them. A rookie mistake, fairly small in the big scheme of things, but it kept me from that magical three-digit number.
On the other hand, 98 objects is still a great score for my first marathon, especially an “off season” marathon in which fewer than 110 objects were possible to begin with. It was a huge confidence builder and a heck of a lot of fun. I learned a ton about what works and what to avoid. And I’ll definitely be back for more.
* The printable version of this chart is now on the “Messier Marathon tools” page on the sidebar, along with a streamlined checklist for marathon night and other goodies.
** It occurred to me after I wrote this that it might sound a little odd. On one hand, I have been singing the praises of the Year-Round Messier Marathon Field Guide, which includes both a search sequence and charts for each object. On the other hand, I used a free star map to figure out my sequence and the Pocket Sky Atlas for actual finding. So you may be wondering if I used the Field Guide from the field at all.
The answer is that frankly I didn’t use it that much. The Field Guide charts are great, especially for people who don’t have an all-sky atlas or who are looking for one-stop shopping for the Messiers. But from working on the AL Binocular Deep Sky and Urban Observing lists this spring I’ve gotten used to using the trio of (1) an observing list, (2) the PSA, and (3) a logbook for taking notes. I have used the Field Guide once or twice in the field, but I’m so used to the PSA now that it just feels more reflexive to reach for that instead. And I knew that on marathon night I needed to use what worked best for me.
That said, I did use the Field Guide to find the one that I’d missed (M40), to double-check that I’d gotten everything in the Virgo-Coma clutter (even though I used the PSA for the actual slog), and to work out a couple of the twilight rush star-hops. The Field Guide was most important for giving me the inspiration and confidence to tackle a marathon in the first place, and I definitely wouldn’t have been without it by my side. It’s a great book and I recommend it to anyone with an interest in deep sky observing.