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Update for 2021



Messier Marathon

Charles Messier was the 18th century "ferret of comets" who compiled the now-famous catalog that totals about 110 objects. Some final additions were made by 20th century researchers, and there's still contention about the identity of M102 and the inclusion M110. Ironically, Messier's primary intention was to tabulate these now-treasured objects so they could be avoided as distractions from the primary pursuit of finding comets.

Astronomically, March is the best time of the year for a Messier Marathon in the northern hemisphere (although March weather in New Jersey can be a problem). In brief, the basic concept is to spot all of the objects on the list during a single night, although variations have been devised that may call for multiple nights, doing it with a limited instrument (such as binoculars) to make it more difficult, or for advanced observers, doing it from memory alone.

My best Marathon was in 2010, when new moon was on Monday, March 15th at 5:01 pm EDT (goodness, a decade ago). Since the weather forecast was excellent for Wednesday night, March 17-18th, I made a Marathon run at Coyle Field in New Jersey. A total of 103 Messier objects were found along with two comets; here's a tabulation. I failed to find M74 in the evening because it was low in the west, and too dim against residual twilight and the Philadelphia light dome towards that direction. In the morning, I failed to find M2, M30, M55, M72, M73 and M75 because I "ran out of gas" around 5:15 am. M30 was probably the only morning object that wasn't achievable had I persisted for another half-an-hour or so (it simply rises too late in mid-March). There's also an hour span starting shortly after midnight when I didn't find anything. That's because I was caught up with the available Messier objects and was waiting for the next ones to rise a bit higher, so I decided to look for Omega Centauri, which would transit at a few degrees altitude. The latter effort was unsuccessful, mainly because due south at Coyle Field is towards Atlantic City, NJ, and its light dome. However, Coyle's low horizon's were otherwise ideal for the Marathon. Sadly it's no longer accessible to observers, and it won't be in the future (here's a page covering my last session there on the night of April 5/6, 2016).


The 12.5" f/5, split-tube  Discovery Dob used for the 2010 Messier Marathon, shown at Coyle Field on October 7, 2015 (click the image for a larger version). As seen here, as well as for the 2010 Marathon, the scope is strictly manual. The only pointing aid is a Rigel QuikFinder reflex type, which projects a red bull's-eye on the sky (concentric circles, 0.5 and 2.0 diameter). It's the small, elongated box jutting from the upper-left of the tube.

For the 2021 Marathon, new moon is on Saturday, March 13 at 5:21 am EST, so for most folks, the nights of Friday/Saturday, March 12/13, or Saturday/Sunday, March 13/14, will be the preferred nights. Note that Daylight Savings Time begins on Sunday morning, March 14, at 2 am EST when clocks jump ahead to 3 am EDT. Regardless, feel free to pick another night as one's schedule and the weather dictate. New moon is close to mid-month for this year's Marathon, so M74 in the evening will have the usual difficulty and M30 will be well-nigh impossible in morning twilight from our 40N latitude (it rises about 5:30 am EST on March 13, roughly 40 minutes before sunrise, so relatively bright twilight will interfere significantly). The next new moon will be on Sunday, April 11 at 10:31 pm EDT. Postponing a month would make the initial evening objects more difficult, but M30 becomes a possibility, rising almost two hours before sunrise.

As homage to Charles Messier, I try to include one or more comets when doing the Marathon, if possible, but so far in 2021 (as of this writing on February 17) there are no reasonably bright comets to recommend. There's always the chance that a bright new comet will appear before then (hope springs eternal for comet observers). If any such comet does appear, I'll post a note here. In the meantime, check COBS (the Comet Observation Database) for the latest comet information.

I've prepared a print-ready, blank PDF log sheet based on Harvard Pennington's sequence from his book, The Year-Round Messier Marathon Field Guide, which is not only an excellent primer on the Messier Marathon itself, but also on the use of the geometric method for easily finding the objects manually. It's useful not just for the Marathon, but any time of the year searching for Messier objects, and ultimately, the method can be applied to any celestial object. The log sheet can also be used any time of the year. The sequence won't change, but the starting point will, and a changing block of objects will not be visible depending on the position of the sun. Unfortunately, the publisher, Willmann-Bell, ceased operation in 2020.

While the sequence on the log provides a sensible plan of attack based on setting times in the beginning and then rise times later on, it needn't be followed slavishly. Note that on my 2010 log, eleven objects were seen out-of-order before the end of astronomical twilight by taking advantage of them being relatively bright. I've also discovered that when there's trouble finding a given object, don't linger too long on it. Instead, move on to the next object or two, then come back a little later after clearing one's mind of the difficult object.

Finally, with the ongoing restrictions due to the COVID-19 pandemic, it may be difficult to find an available dark site this year. Good luck!

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