When attending their first meeting with the Texas Astronomical Society of Dallas several years ago, Victoria Catlett heard the word “marathon” in a list of upcoming events. Catlett, who was a college student at the time, immediately envisioned running.

“I thought it was an actual marathon,” Catlett says. “And I was like, ‘What? Why would I want to do that?’”

Though the Texas astronomers had no intention of racing 26.2 miles, they were planning an event that also takes dedication, the proper pacing and a good bit of endurance. Called the Messier marathon, it’s a skywatching challenge that prompts astronomers to spot all 110 galaxies, nebulas and star clusters in the Messier catalog, a list of objects started by 18th-century French astronomer Charles Messier—and to find them in a single night.

In 1758, Messier was looking at a newly discovered comet when he became sidetracked by a fuzzy-looking blob. At first, he thought his distraction might be Halley’s Comet, but it turned out to be the Crab Nebula, a supernova remnant in the constellation Taurus. Determined to alert other astronomers to deep-sky objects that could easily be confused with comets, he began a list, leading with the Crab Nebula, which he termed M1. By his death in 1817, Messier had compiled 103 objects into his catalog. Other astronomers later revised the list based on Messier’s notes and brought its total to 110, adding to the catalog six new galaxies and a star cluster.

a spiral galaxy viewed edge-on looks like a glowing disk with an orb of light rising above and below it
The Sombrero galaxy (M104) earns its name from its resemblance to a wide-brimmed Mexican hat. This was the first object to be added to the Messier catalog after Charles Messier’s death. NASA and The Hubble Heritage Team (STScI / AURA)

Origins of the marathon

Centuries after Messier started his work, in the mid-1970s, a few amateur astronomers began to envision a challenge based on his records. In a suburb of Pittsburgh, Tom Reiland stopped by the home of fellow amateur astronomer Tom Hoffelder after a night of observing. Reiland said he believed it was possible to find every one of the Messier objects in a single night, if they timed it correctly. Hoffelder said he’d been thinking the same thing.

In the following years, they waited for the right moment to give it a try. Then, independently, each made a marathon attempt. At the same time, Don Machholz, an amateur astronomer who discovered 12 comets in his life, also independently came up with the idea. In 1985, amateur astronomer Gerry Rattley of Arizona became the first person on record to successfully complete a full Messier marathon.

“I didn’t expect it to be that big of a thing, when we came up with it,” says Reiland, a now-retired senior observer at the Allegheny Observatory in Pittsburgh. “It was just one of those things that you want to challenge yourself and see how good you are—and to what limits you can go.”

Now, local astronomy clubs across the country host Messier marathon nights, and Catlett has participated in two with the astronomers in Texas. Afterward, the group recognized some of its top observers with an awards ceremony. “I don’t know if it’s something you really put on a resume, but you can brag about it to other amateur astronomers, and they’ll know the significance,” says Catlett, who is now a software engineer at West Virginia’s Green Bank Observatory.

a dense collection of stars and cosmic dust
One of the more unusual Messier objects is the Sagittarius Star Cloud (M24), which includes stars near the heart of the Milky Way. Stephen Rahn via Flickr, public domain

A Messier marathon can be completed at any time of year, but to have a chance at spotting all 110 objects in the catalog, observers typically must head outside in March or early April. Even then, they’ll have to time it right—the sky must be clear all night long, and light pollution needs to be at a minimum. For many astronomers, that means they attempt their marathon as close to the March new moon as possible, when the night sky is at its darkest. This year, that happens on March 10, with a secondary window for the marathon on April 6 and 7, creating prime conditions for spotting the most objects.

Reiland’s record is 109 Messier objects on March 15 and 16, 1980, over the course of nine hours in the southwest corner of Pennsylvania. (At that time of year, one of the objects could not be seen at his latitude.)

Amateur astronomer Ted Forte spotted about 70 objects during his first marathon, which he did from his former home in Virginia in 1994. One time, he participated in what was billed as an “extreme” Messier marathon in Coinjock, North Carolina. “Not only did you have to find the objects yourself, you couldn’t use a map or a list,” he says. “You had to do it all by memory.” That night, he found 50 objects.

Others go about the marathon in similarly intense ways—Catlett knows one astronomer who has spotted nearly all the Messier objects in a single night using binoculars. With lower magnification than a telescope, binoculars resolve many of the objects only as hard-to-identify smudges, and the observer can lose track of a galaxy with an accidental shake of their hands.

Many people use telescopes with built-in tracking that can automatically point to an object when you type in its name. But for an official, by-the-book Messier marathon, you have to find the objects without a computer’s aid.

“If the computer’s not tracking, then getting all of them in one night is very impressive,” Catlett says. “You do have to know where they are already on the sky and be able to find them when you’re super zoomed in [with a telescope].”

‘Running’ a Messier marathon

pink, orange and green wisps of gas with some bright blue stars scattered around
The Orion Nebula (M42) is a stellar nursery that can be seen with the naked eye below the characteristic three-star belt of Orion. NASA, ESA, M. Robberto (Space Telescope Science Institute / ESA) and the Hubble Space Telescope Orion Treasury Project Team

Those who want to round up all 110 objects in a single night arrive at their observation site early. Astronomers set up their telescopes before sunset, and as night begins to fall, the serious skywatchers get started. The first 20 minutes or so are “kind of a rush,” Forte says. Certain objects will set quickly, so there’s only a limited window to find them. And this can really be the hardest part—with the last rays of sunlight still present in the sky, these objects will appear very dim.

From here, the strategy is systematic—moving west to east and south to north, astronomers point their telescopes through a sequence of cosmic wonders. They’ll observe the objects that lie in close proximity to each other, at least from our point of view, jumping from one to another in a technique called “star hopping.” For instance, instead of pointing a telescope at the area of sky with the Dumbbell Nebula (M27) and hoping it appears in the instrument’s incredibly narrow field of view, astronomers might begin with viewing the bright star Altair, then “hop” toward the nebula across dimmer stars and the constellation Sagitta.

Sometimes, viewing nearby objects is a helpful trick—but at other times, it can be a headache. Take the Virgo Cluster, the nearest and best-studied group of galaxies, which forms an irregularly shaped clump in the constellation Virgo. In this region of space—no larger than the area that would be covered by your fist, held at arm’s length—lie roughly 2,000 galaxies. And only 16 of them are Messier objects. This makes the cluster one of the most difficult areas of sky to navigate, but careful star hopping and growing familiar with the galaxies can make the task less intimidating.

a collection of yellow galaxies that appear as fuzzy yellow orbs and ellipses
The Virgo Galaxy Cluster, taken with the Burrell Schmidt Telescope in Arizona. The largest galaxy, at the lower left, is the elliptical M87, and the dark circles are areas where bright stars were removed from the foreground. Chris Mihos (Case Western Reserve University) / ESO

Early in the night, astronomers will view the dim and elusive Triangulum Galaxy (M33)—followed closely by the Andromeda Galaxy (M31), our nearest galactic neighbor. Crowd favorites like the Orion Nebula (M42), located in the sword of the celestial hunter, and the Pleiades Star Cluster (M45), which gives the automaker Subaru its name and logo, will come soon after. The hobbyists are more relaxed now and might move around, chat with friends or let newer astronomers look through their telescopes.

But at a certain point, often around 1 in the morning, comes a lull in the marathon. For those who have kept pace with the recommended timeline, it will now be at least an hour before the next objects rise. Some call it quits, pack up and head home; others might go in for a break, then end up falling asleep. But an intrepid group will keep at it, maybe fueled by snacks and some hot coffee. By these early morning hours, the winter chill has really set in.

Forte recalls doing an organized marathon on an especially cold night in Suffolk, Virginia, with his son, who was a teenager at the time. A local news reporter approached them and talked to Forte’s son around 2:30 a.m. “The quote she got from him was, ‘I can’t feel my feet,’” he says.

a grouping of blue and yellow stars loosely clustered together
The Beehive Cluster (M44) is a collection of stars located in the constellation Cancer that gets its name from its resemblance to a swarm of bees. Fried Lauterbach via Wikimedia Commons under CC BY-SA 4.0

Around the end of the night, after clocking objects like the spectacular Ring Nebula (M57) and the quirky Wild Duck Cluster (M11), named for the rough V-shape of its bright stars that resembles migrating birds, astronomers turn to the constellation Sagittarius, a mother lode for marathoners. The celestial centaur contains a whopping 15 Messier objects, mostly star clusters and a few brilliant nebulas.

If astronomers have successfully stayed on pace, they might find themselves near the end of their marathon with only one object to go: M30, a globular star cluster in the Capricornus constellation. With the minutes until dawn ticking down, they’ll look toward the eastern horizon and hope to catch a glimpse of the swarm of stars before the sun emerges and the next day begins.

Engaging the public with the night sky

While the Messier marathon is a way for veteran astronomers to test their mettle, it has a low barrier to entry. Observing any group of Messier objects in a single night can count as a marathon, even if it’s only a few. And the group marathons hosted by local astronomy clubs in March are friendly to newcomers.

“I think it’s a great way to get new people involved in astronomy,” Catlett says. Usually, public observing sessions might focus on objects closer to home, like Saturn or Jupiter and its moons. “But this is a way to give people a little more insight into all the stuff that’s out there. … It really helps people get more of a connection to outer space.”

And for someone just learning their way around a telescope, finding Messier objects is a rewarding way to build technical skills. Being able to navigate to a galaxy, nebula or cluster against the vast expanse of space brings “a sense of real accomplishment,” Forte says. “When you finally do that, especially if it took you a long time, it’s kind of an incredible feeling.”

a yellow elliptical galaxy appears as a fuzzy blur in front of other galaxies and stars in the distance
This dwarf elliptical galaxy is M110, the final object in the Messier catalog. KPNO / NOIRLab / NSF / AURA / Adam Block

Nearly half a century after the first Messier marathons, amateur astronomers are still looking up, gathering under dark skies and counting—with luck—to 110. Something about this enduring contest has managed to keep drawing astronomers in, decade after decade.

For some, maybe it’s the physical challenge of staying awake all night and the mental test of spotting the objects. “Maybe there are a lot of people, like myself, that are a little bit on the crazy side,” Reiland says. “We like doing things like that.”

Or maybe the draw is something much more fundamental, tapping into an age-old interest in the stars and the deeply human wonder about the cosmos.

“For me, there’s nothing like a good, clear night with good optics, and maybe having a few friends around with you, enjoying the night sky,” Reiland says. “It’s just something that takes your mind off of everything else.”

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