2024-03-29

South Plains Astronomy Club

Observing Under The Dark West Texas Skies

Every spring, amateur astronomers gather to hunt down the 110 items in Charles Messier's catalog all in one night. This star-hop challenge is a fun social time for us to test our navigation skills. This article provides some basic info on the marathon, advice to make your adventure fun, and a bunch of links to help you succeed.
Ansiaux (1729—1786) (??), Public domain, via Wikimedia Commons

Charles Messier (1730-1817) was a French astronomer and comet hunter. He discovered 13 comets between 1760 and 1785.

To make his task of finding comets easier, he made a list of objects that could be mistaken for comets in the primitive telescopes of the day which are roughly equivalent to the light gathering power of a cheap 60mm department store telescope of today!

Fortunately for us, Messier’s list is also a list of bright deep space objects for amateur astronomers

The Messier catalog

The Messier catalog includes galaxies, globular clusters, open clusters, nebulae, a super nova remnant, an asterism, a double star, and one patch of the Milky Way. Messier was the first to catalog seventeen of the objects in his list. The objects are all visible from Paris (the same latitude as Ottawa) and range from the north pole to -36º, so the catalog misses many stunning objects in the southern hemisphere.

Michael A. Phillips, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons

In the 1970’s, the Messier Marathon was invented by a trio of American amateur astronomers. A marathon is an effort to view all of the Messier catalog in a single night. The purpose of the marathon is to familiarize yourself with the sky by manually finding all of the objects. About 2/3rds of the list is reasonably easy in a 6″-8″ scope in reasonably dark skies. There are a number of dim and difficult objects that require dark skies to see. You have enough time for a quick look before you must start looking for the next object.

Types of Marathons

  • Traditional Marathon – manual scope (tracking OK), printed maps only, no electronic help, no setting circles, group work OK and encouraged.
  • Pairs Marathon – 2 astronomers share a scope and take turns finding objects. Otherwise, the same as a traditional marathon. Having a partner to look at maps and double-check your process makes it an easier task than a solo marathon.
  • Half Marathon – You do a traditional marathon to a set time and try for the maximum number of objects visible up to that time. You could do the second half in the fall to get them all.
  • Binocular Marathon – 10x50mm binoculars can pick up most of the objects in the catalog and larger binos can complete the list.
  • Go-To Marathon – Computerized scopes take all the challenge out of finding the objects, but if they run while others are manually finding objects, then the traditional marathoners can view the object in question to verify they have the right object. It also gives you a longer view of each object.
  • Photographic Marathon – Trying to get enough photons from each object to register an identifiable image is quite a challenge. A large telescope and very sensitive camera really helps.
  • Messier Marathon from Memory – For the experienced astronomer only! Finding all of the objects from memory with no assistance!
  • Herschel Hustle – If you are bored with the Messier catalog, try the Herschel hustle, which is finding 74 objects in Herschel’s catalog at the meridian, moving in declination only with a 150 power, 15-20 arc-minute field. To see all 74 objects, you’ll need a 14 inch or larger scope.

Recognition

Marathon Advice

  • Pick a dark site with low horizons and little light pollution.
  • Make a plan for the object sequence and rough timing to help keep you on track.
  • A 6″ to 10″ telescope recommended
    • You can see all objects in a 3″ telescope and very dark skies.
    • f/4 to f/7 focal ratio recommended
    • A Telrad finder is a huge help, especially with Telrad finder charts
    • 50 mm binoculars are a big help surveying the sky when hopping between objects. Many of the objects are easily visible in binoculars.
  • Remember to have fun! Don’t stress out and ask others for help!
  • Keep warm:
    • Cold hands, feet, and heads make for a miserable night.
    • Dress in layers so you can add or remove as you need to.
    • Handwarmers, electric vests and gloves, and shelter from the wind are big bonuses.
  • Bring a comfortable folding chair
  • A small table for charts, lists, and logbook
  • Thermos with hot drinks
  • Red flashlight and/or red headlamp.
  • Extra batteries

Why Spring?

A vast majority of the Messier marathons are run in Spring because the objects are not evenly distributed in the heavens. There is a gap between M30 and M74/77 that is just large enough to allow the Sun to set/rise with those objects just above the horizon. This usually occurs on New Moon weekends in March and April.

www.peterboroughastronomy.com

You can do a partial marathon in a smaller gap in the Fall. Here is a star atlas of the whole sky marked with the location of the Messier objects:

Star atlas of the Messier Objects
commons.Wikimedia.org

The most difficult objects will be the objects closest to the sun that will rise or set in twilight:

Messier Marathon Map

Part of planning for a Messier marathon is creating a list of objects based on the time of night and their visibility on the Marathon night. You’ll find many marathon sequence lists on the web that will vary quite a bit in individual areas, but agree in general. Perhaps looking at the all-sky map marked with a sequence will clarify that a bit:

www.peterboroughastronomy.com

Now let’s look at the starting sequence:

The evening marathon path
www.peterboroughastronomy.com

The line between M77-M74 is roughly parallel to the horizon during marathon season, so you need to rush to complete the early objects from M77 to M79. Once you get M79, then you’ll have more time to hop through objects. Going up from M79, it’s easy to see you have options for the path up through M37. However, it makes no sense to find M67 before hitting M103. The same is true for all segments of the map.

Midnight sequence
www.peterboroughastronomy.com

The midnight sequence contains some difficult objects, especially the cluster of galaxies at center. Again, you’ve got quite a few options in sections.

Morning Sequence
www.peterboroughastronomy.com

Messier Marathon Guides

Messier Marathon Sequences

Star Hopping Info

Hopping Messier Maps (PDF)

Messier Marathon Logbooks

Recommended Reading

  • The Observing Guide to the Messier Marathon by Don Machholz (Amazon) THE reference to all things marathon. (Expensive)