Messier Marathon Night, March 29th 2014 at Charterhouse Observatory

This meeting is open to WMA members and members of other astronomical societies.

The evening will kick off from about 5:30pm when participants can set up their equipment outside the Centre. At 7:00pm there will be a short introductory talk and slide show on Charles Messier and his catalogue by Chris Starr, after which we'll have a great night of deep-sky hunting and discovery (weather permitting).



Charles Messier - Image: Wikipedia

Charles Messier (1730-1817) was one of the greatest observational astronomers of his age. Having come toParisin his late teens to work as an astronomer’s assistant, he went to work for wealthy astronomy professor, Joseph Delisle, in 1751. He became a very competent observer and recorder of astronomical events at Paris Marine Observatory, eventually becoming Chief Astronomer of the Navy inFrance.

He was renowned as a comet hunter – King Louis XIV called him ‘le furet des comètes’, the ‘comet ferret’ – discovering his first comet in 1758, and going on to observe over 20 in all. He was particularly gifted in predicting comet orbits, including his first project observing the return of Halley’s Comet.

When hunting for comets he frequently came across ‘fuzzy’ objects in the sky, so, to avoid confusion he began cataloguing these. The first version of his catalogue, published in 1774, included 45 objects, which increased to 104 objects in his final 1784 edition of the catalogue. He worked with his assistant Pierre Méchain, who discovered at least 20 of these objects.

There are 110 deep-sky objects listed in the Messier catalogue today, as another 7 objects were added between 1921-1966 which were recognized as having been observed by either Messier or Méchain. Each object is designated today by the letter M plus its number, e.g. M1 (the Crab Nebula in Taurus), M31 (the Andromeda Galaxy) or  M42 (the Orion Nebula).

Observing Messier’s objects

The Messier Objects, under good viewing conditions, are visible in small telescopes. Many are even visible in binoculars if you know where to find them.

You won’t see them in the full-colour glory of images taken by large telescopes because:

1)  Your eyes don’t see in colour in dim light – faint, extended objects are more likely to appear greyish;

2)   You need to collect light over a long exposure time to see the fine detail.


Many of the objects are be thrilling to see even in a small-to-medium instrument! Remember to try using averted vision to capture fainter detail.

The Messier Marathon

There is a period in the year when it is theoretically possible to view all of the Messier objects in the course of a single night. The Messier Marathon is the attempt to do this. There is a window of a few weeks from mid-March to early April when it is possible, as the Sun lies in a relatively Messier-free part of the sky, so the objects are sufficiently far from it to be seen.

Messier compiled his catalogue from a northern latitude, so not all of the objects are visible from the southern hemisphere. Low northern latitudes are best (say 25-35°N), but we have a reasonable view from our location at 51° N, where the optimum date is during early-mid-March. A moonless night is best to enhance your chances of seeing these deep-sky objects.

If you can’t get a clear or relatively moonless night in March, there is also a short period around the autumn equinox when most of the Messier objects can be seen.

For much useful information on doing the Messier marathon visit:

Of course, you don’t have to try and see them all in one night. Discovering them in your own time is rewarding and exciting.


M45 The Pleiades - Image: Aiglon College

Clear skies and happy hunting!