Greetings, stargazers.
This is a milestone column for me, as it is the 10th anniversary of my first What’s Up in Durango Skies. I always try to come up with some new astronomical topic to discuss, but there is also the comfort of seasonal familiarity with what you can see in the sky.
If you have been reading my column for a while, you should also be familiar with my seasonal complaint about daylight saving time. It is time for Colorado to get rid of it and join Arizona and Hawaii by sticking with standard time all year long.
I am happy for the recent snow, but spring is almost here, and spring is galaxy season, and also the time of year when you can attempt a Messier Marathon.
Charles Messier (1730-1817) was a French comet hunter. While he did discover 13 comets, his more famous contribution to astronomy was a list he made of objects that were not comets.
In the small telescope he had available, the only way to distinguish a comet from any other dim, fuzzy object was whether or not it moved in the sky from one night to the next. To avoid unnecessary observations, Messier recorded the locations of the stationary objects he found. Anything that was dim and fuzzy and did not move from night to night would make it onto his list.
The final list of 110 objects includes galaxies, diffuse nebulae, planetary nebulae, globular clusters and open clusters. The only thing they have in common is that they are, in fact, not comets. Many are faint, naked-eye objects, and many more can be seen with binoculars. All can be seen with a small telescope, although some might be a challenge.
The Messier objects are not distributed evenly around the sky. Because Messier was observing from the Northern Hemisphere the objects on the list are visible in the Northern Hemisphere. A bit by chance, the part of the sky the sun is in in late March doesn’t have any Messier objects. What this means is that it is possible to observe all 110 objects on a single night, because none will be obscured by the sun. Finding all 110 in a single night is called a Messier Marathon. I wish you the best of luck if you are going to attempt that.
The full moon is on March 20, the same day as the equinox. Because the moon is bright and many of the Messier objects are dim, the days around the 20th are not the time to make the marathon attempt.
If you don’t want to track down all 110, here are some easy Messier objects to find. As always, a star chart app will help with identification.
M42 is the Orion nebula I discussed last month. It is visible to the naked eye, but binoculars will reveal a nice fuzzy patch, and a small telescope will reveal one of the most rewarding deep space objects in the list.
Object No. 45 on Messier’s list is the Pleiades, or Seven Sisters. This is an open cluster easy to see with the naked eye.
The most distant object visible to the unaided eye is M31 – the Andromeda galaxy. It should be visible in the western sky as soon as it is dark enough. If you are attempting a Messier Marathon, there are two less prominent companions that are likely in the same field of view of a small telescope. M32 is a very small companion galaxy to M31. At low magnification, M32 might be mistaken for a nearby star if you don’t notice the slight fuzziness.
Also in the field of view with M31 is M110, another companion that has a very low surface brightness. It is easier to notice such objects through the eyepiece if you use “averted vision.” In other words, don’t look directly at the place you think it is, but look slightly off to the side. By moving your gaze around in the eyepiece, you can catch a glimpse of much fainter things than by looking directly at them.
Charles Hakes teaches in the physics and engineering department at Fort Lewis College and is the director of the Fort Lewis Observatory. He can be reached at hakes_c@fortlewis.edu.
LIST OF MESSIER OBJECTS: http://en.wikipedia.org/wiki/List_of_Messier_objects.
SUGGESTIONS FOR A MESSIER MARATHON: http://www.richardbell.net/marathon.html.
ASTRONOMY PICTURE OF THE DAY: http://apod.nasa.gov/apod.
OLD FORT LEWIS OBSERVATORY: www.fortlewis.edu/observatory.
AN ASTRONOMER’S FORECAST FOR DURANGO: https://bit.ly/2eXWa64.
FOUR CORNERS STARGAZERS: https://bit.ly/2pKeKKa.
