Charles Messier was a French astronomer who compiled and published a list of nebulae, star clusters, and galaxies, which came to be known as the Messier objects. Messier was mainly hunting for comets but sometimes ran across objects that looked like comets but were subsequently disproven. Messier’s original list identified 103 such objects that comet hunters should “ignore” – seven additional entries have been added over the years, bringing the total to 110.
A Messier Marathon is an attempt to observe all 110 objects in a single night. The best time of year to attempt a Messier Marathon is often around a new Moon in March. This weekend, March 9th&10th, is just a few days past the new Moon and the forecast for the Lower Mainland is for mostly clear skies so it provides a nice opportunity.
But some objects in Messier’s list will not be visible from latitudes above 40° north this weekend. Alan Whitman, a BC resident, has a “cover page” article in the April edition of Sky and Telescope magazine that suggests April 4th-5th, 2019 is the perfect night for a Messier Marathon from latitudes above 49° north. Even then, observing all 110 objects may not be possible.
Planning is required for a serious attempt and the Calgary RASC Centre has some good planning tips and a great planning tool. Howard Trottier recommends a book by Don Machholz as a guide to Messier Marathons.