Messier Marathon

Summary

Astronomy competition Plot of the Messier objects relative to the modern constellations, ecliptic, and Milky Way, using equatorial coordinates (right ascension, declination) A Messier marathon is an attempt, usually organized by amateur astronomers, to find as many Messier objects as possible during one night. The Messier catalogue was compiled by French astronomer Charles Messier during the late 18th century and consists of 110 relatively bright deep-sky objects (galaxies, nebulae, and star clusters). When and where a marathon is possible[edit] The number of Messier objects visible in any one night varies depending on a few factors, including the location of the observer, the duration of daylight and nighttime, and the season (the positions of the Messier objects relative to the Sun varies with the season, as does the length of the night). Because Messier compiled his catalog from a northern latitude, not all of the Messier objects are visible from the southern hemisphere. In particular, M81, M82, M52, and M103 make southern-hemisphere Messier marathons difficult, because they are all located at a declination of 60° north or greater. Although a Messier marathon can be attempted from any northern latitude, low northern latitudes are best. In particular, a latitude of around 25° north lends the best possibility to complete a Messier marathon at the right time of year. At low northern latitudes, particularly around latitude 25° north, it is possible to observe all Messier objects in one night during a window of a few weeks from mid-March to early April. In that period the dark nights around the time of the new moon are best for a Messier marathon. Other times of year[edit] Less complete Messier marathons can be undertaken at other times of the year, with the actual quantity of Messier objects seen depending upon season and location. In particular, there is a short period around the autumnal equinox when most of the objects can be seen.[1] The Messier Marathon was inve...