Planetary Skylights: The Messier Marathon
This is a challenge you might want to undertake in March: an all-night endurance race to observe, before the Sun rises, as many of the 110 deep sky objects listed in Charles Messier’s catalogue.
For many amateur astronomers the two weeks following the spring equinox are regarded as the crème de la crème of observing windows (providing moonlight is absent, as it is at the end of March this year). The reason why this period is so special is the duration of observing time, coupled with the distribution of objects in the sky. This combination allows constellations associated with all four seasons to be viewed over the course of one night. Because of this, astronomers’ thoughts may turn to undertaking the Messier marathon . . . not a long distance race in some obscure city, but a race against the Sun.
Let me explain further. The celestial dome is home to a variety of exotic ‘deep sky’ objects, many of which are visible in amateur scopes (if you know where to look). The more conspicuous of these have proper names – such as the Orion nebula or the Pleiades etc – but many also have an ‘M’ number designation. For example the great nebula in Orion is also known as M42, and the Pleiades are M45. The letter M stands for Messier, but to discover who Messier was we must travel back over 200 years.
In the middle of the eighteenth century, astronomy stood at the threshold of a great observational age and the discovery and subsequent observation of a comet was considered to be of particular importance, bringing peer recognition, fame and fortune to the discoverer. Astronomers at observatories across Europe swept the heavens, looking for these visitors from the depths of space, hoping to find one and claim the spoils. One of the leading comet hunters of the day was the Frenchman, Charles Messier, based at the Paris Royal Observatory. Throughout years of observations, Messier encountered many diffuse and fuzzy objects that could be mistaken for a comet. With assistance from his colleague Pierre Mechain, Messier published in three volumes the location, co-ordinates and description of these objects so that all observers would know of their whereabouts.
Over the intervening years the Messier catalogue has been revised several times and in its current form 110 objects are listed. Entries include: 40 galaxies, 55 star clusters of two types, 11 various nebulae, a few other objects and the catalyst for his work, a supernova remnant, the Crab Nebula in Taurus or M1.
At least a score of Messier objects may be seen on most nights, but because of their distribution in the sky, early spring is especially suited for observing. Galaxies and open star clusters are found in abundance throughout the winter/spring constellations visible during the first part of the night, whilst globular clusters and many nebulae associated with summer skies are visible before dawn.
This is how the idea of the Messier Marathon arose, observing as many entries in an all-night endurance race before the Sun rises. Attempted by many amateur astronomers in the northern hemisphere, few complete it, or indeed can complete it, and from the UK latitude it is not possible. Nevertheless on a clear, moonless (or at least nothing greater than a four-day-old or 23-day-old moon), a UK observer can still spot upwards of 80 entries.
You don’t even require a large telescope to spot many of the Messier objects: binoculars are sufficient to reveal several dozen, and a very modest aperture will reveal nearly all the rest (admittedly a larger amateur scope will help with some of the galaxies in Virgo!). You may be quite surprised at some of the objects on the list. For instance, M45, the Pleiades star cluster star also known as the Seven Sisters, is easily seen with the naked eye. As mentioned, the Orion nebula is M42. The Andromeda galaxy is M31 and the Beehive star cluster in Cancer is M44. Any decent night sky reference book or star chart will have Messier numbers marked, so pick a few out and try your hand at tracking them down in the sky. It’s quite fun, very rewarding, a little frustrating at times, but ultimately you will learn to find your way around the sky. There is even a dark sky window in early March (until the 10th) so you can have two bites of the Messier cherry this year! Good hunting.
Mark Dawson, Whitby & District Astronomical Society
www.whitby-astronomers.com
For many amateur astronomers the two weeks following the spring equinox are regarded as the crème de la crème of observing windows (providing moonlight is absent, as it is at the end of March this year). The reason why this period is so special is the duration of observing time, coupled with the distribution of objects in the sky. This combination allows constellations associated with all four seasons to be viewed over the course of one night. Because of this, astronomers’ thoughts may turn to undertaking the Messier marathon . . . not a long distance race in some obscure city, but a race against the Sun.
Let me explain further. The celestial dome is home to a variety of exotic ‘deep sky’ objects, many of which are visible in amateur scopes (if you know where to look). The more conspicuous of these have proper names – such as the Orion nebula or the Pleiades etc – but many also have an ‘M’ number designation. For example the great nebula in Orion is also known as M42, and the Pleiades are M45. The letter M stands for Messier, but to discover who Messier was we must travel back over 200 years.
In the middle of the eighteenth century, astronomy stood at the threshold of a great observational age and the discovery and subsequent observation of a comet was considered to be of particular importance, bringing peer recognition, fame and fortune to the discoverer. Astronomers at observatories across Europe swept the heavens, looking for these visitors from the depths of space, hoping to find one and claim the spoils. One of the leading comet hunters of the day was the Frenchman, Charles Messier, based at the Paris Royal Observatory. Throughout years of observations, Messier encountered many diffuse and fuzzy objects that could be mistaken for a comet. With assistance from his colleague Pierre Mechain, Messier published in three volumes the location, co-ordinates and description of these objects so that all observers would know of their whereabouts.
Over the intervening years the Messier catalogue has been revised several times and in its current form 110 objects are listed. Entries include: 40 galaxies, 55 star clusters of two types, 11 various nebulae, a few other objects and the catalyst for his work, a supernova remnant, the Crab Nebula in Taurus or M1.
At least a score of Messier objects may be seen on most nights, but because of their distribution in the sky, early spring is especially suited for observing. Galaxies and open star clusters are found in abundance throughout the winter/spring constellations visible during the first part of the night, whilst globular clusters and many nebulae associated with summer skies are visible before dawn.
This is how the idea of the Messier Marathon arose, observing as many entries in an all-night endurance race before the Sun rises. Attempted by many amateur astronomers in the northern hemisphere, few complete it, or indeed can complete it, and from the UK latitude it is not possible. Nevertheless on a clear, moonless (or at least nothing greater than a four-day-old or 23-day-old moon), a UK observer can still spot upwards of 80 entries.
You don’t even require a large telescope to spot many of the Messier objects: binoculars are sufficient to reveal several dozen, and a very modest aperture will reveal nearly all the rest (admittedly a larger amateur scope will help with some of the galaxies in Virgo!). You may be quite surprised at some of the objects on the list. For instance, M45, the Pleiades star cluster star also known as the Seven Sisters, is easily seen with the naked eye. As mentioned, the Orion nebula is M42. The Andromeda galaxy is M31 and the Beehive star cluster in Cancer is M44. Any decent night sky reference book or star chart will have Messier numbers marked, so pick a few out and try your hand at tracking them down in the sky. It’s quite fun, very rewarding, a little frustrating at times, but ultimately you will learn to find your way around the sky. There is even a dark sky window in early March (until the 10th) so you can have two bites of the Messier cherry this year! Good hunting.
Mark Dawson, Whitby & District Astronomical Society
www.whitby-astronomers.com
