Messier Objects & NGC

14.1 - Be able to use the Messier and New General Catalogue (NGC) in cataloguing nebulae, clusters and galaxies
Messier Objects

The French astronomer Charles Messier was a comet hunter. He was fed up of discovering objects that initially looked like comets but weren't, so he published a catalogue which eventually contained 110 of these objects.

These objects are of immense importance to astronomers as they are nebula and galaxies. The objects are prefixed as 'M' so the Crab Nebula in Taurus is M1. He was restricted by the objects he could see from France, making list limited by today’s standards. It remains popular due to the length of time it has been around, as well as astronomers familiarity with the most common of these objects in it.

New General Catalogue

The New General Catalogue of Nebulae and Clusters of Stars (abbreviated as NGC) is a list of galaxies, star clusters, emission nebulae and absorption nebulae catalogued by number.

Objects are prefixed with 'NGC' so the Crab Nebula is 'NGC 1952'.

It was published in 1888 by the Danish-Irish astronomer John Louis Emil Dreyer based on work by the Hershel trio of William, Caroline and John. The first volume had over 1,000 objects in it. Numerous updates and corrections have been published since. Today the 'Revised New General Catalogue and Index Catalogue' (NGC/IC) contains nearly 8,000 objects.

 

Summary

Charles Messier published a catalogue containing 110 of objects such as nebulae and galaxies.
John Louis Emil Dreyer published teh New General Catalogue with over 1,000 objects in it.

Questions
  • What kind of objects are in the Messier catalogue?
  • How would you find a Messier object on a star chart
Did you know?

In springtime some astronomers attempt Messier Marathons, during which they try to locate as many of these objects in one night as possible.

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