Number of Galaxies

[katmcc]

I am an artist who loves the astronomy pix of the day. Can someone tell me just how many galaxies have been discovered and named or numbered? I imagine galaxies in paint and other media and would love to number/name them but don't want to step on any scientists' toes.
thanksKat

[neufer]

I am an artist who loves the astronomy pix of the day. Can someone tell me just how many galaxies have been discovered and named or numbered? I imagine galaxies in paint and other media and would love to number/name them but don't want to step on any scientists' toes.

You will find a list of notable galaxies here: http://en.wikipedia.org/wiki/List_of_galaxies

<<The first known galaxies were longly known before their nature as "island universes" came to light - this fact was finally proven only in 1923 by Edwin Powell Hubble, when he found Cepheid variable stars in the Andromeda Galaxy M31. Ancient observers have known the Milky Way and - on the Southern Hemisphere - the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) since prehistoric times. There are speculations that also the Andromeda Galaxy M31 may have been observed and recorded as a nebulous patch by anonymous Babylonian observers around 1,300 B.C.. This object was certainly known to medevial Persian astronomers before 905 A.D., and cataloged and described by Persian astronomer Al Sufi in 964 A.D, who also describes the LMC. Both LMC and SMC have become known by the reports of Vespucci and Magellan in the early 16th century.

All other galaxies have been discovered only after the invention of the telescope: The Triangulum Galaxy M33 was first seen by Italian Priest astronomer G.B. Hodierna before 1654. Next, French astronomer Legentil discovered M32, a companion of the Andromeda Galaxy, in 1749, and his compatriot Nicholas Louis de Lacaille found M83 in 1752, the first galaxy beyond the Local Group to be discovered. These six were all external galaxies to be known, before Charles Messier started to survey the sky for comets and "nebulae." His first original discovery of a galaxy, M49, a giant elliptical member of the Virgo Cluster, occurred in 1771. The Messier Catalog in his modern form contains 40 galaxies, all but the two Magellanic Clouds that have been found up to 1782. Starting in 1783, William Herschel found and cataloged over 2,500 star clusters and "nebulae" up to 1802, 2,143 of them actually galaxies. J.L.E. Dreyer's NGC catalog contains 6,029 (about 75.9%), and his IC catalog another 3,971 galaxies (about 73.7%).

Today's modern catalogs contain far larger numbers; millions of galaxies have been cataloged, and it was estimated that the observable part of the universe contains probably hundreds of billions galaxies. For example, at the time of this writing (2009), the Sloan Digital Sky Survey project has scanned more than about 1/4 of the sky, and determined properties of more than one million of galaxies.>>

<<There are probably more than 170 billion galaxies in the observable universe. Most galaxies are 1,000 to 100,000 parsecs in diameter and are usually separated by distances on the order of millions of parsecs. Intergalactic space (the space between galaxies) is filled with a tenuous gas of an average density less than one atom per cubic meter. The majority of galaxies are organized into a hierarchy of associations called clusters, which, in turn, can form larger groups called superclusters. These larger structures are generally arranged into sheets and filaments, which surround immense voids in the universe.>>

[hairnet]

The total number that we 'could' observe is thought to be around 10^11 (1 followed by 11 zeros! or 100 billion in common terms). Plenty of inspiration as they come in a variety of shapes and sizes!