Shapley-Ames Catalog

The Shapley-Ames Catalog of Bright Galaxies is a catalog of galaxies published in 1932 that includes observations of 1249 objects brighter than 13.2 magnitude.[1] It was compiled by Harlow Shapley and Adelaide Ames. They identified 1189 objects based on the New General Catalogue and 48 based on the Index Catalogue.[2] With the help of new photographic recordings, which also contained comparison stars of known brightness, the brightness of many galaxies were measured and recorded only up to a magnitude of 13.2. It was the first compilation of bright galaxies in the northern and southern sky. The catalog contains position, brightness, size, and Hubble classification of the galaxies. For the next 60 years, astronomers referred to this catalog as a primary source for information about redshifts and galaxy types.[3]

History

Shapley and Ames began their study of all nearby galaxies in 1926.[3] An important finding from this research was that the galaxies were not evenly distributed (they violated the isotropy assumption) in that the northern hemisphere contained more galaxies than the southern hemisphere.[4] It also found that the Virgo cloud extended further than previously believed.[5] From this data, Shapley and Ames therefore created a new hierarchy of clusters called a supercluster, which is a cluster of galaxy clusters, and called this Virgo cloud in the northern hemisphere a "Local Supercluster".[6]

Revised Shapley-Ames Catalog

In 1981, Allan Sandage and Gustav Tammann published an updated version known as the Revised Shapley-Ames Catalog (RSA).[4] The original list of galaxies was maintained, with the exception of three objects which were no longer considered galaxies. The information on the 1246 individual galaxies have been updated and substantially extended.

gollark: From the official docs.
gollark: "Features:- Fortunes/Dwarf Fortress output/Chuck Norris jokes on boot (wait, IS this a feature?)- (other) viruses (how do you get them in the first place? running random files like this?) cannot do anything particularly awful to your computer - uninterceptable (except by crashing the keyboard shortcut daemon, I guess) keyboard shortcuts allow easy wiping of the non-potatOS data so you can get back to whatever nonsense you do fast- Skynet (rednet-ish stuff over websocket to my server) and Lolcrypt (encoding data as lols and punctuation) built in for easy access!- Convenient OS-y APIs - add keyboard shortcuts, spawn background processes & do "multithreading"-ish stuff.- Great features for other idio- OS designers, like passwords and fake loading (est potatOS.stupidity.loading [time], est potatOS.stupidity.password [password]).- Digits of Tau available via a convenient command ("tau")- Potatoplex and Loading built in ("potatoplex"/"loading") (potatoplex has many undocumented options)!- Stack traces (yes, I did steal them from MBS)- Backdoors- er, remote debugging access (it's secured, via ECC signing on disks and websocket-only access requiring a key for the other one)- All this useless random junk can autoupdate (this is probably a backdoor)!- EZCopy allows you to easily install potatOS on another device, just by sticking it in the disk drive of any potatOS device!- fs.load and fs.dump - probably helpful somehow.- Blocks bad programs (like the "Webicity" browser).- Fully-featured process manager.- Can run in "hidden mode" where it's at least not obvious at a glance that potatOS is installed.- Convenient, simple uninstall with the "uninstall" command.- Turns on any networked potatOS computers!- Edits connected signs to use as ad displays.- A recycle bin.- An exorcise command, which is like delete but better.- Support for a wide variety of Lorem Ipsum."
gollark: You would need to get rid of the autoupdate capabilities of potatOS itself, or swap them to your own pastebins/github stuff, and then keep everything in line with the current versions.
gollark: Anyway, <@151391317740486657>, what you can do is fork potatOS and get rid of the bits you don't like, but that's also hard (less, though) and would be very difficult to keep updated.
gollark: That doesn't count.

References
  1. Albrecht Unsöld; Bodo Baschek (1 January 2001). The New Cosmos: An Introduction to Astronomy and Astrophysics. Springer. p. 402. ISBN 978-3-540-67877-9.
  2. Steinicke. Observing and Cataloguing Nebulae and Star Clusters. Cambridge University Press. p. 467. ISBN 978-1-139-49010-8.
  3. Allan Sandage (2004). Centennial History of the Carnegie Institution of Washington: Volume 1, The Mount Wilson Observatory: Breaking the Code of Cosmic Evolution. Cambridge University Press. pp. 491–2. ISBN 978-0-521-83078-2.
  4. Vera C. Rubin (1997). Bright Galaxies, Dark Matters. Springer. p. 89. ISBN 978-1-56396-231-8.
  5. Ronald Newbold Bracewell (1 January 1959). Paris Symposium on Radio Astronomy, Held from 30 July to 6 August 1958. Stanford University Press. pp. 351–. ISBN 978-0-8047-0571-4.
  6. Wolfgang Steinicke (2007). Galaxies and How to Observe Them. Springer. pp. 45. ISBN 978-1-85233-752-0.


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