View source for 3C 48

{{Quasar
  | name = [[Third Cambridge Catalogue of Radio Sources|3C]] 48
  | image = Radio map of quasar 3C48.jpg
  | epoch = [[J2000]]
  | ra = {{RA|01|37|41.1}}<ref name="ned">{{cite web
  | title=NASA/IPAC Extragalactic Database
  | work=Results for 3C 48
  | url=http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=3C+48&extend=no
  | accessdate=2006-10-26 }}</ref>
  | dec = {{DEC|+33|09|32}}<ref name="ned" />
  | constellation name = [[Triangulum]]
  | z = 110,024 ± 0 km/[[second|s]]<ref name="ned" /><br/>0.367<ref name="ned" />
  | type = E<ref name=SIMBAD>[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=3C+48 Simbad]</ref>
  | dist_ly = 3.9 [[Giga-|billion]] [[light-year]]s<br/>([[Light travel time]])<ref name=ned/><br/>4.5 billion light-years<br/>([[Comoving distance|present]])<ref name=ned/>
  | appmag_v = 16.2
  | size_v = 0.6´X0.5´
  | notes = First quasar discovered
  | names = [[PG (star catalog)|PG]] 0134+329, [[Quasar|QSO]] B0134+329
}}

'''3C48''' is a [[quasar]] discovered in 1960; it was the second source conclusively identified as such.<ref>{{cite journal | last = Weaver | first = Kenneth F. |authorlink=Kenneth Weaver|date=May 1974 | title = The Incredible Universe | journal=[[National Geographic (magazine)|National Geographic]] | number =   5 | volume = 145 | pages = 589–633}}</ref>

3C48 was the first source in the [[Third Cambridge Catalogue of Radio Sources]] for which an optical identification was found by [[Allan Sandage]] and [[Thomas A. Matthews]] in 1960 through [[interferometry]].<ref>{{cite journal
 | author= Matthews, Thomas A.
 | author-link= Thomas A. Matthews
 | author2= Sandage, Allan R.
 | author2-link= Allan Sandage
 | title=Optical Identification of 3c 48, 3c 196, and 3c 286 with Stellar Objects
 | date=1963
 | journal=[[The Astrophysical Journal]]
 | volume=138
 | pages=30–56
 | bibcode=1963ApJ...138...30M
 | doi=10.1086/147615
 }}</ref>
[[Jesse L. Greenstein]] and Thomas Matthews found that it had a redshift of 0.367, making it one of the highest redshift sources then known.<ref>{{cite journal
 | author=Greenstein, J. L.
 | author-link=Jesse L. Greenstein
 |author2=Matthews, Thomas A.
 |author2-link=Thomas A. Matthews
 | title=Red-Shift of the Unusual Radio Source 3C48
 | date=1963
 | journal=[[Nature (journal)|Nature]]
 | volume=197
 | issue=4872
 | pages=1041–1042
 | bibcode=1963Natur.197.1041G
 | doi=10.1038/1971041a0
 }}</ref>
It was not until 1982 that the surrounding faint galactic "nebulosity" was confirmed to have the same redshift as 3C48, cementing its identification as an object in a distant galaxy.<ref>{{cite journal
 | author=Todd A. Boroson
 | author2=Oke, J. B.
 | last-author-amp=yes
 | title=Detection of the underlying galaxy in the QSO 3C48
 | journal=[[Nature (journal)|Nature]]
 | volume=296
 | issue=5856
 | pages=397–399
 | bibcode=1982Natur.296..397B
 | doi=10.1038/296397a0
 | date=1982}}</ref>  This was also the first solid identification of a quasar with a surrounding galaxy at the same redshift.

3C 48 is one of four primary calibrators used by the [[Very Large Array]] (along with [[3C 138]] and [[3C 147]], and [[3C 286]]). Visibilities of all other sources are calibrated using observed visibilities of one of these four calibrators.<ref name="NRAO">{{cite web |last=Witz |first=Stephan W. |title=Calibration and Flux Density Scale |publisher=[[National Radio Astronomy Observatory]] |date=4 December 2015 |url=https://science.nrao.edu/facilities/vla/docs/manuals/oss/performance/fdscale |accessdate=15 May 2016}}</ref>

== References ==

{{reflist}}

[[Category:Quasars]]
[[Category:3C objects|048]]
[[Category:Astronomical objects discovered in 1960]]