Arp 104

Infobox Galaxy
name=Arp 104


caption=
credit=
epoch=J2000
constellation name=Ursa Major
ra=RA|13|32|08.9cite web
url=http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=arp+104&extend=yes&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES
title=Searching NED for object "ARP 104*"
accessdate=2008-08-02
work=NASA/IPAC Extragalactic Database (NED)
publisher=Jet Propulsion Laboratory, California Institute of Technology]
dec=DEC|+62|44|02
z=0.010817
dist_ly=1.73 × 10⁷
type=E0/SBb-peccite web
url=http://arxiv.org/pdf/astro-ph/0605015v1
title=Imaging and spectroscopy of Arp 104: a post-starburst interacting pair with cross-fuelling?
accessdate=2008-08-02
last=Roche
first=Nathan
date=2006-04-29
format=PDF
pages=1 arxiv|astro-ph|0605015v1]
appmag_v=14.0cite web
url=http://seds.org/~spider/ngc/ngc.cgi?5216
title= NGC 5216
accessdate=2008-08-03
work=The interactive NGC catalog online
publisher=Students for the Exploration and Development of Space (SEDS)] /12.3cite web
url=http://seds.org/~spider/ngc/ngc.cgi?5218
title= NGC 5218
accessdate=2008-08-03
work=The interactive NGC catalog online
publisher=Students for the Exploration and Development of Space (SEDS)]
size_v=
notes=bridged
names=Keenan's system

NGC 5216/NGC 5218

UGC 8528/UGC 8529cite web
url=http://arxiv.org/pdf/astro-ph/9911186v1
title=The molecular gas-star formation connection in an optically-selected sample of interacting galaxies
accessdate=2008-08-03
last=Bushouse
first=Howard A.
coauthors=Steven D. Lord, Susan A. Lamb, Michael W. Werner, K. Y. Lo
date=1999-11-10
format=PDF
pages=13 arxiv|astro-ph|9911186]

VV 33acite web
url=http://simbad3.u-strasbg.fr/sim-id.pl?Ident=NGC5216
title=NGC 5216 -- Interacting Galaxies
accessdate=2008-08-03
work=SIMBAD astronomical object database
publisher=Centre de Données astronomiques de Strasbourg] /VV 33bcite web
url=http://simbad3.u-strasbg.fr/sim-id.pl?Ident=NGC5218
title=NGC 5216 -- Interacting Galaxies
accessdate=2008-08-03
work=SIMBAD astronomical object database
publisher=Centre de Données astronomiques de Strasbourg]

Arp 104, also known as Keenan's system, is entry 104 in Halton Arp's Atlas of Peculiar Galaxies catalog for spiral galaxy NGC 5216 and globular galaxy NGC 5218.cite web
url=http://www.universetoday.com/2008/07/25/bridge-across-space-keenans-system-by-martin-winder-and-dietmar-hager/
title=Bridge Across Space: "Keenan's System" by Martin Winder and Dietmar Hager
accessdate=2008-08-02
last=Plotner
first=Tammy
date=2008-07-25
publisher=Universe Today] The two galaxies are joined by a bridge of galactic material spanning 22 000 light years.cite journal
last=Zwicky
first=Fritz
authorlink=Fritz Zwicky
year=1956
title=Multiple galaxies
journal=Ergebnisse der exakten Naturwissenschaften
volume=29
pages=361
bibcode=1956ErNW...29..344Z
url=http://articles.adsabs.harvard.edu//full/1956ErNW...29..344Z/0000361.000.html
accessdate=2008-08-02]

In 1790 William Herschel discovered the galaxies, and in 1926 they were studied Edwin Hubble. In 1935 Philip C. Keenan first published a paper about the bridge connecting the galaxiescite journal
last=Keenan
first=Philip C.
year=1935
month=05
title=An unusual pair of nebulae: NGC 5216 and 5218
journal=Astrophysical Journal
volume=81
pages=355
doi=10.1086/143641
bibcode=1935ApJ....81..355K
url=http://adsabs.harvard.edu/abs/1935ApJ....81..355K
accessdate=2008-08-02] , which was rediscovered in 1958 at the Lick and Palomar observatoriescite journal
last=Vorontsov-Vel'Iaminov
first=B. A.
authorlink=Boris Vorontsov-Velyaminov
date=1958
title=The interaction of galaxies and the nature of their arms, spanning filaments and tails. The morphology of galaxies. V.
journal=Astronomicheskii Zhurnal
volume=35
pages=858
bibcode=1958AZh....35..858V
accessdate=2008-08-02] .

References

External links

*cite web
url=http://antwrp.gsfc.nasa.gov/apod/ap080731.html
title=Galaxies on a string
accessdate=2008-08-02
last=Nemiroff
first=Robert
coauthors=Jerry Bonnell
date=2008-07-31
work=Astronomy Picture of the Day
*Winder, Martin; Dietmar Hager. " [http://www.stargazer-observatory.com/5216-martin.html NGC 5216 + 18] ". "Stargazer Observatory". Retrieved on 2008-08-02.