View source for Arp 7

{{Short description| Spiral Galaxy in the constellation of Hydra }}
{{Infobox Galaxy
| name = ARP 7
| image = Arp 7 PanSTARRS1 i.r.g.jpg
|caption = Arp 7 by [[PanSTARRS]]
| credit= Halton Arp
| epoch = [[J2000]]
| type = SB(rs)bc <ref name="ned">{{cite web
  | title=NASA/IPAC Extragalactic Database
  | work=Results for ARP 007
  | url=http://www.ned.ipac.caltech.edu/
  | access-date=2015-11-25
  | archive-url=https://web.archive.org/web/19971222113324/http://ned.ipac.caltech.edu/
  | archive-date=1997-12-22
  | url-status=dead
  }}</ref>
| ra = {{RA|8|50|30.0}}<ref name="simbad">{{cite book
  | publisher=SIMBAD Astronomical Database
  | title=Results for ARP 007
  | url=http://simbad.u-strasbg.fr/simbad/
  | access-date=2015-11-25}}</ref>
| dec = {{DEC|-16|37|00}}<ref name="simbad" />
| dist_ly = {{convert|5.9-83.7|Mpc|Mly|abbr=on|lk=on|order=flip}}<ref name="ned"/>
| z = 0.018356 ± 0.000027 
(5503 ± 8 km/s)<ref name="ned" />
| appmag_v = 12.40<ref name="ned" />
| size_v =  57.1″ &times; 52.53″ <ref name="ned" />
| size = {{convert|1.6|kpc|ly|abbr=on|lk=on|order=flip}} ({{convert|23|kpc|ly|abbr=on|lk=on|order=flip}}?) (estimated){{efn|name=size}}<ref name ="ned" />
| constellation name = [[Hydra (constellation)|Hydra]]<ref name="cseligman">{{cite web
  | first=Courtney
  | last=Seligman
  | title=Celestial Atlas: PCG Objects 24500–4999
  | url=http://cseligman.com/text/atlas/pgc24a.htm
  | access-date=2015-11-25}}</ref>
| notes = 
| names = [[Principal Galaxies Catalogue|PGC]] 024836,<ref name="ned" /> [[Atlas of Peculiar Galaxies|APG]] 7<ref name="simbad" />
}}
{{Sky|08|50|30|-|16|37|00|130000000}}
'''Arp 7''' ('''PGC 24836''') is a [[spiral galaxy]] in the constellation [[Hydra (constellation)|Hydra]].<ref name="cseligman" /> Redshift-independent measurements of its distance vary widely, from 5.9 Mpc to 83.7 Mpc.<ref name="ned" />  Its [[Galaxy morphological classification|morphological classification]] is SB(rs)bc,<ref name="ned" /> meaning it is a [[barred spiral galaxy]] with some ring-like structure.

Arp 7 was imaged by [[Halton Arp]] and included in his [[Atlas of Peculiar Galaxies]] under the category of 'split arm' galaxies.<ref>{{cite web
  | first=Halton
  | last=Arp
  | title=Atlas of Peculiar Galaxies
  | date=1966
  | work=Figure 1
  | url=https://ned.ipac.caltech.edu/level5/Arp/Arp_figure1.html
  | access-date=2015-11-25}}</ref>  Five other galaxies are also included in this section of the atlas: Arp 8 ([[NGC 497]]), Arp 9 ([[NGC 2523]]), Arp 10 ([[UGC 1775]]), Arp 11 (UGC 717), and Arp 12 ([[NGC 2608]]).

==See also==
*[[List of largest galaxies]]

== References ==
{{Reflist}}

==Notes==
{{Notelist|refs=

{{efn|name=size|Calculated from apparent size and distance:<math>5.9-83.7 Mpc*sin(57.1 arcsec) = 5,300 - 75,000 ly</math>}}

}}

== External links ==
* [https://ned.ipac.caltech.edu/level5/Arp/Arp_contents.html Full Arp Atlas]
* [https://web.archive.org/web/20160304073601/https://ned.ipac.caltech.edu/level5/Arp/Arp2.html Arp Atlas image of Arp 7]
* [http://djm.cc/constellation.html Constellation Locator]
* [http://simbad.u-strasbg.fr/simbad/ SIMBAD Astronomical Database]
* [http://ned.ipac.caltech.edu/ NASA/IPAC Extragalactic Database]

{{Astronomical catalogs
| PGC = 24836
| Arp = 7
}}
{{Hydra (constellation)}}

[[Category:Barred spiral galaxies]]
[[Category:Arp objects|007]]
[[Category:Principal Galaxies Catalogue objects|24836]]
[[Category:Peculiar galaxies]]
[[Category:Hydra (constellation)]]


{{Spiral-galaxy-stub}}