{{Short description|Ultracompact dwarf galaxy that is the densest galaxy known}} {{Infobox galaxy | name = M85-HCC1 | epoch = [[Epoch (astronomy)#Julian years and J2000|J2000]] | constellation name = [[Coma Berenices]] | image = M59-UCD3 M85-HCCI.png | image_size = 250px | caption = Images of two ultracompact dwarf galaxies. M59-UCD3 is in the inset to the left, while M85-HCC1 is in the inset to the right. | ra = {{RA|12|25|22.842}}<ref name=SIMBAD>{{cite simbad|title=2MASS J12252287+1810539|accessdate=6 May 2018}}</ref> | dec = {{DEC|+18|10|53.67}}<ref name=SIMBAD/> | half_light_radius_pc = 1.85 ± 0.9 [[parsec|pc]]<ref name=Sandoval/> | appmag_v = 18.80 ± 0.03<ref name=Sandoval/> | absmag_v = −12.55 ± 0.07<ref name=Sandoval/> | h_radial_v = 658 ± 4<ref name=Sandoval/> | mass = ({{val|1.2|0.1}}){{X10^|7}}<ref name=Sandoval/> | names = 2MASS J12252287+1810539, SDSS J122522.84+181053.6<ref name=SIMBAD/> }} '''M85-HCC1''' is an ultracompact [[dwarf galaxy]] with a star density 1,000,000 times that of the solar neighbourhood,<ref>{{cite web|title=Hiding in plain sight: Undergraduates discover the densest galaxies known|url=http://phys.org/news/2015-07-plain-sight-undergraduates-densest-galaxies.html|website=physOrg|access-date=29 July 2015|date=27 July 2015}}</ref><ref name=Sandoval>{{cite journal|author=Michael A. Sandoval |author2=Richard P. Vo |author3=Aaron J. Romanowsky |title=Hiding in plain sight: record-breaking compact stellar systems in the Sloan Digital Sky Survey|journal=Astrophysical Journal Letters|date=2015|volume=808|issue=1 |pages=L32|arxiv=1506.08828|doi=10.1088/2041-8205/808/1/l32|bibcode = 2015ApJ...808L..32S |s2cid=55254708 }}</ref> lying near the galaxy [[Messier 85]]. {{as of|2015}}, it is the densest galaxy known.<ref name=SpaceDaily-2015-07-29> {{cite news |url= http://www.spacedaily.com/reports/Undergraduates_discover_the_densest_galaxies_known_999.html |title= Undergraduates discover the densest galaxies known |date= 29 July 2015 |publisher= Space Daily }} </ref> == See also == * [[List of galaxies#Galaxies by mass and density|List of most massive galaxies]] ==References== {{Reflist}}
==See also== * [[M59-UCD3]] (second-densest galaxy known, as of 2015) * [[M60-UCD1]] (another dense galaxy)
{{galaxy-stub}} {{galaxy}}
[[Category:Dwarf galaxies]] [[Category:Astronomical objects discovered in 2015|20150727]] [[Category:Coma Berenices]]