Virgo I

{{Short description|Extremely faint satellite galaxy of the Milky Way}}

{{Infobox galaxy

| image =

| caption =

| name = Virgo I

| epoch = J2000

| type = dSph

| ra = {{RA|12|00|09.6}}

| dec = {{DEC|-00|40|48}}

| dist_ly = {{val|280|+42|-26}} kly
(87 {{su|p=+13|b=−8}} kpc)

| z =

| appmag_v =

| half_light_radius_pc = {{val|38|+12|-11}} pc

| half_light_radius_arcminsec = 1.5′

| constellation name = Virgo

| absmag_v=−0.8 ± 0.9

| ellipticity = 0.44

| names = Virgo I

}}

Virgo I is an extremely faint satellite galaxy of the Milky Way.{{cite web|title=Record-breaking faint satellite galaxy of the Milky Way discovered|url=http://phys.org/news/2016-11-record-breaking-faint-satellite-galaxy-milky.html|website=PhysOrg|access-date=24 November 2016|date=22 November 2016}} It was discovered in the Subaru Strategic Survey. Virgo I has an absolute visual magnitude of −0.8 making it one of the least luminous galaxies confirmed thus far. The galaxy has a radius of 124 light years, (half light radius 38 pc) meaning that it is too big to be a globular cluster. Cetus II is dimmer, but too small to be classed as a galaxy. Virgo I is dimmer than Segue I, the previous dimmest known. The distance to Virgo I is {{convert|87|kpc|ly}}.{{cite journal|last1=Homma|first1=Daisuke|last2=Chiba|first2=Masashi|last3=Okamoto|first3=Sakurako|last4=Komiyama|first4=Yutaka|last5=Tanaka|first5=Masayuki|last6=Tanaka|first6=Mikito|last7=Ishigaki|first7=Miho N.|last8=Akiyama|first8=Masayuki|last9=Arimoto|first9=Nobuo|last10=Garmilla|first10=José A.|last11=Lupton|first11=Robert H.|last12=Strauss|first12=Michael A.|last13=Furusawa|first13=Hisanori|last14=Miyazaki|first14=Satoshi|last15=Murayama|first15=Hitoshi|last16=Nishizawa|first16=Atsushi J.|last17=Takada|first17=Masahiro|last18=Usuda|first18=Tomonori|last19=Wang|first19=Shiang-Yu|title=A New Milky Way Satellite Discovered In The Subaru/Hyper Suprime-Cam Survey|journal=The Astrophysical Journal|date=14 November 2016|volume=832|issue=1|pages=21|doi=10.3847/0004-637X/832/1/21| arxiv=1609.04346|bibcode = 2016ApJ...832...21H |s2cid=118700037 |doi-access=free }}