VIRGOHI21

VIRGOHI 21
VIRGOHI 21
Observation data (J2000 epoch)
Constellation	Virgo
Right ascension	12h 17m 53.6s
Declination	+14° 45′ 25″
Redshift	1966 km/s
Distance	50 Mly
Apparent magnitude (V)	< 27
Notable features	No stars

VIRGOHI21 is an extended region of neutral hydrogen (HI) in the Virgo cluster discovered in 2005. Analysis of its internal motion indicates that it may contain a large amount of dark matter, as much as a small galaxy. Since VIRGOHI21 apparently contains no stars, this would make it one of the first detected dark galaxies. Skeptics of this interpretation argue that VIRGOHI21 is simply a tidal tail of the nearby galaxy NGC 4254.

^ ^a ^b ^c "NASA/IPAC Extragalactic Database". Results for VIRGOHI 21. Retrieved 2006-11-19.
^ Cite error: The named reference PPARC was invoked but never defined (see the help page).

[ned-1] "NASA/IPAC Extragalactic Database". Results for VIRGOHI 21. Retrieved 2006-11-19.

[PPARC-2] Cite error: The named reference PPARC was invoked but never defined (see the help page).

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