virgocluster

The Virgo Galaxy Cluster

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Common Name:  The Virgo Cluster
Other Names:   M91
RA:    12 25 1
Dec    +12 53
Constellation: Virgo
Distance:    60 million light years
Magnitude: 8.9 (M86)

Notes: 
The Virgo Cluster with its some 2000 member galaxies dominates our intergalactic neighborhood, as it represents the physical center of our Local Supercluster (also called Virgo or Coma-Virgo Supercluster), and influences all the galaxies and galaxy groups by the gravitational attraction of its enormous mass. It has slowed down the escape velocities (due to cosmic expansion, the `Hubble effect') of all the galaxies and galaxy groups around it, thus causing an effective matter flow towards itself (the so-called Virgo-centric flow). Eventually many of these galaxies have fallen, or will fall in the future, into this giant cluster which will increase in size due to this effect. Our Local Group has experienced a speed-up of 100..400 km/sec towards the Virgo cluster. Current data on the mass and velocity of the Virgo cluster indicate that the Local Group is probably not off far enough to escape, so that its recession from Virgo will probably be halted at one time, and then it will fall and merge into, or be eaten by the cluster, see our Virgo Cluster & Local Group page.

Because of the Virgo Cluster's enormous mass, its strong gravity accelerates the member galaxies to considerably high peculiar velocities, up to over 1500 km/sec, with respect to the cluster's center of mass. Investigations over the past decades have revealed a quite complex dynamic structure of this huge irregular aggregate of galaxies. The Virgo cluster is close enough that some of its galaxies, which happen to move fast through the cluster in our direction, exhibit the highest blue-shifts (instead of cosmological redshifts) measured for any galaxies, i.e. are moving toward us: The record stands for IC 3258, which is approaching us at 517 km/sec. As the cluster is receding from us at about 1,100 km/sec, this galaxy must move with over 1,600 km/sec through the Virgo Cluster's central region. Analogously, those galaxies which happen to move fastest away from us through the cluster, are receding at more than double redshift than the cluster's center of mass: The record is hold by NGC 4388 at 2535 km/sec, so that this galaxy moves peculiarly in the direction away from us at over 1,400 km/sec. 
Ref: Quoted from  http://www.seds.org/Messier/more/virgo.html

In the above photo, there are some 10 galaxies, M86 the largest centre left, above and to the left is M84, to the lower left of M86 is NGC4402, to the right of M84 isNGC 4388, etc.
M86 is travelling towards us as it is blue shifted. It is a giant elliptical or lenticulargalaxy. A dwarf companion galaxy can be seen on the image below taken with the canon camera.
Ngc 4402 is an edge on spral galaxy

Telescope: Meade LX200GPS 14"
Camera: SBig ST-8
Filters: CBVR
Exposure:  
Date: 2006
Where: Tenby Observatory, Coonabarabran
Lat: 31 16 35.05 S,  Long  149 11 33.99 E,  Elevation 547metres