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Description
We investigate the distribution and velocity field of galaxies situated in a band of 100x20 degrees centered on M87 and oriented along the Local supercluster plane. Our sample amounts 2158 galaxies with radial velocities less than 2000 km/s. Of them, 1119 galaxies (52%) have distance and peculiar velocity estimates. About 3/4 of early-type galaxies are concentrated within the Virgo cluster core, most of the late-type galaxies in the band locate outside the virial radius. Distribution of gas-rich dwarfs with M_HI_> M* looks to be insensitive to the Virgo cluster presence. Among 50 galaxy groups in the equatorial supercluster band 6 groups have peculiar velocities about 500-1000km/s comparable with virial motions in rich clusters. The most cryptic case is a flock of nearly 30 galaxies around NGC4278 (Coma I cloud), moving to us with the mean peculiar velocity of -840km/s. This cloud (or filament?) resides at a distance of 16.1Mpc from us and approximately 5Mpc away from the Virgo center. Galaxies around Virgo cluster exhibit Virgocentric infall with an amplitude of about 500 km/s. Assuming the spherically symmetric radial infall, we estimate the radius of the zero-velocity surface to be R0=(7.0+/-0.3)Mpc that yields the total mass of Virgo cluster to be (7.4+/-0.9)x10^14^ solar masses, in tight agreement with its virial mass estimates. We conclude that the Virgo outskirts does not contain significant amounts of dark mater beyond its virial core.
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