Radial velocity (cz) with respect to the Virgo cluster: vvir
The velocity corrected for infall of the Local Group towards Virgo
is noted vvir. It is calculated as:
vvir = vlg + 208 cos(theta)
Where vlg is the velocity relative
to the Local Group, 208 km/s is the infall velocity of the Local Group
according to Theureau et al. 1998
and Terry et al. 2002
and where theta is the angular distance between the observed direction
and the direction of the center of the Virgo cluster (SG 104 -2).
In older versions, LEDA used the value of the infall velocity to Virgo 170 km/s,
from Sandage & Tammann (1990).