MAGELLAN PROJECT OFFICE


P-38143
4/19/91
                                


     This crater, partly flooded by volcanic lavas, was mapped by
Magellan on September 20, 1990 during orbits 411 through 418.  It
is located in the Lavinia region of Venus at 59.5 degrees south
latitude and 354.5 east longitude.  It is one of the very few
impact craters that has been documented by Magellan to be actually
in the process of elimination by volcanic resurfacing, and with a
diameter of 63 kilometers (39 miles), it is the largest of these
craters.  The large, trough-like depression on the southwest (lower
left) side is a rille or channel through which lava once flowed. 
A remnant of rough radial ejecta is preserved outside the crater's
southeast rim.  The presence of partly lava-flooded craters, such
as this, are important to our understanding of the rate of
resurfacing on Venus by volcanism.  Resolution of the Magellan data
is about 120 meters (400 feet).

     Alcott, the name proposed for this crater, honors Louisa May
Alcott, American author (1832-1888).  Proposed names for all
features on planetary bodies are provisional until formally adopted
by the International Astronomical Union.


Jet Propulsion Laboratory
California Institute of Technology
National Aeronautics and Space Administration
Pasadena, Calif. 91109