Keeler is the large 160 km crater at the upper right of Ridge
Section 129. It is connected along the eastern edge to
Heaviside, a walled plain of similar dimensions. Keeler,
however, is the younger of the two formations, with more
clearly delineated features. To the northeast of Keeler is the
smaller crater Stratton, and to the northwest lies Ventris.
The outer rim of Keeler is roughly circular, with a straight
segment where it is joined to Heaviside. The northern portion
of the rim is more irregular, with an outward protuberance to
the north-northwest. Portions of the inner wall have a terrace
structure, especially along the southern half. Within the
crater interior, Plante lies on the eastern floor, adjacent to
the inner wall. There is an interior ridge that runs from
about the midpoint toward the west-southwest. The floor is
generally level, with some areas of irregularity to the south.
A few small and tiny craterlets mark the interior plain.
Measurements with the electron reflectometer instrument on
board the Lunar Prospector showed that this crater is one of a
number of impact sites that show demagnetization. The low
magnetic reading lies at the center of this crater, and the
reduced field extends outward to about one and a half crater
diameters. Scientists believe that shock demagnitization is
the cause. (Credit: A lot of the information used in the
section feature descriptions was obtained from Wikipedia.org.
Section 129 and this directory was created by Fran Ridge and
Ned Haskin of The Lunascan Project).