DESCRIPTION AND
DATA SHEET

Montes Apenninus
(Imbrium Basin Rim)
Montes Apenninus, Moon

This Apollo stereo view shows the area adjacent to the rim of the Imbrium impact basin. At least 17 major impact basins (larger than 500 kilometers across) have been identified on the Moon. The Imbrium Basin is roughly 1100 kilometers across and is the second largest impact feature on the Moon. Imbrium formed when an asteroid (or comet) roughly 100 kilometers across slammed into the Moon 3.85 billion years ago. The steep scarp in the upper left is the Montes Apenninus, a 4- to 5-kilometer-high mountain range (adjacent to the Apollo 15 Landing Site) that forms the main rim of the Imbrium Basin. Southeast of the rim is a highly textured terrain known as Apenninus material. This is the inner part of the ejecta deposit formed by the Imbium event, a deposit that extends at least 1000 kilometers from the crater rim. Lava flows have partially flooded low-lying areas within the ejecta blanket.

Near the rim of Imbrium, the terrain is dominated by ridges and troughs that are concentric to the basin rim. The concentric ridge pattern may be related to minor faults concentric to the rim. Further out, at distances of 50 to 100 kilometers from the rim (at Lacus Felicitatis), the topography decreases, as does the thickness of the ejecta deposit. The texture of the surface also changes and ridge orientations can be radial or concentric to the Imbrium rim. More than a few hundred kilometers from Imbrium (at Davy), the texture within the ejecta blanket has features that are mostly radial to Imbrium.

The huge linear feature prominent in the center of this view is neither radial nor concentric to the Imbrium Basin rim. Its origin is unknown.

DATA SHEET (Top)

Location:
     19.8 N, 1.3 E
Quadrangle:
     LTO 41C4, LTO 41C1
Mission:
     Apollo 17
Image Numbers:
     AS17-M-1823, AS17-M-1825
Image Resolution
(Full-Sized View):
     137 meters/pixel
Image Width:
     74 kilometers
Vertical Exaggeration:
    3.1 × Normal
Vertical Resolution:
    4.7 meters
Spacecraft Altitude:
    104 kilometers
Stereo Baseline:
    64 kilometers
Convergence Angle:
    34°