DESCRIPTION AND
DATA SHEET

Montes Haemus
Mare Serenitatis, Moon

This Apollo stereo view of the Serenitatis Basin illustrates the geologic diversity of the Moon. This region, known as Sulpicius Gallus, contains a variety of impact, volcanic, and tectonic features. Most noticeable is the boundary between the rugged highlands (the Montes Haemus) and the smooth basalt seen in Mare Serenitatis.

The Montes Haemus (more commonly referred to as the Haemus Mountains) are part of the prominent 740-kilometer-wide outer ring of the Serenitatis Basin. This basin formed 3.87 billion years ago when an asteroid 50 to 100 kilometers across slammed into the Moon. The Haemus Mountains are 2 to 3 kilometers high, but were probably 5 kilometers high before the basin was flooded by lava flows.

The Serenitatis Basin and most of its central structures were flooded by vast outpourings of basaltic lava after the basin formed (approximately 3.7 to 3.8 billion years ago). Several small volcanic pits can be seen along the edge of the mountains. These may have been source vents for some of the lava flows.

The great weight of the lava deposits caused the center of the basin to sag downward. This placed tensional stress on the outer part of the basin floor, forming a series of concentric fractures and graben called the Fossae Sulpicius Gallus. In contrast, concentric wrinkle ridges formed in response to compressional stresses closer to the center of the basin. They may have formed over buried basin ring structures.

Small impact craters have formed over the past 3 to 4 billion years. The largest of these, Sulpicius Gallus, is a simple bowl-shaped crater 12 kilometers across and 2.2 kilometers deep.

DATA SHEET (Top)

Location:
     20.0 N, 11.0 E
Quadrangle:
     LTO 42D1, LTO 42D4
Mission:
     Apollo 17
Image Numbers:
     AS17-M-1816,
     AS17-M-1818
Image Resolution
(Full-Sized View):
     152 meters/pixel
Image Width:
     86 kilometers
Vertical Exaggeration:
     3.9 × Normal
Vertical Resolution:
     42 meters
Spacecraft Altitude:
     106 kilometers
Stereo Baseline:
     82 kilometers
Convergence Angle:
     42°