Through the north-eastern plains of the Sea of Tranquility, more than 500 km from the Apolo 11 landing site, are two magnificent cracks and almost parallel to the surface of the Moon, both have more than 200 km long.

Rupes and Rima Cauchy (Cauchy escarpment and rille) are so named because the bright Cauchy impact crater 14 km in diameter lying between them. Both features were formed after cooling of the huge lava flows that formed the sea.

As the Earth's crust, the crust of the Moon is capable of being deformed by tension. In some lunar maria, are examples of wrinkles that have arisen as a result of the moon's crust deformation under pressure. But beyond a certain critical degree of compression or tension in rocks, a fault occurs, resulting in failure slopes, ridges and rilles. Some failures can be very deep, as called Straight Wall (Rupes Recta) in Mare Nubium.

The Cauchy area is one of the most fascinating places on the Moon. It includes one of the few large lunar failures, one rille and near a high concentration of domes.

In the attached photo I counted 16 domes - how many can you count in this same wonderful image?

Some of the hemispheric summits are capped, other has a classic central well, most, as Cauchy Omega on the far right - has flattened summits, and Cauchy Tau (left of Omega) has an uneven surface, with a small peak.

Rupes Cauchy is partly rille partly escarpment, and looks a bit more complicated than clean escarpment Rupes Recta or cutting chisel rille Rima Cauchy. Rupes Cauchy begins in the west in a couple of small oval craterlets (visible in a reflector of 150 mm or larger) and several larger craters are along its length. Rupes Cauchy extends east to meet with the border of the Sea of Tranquility where irregularity mountains, and there is no evidence that it crosses the mountains to meet with the little ruined crater Lawrence.

Because so many craters lie along the Rupes Cauchy?

Many of the moon rilles seem compound (at least in part) by chains or craterlets elongated craters. In some cases the original faulting may have instigated fresh attacks of volcanic activity that produced small volcanic vents along the fissure. There is or was certainly a good deal of volcanic activity in the region, many are volcanic domes as already mentioned above.

The Cauchy crater is easily visible in binoculars as a bright spot in high illuminations. Rupes and RIMA Cauchy along with the next two domes are visible on a refractor 60 mm when they are positioned near the terminator at low angles of illumination. At sunrise lunar sun Rupes Cauchy (as Rupes Recta) casts a dark shadow over the plains to the east. At sunset the resource appears as a bright line. The Cauchy Omega summit will require at least one reflector 150mm high magnification in good viewing conditions. This fascinating region has much to show us, simply aber what look!

Source: LPOD / Charles Wood

Moonwatch / Peter Greek

Adaptation and complementation: Avani Soares