Ritchey

Ritchey may refer to:

Ritchey (lunar crater)

Ritchey is a small lunar impact crater situated to the east of Albategnius in the central lunar highlands. Its somewhat angular rim is broken along the northwestern wall by a pair of smaller, adjacent craters. The floor of Ritchey is fairly flat, with a pair of small central mounds.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the satellite midpoint that is closest to Ritchey.

References

Ritchey (Martian crater)

Ritchey Crater is a crater in the Coprates quadrangle on Mars, located at 28.8° South and 51° West. It is 79 km in diameter and was named after George W. Ritchey, an American astronomer (1864-1945). There is strong evidence that it was once a lake.

It formed later than the Noachian period. Pictures form HiRISE show that the central peak has massive bedrock and megabreccia with large clasts.

Western side of Ritchey Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter).

Western side of Ritchey Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter).

Fan along western wall of Ritchey Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of previous image.

Fan along western wall of Ritchey Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of previous image.

Ritchey Crater is interesting to scientists because it displays several different layers. A dark layer at the top forms a cap rock that protects the underlying layers from erosion. Under this hard, dark layer is a softer, light-toned rock, that breaks into small boulders. The layers might be formed of volcanic ash, lake or stream deposits, or sand dunes. Fluvial channels and fan deposit are common on and along the walls.