Lat: 10.0°S, Long: 18.0°W, Length: 40 km, Height: km, Rükl: 42
AS16-M-2207 This small area in the western part of Mare Cognitum contains a number of wrinkle ridges, only one of which has an official IAU name. The large crater visible in the upper right is Bonpland. The two prominent craters near the bottom are 6-km Bonpland D (left) and 4-km Bonpland C (right). Judging from the position and diameter listed in the IAU Planetary Gazetteer, Dorsum Guettard is the ridge running northwest from Bonpland C towards Bonpland D and the first part of the shadowed ridge extending northwest out of Bonpland D. In this photo, the latter ridge appears to continue north to a point where it blends into the glacis around Bonpland, but this continuation is well outside the range of the stated feature diameter. However, the original IAU approval was actually of the feature as labeled on LTO 76C1, and those labels included the northward extension as well as a short extension to the east of Bonpland C (going slightly outside the present frame). It is unclear which definition is current. Note: the spiral pole with the brush-like tip on the right is a boom on the Apollo 16 Command Module (from whose "SIM" bay this photo was taken).
- There's only one orbital Hasselblad photograph of the southern part of Dorsum Guettard and Bonpland D, made during the mission of Apollo 16. This photograph is AS16-120-19243 (Magazine V, color).
- The curious crater Bonpland D is also mentioned in APOLLO OVER THE MOON: A VIEW FROM ORBIT Chapter 7: Unusual Features (Part 2), Figure 246, Itek panoramic image AS16-P-5429.
- Jean-Etienne; French geologist, mineralogist (1715-1786).
- This name was provisionally introduced on LTO 76C1 where the entire ridge was labeled. This name was among those approved by the IAU in 1976 (IAU Transactions XVIB) "as now assigned and printed" on the LTO charts. Howevere, as noted above, the position and dimension given in the on-line IAU Planetary Gazetteer appears to make the name apply to only a part of it. - Jim Mosher