Naonobu (crater)
Apollo 15 image  | |
| Coordinates | 4°36′S 57°48′E / 4.6°S 57.8°E | 
|---|---|
| Diameter | 34 km | 
| Depth | Unknown | 
| Colongitude | 302° at sunrise | 
| Eponym | Naonobu Ajima | 
Naonobu is a small lunar impact crater named after Japanese mathematician Ajima Naonobu. It is located on the eastern Mare Fecunditatis, to the northwest of the prominent crater Langrenus, and it forms a triple-crater formation with the adjacent Atwood to the south and Bilharz just to the southwest. Naonobu and Atwood are separated by only a few kilometres.
The interior of this crater has been flooded with basaltic lava, leaving a relatively flat interior and a reduced outer rim. There is no central peak, but a small crater lies just to the southwest of the midpoint. A similar crater lies across the western interior of the rim.
This crater was previously designated Langrenus B before being renamed by the IAU in 1976.