Jansen is a lunar impact crater in the north part of the Mare Tranquillitatis. The diameter is 24 km. It was named after 17th century Dutch optician Zacharias Janssen.[1] It is located to the east-southeast of the crater Plinius. The rim of Jansen is low and narrow, with a notch along the western edge. The interior is relatively level, which may indicate it has been covered by lava. To the south-southwest a small but prominent crater lies on the crater floor, halfway between the center and the rim.
Coordinates | 13°30′N 28°42′E / 13.5°N 28.7°E |
---|---|
Diameter | 24 km |
Depth | 0.6 km |
Colongitude | 351° at sunrise |
Eponym | Zacharias Janssen |
To the northwest of the rim is a rille named Rima Jansen, and to the east are wrinkle ridges in the mare surface. A low ridge runs from near the southeast rim in a southeasterly direction.
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Jansen.
Jansen | Latitude | Longitude | Diameter |
---|---|---|---|
D | 15.7° N | 28.4° E | 7 km |
E | 14.5° N | 27.8° E | 7 km |
G | 9.3° N | 26.0° E | 6 km |
H | 11.4° N | 28.4° E | 7 km |
K | 11.5° N | 29.7° E | 6 km |
L | 14.7° N | 30.1° E | 7 km |
R | 15.2° N | 28.8° E | 25 km |
T | 11.4° N | 33.5° E | 5 km |
U | 11.9° N | 32.3° E | 4 km |
W | 10.2° N | 29.5° E | 3 km |
Y | 13.4° N | 28.6° E | 4 km |
The following craters have been renamed by the IAU.