Janssen (Martian crater)

Janssen Crater

Location of Janssen Crater
Planet	Mars
Region	Arabia quadrangle
Coordinates	2°42′N 38°30′E / 2.7°N 38.5°E / 2.7; 38.5Coordinates: 2°42′N 38°30′E / 2.7°N 38.5°E / 2.7; 38.5
Diameter	158 km
Eponym	Pierre Janssen

Janssen Crater is an impact crater in the Arabia quadrangle on Mars at 2.7° N and 322.5° W. and is 158.0 km in diameter, it is also in the north of Terra Sabaea. Its name was approved in 1973, and it was named after Pierre Janssen. Some close up images of the crater reveal layers in a floor deposit. A picture below show these layers, as well as dark slope streaks. The darker the streak, the younger it is. The layers on the floor of Janssen may have been formed on the bottom of lakes.

Nearby prominent and named craters include Teisserenc de Bort crater in the east, Tuscaloosa to the west and the large Tikhonravov for the north. Some tens of kilometers to the west is a valley known as Naktong Vallis.