Tiselius

Tiselius is a lunar impact crater that lies just to the east of Valier, on the Moon's far side. The craters Tiselius and Valier are separated by only a few kilometers. Less than one crater diameter to the east of Tiselius is the smaller, elongated Stein, and to the north is the small, eroded Šafařík.

This is a roughly circular crater with a well-defined edge that has not been significantly degraded by impact erosion. The inner walls have slumped in places to form piles of scree. The interior floor is marked by a few small craterlets, and there is an irregular group of ridges around the midpoint. The small, cup-shaped satellite crater Tiselius E lies near the eastern outer edge.

The crater was named after Swedish biochemist Arne Tiselius, by the IAU in 1979.