Jansky is a lunar impact crater that lies along the eastern limb of the Moon.

[1] It lies due east of the larger walled plain Neper, along the southern edge of the Mare Marginis.

Due to its location, this crater is viewed from the side from Earth, limiting the amount of detail that can be observed.

The southern part of the rim in particular is disrupted and irregular in form, with a pair of small craters along the inner wall.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Jansky.