1) GR kirchhoff 2) German surname 3) Gustav robert kirchhoff 4) Physicist 
[crater] This is a circular, bowl-shaped feature that lies in the midst of rugged lunar terrain. The satellite crater Kirchhoff C adjoins the eastern rim. There is a low rise at the midpoint of the interior floor. ==Satellite craters== By convention these features are identified on lunar maps by placing the letter on the side of the crater ...
[n] - German physicist who with Bunsen pioneered spectrum analysis and formulated two laws governing electric networks (1824-1887)
1824–87, German physicist.