Named after Robert J. Helberg - American aeronautical engineer (1906-1967).
Helberg is a lunar crater that is located just behind the western limb , on the far side from the Earth. Due to libration this part of the surface is sometimes brought into view, and the crater is visible under suitable lighting conditions. However even under these circumstances the crater is viewed from the edge and not much detail can be seen. This crater is nearly attached to the east-northeastern rim of the crater Robertson. (wikipedia entry)