Armstrong is a tiny lunar impact crater located in the southern part of the Mare Tranquillitatis

Mare Tranquillitatis

Mare Tranquillitatis is a lunar mare that sits within the Tranquillitatis basin on the Moon. The mare material within the basin consists of basalt formed in the intermediate to young age group of the Upper Imbrian epoch. The surrounding mountains are thought to be of the Lower Imbrian epoch, but...

. It lies about 50 kilometers to the northeast of the Apollo 11

Apollo 11

In early 1969, Bill Anders accepted a job with the National Space Council effective in August 1969 and announced his retirement as an astronaut. At that point Ken Mattingly was moved from the support crew into parallel training with Anders as backup Command Module Pilot in case Apollo 11 was...

 landing site. Named after Neil Armstrong

Neil Armstrong

Neil Alden Armstrong is an American former astronaut, test pilot, aerospace engineer, university professor, United States Naval Aviator, and the first person to set foot upon the Moon....

, the crater is the eastern-most of the row of three craters named in honor of the Apollo 11 crew members. To the north is the Ranger 8

Ranger 8

Ranger 8 was a spacecraft designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. The spacecraft carried six television vidicon cameras, two wide angle and four narrow angle to accomplish these...

 impact site.

This crater was previously identified as Sabine E before being renamed by the IAU

International Astronomical Union

The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

. Sabine

Sabine (crater)

Sabine is a lunar crater that forms a nearly matching pair with Ritter to the northwest. The two rims are separated by a distance of only a couple of kilometers. To the west is the bowl-shaped crater Schmidt, and farther to the north are Manners and Arago....

itself is located due west of Armstrong.