Watch Apollo Astronauts Falling Over on the Moon

With the 50th anniversary of the Apollo 11 moon landings approaching, images and videos of NASA astronauts gracefully conducting experiments on the lunar surface are being widely circulated. However, it's important to remember that these moonwalks didn't always go smoothly, as archive video from the space agency showing astronauts falling over demonstrates.

These mishaps are not surprising given the difficulty of maneuvring wearing a heavy spacesuit in a low gravity environment, a very different experience to moving around on Earth. Largely, this is down to the fact that while the astronauts weigh less on the moon, their mass is the same as it is on Earth. This means that as they move, their inertia can sometimes be hard to control, Science Alert explained.

While the videos are humorous, they have scientific value for NASA, enabling researchers to study lunar gravity and how humans move in these environments. In fact, NASA created several reports about the Apollo moon missions that include information on each time that an astronaut fell over.

"During the Apollo 15 lunar EVAs [extravehicular activities] there were instances where the astronauts momentarily lost their balance and sometimes even fell," one of the reports read. "The purpose of this analysis is to determine the characteristics of such falls—and near-falls as well—and to identify the specific reasons for their occurrence."

The authors of this paper then describe in detail a number of incidents where the astronauts lost their footing while conducting moonwalks.

"This fall occurred at GMT 214:11:06:28 during the third lunar EVA. CDR [Commander David] Scott and LMP [Lunar Module Pilot Jim] Irwin are at Station 9A describing the area and Scott is taking photographs," the report read. "The CDR begins moving toward a new area as he gives the camera reading and summarizes the description of the area."

"He steps around a group of rock fragments and then his right foot steps into a small depression and he begins to lose his balance. As he steps with his left foot, it slides off a small rock and continues sliding on the loose surface soil," the authors wrote. "While trying to drive his feet back under his center of gravity, Scott increases his forward velocity. He then falls forward with both hands extended to break the fall. Landing on his left side, he rolls counterclockwise and on his back and is then out of view of the TV camera."

With NASA setting its sights on a return to the moon in the coming decade, information such as this may prove to be useful in preparing astronauts to walk on the lunar surface again.

Apollo 15, moon, James Irwin
American astronaut James Irwin saluting the Stars and Stripes at Hadley Base on the Moon during the Apollo 15 mission. Keystone/Getty Images