Image courtesy Caltech/ASU/NASA

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This illustration shows the final flight path for NASA's twin Gravity Recovery and Interior Laboratory (GRAIL) mission spacecraft, which crashed into the moon December 17, 2012.

Image courtesy Caltech/ASU/NASA

GRAIL Mission Goes Out With a Bang

The twin probes aren’t the first to crash into the moon.

On Friday, December 14, NASA sent their latest moon mission into a death spiral. Rocket burns nudged GRAIL probes Ebb and Flow into a new orbit designed to crash them into the side of a mountain near the moon's north pole today at around 2:28 p.m. Pacific standard time. NASA named the crash site after late astronaut Sally Ride, America's first woman in space.

Although the mountain is located on the nearside of the moon, there won't be any pictures because the area will be shadowed, according to a statement from NASA Jet Propulsion Laboratory in California.

Originally sent to map the moon's gravity field, Ebb and Flow join a long list of man-made objects that have succumbed to a deadly lunar attraction. Decades of exploration have left a trail of debris intentionally crashed, accidentally hurtled, or deliberately left on the moon's surface. Some notable examples include:

Ranger 4 - Part of NASA's first attempt to snap close-up pictures of the moon, the Ranger program did not start off well. Rangers 1 through 6 all failed, although Ranger 4, launched April 23, 1962, did make it as far as the moon. Sadly, onboard computer failures kept number 4 from sending back any pictures before it crashed. (See a map of all artifacts on the moon.)

Fallen astronaut statue - This 3.5-inch-tall aluminum figure commemorates the 14 astronauts and cosmonauts who had died prior to the Apollo 15 mission. That crew left it behind in 1971, and NASA wasn't aware of what the astronauts had done until a post-flight press conference.

Lunar yard sale - Objects jettisoned by Apollo crews over the years include a television camera, earplugs, two "urine collection assemblies," and tools that include tongs and a hammer. Astronauts left them because they needed to shed weight in order to make it back to Earth on their remaining fuel supply, said archivist Colin Fries of the NASA History Program Office.

Luna 10 - A Soviet satellite that crashed after successfully orbiting the moon, Luna 10 was the first man-made object to orbit a celestial body other than Earth. Its Russian controllers had programmed it to broadcast the Communist anthem "Internationale" live to the Communist Party Congress on April 4, 1966. Worried that the live broadcast could fail, they decided to broadcast a recording of the satellite's test run the night before—a fact they revealed 30 years later.

Radio Astronomy Explorer B - The U.S. launched this enormous instrument, also known as Explorer 49, into a lunar orbit in 1973. At 600 feet (183 meters) across, it's the largest man-made object to enter orbit around the moon. Researchers sent it into its lunar orbit so it could take measurements of the planets, the sun, and the galaxy free from terrestrial radio interference. NASA lost contact with the satellite in 1977, and it's presumed to have crashed into the moon.