Tomorrow, a crater on the far side of moon may be the scene of an explosion when part of a rocket crashes into the lunar surface.
If space experts are correct, the rocket section is from a Chinese moon mission, Chang’e 5-T1, which has been orbiting through the solar system since 2014.
Like previous Chinese missions, the spacecraft Chang’e is named after a mythical goddess. According to Chinese folklore, the goddess Chang’e lives on the moon with her companion, a large jade rabbit.
The goddess of folklore may be feeling lonely, as in recent years traffic to the moon has been sparse, but she and her rabbit companion have no shortage of space debris scattered around the lunar surface.
First object from humans crashed onto the moon in 1959.
The moon became the favourite destination for the Soviet Union and United States when the space race started in the 1950s. Dozens of missions were launched by both nations for scientific and national prestige purposes.
The first object of human origin on the lunar surface was the Soviet Luna 2 mission in 1959. Thirteen more Soviet Luna missions impacted the moon until a successful “soft” landing in 1966. During the same period, the United States lunar missions included the Ranger and Surveyor series, which also achieved a controlled landing on the moon in 1966.
By the time the U.S. spaceflight Apollo 11 touched down on the moon at Tranquillity Base in July 1969, there were already dozens of Soviet and U.S. spacecraft scattered around the moon’s surface. Missions from both nations had provided valuable science and images to map the moon — including the far side, which is hidden from Earth’s view.
Each of the six U.S. Apollo missions left behind substantial amounts of debris. More than a dozen scientific instruments were left on the moon, including a seismometer to determine if there are “moonquakes.” Others instruments measured the moon’s magnetic field and the lunar atmosphere.
Only the Lunar Laser Ranging experiment is still working. Scientists on Earth bounce lasers off the device, which is how we know the moon is spinning away from the Earth at the rate of 3.78 cm (1.48 inches) every year.
Each Apollo mission left a large descent stage behind and much more. The astronauts offloaded kit such as geology hammers, experiments and even bags of human excrement to create room for the moon rocks that each mission brought back.
Many astronauts also left personal items, including family photographs. There are three golf balls that Alan Shepard hit during the Apollo 14 mission.
‘I own an an object from a foreign celestial body.’
If you fancy a drive on the moon, there is a pick of vehicles waiting to be dusted off — moon dust is not good for batteries — and charged up.
In 1970, the Soviet Union sent robotic rover Lunokhod 1, which was remotely controlled from Earth to explore and photograph the lunar landscape. The highly successful Lunokhod 2 rover followed in 1973, carrying an array of scientific instruments.
Lunokhod 2 operated for four months, sending back 80,000 images from still and television cameras before driving into a crater. Lunokhod 2 holds the distance record for driving on the moon, as it traversed nearly 40 kilometres on its eight wheels.
The American fleet of three Lunar Roving Vehicles, popularly known as moon buggys, were carried by Apollo 15, 16 and 17 to allow the astronauts a greater range for exploration. The battery-operated vehicles carried two astronauts and their equipment as they explored the landscape. Gene Cernan of Apollo 17 — the last human to stand on the moon — claimed the lunar speed record as he drove 11.2 mph (18.0 km/h).
The Chinese robotic rovers, Yutu 1 and Yutu 2 — named after Jade Rabbit — arrived on the moon in 2013 and 2018. Their high-resolution images and readings from their ground-penetrating radar have provided scientists with more insights about the moon’s surface.
In 1993, the Russian space agency Rocosmos sold the Lunokhod 2 rover at a Sotheby’s auction to Richard Garriott, a wealthy video game developer, for $68,000. “I am now the world’s only private owner of an object on a foreign celestial body,“ Garriott quipped.
Garriott flew in space as a paid “space tourist” when he spent 12 days on the International Space Station. Garriott’s passion may have been inherited from his astronaut father Owen Garrison, who went to space twice on NASA’s Skylab and Space Shuttle.
‘The moon is a handy dump.’
So, does it matter if yet another bit of space debris crashes into the moon?
“It’s no big deal,” said Prof. Don Pollacco of the University of Warwick’s Centre for Space Domain Awareness. “The moon has actually been a handy dump for things like the Apollo spacecraft. Rather than let them float around, most of the first and second stages were crashed into the moon.”
NASA goes further and has called Friday’s predicted crash “an exciting research opportunity.” Their Lunar Reconnaissance Orbiter will be observing the crater that is expected to be created by the impact of the rocket stage.
With several countries now looking in this decade to establish lunar bases for long-term human stays on the moon, maybe the wide range of Earth-produced debris on the moon could be recycled for other purposes. Meanwhile, debris continues to accumulate.