Lunar impacts are not a new phenomenon

Lunar impacts are not a new phenomenon. For more than 60 years, space organizations have smashed spacecraft onto the moon to either destroy them or examine the craters they leave behind. The moon is also pocked by natural impact craters, believed to number in the millions. According to the European Space Agency, Friday’s accident is the first unintentional impact of human-made debris on the lunar surface.

Space debris is frequent 

Closer to our planet, space debris is frequent, according to NASA, 36,500 pieces of trash are more significant than 4 inches in Earth orbit. However, the approaching hit has been dubbed “a harbinger” by Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics who maintains track of space debris. As a result of this approaching transition, some astronomers are asking for a new era of space environmentalism. The final frontier is afforded the same protections as terrestrial habitats.

• After a launch, rocket boosters or upper stages may end up in orbit around the sun or fall back to Earth, where they will burn up when they re-enter the atmosphere. However, leftover rocket pieces occasionally meander into higher, extended orbits around the Earth and cross paths with the moon, as appears to be the case here.
• “People have thrown garbage into higher orbits of this sort and simply forgotten about it,” said Bill Gray, an astronomer with Project Pluto. This Maine-based organization provides software for tracking near-Earth object paths.
• The coming lunar impact was initially announced by Mr. Gray. After observations revealed that an object he had initially seen moving between Earth and the moon in 2015 had returned to the vicinity, he did so in late January.
• Initially, we assumed the rocket was a SpaceX Falcon 9 booster that had launched an Earth monitoring satellite seven years ago. However, data from NASA’s Jet Propulsion Lab revealed that the spacecraft’s original trajectory—which Mr. Gray spotted in 2015—didn’t get it close enough to the moon to match the SpaceX launch.
• Mr. Gray later clarified in mid-February that the debris in issue was a leftover booster from a Chinese rocket that launched the Change-5 T1 spacecraft in 2014.
• Mr. Gray’s re-identification of the object has now been confirmed by astronomers from the University of Arizona and NASA. According to a NASA official, the Lunar Reconnaissance Orbiter would study the impact location.