The concept of Earth’s “mini-moons” refers to small asteroids temporarily captured by Earth’s gravity, orbiting the planet for a limited time before either entering the atmosphere or escaping back into space. There has been speculation about whether these objects originate from the Moon, potentially being chunks ejected by lunar impacts. However, the majority of mini-moons are believed to be captured near-Earth asteroids rather than lunar fragments.
To determine the origin of such a mini-moon, scientists analyze its trajectory, speed, and surface composition. A detailed spectroscopic analysis can compare the mini-moon’s surface to known lunar samples. If a mini-moon shared compositional similarities with the Moon’s surface, it could suggest a lunar origin. Nevertheless, given the vast array of materials in space and the variety of near-Earth objects, most captured mini-moons are thought to be independent asteroids rather than lunar pieces.
In summary, while the idea of a mini-moon being a fragment of the Moon is intriguing, it remains more probable that they are ordinary asteroids. Advanced observations and sample-return missions in the future may provide more conclusive evidence.