'Our Moon was stolen?': The shocking new theory that could rewrite space history
Produced by: Mohsin Shaikh
Unique Duo
Earth and its Moon are a rare pair in the Solar System. Unlike other planets with multiple moons or none at all, Earth's single, hefty moon sets it apart, making our planetary relationship unique.
Unusual Origin
The Moon’s origin remains a mystery. While some believe it was formed from the same material as Earth, new research suggests it might have been captured from elsewhere in the Solar System.
Adopted Moon?
Astronomers Darren Williams and Michael Zugger claim the Moon could be an "adopted" body, originally born elsewhere and later captured by Earth's gravity in a rare event.
Gravitational Capture
The study from Pennsylvania State University calculates that Earth could have captured a Moon-sized object through a process called binary capture, where two celestial bodies pass by and one is "stolen."
Moon's Odd Orbit
The Moon’s orbit around Earth isn’t perfectly aligned with the equator, a detail that hints at a more complex origin story than previously thought, possibly challenging the widely accepted Giant Impact Hypothesis.
Giant Impact Theory
The prevailing theory suggests the Moon formed from debris after a large object collided with Earth. This explains the mineral similarities between Earth and the Moon, though new research raises questions.
Binary Capture Hypothesis
This hypothesis suggests that Earth might have captured the Moon through a three-body interaction, where a passing third body helps "snare" the Moon from another gravitational pair.
Triton’s Clue
Neptune’s moon Triton, which orbits in the opposite direction from other moons, is thought to have been captured from the Kuiper Belt. This lends credence to the idea that Earth could have captured the Moon.
New Research, New Questions
Published in The Planetary Science Journal, this research opens new avenues for understanding planetary systems. As Williams notes, “We now have two possibilities for how the Moon got here,” sparking fresh questions for future study.