The archives of Space.com have produced an old but strikingly weird story about a strikingly weird discovery – a second moon orbiting invisibly around Earth:
The 3-mile-wide (5-km) satellite, which takes 770 years to complete a horseshoe-shaped orbit around Earth, is called Cruithne and will remain in a suspended state around Earth for at least 5,000 years.
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There are almost certainly more temporary moons of Earth and of other planets waiting to be discovered, Murray said.
As scientists get better at discovering asteroids, they will find more that have orbits that will keep them close to Earth for a long period of time. But some of those objects are very small.
“At some stage you have to consider the definition of moon,” he said. “Is a dust particle orbiting the Earth a moon of the Earth?”
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For now, Namouni says there should be a new category of moons — “temporary moons that are captured for a few thousand to several tens of thousands of years.”
Oh and the name comes from the Modern Irish word for the Picts, and their legendary first chieftain.