Earth Has Scores of Mini-Moons, Models Predict
About a thousand unseen objects are in orbit at any time, study says.
What's more, these tiny moons occasionally plummet through our planet's atmosphere, creating brilliant fireballs, the researchers say.
The findings are based on supercomputer simulations of ten million asteroids known to fly through the Earth-moon system. The models show that objects that circle the sun in orbits similar to Earth's are likely to be captured as mini-moons.
(Also see: "Trojan Asteroid Found Sharing Earth's Orbit—A First.")
"We accurately tracked their motion—including the gravitational tugs from the sun and all the other planets and big asteroids in the solar system—and found that 18,000 of [these asteroids] were captured and briefly went into orbit around the Earth," said study co-author Robert Jedicke, an astronomer at the University of Hawaii.
"We estimate that there are
