The Earth Has a Second Moon? NASA Says Yes.

By Published on June 17, 2016

National Aeronautics and Space Administration (NASA) astronomers announced Wednesday they discovered a small asteroid in orbit around Earth, acting as the planet’s second moon.

The newly discovered asteroid, dubbed 2016 HO3, orbits the sun in such a way that the space rock never strays too far from Earth, making it a “quasi-satellite” of our planet, scientists say. The asteroid’s exact size is unknown, but researchers believe that it is between 130 feet and 330 feet wide.

“Our calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth’s companion for centuries to come,” Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies at the Jet Propulsion Laboratory, said in a statement Wednesday. “One other asteroid — 2003 YN107 — followed a similar orbital pattern for a while over 10 years ago, but it has since departed our vicinity. This new asteroid is much more locked onto us.”

The asteroid poses no threat to earth, and never gets closer than 9 million miles to our planet. In comparison, Earth’s larger moon is an average distance of a quarter-of-a-million miles away.

The asteroid was first spotted on April 27, 2016, by the Pan-STARRS 1 asteroid survey telescope on Haleakala, Hawaii. This telescope is operated by the University of Hawaii’s Institute for Astronomy and funded by NASA’s Planetary Defense Coordination Office.

Globally, asteroid detection programs have found more than 13,500 near-Earth objects of all sizes.  Roughly 1,500 new near-Earth objects are found every year. Approximately 953 near-Earth objects have already been found this year, according to the Minor Planets Center.

NASA estimates that more than 90 percent of “world-killer” asteroids with a diameter of more than 3,000 feet have already been discovered. The agency is now focused on finding objects that are 450 feet in diameter or larger, which could devastate a city or country if they struck Earth.



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