NASA : Earth has a second, Asteroid mini moon
Well here have something awkward news. Scientists just identified a second, mini-moon orbiting our planet. What? Really? Another moon? Yes! An asteroid mini moon has been orbiting our planet for only around 100 years.
This second moon looks to be a recently captured asteroid. Still, it’s a remarkable event that proves just how dynamic our gravitational relationship is with near-Earth objects. The new moon’s orbit as it bobs up and down like a tiny float in choppy water.
As shown this cool video by NASA path of 2016 HO3 tends to twist and drift over time, but Earth’s gravitational pull keeps the asteroid contained. This asteroid never comes closer than 9 million miles (14.5 million kilometers) to Earth, and it never gets more than 24 million miles (38.6 million km).
Paul Chodas, manager of NASA’s Center for Near-Earth Object (NEO) said
The asteroid’s loops around Earth drift a little ahead or behind from year to year, but when they drift too far forward or backward, Earth’s gravity is just strong enough to reverse the drift and hold onto the asteroid so that it never wanders farther away than about 100 times the distance of the moon. The same effect also prevents the asteroid from approaching much closer than about 38 times the distance of the moon. In effect, this small asteroid is caught in a little dance with Earth.
NASA also reveled that HO3 is approximately larger than 120 feet (40 metres) across and 300 feet (100 metres) wide. So the asteroid is too small that’s why it has taken much time to spot it. Origianlly it is spotted on April 27, 2016 by the Pan-STARRS 1.
The asteroid orbited our world for about a century, and it will stick around for many more centuries.
Source : NASA