Did you know the Earth has had a”Mini-moon” orbiting for past 100 years?


The moon has been getting a lot of attention lately, especially with the rare “supermoon” that is about to occur this Monday, November 14th. We’ve grown up knowing and learning about Earth’s cratered satellite, but did you know that a second moon has been found orbiting our planet?

NASA and our “second moon”

NASA has confirmed that a tiny asteroid, officially named HO3, may have been orbiting Earth for over a century. It is currently unknown exactly how big this tiny “moon” is, but what scientists do know is that it is around 40 meters across and 100 meters wide. Not quite sizeable enough to create the apocalypse if it decided to alter its path to crash course our pretty blue planet.

Fortunately for us, this asteroid will not doom us all. HO3 never gets closer than 38 times the distance of the moon. And due to Earth’s gravitational pull, it never quite makes it past 100 times the distance of the moon either.

It’s Discovery

Our second “moon” was discovered by Pan-STARRS 1 asteroid survey telescope located in Haleakala, Hawaii on April 27, 2016.  The orbit of HO3 is highly elliptical and spends about half its time closer to the sun than Earth and passes ahead of our planet. It spends its other half of the time farther away, causing it to fall behind. Its orbit is also tilted a little, causing it to bob up and then down once each year through Earth’s orbital plane.

This asteroid makes it around the sun every 365.93 days, which is slightly longer than Earth’s 365.24 day orbit around our star. It looks like this quasi-satellite will be stuck with us for centuries to come. Watch this awesome video created by NASA that demonstrates exactly how this mini-moon orbits our earth:

[embedyt] http://www.youtube.com/watch?v=SbbAnVU4rmY[/embedyt]