Last week during the 49th Annual Division for Planetary Science Meeting at Provo in Utah, one of the planetary astronomers, Vishnu Reddy, from the University of Arizona Lunar and Planetary Laboratory, unveiled new data of an object that was discovered in 2016. The object was spotted to be moving with Earth around the sun.
While many suspected the object to be a space junk, Reddy's data confirmed that the object, called 2016 HO3, is actually an ordinary asteroid and that too, a small one. However, there is a difference. Unlike most of the space asteroids that move past Earth continually, 2016 HO3 isn't moving past the Earth. It's actually traveling with us.
Reddy and his team made use of the world's largest telescopes – the Large Binocular Telescope (LBT) on Mt. Graham in southeastern Arizona to learn more accurately about our space companion, reports a blog post from LBT observatory.
"2016 HO3 is a small near-Earth object (NEO) measuring not more than 100 meters (330 feet) across that, while orbiting the sun, also appears to circle around the Earth as a quasi-satellite. Only five quasi-satellites have been discovered so far, but 2016 HO3 is the most stable of them. The provenance of this object is unknown. On timescales of a few centuries, 2016 HO3 remains within 38 to 100 lunar-distances from us," the blog post noted.
The post further stated that "in an effort to constrain its rotation period and surface composition, we observed 2016 HO3 on April 14 and 18 with the Large Binocular Telescope and the Discovery Channel Telescope. The derived rotation period and the spectrum of emitted light are not uncommon amongst small NEOs, suggesting that 2016 HO3 is a natural object of similar provenance to other small NEOs."
Observations also revealed that HO3 rotates once every 28 minutes and is made of materials similar to usual asteroids.
"One way to visualize HO3's orbit is by picturing a hula hoop dancer — the sun in this analogy — twirling two hoops around the hips at the same time, ever so slightly out of sync. While it orbits the sun, the object makes yearly loops around the Earth. As a result, the object appears to orbit the Earth, but it is not gravitationally bound to our planet," states the post.
So, the conclusion is that the Earth's quasi-satellite 2016 HO3 is, indeed, an asteroid and not just another space junk.