Delete Your Orbit: Earth’s Potentially Nefarious Stalker
published during a waxing crescent moon.

Potentially Nefarious Stalker

Honestly though, how neat can it really be? It’s that totally distinctive looking dot circled by green near the bottom, in case you were wondering. Credit: NASA/JPL-Caltech

Delete Your Orbit is a recurring column on NOW.SPACE that provides well-informed, but alarmingly petty analyses of various objects in our universe. 

Back in 2011, people got fairly jazzed about the discovery of a tiny, errant asteroid named 2010 TK7 that is currently latched onto Earth’s orbit much like a hookworm to a mammal’s intestines.  It was an exciting find, they said, because it was the first “trojan” to be discovered in Earth’s orbit. A trojan, they reminded us, is an object that shares the orbit of another object (without actually orbiting around that object) through a weird loophole carelessly introduced by whatever came up with the laws of orbital mechanics.

First things first: This sneaky creeper has been hiding from us.

To those fairly jazzed people, I say this: do not trust 2010 TK7. Like the mythic wooden horse also named after that ancient city of Troy, this object may appear to be kind of neat at first glance, but we have no way of knowing if it will become an insidious trap orchestrated by distant, foreign forces.

First things first: This sneaky creeper has been hiding from us. The gravitationally stable point in Earth’s orbit that 2010 TK7 awkwardly hovers around in is just a bit ahead of Earth in its orbit, and its placement conveniently forces us to look directly into the sun to see it pretty much all the time—taunting us, ironically, with the protection of blinding light. It was a pretty solid plan, and 2010-TK47 might have remained undetected had a pesky telescope named WISE not caught a glimpse the trojan creeper when it meandered a bit too far away.

The fact that Earth, a respectable terrestrial planet which has been housing sentient life for hundreds of millions of years, has been following behind a pitiful space pebble (it’s about 1000 feet in diameter) for who knows how long, is insulting. “It’s as though Earth is playing follow the leader,” said Amy Mainzer, the principal investigator of the mission that searched for this trojan, back at the time of its discovery. Earth should follow no asteroid, especially one whose history and future intentions are so opaque.


A video showing 2010 TK7 creeping around ahead of Earth’s orbit. Credit: Athabasca University/CFHT

Because of its primo hiding spot, we pretty much have no idea what 2010 TK7 looks like—its color and its shape remain unknown. Luckily, trojans are in no way special or rare in our solar system—Jupiter has over 5000 of them, and Neptune and Mars both have many as well. It presumably just looks like an asteroid—probably a boring one—like most of the other ones out there.

The most troubling unknown about 2010 TK7, though, is that we don’t even really know its future trajectory. Chaos theory dictates we have confidence only in predictions about 2017 TK7’s orbit 250 years into the future. For an object in space whose behavior is dictated by only one law—gravity—to have a future that is so uncertain should be a red flag. That something called “chaos theory” is the cause of this ambiguity does not help 2010 TK7’s case at all.

Potentially Nefarious Stalker

An image depicting the absurd orbit of 2010 TK7. Credit: Paul Wiegert, University of Western Ontario, Canada

This uncertainty plays into the trojan’s most nefarious trait of all—that its future orbit may be dictated not by the benevolent Earth, but instead by the massive solar system overlord that is Jupiter. Jupiter is so large, and 2010 TK7’s mass so minuscule, that it may end up having a pretty serious influence on it. Yes, it is currently attached to our orbit. Yes, we know it could potentially remain there for a very long time. But Jupiter also has the ability to push or pull it in a myriad of other directions and orbits, and its gravitational pull has the potential to be 80 times more powerful than Earth in certain orbital configurations.

Do we really want a creepy and mysterious Jovian agent as an orbital companion? It’s time to stop being jazzed and start getting angry.

TL;DR: 2010 TK7, a glorified lost asteroid, is a freeloading potential agent of Jupiter that is not to be trusted.