Uranus Has a Long-Lost Twin

Uranus has always been a pretty lonely planet. The seventh planet from the Sun, this "ice giant" made primarily of ice particles, hydrogen, and helium is relatively unique, drifting around our solar system in an unusual elliptical orbit at a stunning 99 degrees axial tilt. Now, however, researchers are saying that the baby-blue planet has an unlikely twin 25,000 light-years away.

That's at least according to a study recently published in The Astrophysical Journal, which details how there is another part-gas ice planet about the same size as Uranus and with the same unusual elliptical orbit.

And although axis tilt and exact composition of the planet cannot be determined with it being so far away, astronomers are confident enough in their measurements to call it Uranus's "twin."

So what's the big deal? There are likely a lot of ice giants floating around the Universe that are like Uranus, never mind our own solar system's other gas planets.

However, Andrew Gould of Ohio State University says that we are fortunate to have a twin as close as this one is, because it gives astronomers a rare opportunity to compare and contrast, potentially learning more about how ice giants form in solar systems like ours.

"Nobody knows for sure why Uranus and Neptune are located on the outskirts of our solar system, when our models suggest that they should have formed closer to the Sun," Gould said in a statement, highlighting one of the mysteries he and his colleagues hope to solve. "One idea is that they did form much closer, but were jostled around by Jupiter and Saturn and knocked farther out."

Interestingly, the Uranus twin looks to have gone through a similar jostling, as it can be found in a binary star system. While it orbits one star, the astronomers observed that its orbit is affected by the pull of a second nearby star.

"Maybe you need some kind of jostling to make [ice giants] like Uranus and Neptune," Gould suggested.