Solar System’s “Planet X” Returns!

30 04 2010

Researchers propose new planet "Tyche" on distant fringe of solar system. Inner planets on this diagram are too close to the Sun to see. (Credit: Ben McGee)

Our solar system may have just gotten a lot more interesting. Researchers studying the orbits of comets at the University of Louisiana have found a problem.  -They’ve discovered an inconsistency with how comets are spread out compared to what you would expect under ordinary galactic conditions.  In an article recently submitted to the journal Icarus, they propose the existence of another behemoth planet orbiting far beyond Pluto along the outskirts of the Oort Cloud (a huge sphere of proto-comets  that surrounds the solar system) and that this proposed planet, Tyche, is responsible for what they see.

This calls to mind another similar hypothesis based on the apparently cyclical nature of mass extinctions throughout Earth’s history and on geologic evidence from the Moon.  Called the Nemesis theory, it proposes that our solar system is actually a binary star system, and that the Sun’s twin is a small, dim, red dwarf star named Nemesis orbiting far beyond the Oort cloud.  As the theory goes, Nemesis passes close enough to the Oort cloud to send a deadly rain of comets into the inner solar system every few-score-million years or so.  The name here is completely appropriate, as those familiar with Greek Mythology will recall that Nemesis is the goddess of Retribution.

While the Tyche and Nemesis models are clearly different proposals, the researchers offering the new proposal are aware of the similarities.  According to Greek Mythology, Tyche is Nemesis’s good sister, the goddess of Fortune and Luck.  Say what you will about the penchant of astronomers to lean on mythology – I think it’s clever.

With all of these findings hinting at something going on in the outer solar system, it seems as though there’s something there to find.  A cold gas giant would be fascinating, as would the revelation that our Sun has had a twin all along.

Maybe even both.


%d bloggers like this: