The myth of Planet X

Steph P. Bianchini January 20, 2015 1 Comment

…which is maybe not a myth after all.

When I have written some time ago about Nemesis, or the Death Star, in fiction and in conspiracy theories, I have briefly mentioned Planet X. Historically, this name has been given to two different celestial objects. The first one is a mysterious (and truly unlikely) planet located on the LP (which stays for Lagrangian Point) 3 of the Sun-Earth orbit.

However, since LP3 is a point that remains constantly hidden behind the Sun, a hypothetical planet located there would be invisible from Earth. Guess what? SF writers and conspiracy theorists have long speculating about the existence of  a Counter-Earth over there. Have a look at The Illuminatus! Trilogy or at Antigeos series of novel of Paul Capon, just to mention famous cases (in case you’re hungry for more, this one is a good initial list ).

Why is this unlikely? Well, the problem is that LP3 is really unstable. And when I say really, I mean it. Even if a planet was by some bizarre reasons situated there, it would have not remained in that position for long. How long? 150 years, give or take, before getting into trouble. Have a look at this one for a mathematical demonstration by NASA, and, if you’re interested in Lagrangian Points in science and fiction, you can find some more references in my articles (part one and two) about them.

The other,  more scientifically plausible, is a planet orbiting the Sun in the outer Solar System, i.e., after Pluto. In this case, X refers not to the unknown term x but to the numeral (X like ten in Roman numbers, after Pluto that would be the ninth one, controversies permitting).

Long considered another myth, the existence of a tenth planet seems having instead some ground. The hint has come recently from the analysis of some ETNOs (Extreme Trans-Neptunian Objects), whose orbits look affected by some unknown external forces. Like planets.

“This excess of objects with unexpected orbital parameters makes us believe that some invisible forces are altering the distribution of the orbital elements of the ETNO and we consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto.The exact number is uncertain, given that the data that we have is limited, but our calculations suggest that there are at least two planets, and probably more, within the confines of our solar system.”  (Carlos de la Fuente Marcos, scientist at the University Complutense of Madrid).  So, not just Planet X, but Planet Y too. Maybe (just maybe) New Horizons, en route for its Pluto’s flyby in July 2015, will help shedding some light.

The quest for Planet X in the sense of the outer planet has been long ongoing, and popular culture reflects it as well. And not just in the Western culture. As a kid, I remember watching a Japanese anime called Danguard Ace (惑星ロボ ダンガードA -エー), created, like Captain Harlock and Galaxy Express 999 by Leiji Matsumoto and where spaceships from Earth leave to colonise the Tenth Planet, called Promete (from Prometheus).

Planet X also figures in the old American-Japanese movie, The Invasion of Astro-Monsters or Kaijū Daisensō (怪獣大戦争), back to 1969. If I remember well, however, nothing was said about its location in space. Finally, I have been told by a Japanese friend that even Sera Myu (セラミュ), i.e. the Japanese Sailor Moon musicals, have portrayed a Counter-Earth, but I was not able to find any reference to that. In case you know of any additional Asian reference to Planet X, not just from Japan, please do let me know.