Forget exoplanets

School-aged children the world over collectively tweeted “WTF” in November 2010, when two astronomers announced that they think there could be a previously undiscovered planet orbiting out in the distant reaches of the solar system, past Pluto.

The astronomers, John Matese and Daniel Whitmire, published their paper “Persistent Evidence of a Jovian Mass Solar Companion in the Oort Cloud” in the journal Icarus and based their findings on how comets behave. They stated that “the results [of their analysis] support a conjecture that there exists a companion [ . . . ] in the innermost region of the outer Oort cloud.”

The Oort cloud is an immense cloud of icy objects that extends from about one to three light years out from the sun. It is a source of comets.

Matese and Whitmore propose that the planet, which they have named “Tyche,” is approximately four times more massive than Jupiter and may be a star that failed to ignite — also known as a “brown dwarf” star.

If you’re wondering how a whole planet — especially one four times more massive than Jupiter — goes unnoticed for all of human history, the reason is that the Oort cloud is really far away, lying about one light year (or nine trillion kilometres) farther from the sun then the earth. At this distance Tyche would be invisible to all but the most sophisticated infrared telescopes.

Luckily NASA’s Wide-field Infrared Survey Explorer (WISE) just completed a detailed survey of the Oort cloud and is set to release preliminary results as soon as April 2011, with the bulk of the data coming in March 2012.

According to NASA, it is “likely” that if Tyche is out there, WISE will find it. Although they caution that it is not a “foregone conclusion.”

In the meantime, astronomy buffs, school children and textbook publishers will be holding their breath.