Though Pluto may have been demoted from the title of planet to "dwarf planet", NASA's newest mission New Horizons which plans a flyby next summer has sparked new interest in the farthest depths of our very own solar system. And it appears that we may not just stop there. According to a new study published in the journal Monthly Notices of the Royal Astronomical Society, researchers believe that even closer than our Oort cloud we may find at least two more planets circling our Sun far beyond Pluto's vast expanses.

Sparking new interest in the outer limits of our solar system, NASA's New Horizons spacecraft has been on a mission since being launched into space in January 2006. And after nearly a decade of traveling to Pluto, located 4.67 billion miles from Earth, the spacecraft has began engaging in its early phases preparing for a flyby beginning on July 14 of this year. Hoping to gather measurements of high-energy particles streaming from the sun and providing researchers with a new view of the dwarf planet, the plans for New Horizons are significantly large. But the new study published this week reveals that NASA and other international space agencies here on Earth may have more to look at in their upcoming missions.

Based on calculations of large celestial bodies well past Neptune, such as the Kuiper Belt and the Oort cloud, researchers have discovered that 12 so-called "Extreme Trans-Neptunian Objects" (ETNO) show symmetry unexpected in asteroids or other masses. And this leads researchers to believe that some may in fact be small 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," researcher with Complutense University of Madrid, Carlos de la Fuente Marcos says. "We consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto."

As the most plausible explanation for the significant alteration of their data, the study reveals to the researchers and the Royal Astronomical Society that distant bodies may have gravitational influences, which would make them planets or dwarf planets at the least. Though much more research must be done to determine whether or not any of the dozen prospects may be large enough or complex enough to be classified as planets, the researchers are hopeful that they may find celestial masses even larger than some of our current planets, just beyond the outskirts of Pluto.

"If it is confirmed, our results may be truly revolutionary for astronomy," de la Fuente Marcos says.