For years, researchers have attempted to determine the location of a potential ninth planet, also referred to as Planet X or Planet Nine. However, while scientists continue to move closer to determining the location of Planet Nine, one researcher is exploring the idea that the elusive planet is the cause of Earth's periodic mass extinctions, including the disappearance of dinosaurs.

In a new study, retired astrophysicist Daniel Whitmire claims that that an undiscovered ninth planet stimulates comet showers every 27 million years, which subsequently leads to mass extinctions.

Whitmire and his research partner, John Matese, point to evidence of periodic comet showers in the fossil record that date back to around 500 million years ago as support for their theory.

Back in 1985, when Whitmire proposed a similar explanation for mass extinctions in the journal Nature, there were two major theories that offered alternative explanations for the cause of major comet showers: a sister star to the sun and vertical oscillations of the sun as it orbits the center of our galaxy. Although both of these theories have since been disproved, the theory of a ninth planet has been rapidly gaining ground.

Whitemire claims that periodic comet showers cause violent collisions. Furthermore, he says that those that miss the Earth are destroyed in the inner solar system and cool the planet by dimming the sun's solar energy.

Although no conclusive evidence of his theory has yet to surface, Whitmire is hopeful that future studies will reveal more about Planet Nine and shed light on the evolution of our planet and the solar system that it resides in.

"I've been part of this story for 30 years," he said. "If there is ever a final answer I'd love to write a book about it."

Recent research is examining objects in the Kuiper Belt, a mysterious ring-shaped region of comets and other icy objects, for evidence of Planet Nine. Current results suggest that Planet Nine is influencing these objects and causing anomalies in their orbits, prompting scientists to use information on these anomalies to attempt to pinpoint the location of the mysterious planet.

The findings were published in the Jan. 1 issue of the Monthly Notices of the Royal Astronomical Society.