Astronomers don’t have direct evidence to prove that solar system has nine planets, and not eight. But, they believe ‘Planet Nine’ could be hiding in dark hurtling around the cosmos. Now, Cassini spacecraft is going to help scientists search the distant world in dark abyss of the outer solar system.

NASA’s Cassini probe, which has been studying Saturn and its natural satellite since 2004, is currently hunting for ninth planet in solar system’s dark regions. Major challenge astronomers are facing while looking for the Planet Nine is the enormous length of a year for the planetary body. Usually, they take two photographs of a space object at different period of time, but in the case of the Planet Nine, they don’t have any image of it.

Last month, a pair of Caltech astronomers announced that they found clues indicating that a previously-unseen planet is orbiting far beyond eighth planet Neptune. The astronomers, Mike Brown and Konstantin Batygin, believe if scientific community continues its efforts to search for the distant world, it will be observed within five years.

For the last more than 150 years, scientists have used a planetary body’s position to gather information on another planet’s existence, “It was the search for this alleged planet that led to the inadvertent discovery of Pluto, which is why the New York Times headline on the day of the Pluto announcement suggests that the planet might be bigger than Jupiter, which it is not”, said Mike Brown, a professor of planetary astronomy at Caltech and an astronomers who proposed the existence of Planet Nine.

NASA’s Juno spacecraft is scheduled to arrive at gas giant Jupiter in July this year, and astronomers have planned to use data from the probe to search for Planet Nine.