A new study by scientists at the University of Toronto suggests that Jupiter may have ejected another planet from the solar system about four billion years ago, Hindustan Times reports.
The study was published in the Astrophysical Journal.
The existence of a fifth giant gas planet at the time of the solar system's formation was first proposed in 2011, researchers said.
"Our evidence points to Jupiter," said Ryan Cloutier, a PhD candidate in University of Toronto's Department of Astronomy & Astrophysics and lead author of the new study.
Scientists say that planet ejections occur when planets come too close to each other and one of the objects accelerates so much that it breaks free from the gravitational pull of the Sun.
However, the present study can be distinguished from earlier studies in that it also considers the effect of such encounters on minor bodies, such as the known moons of the giant planets, and their orbits.
Cloutier and his colleagues developed computer simulations based on the modern-day trajectories of Callisto and lapetus, the regular moons orbiting around Jupiter and Saturn respectively.
"Ultimately, we found that Jupiter is capable of ejecting the fifth giant planet while retaining a moon with the orbit of Callisto," said Cloutier.
"On the other hand, it would have been very difficult for Saturn to do so because Iapetus would have been excessively unsettled, resulting in an orbit that is difficult to reconcile with its current trajectory," Cloutier said.
