At Fox News, University of Toronto physicists have drawn notice for speculating that our solar system once had an extra planet, a gaseous body that - it seems - was ejected from our solar system by either Jupiter or Saturn. A planetary ejection occurs when a planet, or other body, accelerates so fast, it breaks free of the gravitational pull of the star that it’s orbiting - typically, after having a close encounter with another large body. The U of T teams arrived at their conclusions by studying the orbits of nearby planets and their moons; in this case, the evidence points towards Jupiter as the prime suspect. The results were published in The Astrophysics Journal.
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