The existence of a fifth giant gas planet at the time of the solar system’s formation — in addition to Jupiter, Saturn, Uranus and Neptune that we know of today — was first proposed in 2011. Now astrophysicists at the University of Toronto have found that a close encounter with Jupiter about four billion years ago may have resulted in the fifth giant planet’s ejection from the solar system altogether.
Earth came early to the party in the evolving universe. According to a new theoretical study, when our solar system was born 4.6 billion years ago only eight percent of the potentially habitable planets that will ever form in the universe existed. And, the party won’t be over when the Sun burns out in another 6 billion years. The bulk of those planets — 92 percent — have yet to be born.
Researchers at Southwest Research Institute (SwRI) and Queen’s University in Canada have unravelled the mystery of how Jupiter and Saturn likely formed using computer simulations. The discovery, which changes our view of how all planets might have formed, also suggests that the gas giants in the solar system probably formed before the terrestrial planets.
An international team of scientists has solved an age-old scientific riddle by discovering that planetary rings, such as those orbiting Saturn, have a universally similar particle distribution. The study also suggests that Saturn’s rings are essentially in a steady state that does not depend on their history.
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