The Globe and Mail reports that a team of four astronomers have proven, via computer modeling, that gas giants can form in hundreds of years rather than millions of years, as was previously thought. Their findings were published in today’s edition of Science Magazine. Until now, the only theory of planetary formation that was thought to be effective was that of rocks colliding together–which would take millions of years. The computer model now reveals that the initial protoplanetary nebula (a disc of gas) begins to fragment after just a few orbits around its star. As the disc fragments, clusters of matter begin to coalesce, which draw in the gases that form vapour shrouds around giant gas planets.
One of the scientists, Dr. Thomas Quinn, astronomy professor at Seattle’s University of Washington, said that the much higher number of planets that might exist as a result of their findings would be gas giants, not planets like Earth. “On the other hand, there could be Earth-like bodies orbiting these giant planets, much like Europa orbits Jupiter.”
This theory has major implications in understanding the hundred or so “hot Jupiters” found so far around other stars in the past few years. Most have orbital periods of only a few days (instead of the months or years found in our Solar System) and orbit at a distance from their stars that is less than Mercury is from our Sun. Trying to see why some solar systems end up like THAT as a stable configuration and others like OURS has been a major mystery. Perhaps this work will lead to the conclusion that hot Jupiters are newly-formed and therefore perhaps transient phenomena?