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Image credit: Indiana University
Oblate Jupiter
Considering all planets as being spheres? It might not be that simple.
Using a supercomputer, a team of astrophysicists have simulated how gas giants like Jupiter grew in the first place — and came to the conclusion that they likely had a flattened shape, kind of like an M&M, during its early days.
“We have been studying planet formation from a long period of time but we never thought to check out the shape of planets as they form in the simulations,” said University of Central Lancashire astrophysicist Dimitris Stamatellos, coauthor of a new paper to be published in the journal Astronomy & Astrophysics Letters, in a statement. “We had always assumed that they were spherical in shape.”
“We were very shocked when we get to know that they turned out to be oblate spheroids, pretty similar to smarties!” he added, referring to the popular chocolate confection that’s only available outside the US.
Flattened Spheroids
Despite the over 5,500 planets discovered in our Milky Way alone, scientists are still not properly sure how they’re formed.
According to current theories, massive clouds of gas and dust circling stars start clumping together due to gravitational forces to form planets, comets, asteroids, and moons.
At least, that’s the case for small, rocky planets like Earth and Mars.
For gas giants the size of Jupiter and larger, scientists believe they’re made by the “breaking up of large rotating protostellar discs around young stars in short timescales,” as lead author and recently graduated PhD student at the University of Central Lancashire Adam Fenton explained in the statement, a theory known as “disc-instability.”
“This theory is appealing due to the fact that large planets can form very quickly at large distances from their host star” he added by describing some exoplanets observations.
According to the team’s computer simulations, gas giant planets likely at first made a flattened shape — or “oblate spheroids” — due to the centrifugal forces included, and by having material mostly fall onto their poles rather than their equators.
The scientists argue we should take these detections it was into consideration during future observations of young planets. For one, the observed shape of an oblong object when it was viewed through a telescope could change depending on the viewing angle.
And that’s more important than ever, given the progress we’ve made when it comes to watching planets being born from many light-years away.
