'Sub-Saturns' May Force Scientists to Revise Idea of How Planets Form

Space.com ^ | January 12, 2019 08:43am ET | Meghan Bartels,

[BenLurkin]

Astronomers know our solar system better than any other, but they're still learning new ways in which it doesn't seem to be particularly normal.

Right now, the leading theory of planetary formation, called the "core accretion model," is tailored to explain what we see in our solar system — the only one we knew much of anything about when the model was developed. But the more planets we identify in other solar systems, the more we find they don't match the patterns of mass and orbital distances found here on our own.

Take, for example, the staggering size gap between Neptune and Saturn. Neptune is about 17 times the mass of Earth, whereas Saturn is far bigger at 95 times Earth's mass, according to NASA. In between, nothing. The core accretion model explains that gap with a mechanism called "runaway gas accretion."

…

There's just one problem: Astronomers have realized that other solar systems do host plenty of planets with sizes between these extremes, nicknamed sub-Saturns. A paper published in December in The Astrophysical Journal Letters and presented at the meeting compared 30 different planets identified by a specific technique with what scientists would expect to see based on the core accretion model. In that survey, they found the model doesn't match very well with reality.

That gives our solar system a new weird quirk — its missing sub-Saturns.

And the lack of such planets overall is because they're really hard to detect. There's only one technique powerful enough to identify planets that orbit beyond what astronomers call the "snow line," where loose material in an early solar system is far enough from its sun that light materials like water can freeze — the sort of neighborhood you need to search to find sub-Saturns.

[CIB-173RDABN]

Wouldn’t be any point in doing science if everything was known. This would please Luddites who enjoy the civilizational benefits derived from the scientific method while denouncing it from the cheap seats.

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I was being sarcastic ( /s) with a subtle (perhaps too subtle) reference to man made global warming.

When it comes to “man made global warming” is it is settled and no arguments against this is acceptable (sort of like when the church believe earth was the center of the universe.