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According to Wikipedia, "For the first time, we can conclusively see the tell-tale signs of a circumplanetary disk, which helps to support many of the current theories of planet formation."

I'm confused though... doesn't our own Saturn have a circumplanetary disk?

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Do not read Wikipedia.

What is new here is the clear observation of a circumplanetary disk around an exoplanet. Such disks are where moons are formed, so this is the first observation of a moon-forming process outside of our solar system.

> so this is the first observation of a moon-forming process outside of our solar system

Is that really true? We've never seen moons forming elsewhere in the universe?

Correct. The ability to infer this from observational data was only possible with the technique pioneered in this paper.

Remember that we cannot even see exo-planets visually (with one or two very nearby exceptions).

According to Wikipedia, there are not even any confirmed exomoons yet. So it's interesting that a disk was observed first, although given size/brightness that's probably not a surprising result.

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