2/ To be clear, the star has almost exactly the same mass as the Sun, but it’s far younger, about 17 million years old. The planets are glowing with the leftover heat of their formation.

We only have direct images of two other planetary *systems*…
3/ PDS 70, where we still see the ring of material the star and planets are forming from…

https://www.syfy.com/syfywire/alma-reveals-a-dusty-ring-around-a-young-exoplanet-that-may-be-forming-moons
4/ … and HR 8799, which has *4* planets orbiting quickly enough that an animation shows their motion around the star! This one just floors me. Incredible.
6/ Back to the topic, the 2-planet system (called TYC 8998-760-1) is about 300 light years away, and the planets orbit really far out, 160 ad 320 times the Earth-Sun distance. That’s a long walk. It’s not clear if planets can even form that far out in a system like this.
7/ If they did form there we need to figure out how massive planets (6 and 14 times Jupiter’s mass) could gather that much material out that far from the star.

If they didn’t, how did they get out there? Likely an encounter with a third, even more massive planet.
8/ That could slingshot them away from the star. But their motion would be hard to measure from Earth, and that’ll take years to see. So it’s a bit of mystery at the moment.

But dang. This is all so cool.
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