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Extremely cool that they were able to predict when to look for additional, undetected planets and then actually find them.

Also, despite being a huge nerd for astronomical scales, I'm still easily shocked at them. I didn't expect a system to exist with six (!) larger-than-Earth planets in stable sub-Mercury orbits around a sun-like star. My mind tells me there's not enough space, that they should be ripped apart by each other or the star. Yet it's actually one of the most peaceful, gentle systems we've ever found.

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Shameless plug, but if you're into astronomical scales you might like this little visualization tool I've built recently!

https://github.com/pedrosbmartins/downtoearth

I found this to be the best visualization for me: https://omgspace.net

Man there's some amazing graphics on there. Just 5 minutes into exploring it, and everything is laid out so beautifully.

This is an awesome project, really great work. Also, how dare you omit Pluto!

Thank you!

And you can change visualizations in the dropdown, there is a special one for Pluto's eccentric orbit :)

Jupiter has four stable resonant satellites on the order of 1% of Earth's mass within an orbital radius of 1% of Earth's orbit. It's plausible by that example.

Not an expert, but the wikipedia article on orbital resonance[0] mentions Laplace's discovery of a 3 body resonance, Io–Europa–Ganymede. They are indeed OOM 1% of Earth's mass (Ganymede being 2.5% for example[1]).

0 - https://en.wikipedia.org/wiki/Orbital_resonance

1 - https://en.wikipedia.org/wiki/Ganymede_(moon)

I think the proximity is what caused the orbit resonances.

So your intuition that they should affect each other is correct, but the end result less catastrophic.

Of course, we don't know how many sibling planets crashed into their sun earlier...

> Of course, we don't know how many sibling planets crashed into their sun earlier...

My understanding is that it would be 0. A planet can't fall into its sun without being disturbed, because the planets and their sun all coalesce from the same rotating disc of material. If any planet had been disturbed enough to slow down and crash into the sun, it's hard to imagine that happening without the slightest disturbance to the 6 extant planets.

Could have been 7 or 9 wonky planets, then some fell into their sun and maybe one flew off or was torn apart then these remaining six wiggled around a bit from all that into resonance.

Space has, like, infinite possibilities.

Could be, but I don't think it's likely, which is why the article states that these planets have probably all been in their orbits since formation.

Main belt asteroids and comets are perturbed out of their orbits all the time. Why would planets be meaningfully different?

Because there's evidence that they weren't.

After the initial disturbance, the remaining planets would find a new equilibrium, which might be the current resonance situation.

> Yet it's actually one of the most peaceful, gentle systems we've ever found

You shouldn't assume that. With so much synchronicity I have to wonder if it creates any forces that would result in things like wildly high tides if a planet had any water on it, or increased quakes or some other phenomena caused by the alignments. It could be far from peaceful.

It's not an assumption - I meant gentle on a solar-system scale. You're right that the surface of the planets could be chaotic, but it sounded like they had massive atmospheres and potentially small rocky cores.

I mean, "peaceful" and "gentle" are kind of an anthropomorphism of sorts. I'm not even sure what "gentle on a solar-system scale" is supposed to mean.

It means undisturbed, as explained in the article.

I can assure you that plenty of things in this system are being disturbed. This is science sensationalism.

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