Last night the Drudge Report, no less, pointed to CNN (no less) on YZ Ceti. CNN's article was blisteringly stupid, not recognising that the planet is hot; so I waited for a nonmoronic take, which Kiona Smith has provided today.
This system is 12 light years away from us, 1.6 ly from the famous (and older) Tau Ceti. Tau Ceti f is considered habitable as a cold super-Earth, less cold if greenhoused. If it exists.
But we are here for YZ, closer our age. These planets so-far uncovered are, as noted, too hot. What's interesting to the researchers is that the inner planet has a magnetic field, raising aurorae upon the star. Yes they are that close to the star. But they could be closer! So what's causing the field? Smith thought that the star's flares might be keeping the planet molten. I'm less sure of that, myself.
Inner planet is 2,444,430 km semimajor. That's outside Callisto 1,882,700 km; more like TRAPPIST-1c 2,363,650. And YZ's planets have more mass.
I find interesting, their orbits: 2.02, 3.06, 4.65. What is this - 3:2 resonance, and 3:2? Or if you like 9:6:4. Compare TRAPPIST. Pretty sure the Hill Spheres and resonances could constrain their masses and inclinations as with TRAPPIST. It is not a perfect resonance: tides on the star have, I think, pulled b and c both, pushing d away like GJ 1002 c.
TRAPPIST-1's inner planets are bigger and the innermost is an airless supermercury. Inasmuch as T1 b runs closer to its star than does YZC b: I get the impression T1 b does not exude such a field.
It may be that the YZC resonances are squeezing that innermost planet's core. Is this a constraint upon YAZ b's and T1 b's cores?
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