Last month Stephen R. Kane did a dynamic on HD 141399. He chose this because it is a K-class "goldilocks" with a 0.644 sini Mj giant out at (dynamically-generated) 4.5 AU. Which would be its Jupiter!
This system's young: that "K0V" weighs in at 1.091 M⊙ (I'm unsure how they figured that, absent Kepler) and shines bright (per GDR2) 1.637 L⊙. Habitable-zone is presently 1.233–2.190 AU as a result (conservatively). I expect its HR path to subside to G like our own Sun as it ages; that HZ should shrink down to 1 AU as that result. If the system does own an Earthlike, that Earthlike will be Hadean. Maybe it can get some ice delivered to it . . .
...except that this HD 141399 outer planet is "e". The system owns three other superSaturns and superJovians. These three are all inbound; the "c" is at 0.693 AU (like Venus) and the "d" is 2.114 AU (like Vesta). We don't have such monsters bookending our green Earth and we never did. Eccentricities roam around 0.04-0.053, also; not quite as oval as Mars' 17kBC minimum 0.079, but still worse than Earth's today. And the inclinations came to Kane absurdly ill-constrained 10-85° so we don't even know their masses, not really. Both c and d are certainly over 1.3 Mj.
There might be a problem allowing for Earthlikes in-between. That's right: it's MMR time, if we can squeeze something into a Laplacian or maybe a Trojan.
Kane calculates that the innermost (and smallest) superSaturn "b" librates its orbit with giant c's, around a 2:1 resonance. The whole system is stable - so if these planets ever did a Grand Tack, that tacking is done. But Kane is skeptical about stability for whatever other planetoids are within 4.5 AU. I doubt that "b" or "c" are attracting much in the way of Trojans, either.
As I read Kane, we can allow for an asteroid-belt of S-types in the 1.2-1.7 AU range, currently on the hot side, but not forever. Also "d" can attract stable Trojans in SdL4 and L5 (nobody cares about "e" here). Giant d likely has tides, on which Kane didn't speculate. But out at 2.19 AU, which by simple geometry means the haloes centre 2.19 AU from the planet as well: these tides are most unlikely to exceed the d Hill-sphere. Some of these "asteroids" could well be larger than our own Ceres (especially this early in the system's life).
As to d's Hill... one possibility, also unspeculated by Kane, is that this could capture sufficient mass in ice and silica for a moon. I might go up to the size of Mars. Mildly irradiated, if this aggregated at a Europalike distance; but if there's a core, like Ganymede has a core, that might protect it.
LOL FRONTDATE 11/5 - yeah, I'd some stuff lined up over the last weekend. So y'all got to enjoy this one a little earlier than my usual after-work hours
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