Gliese 229 at 5.7612 parsecs out was the first brown dwarf system discovered, in 1995. At minimum 70 jovian mass, the orbiter annoyed researchers as a Dog Not Barking. This close it should have been big enough against a star faint enough, to see. When the orbiter was seen, almost face-on to our eyes: it was seen in 2008 as 950 K, seen as too dim - a mere T on the scale.
The mystery is solved: it's two. And their age can be measured therefore certainly that of their main star A. It helps I suppose that they can now bootstrap what Luhman 16 has taught us about binary "brownz" (per Razib).
That main star has planets, also; planet Ac - the second found - floats in the habitable zone. As a Msini=7 "super earth" around an Archaean star, it is not tidally-locked and has assuredly kept its atmo. Which is not to say that planets this large be life-candidates; it's like to be a Sudarsky II with some supercritical fluid below its clouds. Hence why I didn't take it seriously when sketching potential colonies.
Both A planets are eccentric. As for the BC brownz, they're 70 joves of mass periapse 29 × (1 - 0.853) = 4.263 AU. So... yeah, they're going to perturb orbits. One might apply von Zeipel to their dynamics. That's good mainly for telling us that the planets' inclinations are hard to constrain and subject to change. Although, they'll probably never transit their star to our sight.
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