Melodie Kao et al. have something on LSR J1835+3259's magnetic-field.
This star is in Lyra at 18.55 lightyears away; probably better viewed from Vega than from here, whence we found it in 2003. There was some dispute about whether to class it as a brown dwarf but, eventually, we figured: star. Its auroras were noted July 2015 so we've long figured it had a magnetic field. Now we've looked for the radiation belt proper, which Kao's crew have found.
LSR J1835+3259's belt is scary: 10 million times brighter than Jupiter’s
. This, I think, should remove any atmosphere from a planet in this star's HZ.
It takes material to make a radiation-belt from a magnetic-field. Wikipedia suggests either some melted Io down there, or else the surface of this star itself.
As stars go, the fluid generating this field would be ionized hydrogen. Earth has iron; Ganymede induces its field from saltwater.
I have to wonder about the Proxima Centauri system, b and d (c being nonexistent). d is the inner one. I wonder if it is still spewing lava. If so, we can once more bet against d being habitable as it is lashed by d's ions. Same with TRAPPIST-1.
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