Well failed star is an erroneous term it just means any star that is not bright enough and hot enough that any world around it could sustain life (at least carbon-based as we know it to be).
Any world close enough to have liquid water would be so close as to be irradiated beyond anything we consider to be survivable and probably tidily locked to boot.
It’s still a star in the real sense of the term just quite dim and cool.
No, it means that it failed to become a star by initiating stellar fusion reactions. This isn’t some science fiction term. Red dwarfs are stars, and brown dwarfs are not.
Well failed star is an erroneous term it just means any star that is not bright enough and hot enough that any world around it could sustain life (at least carbon-based as we know it to be).
Any world close enough to have liquid water would be so close as to be irradiated beyond anything we consider to be survivable and probably tidily locked to boot.
It’s still a star in the real sense of the term just quite dim and cool.
No, it means that it failed to become a star by initiating stellar fusion reactions. This isn’t some science fiction term. Red dwarfs are stars, and brown dwarfs are not.