Very cool discovery. But just to temper any overly excited reactions...
Whether the atmosphere could support life remains unknown.
Also LHS 1140 b is tidally locked to its red dwarf Star, which means one side of it is constantly facing the star and the other side is always saving away from the star. So the ~~fat~~ far side will be very, very cold. While the doesn't rule out the possibilities of life or a breathable atmosphere, it does complicate all that.
