  The very recent discovery of planets orbiting very low mass stars sheds light
on these exotic objects. Planetary systems around low-mass stars and brown
dwarfs are very different from our solar system: the planets are expected to be
much closer than Mercury, in a layout that could resemble the system of Jupiter
and its moons. The recent discoveries point in that direction with, for
example, the system of Kepler-42 and especially the system of TRAPPIST-1 which
has seven planets in a configuration very close to the moons of Jupiter.
Low-mass stars and brown dwarfs are thought to be very common in our
neighborhood and are thought to host many planetary systems. The planets
orbiting in the habitable zone of brown dwarfs (and very low-mass stars)
represent one of the next challenges of the following decades: they are the
only planets of the habitable zone whose atmosphere we will be able to probe
(e.g. with the JWST).
