Extreme stellar activity and winds, especially in M dwarf stars, play an important role in the development of a planet and its atmosphere. These kinds of activity are linked to a star’s magnetic activity, but unfortunately, models are still unable to predict how atmospheric initial conditions evolve under intense radiation environments. Nevertheless, progress has been made using simple models. In the case of Proxima Centauri b, scientists have found that it is probably subject to wind pressures ten thousand times larger than occur on the Earth. Might stellar wind effects also be disrupting any atmosphere on Barnard’s Star b? Harvard-Smithsonian Center For Astrophysics (CfA) astronomers Julian Alvarado-Gomez, Cecilia Garraffo, Jeremy Drake, and Sofia Moschou and their colleagues conclude otherwise. The scientists note that BSb is much farther away from its star than is Promixa Cen b, well outside of the domain of the star’s corona. Moreover, an analysis of Barnard Star’s rotation and other properties implies that it is much older, between about seven and ten billion years, and any magnetic field processes should be considerably smaller. The astronomers conclude that although today the planet Barnard’s Star b may have a relatively mild space climate (comparable, nevertheless, to bad space weather conditions for Earth), in its early years it probably did undergo significant disruption. Today, however, BSb might retain an atmosphere that could be studied. Reference: “Breezing through the Space Environment of Barnard’s Star b” by Julian D. Alvarado-Gomez, Cecilia Garraffo, Jeremy J. Drake, Benjamin P. Brown, Jeffrey S. Oishi, Sofia P. Moschou, and Ofer Cohen, 29 March 2019, ApJL.DOJ: 10.48550/arXiv.1901.00219
