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A physically realistic stellar wind model based on Alfven wave dissipation has been used to simulate the wind from Barnards Star and to estimate the conditions at the location of its recently discovered planetary companion. Such models require knowledge of the stellar surface magnetic field that is currently unknown for Barnards Star. We circumvent this by considering the observed field distributions of three different stars that constitute admissible magnetic proxies of this object. Under these considerations, Barnards Star b experiences less intense wind pressure than the much more close-in planet Proxima~b and the planets of the TRAPPIST-1 system. The milder wind conditions are more a result of its much greater orbital distance rather than in differences in the surface magnetic field strengths of the host stars. The dynamic pressure experienced by the planet is comparable to present-day Earth values, but it can undergo variations by factors of several during current sheet crossings in each orbit. The magnetospause standoff distance would be $sim$,$20 - 40$,% smaller than that of the Earth for an equivalent planetary magnetic field strength.
We have performed mid-infrared imaging of Barnards Star, one of the nearest stars to the Sun, using CanariCam on the 10.4 m Gran Telescopio Canarias. We aim to investigate an area within 1-10 arcsec separations, which for the 1.83 pc distance of the
The search for Earth-like planets around late-type stars using ultra-stable spectrographs requires a very precise characterization of the stellar activity and the magnetic cycle of the star, since these phenomena induce radial velocity (RV) signals t
The circumstellar environments of classical T Tauri stars are challenging to directly image because of their high star-to-disk contrast ratio. One method to overcome this is by using imaging polarimetry where scattered and consequently polarised star
The light curve of KIC 8462852, a.k.a Boyajians Star, undergoes deep dips the origin of which remains unclear. A faint star $approx$2arcsec to the east was discovered in Keck/NIRC2 imaging in Boyajian et al. (2016), but its status as a binary, and po
We study the interaction of three solar wind structures, two stream interaction regions and one interplanetary coronal mass ejection, with Mars plasma environment during 20-27 November 2007. This period corresponds to the solar minimum between the so