The sun fires off its biggest solar flare in more than 3 years

Interesting article. To place our Sun and solar flares into a larger, astronomical context. Recent reports of flares at Barnard's star show how very active and dangerous some stars are compared to our Sun. 'Assessing the habitability of planets around old red dwarfs', https://phys.org/news/2020-10-habitability-planets-red-dwarfs.html

“A new study using data from NASA's Chandra X-ray Observatory and Hubble Space Telescope gives new insight into an important question: how habitable are planets that orbit the most common type of stars in the Galaxy? The target of the new study, as reported in our press release, is Barnard's Star, which is one of the closest stars to Earth at a distance of just 6 light years. Barnard's Star is a red dwarf, a small star that slowly burns through its fuel supply and can last much longer than medium-sized stars like our Sun. It is about 10 billion years old, making it twice the age of the Sun…The research team's Chandra observations of Barnard's Star taken in June 2019 uncovered one X-ray flare (shown in the inset box) and their Hubble observations taken in March 2019 revealed two ultraviolet high-energy flares (shown in an additional graphic). Both observations were about seven hours long and both plots show X-ray or ultraviolet brightness extending down to zero. Based on the length of the flares and of the observations, the authors concluded that Barnard's Star unleashes potentially destructive flares about 25% of the time..."

We have a new report on the habitability of Proxima Centauri b and c now indicating that the host star stellar wind blows on it (b) some 10,000 stronger than Earth receives from our Sun. 'An Earth-like stellar wind for Proxima Centauri c', https://phys.org/news/2020-11-earth-like-stellar-proxima-centauri.html

"...The comparatively low surface temperature means that its habitable zone lies very close to the star and Proxima b, with its mass of about 1.2 Earth-masses, lies about twenty times closer to the star than the Earth does to the Sun, orbiting in only 11.2 days. Being as close as it is to its star, Proxima b (like all habitable-zone exoplanets around M-dwarf stars) is susceptible to stellar flares, winds, X-rays, and other kinds of activity that could disrupt its atmosphere and possibilities for life. These activities are linked to the strong magnetic fields in M-dwarfs, and they remain active in dwarf stars over much longer timescales than in higher-mass stars like the Sun, so that the cumulative exposures are commensurately greater. All these issues have been investigated in some detail for Proxima b; one conclusion, for example, is that it is probably subject to wind pressures ten thousand times larger than those exerted by the Sun on the Earth."

Astronomical context like Barnard's star flares or Proxima Centauri b stellar winds shows how stable our Sun is compared to other stars in the galaxy. That is good for life here too :)
 

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