Astronomers spot huge solar flare from star Proxima Centauri
Astronomers at the Carnegie Institution for Science have detected a massive solar flare emanating from dwarf star Proxima Centauri. This discovery strengthens the hypothesis that the nearby exoplanet Proxima b is probably unsuitable for life.
The peak brightness of the solar flare, observed on March 24, 2017, was found to be ten times brighter than the largest solar flares from the Sun, observed at similar wavelengths. The solar flare caused the nearby exoplanet Proxima b to become about 1,000 times brighter than normal for ten seconds. Prior to the great solar flare, there was another smaller flare.
According to researcher Meredith MacGregor, it is likely that Proxima b was bombarded with high-energy radiation during the massive solar flare. The researcher says it was already known that Proxima Centauri was more likely to cause smaller flares, but she says any previous similar massive flares may have blown and evaporated any of Proxima b’s atmosphere and ocean.
The flare occurred in March last year and was discovered by reanalyzing observation data from the Atacama large millimetre/submillimetre array, a large radio telescope in Chile consisting of 66 antennas. According to the researchers, solar flares from stars other than the Sun have not yet been properly studied at the wavelengths at which they were detected by the Alma telescope. Solar flares also occur near the sun and are explosions on the surface of a star that send an enormous amount of radiation into space.
Exoplanet Proxima b was discovered in 2016 and is located at a distance of ‘only’ 4.24 light-years from Earth. It has already been assumed not to be a good candidate for possible extraterrestrial life, because the nearby red dwarf star Proxima Centauri is very active. Compared to Earth, the planet is about twenty times closer to its star.
According to MacGregor, the new research also shows that there are no multiple disks of dust orbiting Proxima Centauri, as claimed in a previous paper. According to the researchers of this paper, the presence of the dust could mean that there must be more planets in the system of Proxima Centauri. However, there are no indications for the presence of more exoplanets, according to MacGregor.
The research is published in the scientific journal The Astrophysical Journal Letters under the title Detection of a Millimeter Flare From Proxima Centauri.