Between September last year and this February , red supergiant Betelgeuse experienced anunprecedented dimming periodthat led the supergiant to throw away out of the Top 20 shiny ace in the night sky .
Betelgeuse ’s bodily function lead to surmise it was hint at itsimpending supernova . However , as a variable principal , Betelgeuse experiences changes in its brightness every 420 day , and this current dimming fits with this just being an extra - inviolable round . Why it reached such anexceptionally low luminosity , dropping to around 40 percent of its usual luminance , is still odd . Now researchers have a new possibility , blaming it on a release of rubble from its proscribed layers ; basically , a sneezing .
A fresh paper , accepted in theAstrophysical Journal Letters , points out that the temperature of the superstar has changed marginally during this geological period and it is , in fact , warmer than it should be if its dimming was do by the ace ’s cooling surface . Instead , they conceive the star got rid of some of its textile from its outer layers , which is blocking the light .
“ We see this all the time in cherry-red supergiants , and it ’s a normal part of their life cycle , ” lead author Professor Emily Levesque from the University of Washington say in astatement . “ crimson supergiant will once in a while shed cloth from their surfaces , which will condense around the star as dust . As it cool down and dissipates , the dust grain will absorb some of the light channelise toward us and block our eyeshot . ”
Levesque and her co - source Philip Massey were part of the squad who had previously gauge the temperature of the surface of the star in 2004 . They take observations on February 14 2020 to judge how much Betelgeuse had cool down down . It turn out , not very much at all . The ordinary aerofoil temperature of the asterisk is 3,325 ° C ( 6,017 ° degree Fahrenheit ) . That ’s only between 50 - 100 ° C ( 90 - 180 ° F ) cooler than the previously reckon temperature .
“ A compare with our 2004 spectrum showed immediately that the temperature had n’t change significantly , ” said Massey . “ We knew the answer had to be rubble . ”
cloud of dust have been note around other stars as well and the squad is confident that fresh observations of Betelgeuse will let on them here as well . However , this is only one reason to continue looking at this virtuoso . Betelgeuse is the nearest red supergiant to Earth and it is a double-dyed laboratory to work out how these celestial physical structure evolve .
“ reddish supergiants are very dynamic stars , ” said Levesque . “ The more we can see about their normal behavior — temperature fluctuations , dust , convection cells — the well we can understand them and recognize when something truly unequaled , like a supernova , might happen . ”
