Feb. 24, 2020: Call off the supernova watch. Betelgeuse is brightening again. Researchers from Villanova University, who have been leading the study of Betelgeuse’s unprecedented decline, have confirmed in a new Astronomical Telegram that the star has reversed itself. The turnaround was actually predicted, and suggests the recent dimming was an unusually deep excursion of the star’s natural 430-day periodicity.
Here are the latest data from the American Association of Variable Star Observers (AAVSO):
According to the light curve, Betelgeuse hit bottom during the week of Feb. 7th – 13th with a V magnitude slightly greater than +1.6. “Based on these and additional observations, Betelgeuse has definitely stopped dimming and has started to slowly brighten,” says Ed Guinan of Villanova University. “Thus, this ‘fainting’ episode is over.”
The monitoring should continue, however. Sensational images captured last month by the ESO’s Very Large Telescope in Chile revealed that one half of Betelgeuse was dimming more than the other. No one knows why. Additional imaging during Betelgeuse’s recovery might unravel the mystery.