BULLETIN

Betelgeuse’s dimming explained

The star’s exceptional dimness earlier this year was observed during a Hubble study

A stellar ‘sneeze’ was responsible for Betelgeuse’s unprecedented period of dimming at the beginning of the year, according to a recent update from astronomers who had been monitoring the star. They revealed that it had experienced an outburst of a huge cloud of material just before it began to dim, hiding a quarter of the star from view.

Betelgeuse is a red giant and a favourite for astronomers, partly due to its prominence in the constellation of Orion and partly because it’s expected to go supernova at any time in the next 100,000 years. Its brightness is known to vary slightly, but in October 2019 it dimmed dramatically and by mid-February it was around three times fainter