The dimming of Betelgeuse

In January-February 2020, our red supergiant neighbor Betelgeuse experienced an exceptionally deep photometric minimum at visible wavelengths. As it emerges from behind the Sun after the boreal summer, the apparent brightness of Betelgeuse is still at a low level. Betelgeuse is surrounded by a molecular and dusty envelope, that has been detected in the thermal infrared domain, in particular using VLT/VISIR and VLTI/MIDI. More generally, the close environment of Betelgeuse has been monitored from the ultraviolet to radio wavelengths using a variety of facilities, including adaptive optics and long-baseline interferometry. I will present an (incomplete) overview of the existing observations of the environment of Betelgeuse, with an emphasis on the thermal infrared domain, and how they could shed light on the recent dimming event