  The Hunga Tonga-Hunga Ha'apai volcano erupted on 15 January 2022 with an
energy equivalent to around 61 megatons of TNT. The explosion was bigger than
any other volcanic eruption so far in the 21st century. Huge quantities of
particles, including dust and water vapour, were released into the atmosphere.
We present the results of a preliminary study of the effects of the explosion
on observations taken at Paranal Observatory using a range of instruments.
These effects were not immediately transitory in nature, and a year later
stunning sunsets are still being seen at Paranal.
