Max Pettini is an observational astronomer who studies interstellar matter in a variety of cosmic environments. His early research provided the first evidence for — and verified an earlier prediction of — the presence of a halo of hot ionised gas surrounding our galaxy.

His studies have focused mainly on high redshift galaxies and the intergalactic medium: he is particularly interested in studying the chemical composition of gas in these distant systems with a view to unravelling their origin and evolution. To pursue this research, he has been involved in the development and exploitation of high-resolution spectrographs on some of the world's major optical and infrared telescopes.

Max has received a number of accolades in recognition of his work, including the Herschel Medal of the Royal Astronomical Society in 2008.