Takanori Sasaki (born 1979) is a Japanese planetary scientist who uses theory and numerical simulations to investigate the origins and evolution of planets and satellites. Born in Karatsu, Saga Prefecture, he graduated in Earth and planetary physics from the University of Tokyo in 2003 and completed its doctoral programme in Earth and planetary science in 2008, earning a doctorate in science. After serving as a JSPS postdoctoral fellow, specially appointed assistant professor, and specially appointed associate professor at the Tokyo Institute of Technology, he joined Kyoto University’s Department of Astronomy as an assistant professor in 2014. His research examines how planets grow within the disks of gas and dust surrounding young stars, how collisions shape them, and how their atmospheres evolve. These questions inform his investigations of how Earth acquired water and conditions compatible with life. In collaborative work on Uranus’s satellites, he investigated the spreading and cooling of a disk produced by a giant impact, the condensation of water vapour into ice, and the subsequent growth of satellites. His 2017 Japanese-language book “Wakusei no Hanashi: Wakusei Keiseiron e no Shotai” begins with the present Solar System and explains the formation of its planets and moons alongside the diverse planetary systems discovered around other stars. It then considers the conditions under which a life-bearing planet like Earth could form. His 2021 book “Chikyu Igai ni Seimei o Yadosu Tentai wa Aru no Daroka?” develops this interest for general readers. Moving from the history of astronomy to water on Mars, Europa’s internal ocean, Titan, Enceladus, and methods of finding exoplanets, it used planetary missions and space-telescope observations to explain where scientists look for environments that might support life.
