Free Astronomy Magazine January-February 2025

10 JANUARY-FEBRUARY 2025 ASTRO PUBLISHING suggesting a varied composition and providing new insights into the for- mation and evolution of the solar system. Centaurs are former trans- Neptunian objects that have been moved inside Neptune’s orbit by sub- tle gravitational influences of the planets in the last few million years, and may eventually become short- period comets. They are “hybrid” in the sense that they are in a transi- tional stage of their orbital evolu- tion: Many share characteristics with both trans-Neptunian objects (from the cold Kuiper Belt reservoir), and short-period comets, which are ob- jects highly altered by repeated close passages around the Sun. Unusual jets of volatile gas from icy Centaur 29P I nspired by the half-human, half- horse creatures that are part of Ancient Greek mythology, the field of astronomy has its own kind of centaurs: distant objects orbit- ing the Sun between Jupiter and Neptune. NASA’s James Webb Space Telescope has mapped the gases spewing from one of these objects, by NASA/ESA/CSA Abigail Major Christine Pulliam