First ever live observation of the rotation of a planetary nursery
Space
The rotation of a protoplanetary disc (a disc where planets are being formed) has been observed directly for the very first time by mapping the emissions from the dust grains within it. The disc in question surrounds the young star AB Aurigae1. Although it appears to generally rotate in accordance with the laws of physics, certain regions close to the star show an unexpected departure from this behaviour. A body of evidence suggests that this anomaly is caused by the presence of giant planets in the process of formation. The study, led by scientists from the CNRS and the University of Bordeaux2 is published in the journal Astronomy & Astrophysics on June 1, 2026. It sheds fresh light on the mechanisms of planetary formation and the complex dynamics of protoplanetary discs.
Thanks to the unique near-infrared capabilities of the SPHERE3 instrument and its exceptional spatial resolution, the team was able to accurately track the disc's structures and their evolution during three sets of observations, collected over a 4-year period. The scientists identified a bright structure, characteristic of accretion zones where gas and dust accumulate and fall onto an object in the process of formation. This phenomenon is closely linked to the formation of gas giant planets. Images of the AB Aurigae disc also reveal the rapid rotation of faint shadows cast onto its surface by invisible structures, which could possibly be protoplanets (planets in the process of formation) or opaque clumps of dust orbiting close to the star.
These findings, which are more complex than those predicted by theoretical models, underline the importance of continuing research aimed at directly detecting the properties of the protoplanets or clumps associated with the structures observed in the AB Aurigae disc.
Notes
- AB Aurigae is a star in the constellation Auriga.
- Working at the Laboratoire d'instrumentation et de recherche en astrophysique (CNRS/Observatoire de Paris – PSL/Sorbonne Université/Université Paris Cité) and at the Laboratoire d'astrophysique de Bordeaux (CNRS/université de Bordeaux). Scientists at the Laboratoire Astrophysique, instrumentation, modélisation (CEA/CNRS/Université Paris Cité), Institut de planétologie et d'astrophysique de Grenoble (CNRS/Université Grenoble Alpes), the Laboratoire Joseph-Louis Lagrange (CNRS/Observatoire de la Côte d’Azur/Université Côte d’Azur), and the Centre de recherche astrophysique de Lyon (CNRS/ENS de Lyon/Lyon 1 Université Claude Bernard) also took part in this work.
- SPHERE, developed by a European consortium, is an instrument on ESO's Very Large Telescope in Chile, on which it has been installed since 2014.
Bibliography
Destructuring the disk of AB Aurigae: dynamics and accretion
Anthony Boccaletti, Emmanuel Di Folco, Anne Dutrey, Tang Ya-Wen, Stephane Guillotea, Thomas Collin-Dufresne, Anne-Marie Lagrange, Eric Pantin, Jeffrey S. Bary, Nuria Huelamo, Jozsef Varga, Julien Milli, Vincent Pietu, William Danchi, Bin Ren, Clement Baruteau, Mickael Bonnefoy, Tracy Beck, Maud Langlois, Sylvestre Lacour, Bruno Lopez, Alexis Matter, Julien Woillez, Florentin Millour, Matthis Houllé, Philippe Berio, Astronomy & Astrophysics, 1 June 2026.
