Observation of an accreting planetary-mass companion with signs of disc–disc interaction in Orion

Abstract

Young (≲10 Myr) planetary-mass companions (PMCs) provide valuable insights into the formation and early evolution of planetary systems. To date, only a dozen such objects have been identified through direct imaging. Using JWST/NIRCam observations towards the Orion Nebula, obtained as part of the PDRs4All Early Release Science program, we have identified a faint point source near the M-type star V2376 Ori, a member of Orion D, around 80 pc in the foreground of the Trapezium cluster of Orion and with an age of approximately 7 ± 3 Myr. Follow-up spectroscopic observations with the MUSE instrument on the VLT confirm that the source, V2376 Ori b, is indeed a young PMC. We fit the SED of V2376 Ori b and infer a mass of ∼20 MJup with evolutionary tracks. The MUSE spectrum reveals several accretion tracers. Based on the Hα line intensity, we estimate an accretion rate of ∼10−6.6 ± 0.2 MJup yr−1, which is comparable to that of young PMCs such as PDS 70b. In addition, the MUSE data cube reveals extended emission in the [O II] doublet at 7320 and 7330 Å, which is interpreted as evidence of a dynamical interaction between the two sources that potentially involves mass transfer between their individual accretion discs. These results demonstrate that JWST/NIRCam imaging surveys of young stellar associations can uncover new PMCs, which can then be confirmed and characterized through ground-based spectroscopic follow-up.