Overview
- An international team used nearly eight years of ALMA positional monitoring combined with VLA, JWST and VLT data to reconstruct the full three-dimensional orbit of the young massive protobinary IRAS 07299−1651.
- The orbital fits favor highly eccentric solutions that lie close to a parabolic trajectory rather than a stable, circular orbit expected from shared-disk formation.
- Each protostar hosts a compact, rotating circumstellar disk and a jet, and those disks and jets are strongly tilted relative to one another and to the orbital plane.
- The authors interpret these features as the result of a recent near-parabolic ‘core-merger’ or close gravitational encounter with a closest approach on the order of decades ago, but they note it remains an actively testable hypothesis and the pair’s long-term fate is uncertain.
- If confirmed in other systems, this encounter pathway would offer an alternative route to the high binary fraction among massive stars and the team says similar long-term, multi-observatory studies are needed to measure how common it is.