The distant imagery appears in a recent paper by Anna McLeod and colleagues (Nature https://doi.org/10.1038/s41586-023-06790-2; 2023) and is a product of two instruments: the Multi-Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope, and the band 7 receivers of ALMA. The MUSE optical image on the left provides context. Shown is the parent cloud, LHA 120-N 180B, where a resilient proplyd (highlighted by the box) can be seen just inside the rim of the H ii-region-blown bubble. The spectroscopic capabilities of MUSE mean that any motions towards and away from us, for instance arising from gas being ejected from the young star in outflows, can be decomposed into blueshifts and redshifts (centre image). Stellar outflows are a signpost for ongoing accretion, but to be sure of this, evidence for a disk is required. The expansive baselines of the ALMA interferometer provided the high angular resolution (~50 mas) needed to probe the innermost circumstellar regions, and was sufficient to reveal indications of Keplerian rotation (seen in the centre of the right-hand image). In the panel, the red and blue colours set against the white-ish central regions illustrate rotation in an anti-clockwise direction, as seen from Earth. The overall picture is of a spinning ~6,000 au radius toroid of gas feeding material from larger scales onto an accretion disk around a recently born ~10–20 M⊙ star.
This scenario is very similar to that seen for high-mass young stellar objects (YSOs) in the Milky Way in recent years, which also echo the morphology and dynamics of low-mass YSOs. The advantage offered by targets in the LMC is that they are obscured by dust to a much lower degree than in the Galaxy. In the pictured instance the central star of the system, HH 1177, is even exposed. Aside from this difference, other aspects of the HH 1177 system are comparable to Galactic massive YSOs: disk mass, surface density and size. An open question remains around the stability of the disk, which, given the size, is expected to be unstable at the lower metallicity of the LMC, but a calculation of the Toomre Q parameter using the present (and somewhat uncertain) disk parameters results in Q > 1, indicating stability. Detailed modelling of Galactic and extragalactic accretion disks around massive stars will be necessary to quantitatively understand these systems further.
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