Dust composition beyond the equatorial ring of SN 1987A

Determine the composition of the dust located outside the equatorial ring of SN 1987A and establish whether the silicate–amorphous carbon and astrodust grain models that describe the equatorial ring’s optically thin mid-infrared emission are applicable to that external region.

Background

Using JWST/MIRI imaging, the paper constructs temperature and mass maps of dust in SN 1987A’s equatorial ring (ER), fitting optically thin models with silicate+amorphous carbon and with the astrodust mixture. These models provide reasonable temperatures and masses within the ER and are used to interpret the mid-infrared emission there.

However, the authors explicitly state that outside the ER the dust composition is not known, making it doubtful that the same models apply beyond the ER. This identifies an unresolved question about the nature of the dust populating regions adjacent to the ER and whether standard mid-infrared dust models remain valid in that environment.