2025/09/17 by M W Healy-Kalesh, Manami Sasaki, Healy-Kalesh, Michael W. +15
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences
paper · pdf · doi:10.48550/arxiv.2509.14368
openalex publication_date 2025/09/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A nova super-remnant (NSR) is a greatly-extended structure grown by repeated nova eruptions sweeping the surrounding material away from a nova into a dense outer shell and are predicted to form around all novae. To date, four NSRs are known, with three located in the Galaxy and one residing in M31. Here we present the discovery of the first NSR in the Large Magellanic Cloud and only the second extragalactic nova shell to be identified, hosted by the recurrent nova LMCN 1971-08a. The structure is coincident with the nova, has a circular morphology and is visible in narrowband Hα and [S II] filters but very faint in [O III], as expected. HI data also potentially reveal the existence of a coincident structure. Further, with a diameter of ∼200 pc, this NSR is the largest example yet found, with models indicating an ∼4130 M\odot shell expanding at ∼20 km s-1 into the surrounding medium and an age of ∼2.4 Myr. The existence of the NSR also suggests that LMCN 1971-08a may have a much shorter recurrence period than currently presumed.