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ABSTRACT We report on analysis using the JWST to identify a candidate progenitor star of the Type II-plateau (II-P) supernova SN 2022acko in the nearby, barred spiral galaxy NGC 1300. To our knowledge, our discovery represents the first time JWST has been used to localize a progenitor system in pre-explosion archival Hubble Space Telescope (HST) images. We astrometrically registered a JWST NIRCam image from 2023 January, in which the SN was serendipitously captured, to pre-SN HST F160W and F814W images from 2017 and 2004, respectively. An object corresponding precisely to the SN position has been isolated with reasonable confidence. That object has a spectral energy distribution (SED) and overall luminosity consistent with a single-star model having an initial mass possibly somewhat less than the canonical 8 M⊙ theoretical threshold for core collapse (although masses as high as 9 M⊙ for the star are also possible); however, the star’s SED and luminosity are inconsistent with that of a super-asymptotic giant branch star that might be a forerunner of an electron-capture SN. The properties of the progenitor alone imply that SN 2022acko is a relatively normal SN II-P, albeit most likely a low-luminosity one. The progenitor candidate should be confirmed with follow-up HST imaging at late times, when the SN has sufficiently faded. This potential use of JWST opens a new era of identifying SN progenitor candidates at high spatial resolution.
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This content will become publicly available on April 2, 2026
Enthalpies and Entropies of Activation for sn- 1/ sn- 2 Acyl Chain Loss in Glycerophospholipid Anions via Dipolar DC Kinetics
- Award ID(s):
- 2304386
- PAR ID:
- 10589975
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Journal of the American Society for Mass Spectrometry
- Volume:
- 36
- Issue:
- 5
- ISSN:
- 1044-0305
- Page Range / eLocation ID:
- 1041 to 1051
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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