AstroNote 2024-107

SN 2024ggi (ATLAS24fsk, GOTO24aig) is a very young supernova in NGC 3621 discovered by the ATLAS survey on 2024-04-11 03:22:35 UT at orange-ATLAS = 18.915 +/- 0.078 and reported to TNS and AstroNotes (Tonry et al. and Srivastav et al. AstroNote 2024-100). Additional observations by GOTO (Killestein et al. Astronote 2024-101), Kinder (Chen et al. Astronote 2024-102), and LIONS (Zhai et al. AstroNote 2024-104) show a fast rise of the flux.

Early optical spectroscopy by LIONS (Zhai et al., TNS classification report and AstroNote 2024-104) and SCAT (Hoogendam et al. Astronote 2024-103) reveals that this transient is a very young SN II with flash features due to SN-CSM interaction.

S. Srivastav et al. (AstroNote 2024-100) and Yang et al. (AstroNote 2024-105) discuss a possible progenitor star visible in archival DESI Legacy Survey and HST imaging.

Here, we report the identification of the SN likely progenitor star in the near-IR using archival imaging and catalogs of the VISTA Hemisphere Survey (McMahon et al. 2020). The VHS source VHS J111822.09-325015.2 is found at only 0.06 arcsec from the supernova position reported by Tonry et al. (TNS discovey report) and Srivastav et al. (AstroNote 2024-100), with point-source aperture-corrected Vega magnitudes (2.0" diameter) Jap3 = 19.74 +/- 0.17, Ksap3 = 18.44 +/- 0.30. Using the VHS recommended Vega to AB magnitude conversions, we obtain in the AB system Jap3 (AB) = 20.65 +/- 0.17,  Ksap3 (AB) = 20.27 +/- 0.30, that at the distance of NGC 3621 and without considering low Milky Way extinction corrections in the near-IR give absolute magnitudes of about -8.5 and -8.9 in J and Ks, respectively.

A figure showing the SN 2024ggi position on the VHS J and Ks images is attached.

Follow-up observations are encouraged.