SN 2024ggi was a Type IIsupernova event that occurred in the spiral galaxy NGC 3621 around 6.6 Mpc from Earth in the constellation of Hydra. It was discovered using ATLAS (Asteroid Terrestrial-impact Last Alert System) on the 11th of April 2024 at 3.21 UTC.[1] It is one of the closest supernovae discovered to date. The explosion produced 2 × 10^51 ergs of energy. The star that produced this explosion had around 15 solar masses and a radius of around 500 solar radii.
The Las Campanas and Gemini South Observatories helped determine much of the properties and characteristics of SN 2024ggi through optical photometry and spectroscopy during its nebular phase. This was to determine features of the supernova such as the progenitor stars mass, possible asymmetries in the supernova ejecta and possible interactions with its circumstellar disks. These studies showed that the progenitor star was a zero-age main sequence (ZAMS) star that had a mass between 12 and 15 solar masses and a radius of 517 solar radii. The star also possibly had a mass loss rate of 4x10^-3 solar masses per year (assuming 10km/s stellar winds).[2][3] The line profiles of SN 2024ggi exhibit only minor changes, suggesting that the ejecta was mostly symmetrical. These line profiles also showed that a clump of oxygen-rich material existed that was moving towards the observer. The explosion synthesized around 0.05-0.06 solar masses of nickel-56.[4]
There seems to have been interaction between the supernova ejecta and the surrounding dense circumstellar material. The ejecta had engulfed the circumstellar material, causing the ejecta to emerge with a hydrogen-rich envelope.[5]
Discovery
SN 2024ggi was discovered on the 11th of April in the year 2024. Roughly 5.8 hours after the explosion, the Kilonova finder (Kinder) preformed an early-phase, high-cadence, and multiband photometric follow-up observation. Theses observations showed that between 13.8 and 18.8 hours after the explosion, SN 2024ggi became bluer, indicating that there was a wind shock breakout (SBO) scenario happening. At around 17 hours, it showed flash features of high-ionization species such as Balmer lines, He i, C iii, and N iii.[3]
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
