Study of supernova SN 2023zcu aids cosmic distance measurement

Indian researchers have contributed to a groundbreaking study of supernova SN 2023zcu, discovered on December 8, 2023, at the edge of the spiral galaxy NGC 2139, approximately 90.7 million light-years away. The study, published in The Astrophysical Journal, provides detailed insights into the supernova's evolution and its role in estimating cosmic distances.

Supernova SN 2023zcu belongs to the Type IIP category, which occurs when massive red supergiant stars exhaust their nuclear fuel and collapse. This type is characterized by a 'plateau' phase in its light curve, where brightness remains stable due to hydrogen recombination. Researchers used the Expanding Photospheric Method (EPM) to calculate the supernova's distance at 27.8 megaparsecs (Mpc), offering precise measurements critical for understanding the local universe.

The study also modeled the bolometric luminosity to estimate the progenitor star's properties, revealing a mass approximately 12 times that of the Sun and an explosion energy of 2 × 10⁵¹ ergs. Spectroscopic observations showed the formation of new elements like iron, calcium, and magnesium during the explosion, highlighting the supernova's role in cosmic recycling.

This research was led by scientists from Aryabhatta Research Institute of Observational Sciences (ARIES), an autonomous institute under India's Department of Science and Technology, in collaboration with international experts. Frequent monitoring of the supernova's phases has enhanced understanding of these powerful cosmic events.

The findings not only deepen knowledge of stellar evolution but also refine methods for measuring distances across the universe, aiding future astronomical studies and discoveries.

Source: Press Information Bureau (Govt. of India) press release, 12 JUN 2026. https://www.pib.gov.in/PressReleasePage.aspx?PRID=2272106