Astronomers map ancient supernova SN 1181 revealing new details of its expansion

Astronomers have mapped the remnants of supernova SN 1181, which exploded in 1181 CE. Using the Keck Cosmic Web Imager, they created a three-dimensional map showing the expanding material, revealing new details about its structure and movement. The study found that the supernova's ejecta is expanding at about 1,000 kilometers per second. This measurement confirms the connection between SN 1181 and its remnant, Pa 30, and pinpoints the explosion to the year 1181. Researchers also discovered asymmetry in the remnant and a large cavity around the central white dwarf. The formation of thin filaments remains unclear, suggesting further investigation is needed. The findings were published in The Astrophysical Journal Letters.