Chinese Astronomers Investigate Hot Gaseous Halo of NGC 7793 Using Spektr-RG and Chandra Observatories

Chinese astronomers, utilizing data from the Spektr-RG and Chandra space observatories, have conducted a study on the spiral galaxy NGC 7793, revealing insights into its hot gaseous halo. The galaxy, located approximately 12.2 million light-years away in the Sculptor Group, was analyzed using eROSITA and Chandra's ACIS instruments. The research team detected extraplanar X-ray emission, indicating the presence of a hot gaseous halo around NGC 7793. This halo is believed to be shaped by stellar feedback, a process where energy and matter ejected from stars influence the surrounding gas. The hot gas was found to have a temperature of about 0.18 keV and a mass of approximately 10 million solar masses, extending up to 19,500 light-years from the galaxy's center. The study also noted a peculiar dip in the radial profiles of NGC 7793, possibly due to a bubble-like structure or fluctuations in the intragroup medium. The astronomers suggest further investigation using the Hot Universe Baryon Surveyor (HUBS) X-ray microcalorimeter to gain a better understanding of the galaxy's hot circumgalactic medium.