Study Suggests a Stellar-Mass Black Hole Powers NGC 4490 ULX-8

Key facts

• Researchers from the Indian Institute of Astrophysics (IIA), the Raman Research Institute, and other institutions analysed 24 years of X-ray data to study the ultraluminous X-ray source (ULX) known as NGC 4490 ULX-8.
• The study utilised archival and recent observations from the Chandra, XMM-Newton, and Swift space-based X-ray telescopes collected between 2000 and 2024.
• Findings suggest that ULX-8 is most likely powered by a stellar-mass black hole undergoing intense accretion.
• The research team included members from IIA, the Raman Research Institute, the Indian Institute of Science Education and Research (IISER) Mohali, and the Inter-University Centre for Astronomy and Astrophysics (IUCAA).
• Future studies of such systems are expected to be supported by the European Space Agency's (ESA) NewAthena mission and India's proposed XSat mission.