Astronomers may have observed a galaxy’s black hole delivery system in action, but a personal and cultural story behind the discovery adds even greater significance. A new study using data from NASA’s Chandra X-ray Observatory and Hubble Space Telescope outlines how a large black hole may have been delivered to the spiral galaxy NGC 4424 by a smaller galaxy.
What makes this discovery special for the Nagas is the name “Nikhuli” given to an elongated red object—a cluster of stars within NGC 4424. The name “Nikhuli,” inspired by the Tulini festive period in the Sumi language, honors the Sumi Naga community of Nagaland, India. This festive period celebrates a rich harvest, and the name “Nikhuli” is fitting as this star cluster plays a role in “delivering” a massive black hole to the center of the galaxy, much like a bountiful harvest being brought in.
Nikhuli, reportedly a Sumi Naga lady from Vishepu Village in Zunheboto District, Nagaland, is the namesake of this star cluster. Now settled in Australia, Nikhuli is married to an Australian astronomer who chose to name the cosmic object after his wife, linking the Naga culture with this scientific discovery.
The Nikhuli cluster is part of a larger cosmic event in the galaxy NGC 4424, which is located about 54 million light-years from Earth. The image of the galaxy shows a wide-field view about 45,000 light-years across, with the center of the galaxy believed to host a black hole with a mass between 60,000 and 100,000 Suns.
A closer look at NGC 4424 shows that Nikhuli, the cluster of stars, is likely the remnant of a smaller galaxy colliding with NGC 4424, having most of its stars stripped away as it was pulled by gravitational forces. Now elongated and stretched, Nikhuli is about 1,300 light-years from the center of NGC 4424.
The Chandra X-ray data indicates that matter from Nikhuli could be falling into a stellar-mass black hole, or possibly into a more massive black hole between 40,000 and 150,000 solar masses. This process suggests that Nikhuli is playing a vital role in delivering black holes to NGC 4424.