used by astronomers CSIRO's Australian Telescope Compact Array captured the most detailed radio images ever seen of the 47-member Tukanae star cluster, the second brightest globular cluster in the night sky.
paduano other. identified new radio sources (white squares) at the center of 47 Tucanae (red circles).Image credit: Paduano other., doi: 10.3847/1538-4357/ad0e68.
Tucanae 47, also known as NGC 104, is a massive ancient globular cluster located approximately 15,300 light-years south of the constellation Tucanae.
At about 120 light-years in diameter, this cluster is so large that despite its distance, it appears to be about the same size as the full moon.
Home to millions of stars, 47 Tucanae is one of the brightest and most massive globular clusters known and is visible to the naked eye.
“Globular clusters are very old, gigantic balls of stars found around the Milky Way. They are incredibly dense, with tens to millions of stars packed together inside the ball.” said Dr. Arash Bahramian, astronomer at the Curtin University Node of the International Center for Radio Astronomy Research (ICRAR).
“Our images are of 47 Tucanae, one of the most massive globular clusters in the galaxy. It has more than a million stars and a very bright, very dense core.”
The ultra-high-sensitivity radio images of 47 species of Tucanidae were created from more than 450 hours of observations with CSIRO's Australian Telescope Compact Array (ATCA).
“The 47 Tukanae are visible to the naked eye and were first cataloged in the 1700s,” Dr. Bahramian said.
“By imaging in great detail, we were able to discover an incredibly faint radio signal at the center of the cluster that was previously undetectable.”
“The detection of the signal is an exciting discovery and can be attributed to one of two possibilities,” said Dr. Alessandro Paduano, also from ICRAR's Curtin University Node.
“First, the 47 Tukanae may contain black holes with masses between the supermassive black holes at the centers of galaxies and the stellar black holes created by collapsing stars. .”
“Intermediate-mass black holes are thought to exist within globular clusters, but they have not yet been clearly detected.”
“If this signal turns out to be a black hole, it would be a very important discovery and the first radio detection of a black hole in a star cluster.”
The second possible source is a pulsar. This is a rotating neutron star that emits radio waves.
“This is an interesting discovery scientifically, as a pulsar so close to the center of a cluster could be used to search for as yet undetected central black holes,” Paduano said.
of result Published in astrophysical journal.
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Alessandro Paduano other. 2024. Ultra-deep ATCA imaging of 47 Tucanae reveals a central, compact radio source. APJ 961, 54; doi: 10.3847/1538-4357/ad0e68
Source: www.sci.news
