In our neighboring sister galaxy of Andromeda, NASA’s Chandra X-ray observatory has identified 26 black hole candidates, the largest number to date in a galaxy outside our own. Using over 150 images spanning more than 13 years, Chandra has been able to observe this large cluster of black holes that scientists believe to be just the tip of the iceberg. The reason why this finding is so exciting to researchers is that black holes generally will not have close companions and will be invisible to detection.
The black holes found by Chandra belong to the stellar mass category, meaning they formed from the deaths of extremely large stars and usually have masses 5 to 10 times that of our sun. As material is pulled from nearby stars and heated up to create radiation before being engulfed by the black hole, scientists are able to use this radiation to detect these otherwise invisible objects. Researchers engaged in a couple steps to identify these clusters as a stellar mass system in the Andromeda galaxy.
First, utilizing a technique focusing on the brightness and variability of X-ray sources in Chandra’s data, astronomers were able to classify the black holes as a stellar mass system in the Andromeda galaxy as opposed to supermassive black holes elsewhere. Second, analyzing the X-ray sources, researchers noted two important characteristics: they were brighter than a certain high level of X-rays and possessed a distinct color. Chandra’s advanced X-ray technology played a vital role in locating the black holes that may have otherwise gone unnoticed.
One critical aspect to the black hole cluster’s research was observing over 13 years of images from Chandra. This long exposure allowed astronomers to test whether the objects were black holes or neutron stars, which possess similar characteristics. Using data provided by Chandra, scientists had previously found 9 black holes and with this new cluster the total has increased to 35.
Researchers are extremely excited about this discovery that they have spent years searching for. While black holes remain a mysterious phenomena, the findings made by the Chandra X-ray observatory may play a key role in unraveling more secrets about black holes and the galaxies they reside in.
Filed under: Current Events, Newsletter, Science Facts | Tagged: Andromeda Galaxy, Black Holes, Chandra X-Ray Observatory, NASA, X-Rays | Leave a comment »
