While imaging the Fireworks galaxy, NASA’s NuSTAR X-ray observatory has spotted something quite weird. NuSTAR detected numerous mysterious bright light sources of X-ray light. These luminous sources were appearing as green and blue spots. Within a few days of observation, the blobs disappeared. A study published in the recent Astrophysical Journal offers a possible explanation regarding the appearance of these blobs that appeared and disappeared within the weeks and spotted near galaxy’s center. The main aim of NuSTAR examination was to observe a supernova, i.e., a massive star explosion. The green blob that is an ultraluminous X-ray source (ULX) appeared at the bottom of the galaxy didn’t appear during the first observation. But these green and blue blobs were spotted ten days later during the second observations. Chandra, NASA’s X-ray observatory, then looked again and it appeared that object ULX-4, had disappeared quickly.
Hannah Earnshaw, the lead author on the study and a postdoctoral researcher at Caltech, stated that ten days is a small amount of time for such a luminous object to appear. Further, she continued that NuSTAR is to observe more gradual changes, and it is rare to see a source multiple times in rapid succession. She stated they were fortunate enough to catch a source changing super quickly, and find it very exciting. The study suggests that chances are the light was emitting from a black hole that was consuming another object like a star. When any object gets too close to a black hole, it gets torn apart by gravity, and its debris is then pulled into a tight orbit surrounding the black hole.
According to NASA, the material present at the inner edge of the disk moves so fast that it heats up to around millions of degrees and then radiates X-rays. For instance, the Sun. The surface of the sun is like 10,000 degrees Fahrenheit. According to study the other possible explanations for the appearance of the green blob’s could be its source a neutron star. A neutron star is a super dense object that is a result of an explosion of a star that wasn’t big enough to create a black hole. Although mass of a neutron star is approximately equal to the sun, it’s only around the size of a big city. Hence, neutron star can pull in the materials and can cause debris to move fast in a disk. Earnshaw stated that the result observed is a step closer to understand some of the rarer and most extreme cases in which matter accumulated by black holes or neutron stars.