While observing a large superstar in the Fireworks Galaxy, researchers accidentally captured images of a short, bright spot in the same galaxy that did not originate from the supernova. This spot was not visible at NASA's initial NuSTAR observation, but was observed a little over a week later at subsequent observation by the space agency's Chandra X-ray Observatory.
The image shared by NASA (above) shows three clearly bright blue / green and green spots located in NGC 6946, also known as the Fireworks Galaxy. According to a new study by the Space Agency, researchers have used the NuSTAR Space Observatory to examine the blue-green supernova located in the upper right corner of the image. The supernova is the result of a major explosion of a star.
The green spot near the center of the galaxy was not visible when NuSTAR first observed the supernova. However, the spot appeared 1
Although other ULX spots have been observed, NASA explains that ULX-4 is quite rare because of how short it is seen. Most of the ULXs are described as extended over long periods of time. However, it is believed that this last spot is probably the result of a black hole decimating a small star, leading to what was essentially a brief space breakthrough.
Leading author of the study Hannah Earnshaw explains:
Ten days is a really short time for such a bright object to appear. Usually with NuSTAR we observe more gradual changes in time and we do not often observe the source repeatedly in rapid succession. In this case, we were fortunate to catch a source that is changing extremely fast, which is very exciting.