A team of astronomers used the Hubble Space Telescope to learn more about one of the fascinating objects in the known universe: the Umbrella Galaxy, also known under the scientific name of NGC 4651.
The look of the galaxy is quite remarkable, as its large spirals extend across a significant area. At first sight, it is remarkable that there is so much free space at the object, but new research argues that this trait is justified by a dark secret as Umbrella may have consumed a smaller galaxy in the past, an act that would also explain the impressive size.
Researchers theorize that at some point in the past, there were two galaxies in the area, with one being large while the other one was smaller. The small one used to orbit around the other galaxy until it came too close and was caught by the powerful gravitational pull of the bigger object.
The dark secret of the Umbrella Galaxy
As time passed, the two galaxies became one as the smaller one was absorbed. This process would have been quite spectacular to see, but it took place a long time ago. It is worth pointing out that the name of the galaxy is inspired by the traces of an umbrella-like structure that seem to come from the galactic core. Current data infers that the massive structure has a radius of more than 100,000 light-years. Stripped stars can be seen on the left side of the galaxy, offering a remarkable vista.
According to the researchers, the umbrella structure proves that a smaller galaxy has been consumed. During the process known as gravitational streaming, parts of the small galaxy were ripped away, leading to the formation of a structure which is called tidal stream.
Unlike other galaxies, it is possible to observe the Umbrella Galaxy with the help of amateur telescopes, an activity that can be done easily from the comfort of your home.