When most people think of galaxies, the first image that likely comes to mind is the disk and spiral shape of the Milky Way galaxy. However, the galaxy NGC 6240, captured by the Hubble space telescope, presents an entirely different portrait.
Possibly formed by the merger of two galaxies, NGC 6240 contains two black holes instead of the standard one black hole present at the center of a galaxy. This has resulted in NGC 6240 resembling a giant butterfly.
Galaxy NGC 6240, the Giant Butterfly in the Sky
Due to a combination of the merger between the black holes and gases ejected from stars forming within the merging galaxy, the stellar winds force the gases away from the black holes. In turn, this resulted in the galaxies forming a giant butterfly shape.
Observing the formation of this new galaxy has provided valuable insight into our own galaxy. This is because the researchers believe that it is likely the collision of two galaxies formed the Milky Way.
By utilizing three separate telescopes, including the well-known Hubble telescope, the researchers closely examined what was happening within the merging galaxies.
“This is the first galaxy in which we can see both the wind from the two supermassive black holes and the outflow of low ionization gas from star formation at the same time,” states Francisco Müller-Sánchez, the study author.
As this new galaxy is forming, stars are also quickly appearing. The gases from the star formation are believed to contribute to the stellar winds in one portion of the galaxy. As the two black holes continue circling one another, stellar winds are emitted here as well. This is another contributing factor to the butterfly shape noticed by the telescopes.
As scientists continue to observe the merger of these two galaxies, they are hoping to discover more things about it and our own Milky Way as well.
Studying NGC 6240 is also providing an unique insight for researchers due to its double black holes. With thousands of years left to observe, NGC 6240 will present generations of scientists with data to apply to the understanding of galaxy formation.
A study paper with the current results is available in the journal Nature.
Image Source: Wikimedia