Scientists study the galaxy NGC 3640, known for its strange shape. A study using the Very Large Telescope shows that it may turn out to be a cannibal.
Predator galaxy NGC 3640
The unusual elliptical galaxy, which has swallowed up smaller galaxies in the past, seems to be approaching its next target.
New images from the Very Large Telescope (VLT) at the European Southern Observatory’s (ESO) Paranal Observatory reveal that the galaxy known as NGC 3640 may soon merge with a smaller galactic companion. Located 88 million light-years away from Earth, NGC 3640 is among a group of galaxies that vary in shape and size, including its unusual oval or egg shape.
The VLT images show that NGC 3640 has swallowed up other galaxies over the past few billion years, and now a smaller neighbor known as NGC 3641 lies in its path. Located just below NGC 3640 in the last image, NGC 3641 could eventually become the next meal of a large galaxy.
Galaxy merger processes
Over the course of their extremely long lives, galaxies change. While flying through space, they can steal gas and stars from other galaxies, or even absorb them and merge with them. After these events, galaxies can distort, as seen in the irregular shape of NGC 3640 and the scattered light around it.
When two galaxies approach each other, their gravitational attraction becomes stronger and stronger, causing them to eventually collide and merge into a single, larger galaxy. This, in turn, disrupts the original structures of both galaxies.
Fortunately, NGC 3641 may still have some time before it is swallowed up by a larger neighbor. Recent VLT images show no sign of NGC 3641 being distorted by an approaching galaxy, suggesting that NGC 3640 is not close enough to pose a threat yet.
Traces of past absorptions
Using new VLT images, astronomers from the Italian National Institute of Astrophysics managed to unravel NGC 3640’s past. The collision of two galaxies leaves “scars” on the surviving cosmic body, which usually contains some of the first stars created in the initial galaxy.
In this way, these stars serve as “fossil markers” of the original galaxy’s past, and this is how the team determined that NGC 3640 had previously absorbed other galaxies, the report said.
According to www.space.com
