The Hubble captured a spectacular head-on collision between two galaxies that created a space triangle. Here’s everything you need to know about this unusual event.
What is the unusual space triangle?
A new image by NASA’s Hubble Space Telescope captured an unusual event. While the universe is full of fantastic activities, galaxies colliding are commonly seen. They are not universe-shattering or changing but, more of a tug-of-war. Depending on which galaxy has more strength backing it up, one galaxy may merge victorious. On other occasions, it can become a stellar material mishmash, giving rise to a brand new galaxy.
However, the new image captured by the Hubble has been puzzling scientists. A head-on collision between two galaxies formed a space triangle that’s bewildering. This duo is known as Arp 143 and it is comprised of two intersecting galaxies, NGC 2444 at the left and NGC 2445 at the right. The latter is a spiral star-forming galaxy with thousands of stars erupting to life. However, it has not been able to escape the former’s gravitational clutches. “This is a nearby example of the kinds of interactions that happened long ago. It’s a fantastic sandbox to understand star formation and interacting galaxies,” explained Elena Sabbi. Sabbi is with the Space Telescope Science Institute in Baltimore, Maryland.
The battle between galaxies
The collision between the two galaxies and the tug-of-war is causing NGC 2444 to start pulling gas from its partner, creating the space triangle. The new structure comprises newly minted stars. NGC 2444 is also responsible for extracting taffy-like stands of gas that is stirring the streamers of blue, young stars which are forming a scaffold. “Simulations show that head-on collisions between two galaxies are one way of making rings of new stars. Therefore, rings of star formation are not uncommon. However, what’s weird about this system is that it’s a triangle of star formation,” stated Julianne Dalcanton.
Dalcanton is an astronomer at the Flatiron Institute’s Center for Computational Astrophysics in New York. “Part of the reason for that shape is that these galaxies are still so close to each other and NGC 2444 is still holding on to the other galaxy gravitationally. NGC 2444 may also have an invisible hot halo of gas that could help to pull NGC 2445’s gas away from its nucleus. So they’re not completely free of each other yet, and their unusual interaction is distorting the ring into this triangle,” added Dalcanton.