A new image from the Gemini North telescope shows two colliding galaxies that will eventually merge a million years from now — and predicts the eventual, similar fate of our own Milky Way galaxy.
The telescope, located on the summit of Maunakea in Hawaii, spotted interacting spiral galaxies about 60 million light-years away in the constellation Virgo.
The galactic pair NGC 4567 and NGC 4568, also known as the Butterfly galaxies, have started to collide as gravity pulls them together.
In 500 million years, the two cosmic systems will complete their merger to form a single elliptical galaxy.
At this early stage, the two galactic centers are currently 20,000 light-years apart and each galaxy has retained its weathervane shape.
As galaxies become closer together, gravitational forces will lead to multiple events of intense star formation. The original structures of galaxies will change and distort.
Over time, they will dance around each other in circles that get smaller and smaller. This tight loop dance will pull and extend long streams of gas and stars, blending the two galaxies into something that resembles a sphere.
As millions of years pass, this galactic tangle will consume or disperse the gas and dust needed to trigger star birth, causing star formation to slow and eventually stop.
Observations of other galactic collisions and computer modeling have provided astronomers with more evidence that spiral galaxy mergers create elliptical galaxies.
Once the pair merges, the resulting formation may look more like the elliptical galaxy Messier 89, also located in the constellation Virgo.
Since Messier 89 lost most of the gas needed to form stars, very little star birth occurred. Now the galaxy is home to older stars and ancient clusters.
The afterglow of a supernova, first detected in 2020, is also visible in the new image as a bright spot in one of the spiral arms of the galaxy NGC 4568.
Milky Way Fusion
A similar galactic merger will take place when the Milky Way collides with the Andromeda Galaxy, our closest and largest galactic neighbor.
NASA astronomers used Hubble data in 2012 to predict when a head-on collision between the two spiral galaxies might occur. Estimates project that the event will happen in about 4 billion to 5 billion years.
Right now, a massive halo surrounding the Andromeda Galaxy is actually colliding with the Milky Way’s halo, according to research based on Hubble Space Telescope data published in 2020.
Andromeda’s halo, a large envelope of gas, extends 1.3 million light-years from the galaxy, almost halfway to the Milky Way, and up to two million light-years in other directions.
This neighbor, which likely contains up to a trillion stars, is similar in size to our large galaxy and just 2.5 million light-years away.
This may seem incredibly far away, but on an astronomical scale, this makes Andromeda so close that it’s visible in our autumn sky in the Northern Hemisphere.
You can see it as a bit of diffused cigar-shaped light, high in the sky during autumn.
And if we could see Andromeda’s massive halo, which is invisible to the naked eye, it would be three times the width of the constellation Ursa Major, which dwarfs anything else in our sky.
NASA scientists said our Solar System is unlikely to be destroyed when the Milky Way and Andromeda merge, but the Sun could be kicked into a new region of the galaxy — and Earth’s night sky could have some spectacular new vistas.
Source: CNN Brasil
