These two merging galaxies anticipate the fate of the Milky Way

(CNN) — A new space image shows two entangled galaxies that will eventually merge into one in millions of years, and anticipates the ultimate fate of our own Milky Way.

The Gemini North telescope, located atop Maunakea in Hawaii, detected the interacting spiral galaxies some 60 million light-years away in the constellation Virgo.

The galaxy pair, NGC 4567 and NGC 4568, also known as the Butterfly galaxies, have just started colliding as gravity pulls them closer together.

This image from the Gemini North telescope in Hawaii reveals a pair of spiral galaxies, NGC 4568 (bottom) and NGC 4567 (top), at the point where they begin to collide and merge. The galaxies will eventually form a single elliptical galaxy in about 500 million years.

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 maintained its pinwheel shape. As the galaxies become intertwined, gravitational forces will give rise to multiple events of intense star formation. The original structures of the galaxies will change and become distorted.

Over time, they will dance around each other in smaller and smaller circles. This looping dance will pull and pull long streams of gas and stars, blending the two galaxies into something akin to a sphere.

As millions of years pass, this galactic entanglement will consume or disperse the gas and dust needed to trigger star birth, causing star formation to slow and eventually cease.

Observations of other galactic collisions and computational models have provided astronomers with further evidence that spiral galaxy mergers create elliptical galaxies.

Once the pair comes together, the resulting formation may more closely resemble the elliptical galaxy Messier 89, also located in the constellation Virgo. Once 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 merger

A similar galactic merger will occur when the Milky Way eventually collides with the Andromeda galaxy, our largest and closest galactic neighbor. NASA astronomers used Hubble data in 2012 to predict when a frontal collision could occur between the two spiral galaxies. It is estimated that the event will occur within about 4,000 to 5,000 million years.

Right now, a huge halo surrounding the Andromeda galaxy is colliding with the Milky Way’s halo, according to research based on data from the Hubble Space Telescope, which was published in 2020.

Andromeda’s halo, a large envelope of gas, extends 1.3 million light-years from the galaxy, about halfway to the Milky Way, and up to 2 million light-years in other directions.

Probably containing up to 1 trillion stars, this neighbor is about the same size as our large galaxy, and only 2.5 million light-years away. That may seem incredibly distant, but on an astronomical scale, that makes Andromeda so close that it’s visible in our sky during the fall. You can see it high in the autumn sky as a cigar-shaped patch of diffused light.

And if we could see Andromeda’s huge 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 end up in a new region of the galaxy, and Earth’s night sky could have some spectacular new views.