A new image of a colliding galaxy previews the galaxy’s fate
A new telescope image shows two entangled galaxies that will eventually merge millions of years from now — and previews the eventual, common fate of our own galaxy.
The Gemini North Telescope, atop Maunakea in Hawaii, observed a pair of 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 Galaxy, have recently begun 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.
the weather
A new image of a colliding galaxy previews the galaxy’s fate
August 10, 2022 at 6:58 p.m. posted. EDT
This image from the Gemini North Telescope in Hawaii reveals a pair of interacting spiral galaxies — NGC 4568 (bottom) and NGC 4567 (top) — as they collide and merge. The galaxies will eventually form a single elliptical galaxy in about 500 million years.
By Ashley Strickland, CNN
A new telescope image shows two entangled galaxies that will eventually merge millions of years from now — and previews the eventual, common fate of our own galaxy.
The Gemini North Telescope, atop Maunakea in Hawaii, observed a pair of 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 Galaxy, have recently begun 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 centers of the two galaxies are currently 20,000 light-years apart, and each galaxy retains its pinwheel shape. As the galaxy becomes more involved, gravitational forces will cause many intense star formation events. The basic structures of galaxies will change and distort.
Over time, they will dance around each other in smaller and smaller circles. This tightly looped dance will pull out long streams of gas and stars, merging the two galaxies into something that looks like a sphere.
As millions of years pass, this galactic entanglement will eat up or disperse the gas and dust needed to start star birth, slowing and eventually stopping star formation.
Observations of other galaxy collisions and computer modeling have given astronomers more evidence that mergers of spiral galaxies lead to the formation of elliptical galaxies.
Once the pair merges, the resulting formation can look like the elliptical galaxy Messier 89, also located in the constellation Virgo. Once Messier 89 lost most of the gas needed to form stars, very few stars were born. Now, the Milky Way is home to old stars and ancient clusters.
The afterglow of a supernova first detected in 2020 is also visible as a bright spot in one of NGC 4568’s spiral arms in the new image.
Galaxy Merger
A similar galactic merger will be revealed when the Milky Way galaxy eventually collides with its largest and closest galactic neighbor, the Andromeda galaxy. Astronomers at NASA used Hubble data in 2012 to predict when two spiral galaxies might collide. This event is estimated to occur in about 4 billion to 5 billion years.
Right now, according to research based on Hubble Space Telescope data published in 2020, a giant halo surrounding the Andromeda galaxy is actually colliding with the Milky Way’s halo.
Andromeda’s halo, a large envelope of gas, extends 1.3 million light-years from the Milky Way, about half as far as the Milky Way, and 2 million light-years in other directions.
This neighborhood, which contains perhaps 1 trillion stars, is about the same size as our own Milky Way and is only 2.5 million light-years away. This may seem incredibly distant, but on an astronomical scale, this brings Andromeda close enough to be visible in our autumn sky. You can see it as a faint cigar-shaped light, high in the sky during autumn.
And if we could see Andromeda’s giant halo, invisible to the naked eye, it would be three times the width of the Big Dipper than anything else in our sky.
Scientists at NASA say our solar system isn’t likely to be destroyed when the Milky Way and Andromeda merge, but the Sun could move into a new region of the galaxy — and Earth’s night sky could have some spectacular new views.
