Skip to main content

Impending collision of Milky Way with other galaxy is already creating new stars

A map of the Milky Way.
A newfound cluster of young stars (blue star) sits on the periphery of the Milky Way. These stars probably formed from material originating from neighboring dwarf galaxies called the Magellanic Clouds. D. Nidever; NASA

We know that in around 2 billion years’ time, our galaxy will collide with a nearby satellite galaxy, the Large Magellanic Cloud (LMC). This collision will be so dramatic that it will awaken the black hole at the heart of our galaxy, causing it to gorge on nearby matter and balloon to ten times its current size. The LMC is a fairly small galaxy, but it is rich in dark matter so it has a large mass, causing the collision between the two galaxies to be catastrophic.

For now, though, the interaction of the two galaxies isn’t destructive — it is actually creating new stars. Using data from the Gaia spacecraft, researchers looked for rare blue stars and the clusters of stars that move along with them in our galaxy. Once they had identified and removed known star clusters, they found one remaining cluster on the far edges of the Milky Way.

“It’s really, really far away,” primary discoverer Adrian Price-Whelan, a research fellow at the Flatiron Institute’s Center for Computational Astrophysics in New York City, said in a statement. “It’s further than any known young stars in the Milky Way, which are typically in the disk. So right away, I was like, ‘Holy smokes, what is this?’”

By analyzing the elements found in the stars in the cluster, the researchers realized that they were likely formed from particles from outside of our galaxy. As the mystery cluster is located near to a river of gas called the Magellanic Stream which flows from the Large and Small Magellanic Clouds and reaches toward the Milky Way, they believe these other galaxies are the source of the materials which formed the stars.

“This is a puny cluster of stars — less than a few thousand in total — but it has big implications beyond its local area of the Milky Way,” Price-Whelan said. One implication is that the LMC might be closer to the Milky Way than previously believed.

“If the Magellanic Stream is closer, especially the leading arm closest to our galaxy, then it’s likely to be incorporated into the Milky Way sooner than the current model predicts,” David Nidever, assistant professor of physics at Montana State University in Bozeman, said in the statement. “Eventually, that gas will turn into new stars in the Milky Way’s disk. Right now, our galaxy is using up gas faster than its being replenished. This extra gas coming in will help us replenish that reservoir and make sure that our galaxy continues to thrive and form new stars.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Hubble captures a peculiar galaxy pulled out of shape by a nearby satellite
hubble ngc4455 berenice hair a rival to the milky way

A spiral galaxy named NGC 772, captured by the NASA/ESA Hubble Space Telescope. This image was first shared on 11th November 2019. ESA/Hubble & NASA, A. Seth et al.

This elegant image was captured by the Hubble Space Telescope, showing a galaxy called NGC 772 which is located 130 million light-years away in the constellation Aries.

Read more
Astronomers discover a cosmic Yeti: A massive galaxy from the early universe
massive galaxy cosmic yeti 05 1

An artist’s impression of what a massive galaxy in the early universe might look like. The galaxy is undergoing an explosion of star formation, lighting up the gas surrounding the galaxy. Thick clouds of dust obscure most of the light, causing the galaxy to look dim and disorganized, very different from galaxies seen today. James Josephides/Christina Williams/Ivo Labbe

Astronomers have spotted evidence of a massive and ancient galaxy, so old and so large that they compared finding it to spotting a cosmic Yeti.

Read more
Collisions of neutron stars create element that makes fireworks sparkle
neutron star merger strontium artist  s impression of emerging from a

An artist’s impression of strontium emerging from a neutron star merger. ESO/L. Calçada/M. Kornmesser

When massive neutron stars collide, they don't only produce dazzling light, bursts of gamma rays, and magnetic fields trillions of times stronger than the field on Earth. Scientists from the European Southern Observatory (ESO) have found that they can also create heavy elements like strontium, finally answering a long-standing puzzle about the origin of certain elements found on Earth.

Read more