Science | July 29, 2017 5:00 am

Half of Everything in Our Galaxy Is Made of Atoms from Across the Universe

Exploding stars blew 50 percent of Milky Way atoms through space on 'solar winds.'

(NASA, ESA, NRAO/AUI/NSF and G. Dubner; University of Buenos Aires)

Half of all things on Earth originated on the other side of this universe.

A new simulation says big galaxies, like the Milky Way, contain 50 percent of matter that came from hundreds of thousands of light-years away. The atoms that formed our galaxy were blown across the universe on “galactic winds” fueled by exploding stars.

Previously, scientists didn’t think supernovae, the explosions caused by dying stars, were powerful enough to blast any matter that far. It turns out, galactic winds carrying atoms from one galaxy to another—a journey that could take several hundred million to 2 billion years—are strong enough, after all, New Scientist reports.

Northwestern University astronomy professor Claude-André Faucher-Giguère and his co-author Daniel Anglés-Alcázar used 3D models to re-create galactic formation, starting with the big bang. Their simulations showed that in galaxies with at least 100 billion stars, 50 percent of the matter was formed by galactic winds that carried atoms from neighboring celestial bodies.

According to New Scientist, the researchers believe the Milky Way galaxy was formed with matter from two dwarf galaxies 160,000 to 200,000 light years away, known as the large and small Magellanic clouds.