Current theories say young galaxy clusters should be relatively cool compared to older ones. But researchers recently found a very young cluster that was shockingly hot.
Study author Dazhi Zhou says it's the first time a galaxy cluster this hot has been detected at such a young age.
"It was a pretty unexpected discovery, so we couldn't believe our detection was real," Zhou says.
A galaxy cluster is a collection of galaxies that resembles buildings in a city, where each galaxy is a different building. Our own galaxy, the Milky Way, is part of a cluster called the Local Group.
And the galaxy cluster at the heart of this new paper in Nature was formed about 12 billion years ago. The universe itself is only about 13.8 billion years old, making this cluster — SPT2349-56 — essentially a baby.
That's why they couldn't believe it when they discovered it was hotter than the surface of the sun.
"So this forces us to rethink our current understanding of how these large structures form and evolve in the universe," Zhou says.
His team doesn't yet know why this cluster is so hot. So Zhou says they need to collect more data to determine if this is an outlier or more common than scientists thought.
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