Ancient spiral galaxy baffles astronomers (+video)
Using data from the Hubble telescope, scientists have found the oldest spiral galaxy in the universe, a galaxy that, according to current models, isn't supposed to exist.
Astronomers have discovered the universe's most ancient spiral galaxy yet, a cosmic structure that dates back roughly 10.7 billion years, a new study reveals.Skip to next paragraph
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Movie credit: Fabio Governato / Univ. of Washington
The galactic find, discovered by researchers using NASA's Hubble Space Telescope, comes as something of a surprise. Other galaxies from such early epochs are clumpy and irregular, not strikingly symmetrical like the newfound spiral, which broadly resembles our own Milky Way.
"The fact that this galaxy exists is astounding," study lead author David Law, of the University of Toronto, said in a statement. "Current wisdom holds that such ‘grand-design’ spiral galaxies simply didn’t exist at such an early time in the history of the universe."
Scanning ancient galaxies
Law and his colleagues used Hubble to snap photos and study the properties of about 300 distant galaxies. The newfound galaxy, which goes by the name BX442, was the only spiral in the bunch, researchers said.
BX442's light has taken about 10.7 billion years to reach us, meaning astronomers are now seeing it as it looked just 3 billion years after the Big Bang that created the universe. [Big Bang to Now in 10 Easy Steps]
Today, spiral galaxies like our own Milky Way are common throughout the cosmos. But that wasn't the case long ago, when galaxy collisions were much more common, gas raining in from the intergalactic medium fed more dramatic star formation and black holes grew faster than they do now, researchers said.
"The vast majority of old galaxies look like train wrecks," said co-author Alice Shapley of UCLA. "Our first thought was, why is this one so different, and so beautiful?"
To learn more about BX442, the team employed a different telescope, the Keck Observatory atop Hawaii's dormant Mauna Kea volcano. They used a Keck spectrograph to study light emitted from 3,600 targets in and around the Milky Way.