This ancient galaxy spun its spiral arms just 1.4 billion years after the Big Bang!
Key Takeaways:
- BRI 1335-0417 might be the oldest spiral galaxy ever identified, dating back 12.4 billion years.
- The galaxy’s spiral arms formed surprisingly early, challenging previous theories of galactic evolution.
- Star formation in BRI 1335-0417 is astonishingly rapid, creating stars at 5,000 times the Sun’s rate.
- The tightly coiled arms likely indicate true spirals rather than tidal tails from a collision.
- This discovery showcases ALMA’s ability to capture detailed galactic features in the distant universe.
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The delicate, curling arms in this image might belong to the oldest spiral galaxy ever identified. Captured as it existed just 1.4 billion years after the Big Bang, this galaxy predates the previous spiral galaxy record-holder by over a billion years.
This remarkable discovery was made by Takfumi Tsukui and Satoru Iguchi from Sokendai University in Tokyo, using the Atacama Large Millimeter/submillimeter Array (ALMA) radio telescope in Chile.
Named BRI 1335-0417, the galaxy showcases features typical of young spirals: a central bulge, a rotating gas disk, and what appear to be spiral arms. Spectral analysis reveals it’s producing stars at an astonishing rate—equivalent to 5,000 Suns per year—earning it the title of a starburst galaxy.
These characteristics suggest the galaxy is a young spiral entering its prime. Spiral arms are thought to form from waves of star creation sweeping through a galaxy’s disk. However, until now, such a well-developed spiral structure had never been observed when the universe was so young, long before its peak star formation era.
There is a slight possibility that the 10,000-light-year-long features are not traditional spiral arms but rather tidal tails—streams of stars pulled outward by gravitational interactions with another galaxy. However, the researchers note that tidal tails are usually larger and less tightly coiled than the arms seen in BRI 1335-0417, supporting the idea that these are genuine spiral arms.
