This newly-released image shows us a spoked-wheel galaxy with a lot of natural charm. Called NGC 1291, the aforementioned galaxy, which is roughly 12 billion years old, lurks 33 million light-years away from Earth in the constellation of Eridanus.
Using the Spitzer Space Telescope, astronomers have seen the ring extending around the galaxy’s central core in unprecedented clarity. However, the ring itself is a bit of a cosmic quandary. Given the galaxy’s ripe old age, it’s unusual, to say the least, to see such a large amount of starformation activity taking place at this stage of galaxy evolution.
“The rest of the galaxy is done maturing,” notes Kartik Sheth of the National Radio Astronomy Observatory of Charlottesville, Virginia. “But the outer ring is just now starting to light up with stars.”
In addition to the ring, NGC 1291 also boasts an expansive central bar (said bar can be seen in this Spitzer image as the blue, s-shaped structure), where a huge number of stars lie. The stars inhabiting the bar, which formed early on in the galaxy’s evolution, are born as the result of Lindblad resonance. Simply put, the bar “churns material around, forcing stars and gas from their original circular orbits into large, non-circular, radial orbits. This creates resonances — areas where gas is compressed and triggered to form new stars.”
NASA’s Chandra team expands:
See a larger image here.