New images from NASA’s James Webb Space Telescope (JWST) have revealed that a well-known ancient galaxy has an eclipsed companion that’s abundant with star formation.
JWSTThe initial target was SPT0418-47, one of the brightest dusty star-formers galaxies in the early universe. Since it is an extremely distant galaxy – it is about 12 billion light-years from Earth – its light is bent and amplified by the gravity of another galaxy in the foreground (located between SPT0418-47 and the space telescope), creating an almost perfect circle image called a Einstein ring.
Using the JWST, astronomers were able to get a clearer view of SPT0418-47 and spotted a curious blob of light shining near the outer edge of the galaxy. The blob turns out to represent a companion galaxy previously eclipsed by light from the foreground galaxy, according to A declaration (opens in a new tab) from Cornell University.
Related: 12 amazing discoveries from the James Webb Space Telescope
“We found this galaxy to be super-chemically abundant, which none of us expected,” Bo Peng, the study’s lead author and a PhD student in astronomy at Cornell, said in the statement. “JWST is changing the way we view this system and opening new horizons for studying how stars and galaxies formed in the early universe.”
Previous observations of SPT0418-47 using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile contained cues from the mate, which at the time were interpreted as random noise, the researchers said.
Using the JWST, the researcher discovered that the companion galaxy, called SPT0418-SE, is about 16,000 light-years away from SPT0418-47. By comparison, the Magellanic Clouds – a pair of companion dwarf galaxies of the Milky Way — are located about 160,000 light years from us.
The proximity of SPT0418-47 and SPT0418-SE suggests that these galaxies are bound to interact or merge with each other Ultimately. In turn, this galactic pair could shed light on how early galaxies evolved into larger galaxies, given that SPT0418-47 is thought to have formed when the universe was just 1.4 billion years old. , according to the press release.
Interestingly, SPT0418-SE would have already welcomed several generations of stars, despite its young age. Both galaxies have mature metallicity – or large amounts of elements like carbon, oxygen and nitrogen which are heavier than hydrogen and helium – which is similar to the sun. However, our sun is 4.5 billion years old and inherited most of its metals from previous generations of eight-billion-year-old stars, the researchers said.
“We see the remains of at least two generations of stars to have lived and died during the first billion years of the universe’s existence, which is not what we usually see,” said study co-author Amit Vishwas, associate researcher at Cornell. Center for Astrophysics and Planetary Sciences, in the same press release.
“We speculate that the star formation process in these galaxies must have been very efficient and started very early in the universe, especially to explain the measured abundance of nitrogen relative to oxygen, since this ratio is a reliable measure of how many generations of stars have lived and died,” Vishwas said.
The new findings were published on February 17 (opens in a new tab) in the Astrophysical Journal Letters.
Follow us on twitter @Spacedotcom (opens in a new tab) Or on Facebook (opens in a new tab).