NASA’s James Webb Space Telescope has detected a galaxy that formed around 600 million years after the big bang and is similar in mass to our Milky Way galaxy at that stage. The galaxy, nicknamed “Firefly Sparkle,” was discovered through a natural effect called gravitational lensing, which enhanced its appearance.
Researchers led by Lamiya Mowla, an assistant professor at Wellesley College, used Webb’s high-resolution infrared light to image the galaxy in detail. They were able to resolve 10 distinct star clusters, each emitting significant amounts of light. The galaxy is believed to be on the smaller side and is still forming.
The team reconstructed what the galaxy might have looked like if it weren’t stretched and found that it resembled an elongated raindrop with two star clusters at the top and eight at the bottom. They also discovered that clumps of actively forming stars are surrounded by diffuse light from other unresolved stars.
Webb’s data shows that the Firefly Sparkle galaxy is not like other galaxies detected at this time period, which are significantly more massive. Instead, it is witnessing a galaxy being assembled “brick by brick.” The team’s research relied on data from Webb’s Canadian NIRISS Unbiased Cluster Survey (CANUCS), which includes near-infrared images and spectra.
The discovery provides new insights into the formation of galaxies in the early universe. The Firefly Sparkle galaxy is only 6,500 light-years away from its first companion, and its second companion is separated by 42,000 light-years. The team believes that these interactions may influence how the galaxy builds mass over billions of years.
This discovery highlights the importance of the James Webb Space Telescope in solving mysteries about our solar system, distant worlds, and the universe’s origins.
Source: https://science.nasa.gov/missions/webb/found-first-actively-forming-galaxy-as-lightweight-as-young-milky-way