Astronomers have made a groundbreaking discovery using the James Webb Space Telescope (JWST), mapping out the history of stars in a low-mass dwarf galaxy. This galaxy, known as Wolf–Lundmark–Melotte (WLM), bears a striking resemblance to galaxies that existed in the early universe. By studying WLM, scientists hope to gain a better understanding of how star formation rates have evolved over the past 13 billion years.
Led by astronomer Kristen McQuinn from Rutgers University-New Brunswick, the team utilized the powerful capabilities of the JWST to capture the most accurate image of WLM to date. Situated approximately 3 million light-years away from our Milky Way, WLM is not only actively forming stars but also hosts ancient stars that are believed to have originated around 13 billion years ago, just 800 million years after the Big Bang.
Low-mass galaxies like WLM are of great interest to researchers because they were thought to have dominated the early universe. By studying these galaxies, scientists can gain insights into early star formation rates. The JWST’s ability to observe faint galaxies has allowed astronomers to delve deeper into these celestial bodies than ever before.
WLM, located at the edge of the Milky Way’s local group, has managed to maintain its stellar population due to its isolated position. Unlike other galaxies that have been influenced by gravitational forces from neighboring galaxies, WLM has remained relatively undisturbed. This, coupled with its dynamic nature and abundance of gas and dust, makes WLM an intriguing target for astronomers.
To determine the star formation history of WLM and the rate at which stars have been born over different time periods, the JWST focused on specific areas of the sky corresponding to WLM. By analyzing the colors and brightness of hundreds of thousands of individual stars within these regions, the team was able to estimate their ages. This information was then used to calculate the birth rate of stars throughout the history of the universe.
By examining the data, the researchers observed fluctuations in star formation. WLM experienced a peak in star production over a period of 3 billion years, which occurred between 2 billion and 4 billion years after the Big Bang. This burst of star formation was followed by a pause, which McQuinn attributes to specific conditions in the early universe. The high temperature of the universe at that time is believed to have heated the gas in WLM, temporarily halting star formation. After a few billion years, star formation resumed.
This research not only highlights the diverse capabilities of the JWST but also emphasizes the importance of computational power in processing and analyzing the telescope’s data. McQuinn and her team relied on the Amarel high-performance computing cluster, managed by the Rutgers Office of Advanced Research Computing, to handle the JWST’s data. The team’s efforts demonstrate various processing techniques that could benefit the wider scientific community.
The findings of this study have been published in the Astrophysical Journal, showcasing the significant contribution of the JWST to our understanding of star formation in the universe. By peering into distant galaxies like WLM, astronomers are uncovering the secrets of our cosmic origins and shedding light on how stars have evolved over billions of years. With each new discovery, we come closer to unraveling the mysteries of our vast universe.