Astronomers have made a groundbreaking discovery using the Atacama Large Millimeter/submillimeter Array (ALMA) and NASA’s James Webb Space Telescope (JWST).
They observed twin disks and parallel jets erupting from a pair of young stars in the star system WL20, located over 400 light-years away in the rho Ophiuchi molecular cloud complex. This unexpected finding offers new insights into the early stages of star formation and the dynamic processes involved.
A Surprising Discovery
The discovery, led by astronomer Dr. Mary Barsony, revealed unexpected findings about the WL20 star system. Initially, one star in the system appeared much younger than the others. However, detailed observations using ALMA and JWST‘s Mid-Infrared Instrument (MIRI) showed that this “one” star was actually two stars situated close together.
Each of these stars was surrounded by a disk, and each disk was emitting jets parallel to the other. Dr. Barsony remarked, “What we discovered was absolutely wild. We’ve known about star system WL20 for a long time. But what caught our attention is that one of the stars in the system appeared much younger than the rest.”
This discovery was particularly thrilling because of the location of WL20 in a well-studied region of space. The ability to find such a unique and dynamic system in a familiar area emphasizes the importance of using multiple observational techniques. “Using MIRI and ALMA together, we actually saw that this one star was two stars right next to each other,” Barsony explained. “Each of these stars was surrounded by a disk, and each disk was emitting jets parallel to the other.”
Combining Multiple Wavelengths
The combination of ALMA and JWST was crucial for this discovery. ALMA, which observes in the radio wavelengths, detected the disks, while JWST’s MIRI, operating in the infrared spectrum, identified the jets. This multi-wavelength approach allowed astronomers to uncover details hidden from previous observations. Dr. Barsony highlighted the significance of MIRI in detecting the jets, noting, “So if it weren’t for MIRI, we wouldn’t even know that these jets existed, which is amazing.”
The data collected by ALMA and JWST was analyzed in detail to reveal the disks’ composition and the chemical makeup of the jets. Valentin J.M. Le Gouellec of NASA-ARC retrieved and reduced ALMA archival data, while Lukasz Tychoniec of Leiden Observatory provided high-resolution images of the disks, revealing their massive size, approximately 100 times the distance between the Earth and the Sun. Martijn L. van Gelder contributed to processing the data collected by MIRI, unveiling the jets’ chemical composition.
Insights Into Star Formation
The high-resolution data from ALMA revealed the structure of the disks, which are approximately 100 times the distance between the Earth and the Sun. The detailed analysis of these disks and jets provides new insights into the complex processes involved in the formation of multiple star systems. Dr. Barsony explained, “Someone looking at this ALMA data not knowing there were twin jets would think, oh, it’s a large edge-on disk with a central hole, instead of two edge-on disks and two jets. That’s pretty remarkable.”
The findings from this study shed light on the intricate processes that govern the birth and evolution of stars in multiple star systems. By observing the twin disks and jets in WL20, astronomers gain a deeper understanding of how these systems develop and interact over time. The ability to observe these phenomena in such detail opens up new avenues for research into the mechanisms of star formation.
Future Research And Implications
The researchers plan to utilize ALMA’s future upgraded capabilities, such as the Wideband Sensitivity Upgrade, to continue investigating the mysteries surrounding the birth of stars and planetary systems. These advancements will further enhance our understanding of star formation and the dynamic interactions within multiple star systems.
Dr. Barsony and her team presented their findings at the 244th Meeting of the American Astronomical Society in Madison, Wisconsin, marking a significant milestone in the study of young stars and their developmental processes.
Dr. Barsony’s colleague, JPL scientist Michael Ressler, reflected on the serendipitous nature of the discovery. “A lot of the research about binary protostars focuses on a few nearby star-forming regions. I had been awarded some observing time of my own with JWST, and I chose to split it into a few small projects,” he said. “For one project, I decided to study binaries in the Perseus star-forming region. However, I had been studying WL20, which is in the rho Ophiuchus region in nearly the opposite part of the sky, for nearly 30 years, and I thought, ‘why not sneak it in? I’m never going to get another chance, even if it doesn’t quite fit with the others.’ We had a very fortunate accident with what we found, and the results are stunning.”
By combining multi-wavelength data from ALMA and JWST, these new findings shed light on the complex processes involved in the formation of multiple star systems. The continued exploration and observation of star systems like WL20 will undoubtedly lead to further discoveries, enhancing our comprehension of the universe and the birth of stars.
