Astronomers have made a groundbreaking discovery using NASA’s Atacama Large Millimeter/submillimeter Array (ALMA) and James Webb Space Telescope (JWST).
They observed twoin disks and parallel jets erupting from a few young stars in the star system WL20, located more than 400 light-years away in the rho Ophiuchi molecular cloud complex. This unexpected finding provides new insights into the early stages of star formation and the dynamical 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 close together.
Each of these stars was surrounded by a disk, and each disk emitted jets parallel to the other. Dr. Barsony noted: “What we discovered was absolutely wild. We’ve known about galaxy 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 exciting because of its location WL20 in a well-studied region of space. The ability to find such a unique and dynamic system in a known area highlights the importance of using multiple observation techniques. “Using MIRI and ALMA together, we actually saw that this one star was two stars right next to each other,” Barsony explains. “Each of these stars was surrounded by a disk, and each disk emitted jets parallel to the other.”
Combining multiple wavelengths
The combination of ALMA and JWST was crucial to this discovery. ALMA, which observes in the radio wavelengths, detected the disks, while JWST’s MIRI, which operates in the infrared spectrum, identified the jets. This multi-wavelength approach allowed astronomers to discover details hidden from previous observations. Dr. Barsony emphasized the importance of MIRI in detecting the jets, noting: “So if it weren’t for MIRI, we wouldn’t even know these jets existed, which is amazing.”
The data collected by ALMA and JWST was analyzed in detail to reveal the composition of the disks and the chemical composition of the jets. Valentin JM Le Gouellec van NASA ARC collected and reduced ALMA archival data, while Lukasz Tychoniec of Leiden Observatory provided high-resolution images of the disks, showing their enormous size, about 100 times the distance between Earth and the Sun. Martijn L. van Gelder contributed to the processing of the data collected by MIRI, which revealed the chemical composition of the jets.
Insights into star formation
ALMA’s high-resolution data revealed the structure of the disks, which are about 100 times the distance between 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 explains: ‘Someone looking at this ALMA data and not knowing there were two jets would think, oh, it’s a big disk on the edge with a central hole, instead of two disks on the edge and two jets. That’s quite remarkable. “
The findings from this study shed light on the complex processes that determine the birth and evolution of stars in multiple star systems. By observing the twin disks and jets in WL20, astronomers can gain a better understanding of how these systems evolve and interact with each other over time. The ability to observe these phenomena in such detail opens new avenues for research into the mechanisms of star formation.
Future research and implications
The researchers plan to use ALMAs future enhanced capabilities, such as the Wideband Sensitivity Upgrade, to continue exploring the mysteries surrounding the birth of stars and planetary systems. These advances will further advance our understanding of star formation and the dynamical 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 an important 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. “Much of the research on binary protostars focuses on a few nearby star-forming regions. I had gotten some private observation time at JWST and I chose to split it into a few small projects,” he said. ‘For one project I decided to study double stars in the star-forming region of Perseus. However, I had been studying WL20 for almost thirty years, which is in the rho Ophiuchus region, almost on the other side of the sky, and I thought, ‘why not sneak it in? I’ll never get another chance, even if it doesn’t quite fit in with the others.’ We had a very fortunate accident with what we found, and the results are amazing.”
By combining data across multiple wavelengths ALMA and JWSTThese 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, expanding our understanding of the universe and the birth of stars.
