A young star in a constellation shrouded in a dense cloud of gas and dust Ophiuchus which astronomers have been studying for decades have been found to be a duo. It would also appear that both members of the pair are surrounded by a disk of material in which the planets may have just begun to coalesce.
Twins, of which there are about 400 light years of Earth in the WL 20 group are less than a million years old and appear to have displaced the bulging orange clouds in which they formed, indicating that their birth is nearing its end. This means astronomers can observe stars as they transition into adulthood.
For decades, telescope observations have shown the WL 20 group to lie in a massive molecular cloud called Rho Ophiuchi, hosts three stars laid out as the points of a triangle. Although born in the same pocket of gas and dust, two stars they were about two million years old. The third star – the faintest of the group perched on the southern tip of the triangle – appeared to be less than a million years old.
“How could that be?” Mary Barsony, the independent astronomer who led the discovery, said Wednesday (June 12) while presenting the discovery at the 244th meeting of the American Astronomical Society in Wisconsin. Many astronomers, including Barsony, have studied triplets in WL 20 and their cosmic home Rho Ophiuchi for decades. “We thought we knew it pretty well,” she said declaration provided by NASA.
Related: ‘Supernova discovery machine’ James Webb Space Telescope has found the most distant star explosion on record
Nevertheless, when The James Webb Space Telescope observed the region, its powerful MIRI (Mid-Infrared Instrument) found a third star, called WL 20S, actually a pair of twins itself—each member of the pair with matching jets streaming into space from its north and south poles. Further observations by ALMA (short for Atacama Large Millimeter/submillimeter Array), a large network of 60 radio antennas in Chile that act as a giant telescope, revealed that each of the binaries was also surrounded by a disk of gas and dust. If our Sun were to be replaced by one of the binary stars, its disk would overlap Saturnin orbit, Barsony said.
“We were absolutely stunned when we first saw these images,” she told reporters during a news conference. Without MIRI, astronomers would not know about the binary or the jets, she added. “It’s like having brand new eyes.
Astronomers do not fully understand how multiple star systems like the one containing the four stars in WL 20 form. So future observations of the quartet could shed more light on the underlying processes.
“It’s amazing that this region still has so much to teach us about the life cycle of stars,” said study co-author Mike Ressler, who is a project scientist for MIRI at NASA. Current drive laboratory and has been studying the WL 20 group for almost 30 years.
When Ressler got some observing time with JWST, he decided to point the telescope towards WL 20, which was in the opposite part of the sky to his other targets.
“I thought, ‘Why not smuggle it in? I’ll never get another chance, even though it doesn’t quite fit the others,’ Ressler said. “We had a very lucky accident with what we found; the results are astounding.”