For the first time, astronomers have spotted a system with more than one star in the very earliest stages of its formation. Their findings, published Wednesday in the journal Nature, help support one of several proposed mechanisms by which scientists think these multistar systems might form.
For the first time, scientists have caught what they think is a multistar system on the brink of forming. Right now, we have very little sense of what makes one solar system have one star while another has two or three. Catching one in the process of forming will help answer those questions.
Eight hundred light years away, a young protostar shares a cloud of gas with three cold, dense gas balls — each dense enough to form a star of its own. Based on the system's conditions, the researchers believe that the dense balls will collapse into stars of their own in just 40,000 years or so.
"It could form a quadruple system," said first author Jaime Pineda, now working at the Max Planck Institute for Extraterrestrial Physics. Star systems with more than three stars quickly grow unstable, he said, so a four-star system isn't likely to last for very long, "but at the very least it's going to be a binary."
The new system is especially interesting because of its spacing, Pineda said.
"These potential stars aren't very close to each other. They're separated by several thousand times the distance between the Sun and the Earth," he said. It's generally assumed that binary systems have to form close together and then can later spread out across large distances. "But it seems that actually you don't need to do all that," Pineda said. "You can form them at very large distances from each other from the very beginning."
Forty thousand years may be an extremely short time on a cosmic scale, but it's too long for us to hope to watch the birth in action. Pineda is still eager to get a closer look. This system had been observed before, he said, but only the high-resolution views of the most advanced modern telescopes gave them the images they needed to detect the three would-be stars.
"We'd like to observe it at an even higher resolution," he said. And then, of course, there's the task of turning those high-powered telescopes elsewhere in the hope of finding similar new formations.
"We'll be targeting more regions that show dense and cold gas like this one," Pineda said. "We have to find out if this method of multiple star formation is common, or if it's really just an oddball."