Scientists identify formation of three planetary systems around this binary star

Scientists have identified the formation of three planetary systems around a binary star system called SVS 13.

Located 980 light-years away, the binary star system and the complex structures of dust around it are shedding light on how planetary systems are born in these fascinating environments.

The research has been accepted by The Astrophysical Journal and is available on preprint server arXiv.

Also read | Scientists confirm several geomagnetic storms are going to hit Earth this week

Bringing together three decades of study, an international group of scientists have observed a pair of stars orbiting each other, to reveal that these stars are surrounded by disks of gas and dust.

Using the Very Large Array (VLA) and the Atacama Large Millimeter/Submillimeter Array (ALMA), the scientific group has studied the binary star SVS 13, still in its embryonic phase. This work has provided the best description available so far on a binary system in formation.

Models of planet formation suggest that planets form by the slow aggregation of ice and dust particles in protoplanetary disks around forming stars. Usually these models consider only single stars, such as the Sun. 

However, most stars form binary systems, in which two stars rotate around a common centre.  Very little is yet known about how planets are born around these important twin star systems, in which the gravitational interaction between the two stars plays an essential role. 

Also see | Why has space business has become the final profitable frontier?

"Our results have revealed that each star has a disk of gas and dust around it and that, in addition, a larger disk is forming around both stars," says Ana Karla Díaz-Rodríguez, a researcher at the IAA-CSIC and the UK ALMA Regional Centre (UK-ARC) at The University of Manchester, who leads the work.

“This outer disk shows a spiral structure that is feeding matter into the individual disks, and in all of them planetary systems could form in the future. This is clear evidence for the presence of disks around both stars and the existence of a common disk in a binary system.”

The binary system SVS 13 consists of two stellar embryos with a total mass similar to that of the Sun. The two stars in the system are very close to each other, with a distance of only about ninety times that between the Earth and the Sun.

Also read | NASA is cracking open a 50-year-old vacuum-sealed tube of lunar gas and soil

The work has made it possible to study the composition of gas, dust and ionised matter in the system. In addition, nearly thirty different molecules have been identified around both protostars, including thirteen complex organic molecules precursors of life (seven of them detected for the first time in this system). 

"This means that when planets begin to form around these two suns, the building blocks of life will be there," says Ana Karla Díaz-Rodríguez.

The scientific team has used the observations of SVS 13 obtained by the VLA over thirty years, together with new data from ALMA, and has followed the motion of both stars over this period, which has allowed their orbit to be traced, as well as the geometry and orientation of the system, along with many fundamental parameters, such as the mass of the protostars, the mass of the disks, and their temperature. 

Gary Fuller of The University of Manchester, a collaborator on the project, says: “This work shows how careful, systematic studies of young stars can provide a remarkably detailed view of their structure and properties.“

(With inputs from agencies)