Astronomers catch early formation of multiple star system

AMHERST, Mass., Feb. 11 (UPI) -- A team of international astronomers recently witnessed a rarity -- the birth of stellar quadruplets. It is the first time in history scientists have caught a multi-star system in the earliest stage of formation.

The observations -- featuring before and after images that show a blur of cosmic matter becoming four distinct orbs of light -- could help scientists better understand how and why multiple star systems are formed.

"It seems like a simple question," said Jaime Pineda, a researcher with the Institute for Astronomy at ETH Zurich. "Why is our sun a single star while the nearest star to us, Alpha Centauri, happens to be a triple system? There are competing models for how multiple star systems are born, but now we know a little more than we did before."

Technically, the four spheres aren't all stars. There are three gaseous condensations, the product of a gas filament that split in three, and one very young star that is only just beginning to accrue stellar mass.

Researchers say their stellar-formation models suggest all the other three condensations will eventually form stars (in 40,000 years), but that tension between the will expel one of the four in less than one million years -- leaving a triple-star system.

Astronomers capture the rare stellar formation images using the instruments of the Very Large Array (VLA), an astronomical radio observatory in Socorro, New Mexico, and the Green Bank Telescope (GBT), the world's biggest entirely steerable radio telescope, located in West Virginia.

"This is the first time that we have been able to study these young systems in formation, and it is thanks to the combination of both GBT and VLA that we can do it," Pineda said.

"In terms of what this means for the formation of our sun," explained astrophysicist Stella Offner, "it suggests that its early conditions did not look like this forming system."

The recent observations support stellar formation models crafted by Offner, who conducts her research at the University of Massachusetts Amherst.

"Instead, the sun likely formed from something that was more spherical than filamentary," she added. "The distribution of the planets in our solar system also suggests that our sun was never part of a multiple system like this one."

The new research was published in the journal Nature.