The astronomers, including Michele Fumagalli from the Carnegie Institution for Science in Washington, made the identification by combing observations from the European Southern Observatory at La Silla, Chile, and from the Calar Alto Observatory in Spain.
Quasars are extremely bright and powerful sources of energy that sit in the center of a galaxy, surrounding a black hole. Systems with multiple quasars are believed to be the product of galaxies colliding, the researchers said.
The light from the triple quasar system called QQQ J1519+0627 has traveled 9 billion light-years to reach Earth, which means the light started its journey when the universe was only a third of its current age, they said.
Two members of the triplet are closer to each other than the third, the researchers said, suggesting this quasar system is part of some larger structure that is still undergoing formation.
"Honing our observational and modeling skills and finding this rare phenomenon will help us understand how cosmic structures assemble in our universe and the basic processes by which massive galaxies form," Fumagalli said.