Rare Triple Quasar Found 9 Billion Light Years Away
A rare triple quasar located 9 billion light years away has been discovered by an international team of astronomers, according to a report released Tuesday in the journal Monthly Notices of the Royal Astronomical Society.
The modern theory is that they are the cores of distant galaxies very far away. The light from the quasars is highly redshifted, allowing scientists to calculate how much the universe has expanded since the light started traveling toward us and therefore how much time has passed during their travels toward earth.
One quasar, 3C 273, is "only" a bit more than 2.4 billion years away and can be seen with amateur equipment, but most quasars can’t be seen without professional telescopes. The triple quasar, at 9 billion light years away, presented a challenge.
When two or more quasars are found together, it could be evidence that they’re colliding to form a future cluster. In this case, two of the quasars seem to be already melting together, while the more distant third is perhaps just beginning to respond to the pull of gravity created by the other two.