A Maunakea observatory has discovered four mysterious objects at the center of the galaxy that defy previous classifications.
The four objects, called G Objects, emit spectra of light similar to those emitted by clouds of gas, but are very massive objects and have orbits like stars.
Astronomers at the W. M. Keck Observatory discovered the four G Objects orbiting within a few thousand astronomical units of the black hole at the center of the galaxy.
An astronomical unit is the distance between the Earth and the sun. By comparison, the Earth is more than 25,000 light years, or more than 1.5 billion astronomical units, from the same black hole.
“We don’t really know what they are,” said Randy Campbell, science operations lead at Keck Observatory. “It’s still a mystery … but you love surprises in science.
The G Objects are similar to two other objects discovered near the galactic center in 2005 and 2012. Those objects have been classified as G1 and G2, while the four discovered by Keck are classified as G3 through G6.
Campbell said one theory about the nature of the G Objects is that they were binary stars — twin stars revolving around each other — whose orbits were disrupted by the black hole and merged together over the course of millions of years.
With the discovery of more G Objects, astronomers can learn more about how galaxies and black holes evolve, Campbell said.