At the Subaru Telescope in Hawaii, astronomers have uncovered a cosmic ingredient that may finally explain how the universe's brightest objects get their glow. It's called BBQSORS—a name that sounds more at home in a barbecue competition than in astrophysics, but it may prove essential to understanding the secret recipe nature uses to create quasars.
The discovery matters because quasars, those dazzlingly luminous objects that shine from the distant universe, have long puzzled astronomers. These extraordinarily bright galaxies are powered by material falling into supermassive black holes at their centers, yet how such luminous objects evolve from their earliest, hidden stages remained mysterious. Now, thanks to observations using the new ʻŌnohiʻula Pristine Field Spectrograph (PFS) aboard Subaru, researchers think they've found a crucial transitional object that bridges the gap between two cosmic populations.
BBQSORS stands for "Blackbody Quasar and Radio Source," and it was originally identified as a radio-bright quasar candidate. The real breakthrough came when astronomers at Tohoku University, Ehime University, and Ritsumeikan University analyzed its light using the ʻŌnohiʻula PFS during the instrument's filler observation program—a clever scheduling approach that allows simultaneous observations of multiple targets without slowing primary observations. What emerged from the data was surprising: BBQSORS displays features of high-speed gas swirling around a black hole like ordinary quasars, but it also shows evidence of blackbody emission from gas heated to around 10,000 degrees Kelvin, a signature unlike standard quasars.
This distinctive characteristic makes BBQSORS a bridge between two cosmic populations. On one end are "little red dots" (LRDs), mysterious objects discovered in recent years that appear shrouded in dense clouds of gas so thick they obscure the intense radiation from the black hole at the galaxy's center. On the other end sit ordinary quasars, fully revealed and blazing brightly across space. Researchers believe that BBQSORS occupies the crucial middle ground—a transitional stage where those obscuring gas clouds are being actively roasted away by the intense heat from the black hole.
"If this interpretation is correct, BBQSORS is a valuable candidate object capturing the transition from a thick-gas-enshrouded stage to an ordinary quasar," the team writes in their paper, published in the Astrophysical Journal Letters. The analogy to barbecue sauce, while playful in its name, captures something real about cosmic evolution: the process of cooking down and clearing away those dense clouds that once hid the black hole from view.
The discovery's significance lies in its potential to solve a longstanding puzzle in galaxy formation. How do black holes grow? How do the most luminous objects in the universe emerge from their early, hidden phases? BBQSORS provides observational evidence for what theorists have predicted—that there exists an evolutionary pathway from obscured, dust-choked infant quasars to the brilliant beacons we observe across billions of light-years.
With the ʻŌnohiʻula PFS now operational, astronomers expect to find more transitional objects like BBQSORS. Each discovery brings the universe's most energetic processes into sharper focus, gradually revealing the cosmic recipes that shape galaxies across time.