On a desolate, rocky mountaintop in the middle of the Pacific Ocean, one of the world’s most advanced ground-based telescopes and a team of University researchers seek to shed light on some of the universe’s greatest astronomical phenomena.

A study published Thursday in the journal Nature challenged the current understanding of light emissions from black holes, based on the observations of a collaborative global team of researchers at the Gemini Observatory in Hawaii.

It was previously believed that light emission, or luminosity, from black holes reaches a threshold called the Eddington limit, at which no more light can be emitted due to the physics of the black hole. Recent research, led by Astronomy Prof. Joel Bregman, used various properties of the black hole and neighboring stars to suggest this limit may be exceeded in some cases.

“I think this is a first salvo in this field,” Bregman said. “It shows that you can get the data together to figure out the orbital properties.”

The findings at the Gemini Observatory served as the final step in a series of global studies conducted with the hope of determining the mass of a single black hole in the Pinwheel Galaxy, located approximately 21 million light-years from earth. Once the mass was determined, the scientists realized light emissions from the region were much higher than they should appear under the Eddington limit.

“This is a very tidy result but it’s not all-encompassing,” Bregman said. “But maybe not all ultra-luminous sources are the same. What you want to do now is do it for other systems.”

Black holes are regions of space so dense that even light cannot escape the pull of their gravity beyond a boundary called the event horizon. When they are observed from earth-based telescopes, their center appears black.

Contrary to their namesake, black holes are actually some of the brightest objects in the universe. As matter is pulled toward the event horizon, it gains speed and collides with other similar objects. This creates friction as objects closer to the horizon move faster than objects farther away.

“That friction gets turned into heat which gets turned into light, which is why black holes are so bright,” Bregman said.

Larger black holes, known as intermediate or supermassive, can range from a few hundred to a billion times larger than the sun. The black hole observed in the study, designated as ULX-1, is known as a stellar mass black hole. Although it is much smaller than other types, it is still many times larger than the sun.

Given the emission level from ULX-1, scientists knew it was either a stellar mass black hole emitting too much light or an intermediate black hole emitting a small portion of its potential. Using the Gemini telescope, the researchers were able to determine the velocity, period and mass of surrounding stars, allowing them to calculate the mass of the black hole.

“It’s a crazy field in that every time you get 10 pieces of information, five say it’s a stellar mass black hole and five say it’s an intermediate black hole,” Bregman said.

At such vast distances, the researchers were observing primarily x-ray light, which is not visible to the naked eye. The Gemini telescope, as well as several others used on the project, was equipped with instruments capable of detecting the various forms of light emitted from the region.

“They’re very faint, so it’s very hard to do,” Bregman said. “The techniques that you would use in the Milky Way just don’t work.”

Of all scientific phenomena, Bregman said the people he interacts with are intrinsically and rightfully drawn to black holes. The observatories used in the study are not only major research centers, but also tourist attractions for individuals wishing to explore the universe.

“They are the most exotic objects in the universe,” he said. “They are a place where the actual fabric of space-time breaks down. You might care about anything because either it’s going to make you a better piece of toast in the morning or it’s just really interesting — black holes are just really interesting.”

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