Existence of orbiting supermassive black holes confirmed

For the first time ever, astronomers were been able to observe and measure the orbital motion between two supermassive black holes.

Astronomers form the University of New Mexico say they’ve been able to observe and measure the orbital motion between two supermassive black holes, situated roughly 750 million light years from Earth, at the perfect distance from our planet and each other so that they can be observed.

Scientists theorized that when galaxies merged, two supermassive black holes could form and orbit each other but until now they were not able to point to a place where such a phenomenon occurred. But according to a  study published in the  Astrophysical Journal, the researchers finally found what they were looking for.

“For a long time, we’ve been looking into space to try and find a pair of these supermassive black holes orbiting as a result of two galaxies merging,” said Greg Taylor, UNM Professor and co-author of the study. “Even though we’ve theorized that this should be happening, nobody had ever seen it until now.”

Using the Very Long Baseline Array, the astronomers were able to observe the radio signals emitted by several supermassive black holes. And over time, they were also calculated their trajectory, showing that they orbited each other.

“When Dr. Taylor gave me this data I was at the very beginning of learning how to image and understand it,” said UNM Department of Physics & Astronomy graduate student Karishma Bansal, first author of the paper. “And, as I learned there was data going back to 2003, we plotted it and determined they are orbiting one another. It’s very exciting.”

The two black holes are unbelievable in size. The astronomers calculated that they have a combined mass of 15 billion times that of our sun, or 15 billion solar masses an they have an orbital period of around 24,000 years, so while the team has been observing them for over a decade, they’ve yet to see even the slightest curvature in their orbit.

“If you imagine a snail on the recently-discovered Earth-like planet orbiting Proxima Centauri – 4.243 light years away – moving at 1 cm a second, that’s the angular motion we’re resolving here,” said Roger W. Romani, professor of physics at Stanford University and member of the research team.

And while the discovery itself and the technology behind it are both extremely important, the scientists say that they also have the potential of teaching us more about the universe and about how galaxies form. Continuing to observe the supermassive black holes could also offer up new insights into the future of our own galaxy.

Andromeda also has a supermassive black hole at its center and it’s on the path of colliding with our own Milky Way.

“Supermassive black holes have a lot of influence on the stars around them and the growth and evolution of the galaxy,” explained Taylor. “So, understanding more about them and what happens when they merge with one another could be important for our understanding for the universe.”

The scientists will continue their observations in order to confirm the orbit and hopefully their work will inspire other astronomers.