Scientists find a galaxy that defies conventional wisdom
Scientists have spotted a defiant galaxy.
Located nearly 1 billion light-years from Earth, the galaxy 2MASX J23453268−0449256 is a spiral, like our home the Milky Way. Yet it does something galactic researchers only thought possible in much more massive elliptical galaxies, which form through mergers of galaxies: It hosts an enormous supermassive black hole that emits powerful jets of energy into space — the type that would wreak havoc and destabilize such a spiral galaxy.
"This discovery upends conventional wisdom, as such powerful jets are almost exclusively found in elliptical galaxies, not spirals," Suraj Dhiwar, a researcher at the Inter-University Centre for Astronomy and Astrophysics in India who coauthored the new study, told Mashable.
The research was published in the peer-reviewed journal Monthly Notices of the Royal Astronomical Society.
Spiral galaxies are often considered too delicate to support the kind of extreme black hole activity seen in this galactic system, Joydeep Bagchi, an astrophysicist at Christ University in India who led the research, told Mashable. But this galaxy maintains its well-ordered spiral structure in the face of extreme blasts of energized particles and radiation from a black hole billions of times the mass of the sun, as you can see in the Hubble Space Telescope imagery above and below.
"This discovery upends conventional wisdom."
Black holes themselves — so gravitationally powerful not even light can escape their grasp — produce no radiation or light. But galactic material can rapidly spin around black holes, forming a vibrant "accretion disk" that radiates light. And sometimes material falling into a black hole can be rerouted into two giant jets, firing in opposite directions out into the universe.
The cosmic quandary of the expansive spiral galaxy 2MASX J23453268−0449256 calls for more telescopic investigation, the researchers emphasize. "It forces us to rethink how galaxies evolve, and how supermassive black holes grow in them and shape their environments," Dhiwar explained.
So far, observations gathered by the Hubble Space Telescope, the Giant Metrewave Radio Telescope, and the Atacama Large Millimeter Array reveal that the galaxy doesn't only have an orderly, tranquil spiral appearance. It also maintains a bright nuclear bar-shaped mass of stars near its core (as many spiral galaxies do) and an undisturbed outer stellar ring — home to some vigorous star formation.
The unusual circumstance of galaxy 2MASX J23453268−0449256 also has relevance to our galaxy. While the central supermassive black hole in the Milky Way, called Sagittarius A*, is much smaller and currently dormant, it could (one far-off day) awake. A mighty gas cloud or small dwarf galaxy could accrete around the black hole, providing the fuel needed for powerful jets of radiation to blast through our galaxy. These rapidly moving particles could pose a danger to planets.
"If such jets were to form and be directed toward our solar system, they could potentially strip away planetary atmospheres, increase radiation exposure, and even trigger a mass extinction event on Earth," Bagchi said.
Life on Earth has indeed thrived over eons, and eventually bounced back following mass extinctions. But might another, stoked by our massive black hole, be in the cards? Grasping how such active black holes behave in spiral galaxies can help us not just grasp the fate of our galaxy, but others.
"Ultimately, this study brings us one step closer to unraveling the mysteries of the cosmos, reminding us that the universe still holds surprises beyond our imagination," Dhiwar said.