For decades, astronomers have been captivated by the enigmatic behavior of Markarian 1018, a galaxy located an astonishing 555 million light-years away.
Once known for its fluctuating brightness, this cosmic beacon has suddenly gone dark—and scientists believe something extraordinary is happening.
But what could cause an entire galaxy’s glow to fade so dramatically?
A supermassive black hole losing its fuel might sound like a straightforward explanation, but new evidence suggests something far more intriguing: another black hole might be stealing its cosmic dinner.
If true, this would provide an unprecedented glimpse into one of the universe’s most elusive and chaotic battles—a cosmic struggle between two supermassive black holes.
A Galaxy That Refuses to Stay the Same
Markarian 1018 is no ordinary galaxy.
It belongs to a rare class of active galaxies that undergo dramatic shifts in brightness, and its past behavior has kept astronomers on their toes for nearly 50 years.
- 1970s – When first observed, the galaxy was dim, seemingly quiet and unremarkable.
- 1975-1980 – Within just five years, Markarian 1018 had transformed into a shining beacon, classified as a Type I Seyfert galaxy—a category of bright active galaxies powered by massive black holes.
- 2016 – The galaxy’s light nearly vanished, leaving scientists baffled.
To understand what happened, a team of international researchers turned to the European Southern Observatory’s Very Large Telescope (ESO VLT) for answers.
What they found challenged everything they thought they knew.
What’s Really Happening? A Cosmic Power Struggle Unfolds
The prevailing theory has long been that a supermassive black hole shines brightly because of accretion—the process of swallowing matter, heating it to extreme temperatures, and emitting powerful radiation.
If the black hole at the center of Markarian 1018 suddenly dimmed, the logical conclusion would be that it simply ran out of fuel.
But the evidence doesn’t quite add up.
“We were stunned to see such a rare and dramatic change in Markarian 1018,” says lead researcher Rebecca McElroy from the University of Sydney.
“Something slightly more dramatic has gone on.”
Instead of just running out of matter to devour, researchers believe the black hole may be losing a cosmic tug-of-war against a second black hole.
Stealing the Spotlight?
Scientists propose that Markarian 1018 has been undergoing a slow-motion galactic collision with another galaxy.
And this isn’t just any galaxy—it’s likely another active galaxy, meaning it also harbors a supermassive black hole at its core.
When galaxies collide, their respective black holes don’t just peacefully coexist.
Instead, they begin a long, gravitational dance, pulling at each other and affecting the way material flows into them.
The implications?
- Two supermassive black holes battling for dominance in the same system.
- One black hole disrupting the gas flow into the other, effectively “starving” it.
- A potential future merger, which could create an even larger, ultra-powerful black hole.
As McElroy puts it:
“Most galaxies have supermassive black holes, and if you throw two galaxies at each other, there are going to be two black holes that will eventually sink to the center.”
A Rare Opportunity
If these theories prove correct, Markarian 1018 could offer astronomers a rare front-row seat to an event that takes millions of years to unfold.
Supermassive black hole mergers are among the most powerful cosmic events in existence, and yet, they remain largely theoretical.
Observing one in action would:
- Refine our understanding of how galaxies evolve and merge.
- Confirm how black holes interact and influence each other’s feeding habits.
- Provide new data for gravitational wave studies, as merging black holes produce ripples in spacetime detectable by observatories like LIGO and Virgo.
What Comes Next?
Scientists aren’t just watching from the sidelines—they are actively investigating the mystery.
The team is leveraging NASA’s Hubble Space Telescope, the Chandra X-ray Observatory, and other powerful instruments to gather more data.
“We have been able to rule out a couple of scenarios, but data are still flooding in,” says McElroy.
“The team is really keen on finding out more about the physics that drive the behavior of this unusual galaxy.”
A Cosmic Drama in Progress
Markarian 1018 is more than just a flickering light in the cosmos—it’s a front-row seat to one of the universe’s most compelling and mysterious processes.
If the theory of two battling black holes holds, we might be witnessing the slow-motion merger of two giants—an event that will shape this galaxy for eons to come.
For now, the battle rages on, unseen but unmistakable. As new data pours in, one thing is clear: Markarian 1018 is a cosmic drama worth watching.
