Possibly the largest black hole in the universe has been discovered

They’re huge. They’re invisible. They collapse space and time into infinity*.

But black holes could prove to be the centre of, well, everything.

Astronomers* have discovered the most monstrous supermassive black hole ever. At 36 billion times more mass than our sun, it’s so big it’s pushing back the boundaries of possibility. They’ve even had to rename it “ultra” massive to describe its scale.

But size is just the start of the story.

It’s also about the stars of the giant elliptical* galaxy Messier 87 surrounding the black hole: their speed, number and age.

Put them together and you get a remarkable puzzle. Black holes devour stars and interstellar gas, which causes them to grow. But they also turn into quasars*, excreting* blasts of raw energy back out into space, sparking another cycle of star formation.

So which came first? Is this black hole the chicken or the egg?

“With this latest find, we have another clue to the greatest chicken-and-egg puzzle in all the universe,” said astrophysicist* Dr Ethan Siegel. “ With a little luck, we’ll have an even better picture of how our universe actually grew up in just a few years.”

GARGANTUAN DISCOVERY
Messier 87 is one of the largest galaxies ever found. It is located some five billion light-years away, meaning the light reaching us was emitted at a time when the universe was only two-thirds its current age.

It was already a fossil galaxy by that time and had devoured all of its surrounding smaller galaxies, star clouds and gas.

“It is likely that all of the supermassive black holes that were originally in the companion galaxies have also now merged to form the ultra-massive black hole that we have detected,” said University of Portsmouth researcher Professor Thomas Collett.

It’s called the Cosmic Horseshoe because of the effect it has on the space around it.

Its gravity is so powerful that it has bent the light of stars in a distant blue galaxy behind it into a near-perfect circle.

It’s an effect first predicted by Einstein more than a century ago. Hundreds of examples have since been found.

Now, a new study published in the monthly notices of the Royal Astronomical Society has calculated the black hole at Messier 87’s core as being 10,000 times more massive than that at the centre of our own galaxy.

“This is amongst the top 10 most massive black holes ever discovered, and quite possibly the most massive,” said Professor Collett.

But the power of its magnification has given astronomers a rare opportunity to observe such a distant and ancient structure in detail.

“We detected the effect of the black hole in two ways – it is altering the path that light takes as it travels past the black hole, and it is causing the stars in the inner regions of its host galaxy to move extremely quickly (almost 400 km/s).

“By combining these two measurements, we can be completely confident that the black hole is real.”

MASSIVE IMPLICATIONS
“So we’re seeing the end state of galaxy formation and the end state of black hole formation,” said Professor Collett.

But the Cosmic Horseshoe black hole should not exist. It’s too big for its age.

And astronomers are finding increasing numbers of similar over-massive black holes in the earliest stages of the universe.

All of which suggests that Messier 87 could be evidence of a different creation story.

“When you looked at galaxies today, you’d find a correlation between how much mass is in the form of stars within the galaxy and how heavy the supermassive black hole is,” said Dr Siegel.

That ratio is about 1000 to 1.

“Then, when you looked at galaxies at earlier times, you’d expect that the correlation would remain the same (with the same ratio) for some time, before ‘tilting’ at early times to favour more stellar mass and lower supermassive black hole mass,” he said.

That’s because the young black holes wouldn’t have had much time to gorge themselves on their surrounding stars.

But given the size and age of the Messier 87 galaxy, its ultra-massive black hole is too big. It appears to have eaten more than it could have.

“When compared with galaxies found more locally, the team of scientists found that … its black hole is much more massive than its central stellar velocity dispersion* would indicate,” Dr Siegel said. “Additionally, the black hole appears to be over-massive compared to the total stellar mass of the galaxy.”

Messier 87 is not the first galaxy containing a supermassive black hole that presents the possibility of a different order at the origin of the universe. But it is the biggest and the oldest.

“What we find, remarkably, for the earliest galaxies of all … going all the way back to just (approximately) 420 million years after the Big Bang … is that nearly all of the ones with black holes display over-massive black holes.”

They appear to have star-to-black hole mass ratios of 100-to-1 or 10-to-1 instead of the currently observed 1000-to-1.

“In other words, early on, ‘over-massive’ black holes are actually typical,” Dr Siegel said. “This is interesting and highly suggestive of the notion that black holes, and not stars, came first”.

THE FUTURE OF SPACE TOURISM

POLL

GLOSSARY

• infinity: state of being without end or limit
• astronomers: scientists who study the stars, planets, and other natural objects in space
• elliptical: having an oval shape
• quasar: the centre of a galaxy – being a group of stars – that is very far away, producing large amounts of energy
• astrophysicist: scientist who studies space, stars, planets, and the universe
• stellar velocity dispersion: measures the random motion of stars in a galaxy, closely related to the dark matter halo

EXTRA READING

Big planet found orbiting tiny star

Are we living in a giant black hole?

New view of Milky Way monster

QUICK QUIZ

1. The super-massive black hole is at the centre of which galaxy?
2. The black hole’s mass is how many times that of our sun?
3. How far away is the black hole’s galaxy in light-years?
4. What is the name given to the black hole and why?
5. What is the correlation Dr Siegel said you would find when looking at galaxies today?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Black holes and stars
After reading the Kids News article on the discovery of this new “monstrous super massive black hole”, record what the evidence is that supports the theory that black holes came before stars.

You may like to draw your answer as a diagram to help you explain.

Time: allow 15 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking

2. Extension
After reading this article, write down any questions or wonderings you have.

Join a partner and see if they can answer your questions and if you can answer any of theirs.

Time: allow 10 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking

VCOP ACTIVITY
Read this!
A headline on an article – or a title on your text – should capture the attention of the audience, telling them to read this now. So choosing the perfect words for a headline or title is very important.

Create three new headlines for the events that took place in this article. Remember, what you write and how you write it will set the pace for the whole text, so make sure it matches.

Read out your headlines to a partner and discuss what the article will be about based on the headline you created. Discuss the tone and mood you set in just your few, short words. Does it do the article justice? Will it capture the audience’s attention the way you hoped? Would you want to read more?

Consider how a headline or title is similar to using short, sharp sentences throughout your text. They can be just as important as complex ones. Go through the last text you wrote and highlight any short, sharp sentences that capture the audience.