Gas guzzler

 

This simulation shows the future behaviour of a gas cloud that has been observed approaching the black hole at the centre of the Milky Way.

Guy Fawkes' night may still be fresh in the memory, but astronomers are already jostling for ringside seats at an even more spectacular fireworks display.

Over the next few months the supermassive black hole at the centre of our galaxy will set about consuming a vast cloud of interstellar dust and gas - somewhat prosaically known as G2 - that has strayed too close to the singularity's event horizon.

It promises to be quite a show as all the material that doesn't get sucked into oblivion will be swept up, swirled around in a gigantic catherine wheel, heated, stretched, shredded and finally fired out again in a dazzling display of gravitational power. Not something astronomers get to see every day according to Dr Karen Masters from the Institute of Cosmology and Gravitation at Portsmouth University.

"The black hole at the centre of our galaxy is normally quite quiet, docile even, but as this cloud begins to fall in the material is going to get very, very hot and it's going to start emitting all sorts of radiation. We don't know exactly what's going to happen but we know it's going to be spectacular."

The galactic pyrotechnic display Sagittarius A* (as the black hole at the centre of the Milky Way is known) is about to unleash couldn't have come at a more opportune moment. NASA's latest space based X-ray telescope, NuSTAR, was only launched in June but is already offering a grandstand view of G2's death throes.

Start Quote

Black holes have had a bad rap.”

End Quote Caleb Scharf, Columbia University's Centre for Astrobiology

"We got lucky" says the mission's principal investigator, the California Institute of Technology's Fiona Harrison, "and caught an initial outburst from the black hole during our first observing campaign in July. But that's just a taste of what's to come next year, and NuSTAR will be there to catch it".

The excitement among astronomers has been fuelled by a growing appreciation for the role black holes seem play in limiting the size, and influencing the structure, of the galaxies that surround them.

Until recently Caleb Scharf, the director of Columbia University's Centre for Astrobiology, says black holes were dismissed as little more than - admittedly spectacular - cosmic plugholes.

"Black holes have had a bad rap. We've always thought of them as these dark, brooding destructive entities, but it turns out their influence is much more creative. Black holes help to regulate galaxies, acting a bit like a pressure valve that prevents star formation from running away with itself".

A powerful jet from a supermassive black hole blasts a nearby galaxy A powerful jet from a supermassive black hole blasts a nearby galaxy

In Gravity's Engines: The Other Side of Black Holes, Caleb Scharf takes this new appreciation for black holes to its logical conclusion, arguing that by dictating the large-scale structure of galaxies like the Milky Way, black holes have helped to establish the conditions necessary for life to emerge.

But it's the other, less creative, side of a black hole's personality that will be grabbing the headlines over the next few months.

"It's very exciting" Dr Scharf says "because it's the first time we've been able to predict something like this, and the first time we've had the telescopes and instruments ready to watch it in detail. We hope we'll see some of the processes at play in converting matter into energy around black holes".

The close encounter between Sagittarius A* and the G2 dust cloud is set to start early in the New Year. The latest simulations from the Lawrence Livermore National Laboratory in California suggest the massive cloud of dust and gas will have been completely consumed in less than a decade.

Quite a meal, even for a supermassive black hole.

 
Tom Feilden, Science correspondent, Today programme Article written by Tom Feilden Tom Feilden Science correspondent, Today

Building a biological model of mental illness

A team of scientists based at Cardiff University who found that a handful of genes are implicated in a wide range of debilitating neurological conditions have won £5m for further research.

Read full article

Comments

This entry is now closed for comments

Be the first to comment

Features & Analysis

BBC Future

How  crowded city life is changing us

How city life is changing us

Effect of increasingly crowded living Read more...

Programmes

  • Scene from the film TitanicHARDtalk Watch

    The film director 'appalled' at how the movies Titanic and Ironman have been re-cut for China

BBC © 2013 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.