Feeds

Super-fast super-massive black hole spins at nearly light-speed

NuStar boffins peek through the clouds at NGC 1365

Application security programs and practises

NuStar – the X-ray telescope launched by NASA last year – is turning in its first science with measurements revealing that the outer edges of the NGC 1365 black hole are spinning at 84 percent of light-speed or more.

The supermassive black hole in the NGC 1365 galaxy has a mass more than two million times that of the sun, but it’s the measurement of its accretion disk’s spin rate that’s impressive here.

There was already a suspicion, gleaned through observations made by the European XMM-Newton space telescope, that the black hole was something special. However, as the NuStar announcement states, estimates of the object’s spin rate may have been distorted by the huge amount of dust in the galaxy.

As matter in the accretion disk of a black hole falls in, it gives off X-rays; and the more massive the black hole, the smaller the accretion disk. This, in turn, means the X-rays are emitted from a spot closer to the gravity well, and therefore suffer more distortion.

Looking at NGC 1365, the astronomers focussed on X-rays emitted by iron in the accretion disk, combining observations from NuStar with others from Europe’s XMM-Newton space telescope.

Differing views of NGC 1365

This ESA image of NGC 1365 shows how much deeper NuStar is able to "zoom in" on the black hole

“With help from XMM-Newton, NuSTAR was able to see a broader range of X-ray energies and penetrate deeper into the region around the black hole. The new data demonstrate that X-rays are not being warped by the clouds, but by the tremendous gravity of the black hole,” the statement says.

With these more accurate measurements of the emitted X-rays, the astronomers were able to measure the Doppler effect caused by the black-hole’s rotation, revealing its relativistic speed. If The Register understands the detail in the astronomers’ paper in Nature (abstract here) correctly, the upper limit for the spin rate could be as much as 97 percent of light-speed.

As Phil Plait discusses here, there are a couple of possible explanations for the unbelievable speed: the black hole may simply have swallowed lots of matter that arrived at the right angle to add to its angular momentum; or a galactic collision could have turned two black holes into one with a huge boost to the spin on its accretion disk.

NASA has a set of visuals and videos here. ®

Build a business case: developing custom apps

More from The Register

next story
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
BEST BATTERY EVER: All lithium, all the time, plus a dash of carbon nano-stuff
We have found the Holy Grail (of batteries) - boffins
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Forty-five years ago: FOOTPRINTS FOUND ON MOON
NASA won't be back any time soon, sadly
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.