Featured Research

from universities, journals, and other organizations

Gamma-ray Observatory Catches New Erupting Black Hole

Date:
November 28, 2006
Source:
European Space Agency
Summary:
ESA's gamma-ray observatory, Integral, has spotted a rare kind of gamma-ray outburst. The vast explosion of energy allowed astronomers to pinpoint a possible black hole in our galaxy.

Artist's representation of an X-ray nova. The compact object on the right - a neutron star or a black hole – ‘swallows’ gas from a companion star. The gas swirls in a disk around the compact object at very high velocity (close to the speed of light) and emits X-rays.
Credit: Image courtesy of European Space Agency

ESA's gamma-ray observatory, Integral, has spotted a rare kind of gamma-ray outburst. The vast explosion of energy allowed astronomers to pinpoint a possible black hole in our Galaxy.

Related Articles


The outburst was discovered on 17 September 2006 by staff at the Integral Science Data Centre (ISDC), Versoix, Switzerland. Inside the ISDC, astronomers constantly monitor the data coming down from Integral because they know the sky at gamma-ray wavelengths can be a swiftly changing place.

"The galactic centre is one of the most exciting regions for gamma ray astronomy because there are so many potential gamma-ray sources," says Roland Walter, an astronomer at the ISDC, and lead author of these results.

To reflect the importance of this region, Integral is now running a Key Programme, in which almost four weeks of its observing time is given over to the study of the galactic centre. This is allowing astronomers to understand the gamma-ray characteristics of the galactic centre and its celestial objects, better than ever before.

It was during one of the first of these observations that astronomers saw the outburst take place. An unexpected event of this kind is known as a 'target of opportunity'. At first they did not know what kind of eruption they had detected. Some gamma ray outbursts last for only a short period of time and so they immediately alerted other observatories around the world of the outburst’s position, allowing them to target the explosion, too. Fortunately, Integral has the capability to pinpoint the position of such a very bright event incredibly accurately.

In this case, the outburst continued to rise in brightness for a few days before beginning a gradual decline that lasted for weeks. The way the brightness of an outburst rises and falls is known to astronomers as a light curve. "It was only after a week that we could see the shape of the light curve and realised what a rare event we had observed," says Walter.

Comparing the shape of the light curve to others on file revealed that this was an eruption thought to come from a binary star system in which one component is a star like our Sun whereas the other is a black hole.

In these systems, the gravity of the black hole is ripping the Sun-like star to pieces. As the doomed star orbits the black hole, it lays down its gas in a disc, know as an accretion disc, surrounding the black hole.

Occasionally, this accretion disc becomes unstable and collapses onto the black hole, causing the kind of outburst that Integral witnessed. Astronomers are still not sure why the accretion disc should collapse like this but one thing is certain: when it does collapse, it releases thousands of times the energy than at other times.

Because such active star–black hole binaries are thought to be rare in the Galaxy, astronomers expect Integral to see such an outbursts only once every few years. That makes each and every one a precious resource for astronomers to study.

Thanks to the quick reactions of the astronomers at ISDC, observations were taken with satellites and observatories all around the world. ESA's XMM-Newton X-ray observatory, NASA's Chandra and Swift space telescopes, numerous ground-based telescopes captured the elusive radiation from this cataclysmic event. Now astronomers are hard at work, understanding what it all means.


Story Source:

The above story is based on materials provided by European Space Agency. Note: Materials may be edited for content and length.


Cite This Page:

European Space Agency. "Gamma-ray Observatory Catches New Erupting Black Hole." ScienceDaily. ScienceDaily, 28 November 2006. <www.sciencedaily.com/releases/2006/11/061127210901.htm>.
European Space Agency. (2006, November 28). Gamma-ray Observatory Catches New Erupting Black Hole. ScienceDaily. Retrieved November 20, 2014 from www.sciencedaily.com/releases/2006/11/061127210901.htm
European Space Agency. "Gamma-ray Observatory Catches New Erupting Black Hole." ScienceDaily. www.sciencedaily.com/releases/2006/11/061127210901.htm (accessed November 20, 2014).

Share This


More From ScienceDaily



More Space & Time News

Thursday, November 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Crowdfunded Moon Mission Offers To Store Your Digital Memory

Crowdfunded Moon Mission Offers To Store Your Digital Memory

Newsy (Nov. 19, 2014) Lunar Mission One is offering to send your digital memory (or even your DNA) to the moon to be stored for a billion years. Video provided by Newsy
Powered by NewsLook.com
Accidents Ignite Debate on US Commercial Space Travel

Accidents Ignite Debate on US Commercial Space Travel

AFP (Nov. 19, 2014) Serious accidents with two US commercial spacecraft within a week of each-other in October have re-ignited the debate over the place of private corporations in the exploration of space. Duration: 02:08 Video provided by AFP
Powered by NewsLook.com
Lunar Mission One Could Send Your Hair to The Moon

Lunar Mission One Could Send Your Hair to The Moon

Buzz60 (Nov. 19, 2014) A British-led venture called Lunar Mission One plans to send a module to the moon with keepsakes from Earth. Vanessa Freeman (@VanessaFreeTV) tells you how to get your photos and DNA onboard. Video provided by Buzz60
Powered by NewsLook.com
Why A Russian Object Is Being Called A 'Satellite Killer'

Why A Russian Object Is Being Called A 'Satellite Killer'

Newsy (Nov. 18, 2014) An unidentified Russian spacecraft is getting some attention, with some saying it could be for research while others say it could be a weapon. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins