Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breakthrough in puzzle of giant explosions in space

15.12.2005


Astronomers at the University of Hertfordshire have helped to solve one of the longest standing puzzles in astrophysics— the nature of the enormous explosions known as short-duration gamma ray bursts (GRBs).



In a paper to be published in Nature tomorrow (15th December), they will reveal that around 15% of short-duration bursts originate from galaxies within 300 million light years of the Milky Way – more than 10 times closer than previously thought.

Dr Nial Tanvir who is leading the Hertfordshire team commented: “GRBs are difficult to observe because they last such a short time, and the signature flash of gamma rays can only be observed by specially-designed satellites.”


He claims that this was one of the reasons that the nature of GRBs remained completely enigmatic until 1997, when it was found that at least one variety— the so-called `long-duration’ bursts, which last for more than two seconds — arise in very remote galaxies, billions of light years distant, and therefore must be the most violent explosions known.

However, the second variety of GRBs — the short-duration bursts (those lasting less than two seconds) — remained mysterious until earlier this year when a few short bursts were pin-pointed sufficiently well to track down their host galaxies. From looking at the kinds of galaxies the bursts were found in, and the way their light faded away, astronomers have concluded that these events were most likely the result of the merging of two super-dense objects, called neutron stars.

“Neutron stars are amongst the most bizarre objects known to science and are incredibly dense,” said Dr Robert Priddey, another member of the team. “A tea-spoon full of neutron star material would weigh tens of billions of tons. Their intense gravitational fields provide huge reservoirs of energy which we believe can power GRBs when two neutron stars merge together to form a black hole.”

The Hertfordshire team’s new result adds a further, unexpected twist to the tale: a significant proportion of short bursts seem to originate from galaxies much more local to us than those previously observed. These nearby short bursts, could, like their more distant brethren, result from the catastrophic collision of neutron stars, though if so then their outbursts must be much weaker. Alternatively they could be a fundamentally different kind of explosion. A prime candidate could be an exotic object called a magnetar — a lone neutron star with a magnetic field a hundred thousand billion times that of the Earth - tearing itself apart due to enormous magnetic stresses.

“An example of such an explosion was seen a year ago coming from a magnetar in our own Galaxy, the Milky Way, so it seems reasonable to expect they should occur occasionally in other galaxies too,” said Bob Chapman, a graduate student working on the project as part of his PhD research: “If so, they would look very much like short-duration GRBs.”

“Although we still don’t know for sure what produces the short-duration gamma-ray bursts, this is a crucial breakthrough because in astronomy knowing where something occurs is often the decisive step towards understanding it,” said Dr Andrew Levan, another Hertfordshire astronomer involved in the discovery.

Helene Murphy | alfa
Further information:
http://www.herts.ac.uk

More articles from Physics and Astronomy:

nachricht A tale of two pulsars' tails: Plumes offer geometry lessons to astronomers
18.01.2017 | Penn State

nachricht Studying fundamental particles in materials
17.01.2017 | Max-Planck-Institut für Struktur und Dynamik der Materie

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>