Featured Research

from universities, journals, and other organizations

New 'fix' for cosmic clocks could help uncover ripples in space-time

Date:
June 25, 2010
Source:
Jodrell Bank Centre for Astrophysics
Summary:
Scientists have developed a promising new technique which could turn pulsars -- superb natural cosmic clocks -- into even more accurate time-keepers. This important advance could improve the search for gravitational waves and help studies into the origins of the universe.

Pulsars appear to be able to switch between two states which differ in the current of charged particles flowing from the surface into outer space. This change in current results in a change of slow-down in their rotation rate, such that the pulsar 'brakes' faster (upper panel) when the currents are large and 'brakes' less fast when the currents are weak (lower panel). These currents also result in a change in the shape of the beam emitted by the pulsar, and hence in the shape of the pulse, or tick, as the beam crosses a radio telescope.
Credit: Michael Kramer, University of Manchester

An international team of scientists have developed a promising new technique which could turn pulsars -- superb natural cosmic clocks -- into even more accurate time-keepers.

This important advance, led by scientists at The University of Manchester and appearing June 24 in the journal Science Express, could improve the search for gravitational waves and help studies into the origins of the universe.

The direct discovery of gravitational waves, which pass over cosmic clocks and cause them to change, could allow scientists to study violent events such as the merging of super-massive black holes and help understand the universe shortly after its formation in the Big Bang.

The scientists made their breakthrough using decades-long observations from the 76-m Lovell radio telescope at The University of Manchester's Jodrell Bank Observatory to track the radio signals of extreme stars known as pulsars.

Pulsars are spinning collapsed stars which have been studied in great detail since their discovery in 1967. The extremely stable rotation of these cosmic fly-wheels has previously led to the discovery of the first planets orbiting other stars and provided stringent tests for theories of gravity that shape the Universe.

However, this rotational stability is not perfect and, until now, slight irregularities in their spin have significantly reduced their usefulness as precision tools.

The team, led by the University of Manchester's Professor Andrew Lyne, has used observations from the Lovell telescope to explain these variations and to demonstrate a method by which they may be corrected.

Professor Lyne explains: "Mankind's best clocks all need corrections, perhaps for the effects of changing temperature, atmospheric pressure, humidity or local magnetic field. Here, we have found a potential means of correcting an astrophysical clock."

The rate at which all pulsars spin is known to be decreasing very slowly. What the team has found is that the deviations arise because there are actually two spin-down rates and not one, and that the pulsar switches between them, abruptly and rather unpredictably.

These changes are associated with a change in the shape of the pulse, or tick, emitted by the pulsar. Because of this, precision measurements of the pulse shape at any particular time indicate exactly what the slowdown rate is and allow the calculation of a "correction." This significantly improves their properties as clocks.

The results give a completely new insight into the extreme conditions near neutron stars and also offer the potential for improving already very precise experiments in gravitation.

It is hoped that this new understanding of pulsar spin-down will improve the chances that the fastest spinning pulsars will be used to make the first direct detection of ripples, known as gravitational waves, in the fabric of space-time.

The University of Manchester team worked closely on the project with Dr George Hobbs of the Australia Telescope National Facility, Professor Michael Kramer of the Max Planck Institute for Radioastronomy and Professor Ingrid Stairs of the University of British Columbia.

The research was funded by the Science and Technology Facilities Council. Their Director of Science, Professor John Womersley, said: "Astronomy is unlike most other sciences, as we cannot go out and measure directly the properties of stars and galaxies.

"They have to be calculated based on our understanding of how the Universe works -- which means that something as significant as being able to use pulsars as cosmic clocks, a new standard for time measurement, will have far-reaching consequences for advancing science and our understanding of the Universe."

Many observatories around the world are attempting to use pulsars in order to detect the gravitational waves that are expected to be created by super-massive binary black holes in the Universe.

With the new technique, the scientists may be able to reveal the gravitational wave signals that are currently hidden because of the irregularities in the pulsar rotation.

Head of the Pulsar Group at The University of Manchester Dr Ben Stappers said: "These exciting results were only possible because of the quality and duration of the unique Lovell Telescope pulsar timing database."


Story Source:

The above story is based on materials provided by Jodrell Bank Centre for Astrophysics. Note: Materials may be edited for content and length.


Journal Reference:

  1. Andrew Lyne, George Hobbs, Michael Kramer, Ingrid Stairs, and Ben Stappers. Switched Magnetospheric Regulation of Pulsar Spin-Down. Science, 2010; DOI: 10.1126/science.1186683

Cite This Page:

Jodrell Bank Centre for Astrophysics. "New 'fix' for cosmic clocks could help uncover ripples in space-time." ScienceDaily. ScienceDaily, 25 June 2010. <www.sciencedaily.com/releases/2010/06/100624140910.htm>.
Jodrell Bank Centre for Astrophysics. (2010, June 25). New 'fix' for cosmic clocks could help uncover ripples in space-time. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2010/06/100624140910.htm
Jodrell Bank Centre for Astrophysics. "New 'fix' for cosmic clocks could help uncover ripples in space-time." ScienceDaily. www.sciencedaily.com/releases/2010/06/100624140910.htm (accessed October 23, 2014).

Share This



More Matter & Energy News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

3D Printed Instruments Make Sweet Music in Sweden

3D Printed Instruments Make Sweet Music in Sweden

Reuters - Innovations Video Online (Oct. 23, 2014) — Students from Lund University's Malmo Academy of Music are believed to be the world's first band to all use 3D printed instruments. The guitar, bass guitar, keyboard and drums were built by Olaf Diegel, professor of product development, who says 3D printing allows musicians to design an instrument to their exact specifications. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) — Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Jet Sales Lift Boeing Profit 18 Pct.

Jet Sales Lift Boeing Profit 18 Pct.

Reuters - Business Video Online (Oct. 22, 2014) — Strong jet demand has pushed Boeing to raise its profit forecast for the third time, but analysts were disappointed by its small cash flow. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) — As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
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