Subscribe to our free daily newsletters
. 24/7 Space News .

Subscribe to our free daily newsletters

Dark Matter Constituent May Have Lit First Stars

Head of the "Guitar Nebula", imaged with the HST Planetary Camera in 1994 and 2001, containing a fast moving pulsar followed by a tail of gas. The dark matter particles discussed in the Biermann-Kusenko paper can explain the long-standing puzzle of pulsar velocities leading to such cone-shaped nebula features. Image: Hubble Space Telescope, Shami Shatterjee 2002.
by Staff Writers
Bonn, Germany (SPX) Mar 14, 2006
A form of the mysterious material known as dark matter could have helped to ignite the first stars in the universe.

German and U.S. scientists said if dark matter is made of a strain of low-mass particles called sterile neutrinos - whose decay accelerates the formation of molecular hydrogen - they could have caused the first stars to form as early as 20-million years after the Big Bang.

The light from those first stars could have been sufficient to ionize interstellar gas between 150-million and 400-million years after the Big Bang, rendering the universe transparent to electromagnetic radiation, including visible light.

The scientists Peter Biermann at the Max Planck Institute for Radio Astronomy, and Alexander Kusenko at the University of California, Los Angeles said they have conducted neutrino-oscillation experiments that suggest the existence of right-handed or "sterile" neutrinos. These particles cannot interact with visible matter directly, but they can interact by mixing with conventional neutrinos.

The number of sterile neutrinos is not known, but if each one has mass of a few thousand electron volts, equivalent to about 1 millionth of the mass of a single hydrogen atom, they could account for dark matter - the missing mass that comprises about 20 percent of the universe.

This new hypothesis could explain several astronomical mysteries, Biermann and Kusenko said. For example, their calculations show that sterile neutrinos could have been produced in the Big Bang in sufficient amounts to account for dark matter.

Also, the particles could explain the longstanding puzzle of pulsar velocities. Pulsars, or rapidly rotating neutron stars, emerge from supernova explosions preferentially in one direction at velocities as high as hundreds of kilometers per second sometimes more than 1,000 kilometers (640 miles) per second.

To date, the origin of such high velocities remains unknown, but the scientists said sterile neutrino emissions could explain the pulsar kicks - such as one such pulsar is exhibiting within a stellar formation called the Guitar nebula.

If dark matter comprises particles that reionized the universe, Biermann and Kusenko write in the March 17 issue of Physical Review Letters, the same particles streaming from a supernova would have created the cosmic guitar.

"The formation of central galactic black holes, as well as structure on subgalactic scales, favors sterile neutrinos to account for dark matter," Biermann said. "The consensus of several indirect pieces of evidence leads one to believe that the long sought-after dark-matter particle may, indeed, be a sterile neutrino."

Related Links
Physical Review Letters

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

Tricorder Could ID Alien Gems and Minerals
Pittsburgh PA (SPX) Mar 12, 2006
A geoscientist is developing an instrument using a sensing technique called Raman spectroscopy, which he said could help spacecraft or robotic surface rovers identify thousands of types of minerals on other planets.

  • Russia Signs Space Cooperation Deal With Europe
  • Space Tourism Companies Reaching For The Stars
  • Kinesix Selected By Bigelow For Launch of First Inflatable Space Module
  • SPACEHAB Joins List of NASA COTS Proposals

  • Building The First Martian Map Of The 21st Century
  • Years Of Observing Combined Into Best-Yet Look At Mars Canyon
  • Mars Rover Update: Opportunity Captures Panorama At Payson
  • Mars Reconnaissance Orbiter Safely In Orbit

  • Prep Begins For Next Ariane 5 Launch
  • Weather Forces Postponement For ST5 Launch
  • Fourth Time Is The Charm For Ariane 5
  • NASA ST5 Mission On Target For Tuesday Launch

  • Goodrich Delivers True Color Images On Japanese EO Satellite
  • International Symposium On Radar Altimetry To Meet In Venice
  • Satellites Ensure Safe Passage Through Treacherous Waters In Ocean Race
  • ESA Satellite Program Monitors Dangerous Ocean Eddies

  • To Pluto And Beyond
  • New Horizons Update: 'Boulder' and 'Baltimore'
  • New Horizons Set For A Comfortable Cruise Out To Jupiter And Pluto Transfer
  • Questioning Pluto

  • Dark Matter Constituent May Have Lit First Stars
  • Record-Breaking Luminosity Boosts Potential Of Tevatron Collider
  • 'Tricorder' Could ID Alien Gems and Minerals
  • Arecibo Detector Is Discovering Thousands Of Galaxies

  • SMART-1 Tracks Crater Lichtenberg And Young Lunar Basalts
  • Quantum Technique Can Foil Hackers
  • Noah's Ark On The Moon
  • X PRIZE Foundation And The $2M Lunar Lander Challenge

  • Trimble Introduces Quadband GSM/GPRS Version of the TrimTrac Locator
  • Getting Lost May Soon Become A Thing Of The Past
  • GIOVE A Transmits Loud And Clear
  • Lockheed Martin Flight Tests Paveway II Dual Mode Laser Guided Bomb

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement