BBC NEWS Americas Africa Europe Middle East South Asia Asia Pacific
BBCi NEWS   SPORT   WEATHER   WORLD SERVICE   A-Z INDEX     

BBC News World Edition
 You are in: Science/Nature  
News Front Page
Africa
Americas
Asia-Pacific
Europe
Middle East
South Asia
UK
Business
Entertainment
Science/Nature
Technology
Health
-------------
Talking Point
-------------
Country Profiles
In Depth
-------------
Programmes
-------------
BBC Sport
BBC Weather
SERVICES
-------------
EDITIONS
Tuesday, 8 October, 2002, 10:35 GMT 11:35 UK
Cosmic particles scoop Nobel Prize
Image captured using the Chandra x-ray telescope
A supernova captured using the Chandra x-ray telescope
Three scientists who have discovered new ways to study galaxies and stars have been awarded the Nobel Prize in physics.

Raymond Davis Jr and Masatoshi Koshiba take one half of the 10 million kronor award, and Riccardo Giacconi the other half.

Davis Jr, from the University of Pennsylvania, US, and Koshiba, from the University of Tokyo, detected tiny particles called neutrinos from within, and outside, the solar system.


The new knowledge has changed the way we look upon the universe

Academy statement
Their insights, and follow-up experiments by other researchers, have enabled science to confirm long-held theories about the nuclear reactions that go on inside the Sun.

Giacconi, a scientist from Washington DC, made instruments capable of detecting x-rays from outside our Solar System.

In a statement, the Royal Swedish Academy of Sciences said: "This year's Nobel laureates in physics have used these very smallest components of the universe to increase our understanding of the very largest: the Sun, stars, galaxies and supernovae.

"The new knowledge has changed the way we look upon the Universe."

Neutrino Find

It was first predicted that the neutrino might exist as early as 1930 - but it was 25 years before its existence could be proven.

The particle is formed during the nuclear fusion reactions at the heart of stars such as our own Sun, in which hydrogen is converted to helium.

Koshiba, AP
Koshiba (l) inspects the Super-Kamiokande Neutrino Observatory deep under ground
But neutrinos are ghostly particles with no electric charge and very little mass. They can pass through millions of kilometres of matter with no effect - though with a 600-tonne detector, Raymond Davis was able to identify some - just 2,000 in total - coming from the Sun.

This provided the proof that nuclear fusion lay at the heart of our star.

Koshiba was able to first repeat this finding and then extended it, when, in February 1987, he managed to detect a tiny number of neutrinos emitted by a distant supernova explosion.

Now the technique has spawned a new branch of astronomy - neutrino astronomy - which is used to study far-distant objects.

X-ray detector

Giacconi paved the way for modern X-ray astronomy, which provides spectacular images of the Universe.

All stars, including the Sun, emit radiation at various wavelengths, including x-ray radiation.

Giacconi, AP
Giacconi laid the foundations for modern X-ray telescopes like Chandra and Newton
Cosmic x-ray radiation does not get through the Earth's atmosphere, but Giacconi placed instruments in space and, for the first time, detected a source of X-rays outside our own Solar System.

Some of the x-ray sources he detected are now thought to contain black holes.

There are now two major X-ray telescopes in orbit, Chandra and the Newton.

Previous winners

Last year, the physics award went to three scientists for the discovery of the Bose-Einstein condensate, a new state of matter, in 1995.

Americans Eric A Cornell and Carl E Wieman and German scientist Wolfgang Ketterle created this ultra-cold gas that may one day help scientists develop smaller and faster electronic circuitry.

On Monday, Britons Sydney Brenner, 75, and Sir John Sulston, 60, and American H Robert Horvitz, 55, were awarded the Nobel medicine prize, for discoveries relating to the life cycle of cells.

 WATCH/LISTEN
 ON THIS STORY
Click here
to watch the Nobel Prize for physics announcement
See also:

09 Oct 01 | Science/Nature
10 Oct 00 | Science/Nature
Internet links:


The BBC is not responsible for the content of external internet sites

Links to more Science/Nature stories are at the foot of the page.


E-mail this story to a friend

Links to more Science/Nature stories

© BBC ^^ Back to top

News Front Page | Africa | Americas | Asia-Pacific | Europe | Middle East |
South Asia | UK | Business | Entertainment | Science/Nature |
Technology | Health | Talking Point | Country Profiles | In Depth |
Programmes