Every second, each of the approximately 100 billion stars in our galaxy, including Earth’s sun, discharges trillions upon trillions of neutrinos—one of the tiniest particles known to science. As far as physicists now understand, neutrinos are elementary entities, meaning they
are indivisible. They also pass through just about everything unhindered, which means they have been almost impossible to observe. That is about to change. Starting in July, the new, $74-million Sudbury Neutrino Observatory will allow physicists, if not to see the mysterious subatomic particles directly, at least to observe what they can do.
The facility is designed to reveal the flashes of light emitted when
neutrinos smash into molecules of heavy water and break off an electron. If SNO scientists can then confirm their assumption that neutrinos have mass, that would go a long way towards explaining an enduring astrophysical mystery: why the total mass of all known celestial bodies is only a fraction of what scientists calculate the mass of the universe ought to be.
The story you want is part of the Maclean’s Archives. To access it, log in here or sign up for your free 30-day trial.
Experience anything and everything Maclean's has ever published — over 3,500 issues and 150,000 articles, images and advertisements — since 1905. Browse on your own, or explore our curated collections and timely recommendations.WATCH THIS VIDEO for highlights of everything the Maclean's Archives has to offer.