In December 2020, the North York Moors National Park was officially named by the International Dark-Sky Association, an ‘International Dark Sky Reserve’, making it one of just 19 such reserves in the world.
The park stated:
“We’re officially one of the best places in the country to see stars, because of the low light pollution levels and clear horizons.”
Because of this, a stargazer in the reserve can view up to 2,000 stars at any one time.
Dark skies and dark matter
The observations of physicists and mathematics reveal that the movements of stars and galaxies can best be explained if the universe is made of much more mass than is at first evident or visible.
In fact, the invisible material has been estimated to comprise perhaps 90% of the mass of the universe. The ‘missing’ mass has been called ‘dark matter’; it is has no electromagnetic effect but does react to gravity.
The physicist Lord Kelvin as early as 1884 estimated that there was a difference between the mass of the visible stars and the estimated mass of the milky way galaxy.
Dark matter and its acronyms
There have been numerous hypotheses about the nature of dark matter. Physicists appear to have gained some amusement from the naming of candidate hypothetical objects and particles.
Acronyms such as ‘macho’ (massive astrophysical compact halo object) and ‘wimp’ (weakly interacting massive particle) have been put forward. Another possible dark matter particle, the ‘axion’, was named in part after a popular brand of US laundry detergent.
“I have no idea if the axion is real. Everything theoretical physicists do is speculative, and likely wrong, except for the things we get right.”
Research into dark matter
In June the Guardian reported on a project to detect dark matter in an old gold mine in Dakota. Physicist, Kevin Lesko, said:
“What is this great place I live in? Right now, 95% of it is a mystery”.
There have been numerous large hadron collider experiments at CERN in an underground tunnel over 25km long, beneath the Swiss Alps. In over ten years of research, researchers have not yet detected evidence of dark matter particles but have claimed that the research has narrowed down the area in which to look.
Dark matter closer to home
Over a kilometer beneath the North Yorkshire National Park, in the Boulby potash polyhalite and salt mine, is an underground laboratory, the Boulby Underground Laboratory (BUL). Amongst other research projects taking advantage of the low background radiation afforded by the deep cover, dark matter research has been carried out at here for the last two decades.
As with other centres involved in the search, BUL has experimented with various techniques and different equipment and shared its results in collaboration. But the search continues. In science, eliminating negatives can also be seen as progress.
One is reminded of another story about Lord Kelvin. He is reported to have said in a talk to the Royal Society in 1900:
“There is nothing new to be discovered in physics now. All that remains is more and more precise measurement.”
Within a few years of Kelvin’s statement, Max Planck and Albert Einstein had introduced quantum physics followed by the special and general theories of relativity. There was a revolution in physics.
There can be little doubt that more and more precise measurement is happening at Boulby and elsewhere, but as yet dark matter is proving elusive.
We don’t have a picture of the dark skies above Boulby as we rely on images that are provided royalty free to us. But if you have one that we could use, please do get in touch [email protected]