IF YOU occur to cross by way of Antarctica later this 12 months, you may be greeted with a peculiar sight. Peel your eyes away from the penguins and also you may spot one thing uncommon floating within the sky: a balloon the dimensions of a stadium. Trailing beneath will probably be the most recent mad-sounding experiment designed to look for essentially the most maddening factor scientists have ever dreamed up – dark matter.
We reckon round 85 per cent of the universe’s matter is unique stuff that doesn’t replicate, emit or take in gentle, which is why it’s referred to as dark matter. The solely drive that this hypothetical stuff positively deigns to work together with is gravity, so far as we all know, which makes it extremely troublesome to detect. “When I gave talks on this in the 80s, I was telling people, ‘Oh, we’re going to figure this out in 10 years’,” says Katherine Freese, an astrophysicist on the University of Texas at Austin. Decades later, we’re nonetheless ready. “It’s obviously a harder problem than we realised.”
In the face of that onerous fact, dark matter hunters have change into ever extra ingenious. Attempts over time to pin down what it’s made of are burying vats of liquid xenon deep underground, measuring the straightness of lightning bolts, a plan to detect nanoscale explosions in minerals, analyzing historic rocks for dark matter scars and checking the James Webb Space Telescope’s observations for “dark stars”. All of which raises the query: are some strategies for dark matter searches a protracted shot too far? And at what level would we think about giving up the chase?
The first hints that …