At the South Pole, astronomers try to unravel a force greater than gravity that will determine the fate of the cosmos. Richard Panek reports for Smithsonian Magazine:
Twice a day, seven days a week, from February to November for the past four years, two researchers have layered themselves with thermal underwear and outerwear, with fleece, flannel, double gloves, double socks, padded overalls and puffy red parkas, mummifying themselves until they look like twin Michelin Men. Then they step outside, trading the warmth and modern conveniences of a science station (foosball, fitness center, 24-hour cafeteria) for a minus-100-degree Fahrenheit featureless landscape, flatter than Kansas and one of the coldest places on the planet. They trudge in darkness nearly a mile, across a plateau of snow and ice, until they discern, against the backdrop of more stars than any hands-in-pocket backyard observer has ever seen, the silhouette of the giant disk of the South Pole Telescope, where they join a global effort to solve possibly the greatest riddle in the universe: what most of it is made of.
For thousands of years our species has studied the night sky and wondered if anything else is out there. Last year we celebrated the 400th anniversary of Galileo’s answer: Yes. Galileo trained a new instrument, the telescope, on the heavens and saw objects that no other person had ever seen: hundreds of stars, mountains on the Moon, satellites of Jupiter. Since then we have found more than 400 planets around other stars, 100 billion stars in our galaxy, hundreds of billions of galaxies beyond our own, even the faint radiation that is the echo of the Big Bang.
Now scientists think that even this extravagant census of the universe might be as out-of-date as the five-planet cosmos that Galileo inherited from the ancients. Astronomers have compiled evidence that what we’ve always thought of as the actual universe—me, you, this magazine, planets, stars, galaxies, all the matter in space—represents a mere 4 percent of what’s actually out there. The rest they call, for want of a better word, dark: 23 percent is something they call dark matter, and 73 percent is something even more mysterious, which they call dark energy.
“We have a complete inventory of the universe,” Sean Carroll, a California Institute of Technology cosmologist, has said, “and it makes no sense.”
Scientists have some ideas about what dark matter might be—exotic and still hypothetical particles—but they have hardly a clue about dark energy…
[continues in Smithsonian Magazine]