rare matter

For a few minutes on Jan. 23, 2017, the coldest spot in the known universe was a tiny microchip hovering 150 miles over Kiruna, Sweden. The chip was small — about the size of a postage stamp — and loaded with thousands of tightly-packed rubidium-87 atoms. Scientists launched that chip into space aboard an unpiloted, 40-foot-long (12 meters) rocket, then bombarded it with lasers until the atoms inside it cooled to minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius) — a fraction of a fraction of a degree above absolute zero, the coldest possible temperature in nature. While the rocket … Read more