Between 1969 and 1972, NASA deliberately steered spent pieces of Apollo hardware into the Moon. Empty lunar module ascent stages and spent Saturn V third stages were aimed at the surface and allowed to crash. The point was not theatre. Each impact was a calib…
In the late 1960s, a set of United States satellites built to watch for clandestine nuclear weapons tests began recording brief flashes of gamma radiation that matched no bomb. The flashes came from beyond the solar system. Decades later, after a long argumen…
In 1987 a star exploded in a nearby galaxy, and detectors deep underground caught the burst of neutrinos roughly three hours before any telescope on Earth saw the light arrive. The star was Sanduleak -69 202, a blue supergiant in the Large Magellanic Cloud, a…