The Long Tail by Chris Anderson

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    Astrophysicists had long theorized that when a star explodes, most of its energy is released as neutrinos—low-mass, subatomic particles that fly through planets like bullets through tissue paper. Part of the theory is that in the early phase of this type of explosion, the only observable evidence is a shower of such particles; it then takes another few hours for the inferno to emerge as visible light. As a result, scientists predicted that when a star went supernova near us, we’d detect the neutrinos about three hours before we’d see the burst in the visible spectrum.
    The way to test this correlation between neutrinos and visible light was to make both observations and measure the time difference between them. But the problem with the optical part of these paired observations was that you had to be looking in the right part of the sky. This wasn’t much of a problem for the neutrino observatories. Because of its spherical layout, the detector hall of Kamiokande could record neutrinos penetrating the Earth regardless of which direction they came from. Yet to see the explosion in visible light, a telescope would have to be pointed at the exact right spot at the exact right time. And, needless to say, there was an awful lot of sky to watch.
    There just weren’t enough professional astronomers who could observe enough of the heavens to have much, if any, chance of spotting such an event. But there were thousands of amateur astronomers all too happy to do that job themselves. Armed with relatively inexpensive computer-guided telescopes with Dobsonian optics, which allow quite large apertures (twelve inches is not unusual) in telescopes less than five feet long, and sensitive CCD (charge-coupled device) sensors that can collect more light than the human eye, contemporary amateur astronomers can photograph the skies better than astronomers with house-sized telescopes could a century ago.
    The first person to see Supernova 1987A was an observer somewhere between the amateurs and the pros. Ian Shelton, a Canadian grad-school dropout, was housekeeping an observatory in the Chilean Andes in exchange for time on its twenty-four-inch telescope when academic astronomers weren’t using it. One of those free times was the windy night of February 23. That night Shelton decided to use the telescope to run a three-hour exposure on the Large Magellanic Cloud.
    As it happened, exactly 168,000 years earlier and exactly 168,000 light-years away, a star had exploded on the edge of the Tarantula Nebula. From Earth and Shelton’s view, however, the explosion looked like it was happening right then: a splash of light suddenly appearing in one corner of the Cloud where nothing of note had been before. Shelton stared at the photographic plates for twenty minutes before heading outside to see it with his own eyes. Sure enough, there it was: the first supernova to be witnessed by the naked eye since 1604.
    The connection between Shelton and the Kamiokande II observatory is one of time. The neutrino observatory spotted its burst at 7:35Universal time. Shelton observed the first bright light around 10:00 Universal time—a little less than three hours after the neutrino shower. So far, right on theory. However, could it have shown up even earlier, before Shelton was watching?
    Fortunately, two other dedicated amateur astronomers were at work that night using smaller, nonprofessional telescopes. In New Zealand, Albert Jones, a veteran credited with more than half a million observations, had taken a good look at the Tarantula Nebula at 9:30 UT but had seen nothing unusual. Robert McNaught, another amateur, photographed the explosion at 10:30 UT in Australia, confirming Shelton’s timing. So the light arrived somewhere between 9:30 and 10:00.
    That is how one of the greatest astronomical discoveries of the twentieth century unfolded. A key theory explaining how the universe works was confirmed thanks to amateurs in New Zealand and