In the pre-dawn hours of November 12, 1833, the sky over North America seemed to explode with falling stars. Unlike anything anyone had ever seen before, and visible over the entire continent, an Illinois newspaper reported “the very heavens seemed ablaze.” An Alabama newspaper described “thousands of luminous bodies shooting across the firmament in every direction.” Observers in Boston estimated that there were over 72,000 “falling stars” visible per hour during the remarkable celestial storm.The Lakota people were so amazed by the event that they reset their calendar to commemorate it. Joseph Smith, traveling with Mormon refugees, noted in his diary that it was surely a sign of the Second Coming. Abraham Lincoln, Frederick Douglas, and Harriet Tubman, among many others, described seeing it. It became known as “The Night the Stars Fell.”So, what was this amazing occurrence?Many of those who witnessed it interpreted it as a sign of the Biblical end times, remembering words from the gospel of St. Mark: “And the stars of heaven shall fall, and the powers that are in heaven shall be shaken.” But Yale astronomer Denison Olmsted sought a scientific explanation, and shortly afterwards he issued a call to the public—perhaps the first scientific crowd-sourced data gathering effort. At Olmsted’s request, newspapers across the country printed his call for data: “As the cause of ‘Falling Stars’ is not understood by meteorologists, it is desirable to collect all the facts attending this phenomenon, stated with as much precision as possible. The subscriber, therefore, requests to be informed of any particulars which were observed by others, respecting the time when it was first discovered, the position of the radiant point above mentioned, whether progressive or stationary, and of any other facts relative to the meteors.”Olmsted published his conclusions the following years, the information he had received from lay observers having helped him draw new scientific conclusions in the study of meteors and meteor showers. He noted that the shower radiated from a point in the constellation Leo and speculated that it was caused by the earth passing through a cloud of space dust. The event, and the public’s fascination with it, caused a surge of interest in “citizen science” and significantly increased public scientific awareness.Nowadays we know that every November the earth passes through the debris in the trail of a comet known as Tempel-Tuttle, causing the meteor showers we know as the Leonids. Impressive every year, every 33 year or so they are especially spectacular, although very rarely attaining the magnificence of the 1833 event.The Leonid meteor showers are ongoing now and are expected to peak on November 18. But don’t expect a show like the one in 1833. This year at its peak the Leonids are expected to generate 15 “shooting stars” per hour.November 12, 1833, one hundred ninety years ago today, was “The Night the Stars Fell.”The image is an 1889 depiction of the event.