Olson and Jasinski calculated the moon's position and the lunar phase using astronomical software, and figured out exactly where Jackson's party, as well as the 18th North Carolina regiment, would have been at the time of the shooting, around 9 p.m. that night. They used Confederate almanacs in Richmond at the Virginia Historical Society, as well as battle maps by Robert Krick, a military historian who is an expert on the Battle of Chancellorsville, Stonewall Jackson and the Civil War in Virginia.
"Once we calculated the compass direction of the moon and compared that to the detailed battle maps published by Robert Krick, it quickly became obvious how Stonewall Jackson would have been seen as a dark silhouette, from the point of view of the 18th North Carolina regiment," Olson said.
Olson has used astronomy to solve other historical whodunits before. For example, he calculated the direction of moonlight on the night of Paul Revere's ride in 1775 to explain why Revere wasn't spotted by British sentries on a nearby ship, and exposed how moonlight allowed soldiers on the Japanese I-58 submarine to see, and sink, the USS Indianapolis in 1945.
"We are always interested in any historical event that happened at night — very often, the moon plays an important role, as happened here," Olson said.
This latest discovery may help restore the reputation of Barry and the 18th North Carolina regiment, which "unfortunately became famous and best known for accidentally wounding Stonewall Jackson,"Gillispie wrote.
Jackson's death was mourned not just by his troops and fellow generals, but by the civilian public in the South. He is still regarded as one of the greatest military tacticians in U.S. history, and he earned his famous nickname for leading his troops to stand against attackers like a stone wall.
Without a trick of the moonlight on that fateful night, Jackson may not have died, and historians debate whether the outcome of the Battle of Gettysburg, or even the whole Civil War, would have been different.
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