John Winthrop, first governor of Massachusetts Bay Colony, recorded journal entry in 1639 and considered America's first UFO Sighting: "...a sober, discreet man, and two others, saw a great light in the night at Muddy River. When it stood still, it flamed up, and was about three yards square; when it ran, it was contracted into the figure of a swine: it ran as swift as an arrow towards Charlton [Charlestown], and so up and down [for] about two or three hours." A footnote added by James Savage in an early edition of Winthrop's Journal, offers possible explanation. "It is safe to deduce that the UFO witnesses had seen or heard swine on the same day they observed the great light. Thus, the lights resembled a common animal, making it probable they saw ignis fatuus mirage phenomena in the darkness." It may have been only a mirage, but significant enough, Winthrop recorded sighting in his private journal.