A NASA-backed study suggests the biblical Star of Bethlehem may not have been a star at all, but a rare comet recorded in ancient Chinese texts. The theory is reigniting debate over what truly guided the Magi on their historic journey. A NASA-backed study suggests the biblical Star of Bethlehem may not have been a star at all, but a rare comet recorded in ancient Chinese texts. The theory is reigniting debate over what truly guided the Magi on their historic journey.