It turns out the Mona Lisa is smiling after all—at least, according to scientists.
A new study from of the University of Freiburg has found that the mysterious woman at the center of Leonardo da Vinci’s most famous painting is generally perceived as happy by viewers. Researchers showed participants the painting’s lips unaltered, alongside eight other versions in which the Mona Lisa’s lips were modified to curve slightly upwards or downwards. Despite the purported ambiguity of her facial expression among art historians, the study determined that a majority of observers viewed the actual curvature of the Mona Lisa’s lips as an indication of happiness. An enduring mystery not addressed by the study is why, exactly, the woman is smiling to begin with.