Figure Caption: Aerial photograph of Arizona Meteor Crater (upper panel; view NW), ground photograph of a giant ejecta on the east rim of the crater (middle panel; view NW), and optical microstratigraphy of rock varnish from this giant ejecta (lower panel). Varnish-based age estimate indicates that the impact of the Meteor Crater occurred around 46 ka or earlier, which agrees well with cosmogenic Cl-36 age of 49.7 ± 0.85 ka (Phillips et al., 1991).