Simultaneous measurements of atomic O, O2, N2, and O3 in the region 90-110 km obtained from a rocket-borne mass spectrometer during the Aladdin 74 program indicate an ozone concentration as much as a factor of 50 times larger than predicted from the simple Chapman model. A possible explanation for the discrepancy is the formation of significant amounts of metastable ozone in this region of the atmosphere. The evidence for and the implications of such a metastable state of ozone are discussed.