A Remark on Meteors.

Shock waves must play an important physical part when meteors traverse the earth's atmosphere. Preliminary estimates of 2,000,000° for the highest temperature reached in a meteor moving at 6o km/sec through air initially at 1800 absolute and of 70,0000 after the air's subsequent expansion are ex- cessive because of the lowering by dissociation and ionization of the effective ratio of specific heats. The actual temperatures, however, that arise from the shock wave must be very high