Abstract

Enhanced emissions at a wavelength of 6708 A were observed at Victoria, B.C. during the twilights following two rocket releases of lithium vapor trails into the atmosphere above Poker Flat, Alaska, on March 27 and March 28, 1976. Although the observed intensities were not as great as those observed on a previous similar occasion, there is little doubt that the enhancement was a direct result of the rocket releases. The average drift velocity of the lithium clouds was 5.9 m/sec. Vertical density distributions obtained using a Bracewell technique indicate an average scale height of 6.2 km, in good agreement with results previously obtained for an equilibrium distribution. The average height of maximum density for five of the best observations was 91.8 km.