Unusual Chemical Compositions of Noctilucent-Cloud Particle Nuclei

Curtis L. Hemenway
1971 International Astronomical Union Colloquium  
On August 8, 1970, two Pandora sounding rocket payloads were launched from the ESRO range in Kiruna, Sweden during a noctilucent cloud display. Large numbers of sub-micron particles were collected, most of which appear to be made up of a high-density material coated with a low-density material. Typical electron micrographs are shown. Particle chemical compositions have been measured by use of dispersive x-ray analysis equipment attached to a Philips EM 300 electron microscope and have revealed
more » ... and have revealed that most of the high-density particle nuclei have atomic weights greater than iron.
doi:10.1017/s0252921100049186 fatcat:ywjgeorwnzalppsec7o5bcscz4