Unusual Chemical Compositions of Noctilucent-Cloud Particle Nuclei

• Published in: International Astronomical Union Colloquium
• Main Author: Hemenway, Curtis L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1971
• Subjects: Kiruna
• Online Access: http://dx.doi.org/10.1017/s0252921100049186; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0252921100049186

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 that most of the high-density particle nuclei have atomic weights greater than iron.