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IAU Commission 21



IAU Commission 21 consists of some hundred members with professional interest in the light of the night sky. The diffuse components of the light of the night sky encompass a variety of physical phenomena over the full range of cosmic distance scales. From the Earth outward they include airglow in the Earth's atmosphere, scattering and thermal emission from the interplanetary dust cloud (zodiacal light), emission from the interstellar medium, integrated starlight, diffuse galactic light, diffuse emission in other galaxies and extragalactic background radiation. The purpose of Commission 21 is to facilitate research in these areas among the worldwide astronomical community. The Commission sponsors colloquia and symposia on these topics and supports related efforts in other commissions in the IAU. 

Commission 21 is part of Division III, Planetary Systems Science, which also includes Commissions 15, 16, 20, 22, 51, and 53.

Its Organizing Committee, vice-president and president carry out the business of the commission.


For the 2006-2009 triennium

President: Adolf Witt (USA)
Vice President:
Jayant Murthy (India)

Organization Committee Members: Jack Baggaley (New Zealand), E. Dwek (USA), Bo Gustafson (USA), Anny-Chantal Levasseur-Regourd (France), I. Mann (Japan), Kalevi Mattila (Finland), Junichi Watanabe (Japan)



Business Meeting at GA 2006 Prague, Minutes

Working Group: to review the need for an update of the comprehensive review of the “Light of the Night Sky”: “1997 Reference of Diffuse Night Sky Brightness”  chaired by A.-Ch. Levasseur-Regourd.


Updated: 2006/Sept/20