Caption:
Donald Howard Menzel (1901 - 1976), American theoretical astronomer and astrophysicist. He discovered the physical properties of the solar chromosphere, the chemistry of stars, the atmosphere of Mars, and the nature of gaseous nebulae. He was a named member of the In UFO conspiracy theories, Majestic 12 (or MJ-12), code name of an alleged secret committee of scientists, military leaders, and government officials, formed in 1947 by an executive order by U.S. President Harry S. Truman to facilitate recovery and investigation of alien spacecraft.