Spangenburg, Ray

1939

• Carl Sagan
• The history of science from 1946 to the 1990s
• A look at Mars
• Barbara McClintock
• Disease fighters since 1950
• If an asteroid hit Earth
• Modern science, 1896-1945
• Propaganda
• Space exploration
• The history of science from 1895 to 1945
• Wernher von Braun
• A look at Jupiter