What is Gravitational Collapse?
• Can Earth capture a second moon? • How far does Earth’s Gravity Extend? • How far is the Moon? • Twinkle, twinkle little star How I wonder, what you are. • Teaching about seasons • Space Launches by Cannon–A • Space Launches by Cannon–B • The Southern Pole of the Sky • Do Astrologers use Wrong Positions for Planets? • Why does the Moon have bigger craters? • Why does Gravity Exist? • Atmospheric “Thermals”–Triggered by Electric Forces? • What would happen if Earth rotated faster? • Where do gravity of Earth and Sun balance? • The Ultimate Astronomy Tool • High Temperature in Cold Outer Space • Refraction of sunlight and starlight by the atmosphere • Advice to a would-be astronomer • The effect of the Color of Light on the Output of Solar Cells • What is “radiation”? • Height of the Atmosphere • How does the upper atmosphere get so hot? • History of the use of De Laval’s nozzle on rockets • Why don’t Space Rockets use Wings? • Distance of horizon on Mars • Stopping the rotation of
