Author Archives: John F. Lindner

This month is the 100th anniversary of Albert Einstein’s November 1915 discovery of the gravitational field equations of General Relativity, in which test masses move along the straightest possible paths (called geodesics) in spacetime curved by the density and flux … Continue reading →
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Ridley Scott’s The Martian (2015) is the best Mars exploration movie I have yet seen. Genuinely faithful to Andy Weir’s popular novel, The Martian chronicles astronaut Mark Whitney’s struggle to survive being inadvertently stranded on Mars and the efforts by … Continue reading →
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Many early aviators claim to have flown (or hopped) before the Wright brother’s four flights at Kitty Hawk on 1903 December 17. The Wright Flyer flew four times that day for up to one minute, with the Wright brothers famously … Continue reading →
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It was a privilege to spend the 2014-2015 academic year and summer on sabbatical at the University of Hawai’i in Honolulu. During the last week of July, I stood on the spectacular beach at Kailua near sunset and said to … Continue reading →
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As a kid, I enjoyed solving the “15 puzzle”, a sliding puzzle consisting of a 4×4 grid of 15 squares. However, I was amazed at a kind of 3D analogue of the 15 puzzle: Ernö Rubik’s 1974 masterpiece, which is … Continue reading →
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In a famous Star Trek misquotation, Mr. Spock says to Captain Kirk, “It’s life, Jim, but not as we know it”. Well, yesterday the New Horizons spacecraft returned its first closeup of Pluto, and it’s geology, but not as we … Continue reading →
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Next week the New Horizons spacecraft flies by the Pluto-Charon binary system. This week New Horizon photos indicate the dramatic differences between Pluto and Charon (where many astronomers pronounce the latter more like “Charlene”, the name of the wife of … Continue reading →
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The work of Newton and Laplace suggested to many that the solar system was like a giant clockwork, which was illustrated by beautiful mechanical models called orreries. The controversial Molchanov hypothesis avers that every oscillatory system evolves to a resonance … Continue reading →
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Last week, SpaceX conducted a successful pad abort test of its innovative Crew Dragon spacecraft. The hypergolic (= ignite on contact) MMH + NTO Super Draco engines accelerated Dragon from 0 to 100 mph in 1.2 seconds — that’s faster than … Continue reading →
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As a kid, I poured over diagrams in Popular Science magazine describing possible Grand Tours of the outer solar system (Jupiter, Saturn, Uranus, Neptune, and Pluto) made possible by a rare alignment of the planets. Unfortunately, budget cuts reduced the Grand … Continue reading →
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