Category Archives: Space Exploration

The Cupola

In the sky is a castle, built in free fall, brick-by-brick, where the sun rises and sets every ninety minutes. The castle derives its energy from sunlight and recycles its water. Sealed against a vacuum, its inhabitants float and glide … Continue reading

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Raptor Interplanetary Transport Engine

Why has SpaceX chosen methane to fuel its Raptor rocket engine? Robert Goddard’s first rockets used liquid oxygen O2¬†or LOX and gasoline. The Saturn V moon rocket first stage used LOX and refined kerosene. The Saturn V second stage used … Continue reading

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First Deep Space Walk

In 1971 during Apollo 15’s return from Earth’s moon, astronaut Al Worden performed the first deep space walk nearly 200 000 miles from Earth to recover external service module film canisters that had mapped the lunar surface. Worden was able … Continue reading

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Into the Wind

  Last month, on 2016 April 18, a SpaceX Falcon 9 launch vehicle delivered a Dragon cargo capsule to the International Space Station and successfully landed its 48-m first-stage booster on the drone ship Of Course I Still Love You … Continue reading

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Dreaming Eyes Wide Open

1968. White Plains, New York. My mother takes me to a matinee of 2001: A Space Odyssey. The theater seats thousands and the movie plays continuously all day without commercials or trailers. A uniformed usher with a flashlight seats us. … Continue reading

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Kelly Twin Paradox

Yesterday astronaut Scott Kelly returned from nearly a year in free fall aboard the International Space Station to join his identical twin brother Mark back on Earth. Due to their different spacetime paths, I estimate that Scott aged about 9 ms … Continue reading

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A New Kind of Astronomy

One of the first things I did as a grad student in 1982 was tour the Laser Interferometer Gravitational Wave Observatory (LIGO) prototype on the Caltech campus about a block from my dorm. It was housed in a utilitarian L-shaped … Continue reading

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Hillary & Armstrong

You’re probably familiar with the iconic photograph of Edmund Hillary standing atop Earth’s highest mountain wearing an oxygen mask in air so thin the sky is almost black as space — but actually, Hillary’s companion Tenzing Norgay didn’t know how … Continue reading

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The Falcon Has Landed

Monday evening, the first of SpaceX’s 70 m (or 230 ft) Falcon 9 full thrust launch vehicles successfully deployed 11 satellites to low Earth orbit — and performed reversal, supersonic retrograde, and landing burns to return the first stage to … Continue reading

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The Martian

Ridley Scott’s The Martian (2015) is the best Mars movie I have yet seen. Genuinely faithful to Andy Weir’s popular novel, The Martian chronicles astronaut Mark Whatney’s struggle to survive on Mars, after being accidentally stranded there, and the efforts … Continue reading

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