In 1976, renowned astrophysicist Carl Sagan brought a weird, reflective prop with him to the Tonight Show Staring Johnny Carson. The toy was a mockup of a solar sail—a revolutionary idea for space travel propulsion that eschews fuel. “[It] travels on the radiation and particles that come out of the Sun—the wind from the Sun,” Sagan explained to Carson, comparing the technology to how an ordinary sail boat moves through the ocean.
The Planetary Society is about to bring one of Carl Sagan's dreams to life. On May 20, the non-profit scientific organization--run by “Science Guy” Bill Nye--will be sending their LightSail spacecraft into lower Earth orbit for a 30-day test run. LightSail is essentially what it sounds like: a large sail that runs on sunlight. For this test, the Planetary Society will send up a tiny CubeSat that will deploy 32 meters2 of Mylar, and this “solar sail” can theoretically use renewable energy from the sun to propel the satellite through space.
Having a hard time getting motivated after a lazy, turkey-filled Thanksgiving break? We've got the perfect remedy for you. Take just five minutes from your workday to watch Wanderers, a short science-fiction film narrated by the late Carl Sagan that will reinvigorate you to explore the astonishing places within our celestial home.
For the September 1972 issue, Popular Science sat down for an interview with Carl Sagan about our rusty neighbor, Mars. For several months before then, NASA spaceprobe Mariner 9 had been sending back thousands of photographs of the planet's surface which raised more questions than they answered. The man who reminded us we are all made of starstuff dissected some of Mars' mysteries in his trademark educational and awe-inspiring way. Happy Carl Sagan Day!
Carl Sagan, everyone's favourite late astronomer, would have been 78 today. We can't think of anyone who inspired so many people to love science and the universe than good old Sagan. This year, we're looking back to an interview with the scientist that appeared in our September 1972 issue. At the time, he was really stoked about Mars.
