Viking 1 touches down on Mars; the first picture arrives twenty-five seconds later

For eleven months, NASA's Viking 1 had been traveling through space toward a planet no lander had ever safely reached. On July 20, 1976, it dropped through the thin Martian atmosphere on a 16-meter parachute that slowed it from 250 meters per second to 60 meters per second, before landing retrorockets brought it to a gentle jolt in western Chryse Planitia. Within minutes of touchdown, its camera began sending home the first photograph ever taken from the surface of Mars. It would keep working there for more than six years…