First NASA lander to study Mars interior

A powerful Atlas 5 rocket was poised for lift off early on Saturday from Vandenberg Air Force Base in California, carrying to Mars the first robotic NASA lander designed entirely for exploring the deep interior of the red planet.

The Mars InSight probe was due to blast off from the central California coast at 4:05 a.m. PDT (1105 GMT), creating a luminous predawn spectacle of the first US interplanetary spacecraft to be launched over the Pacific.

The lander will be carried aloft for NASA and its Jet Propulsion Laboratory atop a two-stage, 19-story Atlas 5 rocket from the fleet of United Launch Alliance, a partnership of Lockheed Martin Corp and Boeing Co.

The payload will be released about 90 minutes after launch on a 301 million-mile (484 million km) flight to Mars. It is due to reach its destination in six months, landing on a broad, smooth plain close to the planet’s equator called the Elysium Planitia. That will put InSight roughly 373 miles (600 km) from the 2012 landing site of the car-sized Mars rover Curiosity. The new 800-pound (360-kg) spacecraft marks the 21st US-launched Martian exploration, dating to the Mariner fly-by missions of the 1960s. Nearly two dozen other Mars missions have been launched by other nations.

Once settled, the solar-powered InSight will spend two years—about one Martian year—plumbing the depths of the planet’s interior for clues to how Mars took form and, by extension, the origins of the Earth and other rocky planets.

InSight’s primary instrument is a French-built seismometer, designed to detect the slightest vibrations from “marsquakes” around the planet.