Solar Impulse

In a huge first for aviation, a solar powered plane named the Solar Impulse took off early Friday morning from Moffett Field in Mountain View, Calif., to start the first leg of a pioneering cross-country flight.

The fuel-free plane is pictured, gliding by the Golden Gate Bridge as part of a test flight last month.

Pilot Bertrand Piccard gets ready for a trial flight through Morocco.

The Swiss-made plane came from Europe on a jumbo jet and was put back together in the Moffett Airfield hangar.

Twelve thousand solar cells are built into the wings, enabling the plane to fly 24-hours a day. The solar panels are able to gather enough power during the day to recharge the lithium batteries in order to provide power to the plane at night.

In a nighttime test flight, the Solar Impulse flies in proximity to the Bay Bridge in California.

In 2010, on one of its first test flights, the Solar Impulse flew from Payerne to Geneva in Switzerland.

The Solar Impulse took test flights through Switzerland in September 2010.

Pilots Andre Borschberg and Bertrand Piccard celebrate a successful test flight through Morocco after landing at Rabat-Sale Airport.

The Solar Impulse in a test flight over Belgium.

The Solar Impulse coming for a landing.

Pilot Bertrand Piccard's view out of the plane while crossing the Gibraltar straight.