This morning at 6:12 am PST, the Solar Impulse solar-powered airplane took off from San Francisco’s Moffett Airfield, beginning the first leg of its planned flight across the U.S.

The aircraft was piloted by Bertrand Piccard (and still is, at the time of this posting). He will be sharing piloting duties throughout the course of the 2013 Across America mission with fellow Solar Impulse team member André Borschberg. The mission will be broken into five legs, with the plane making stops at select American cities between each one. It is expected that the final leg of the journey will begin in early July.

Officially known as HB-SIA, the single-passenger Solar Impulse aircraft incorporates 11,628 solar cells on the top of its wing and horizontal stabilizer. These power its four 10-hp electric motors, and also charge its 400 kilograms (882 lb) of lithium batteries – allowing it to fly at night.

It should be completing the first leg of the mission when it lands in Phoenix, Arizona this Saturday (May 4th). Live video being streamed from the aircraft can be seen below.

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