A solar-powered airplane took off from California for Arizona early Monday to continue its journey around the world using only energy from the sun.
The Swiss-made Solar Impulse 2 flew from Mountain View south of San Francisco shortly after 5 a.m. Monday for an expected 16-hour trip to Phoenix.
Swiss pilot Andre Borschberg was at the helm of the plane that began circumnavigation the globe last year.
Read More: Solar Impulse 2 Lands in California After Risky 3-Day Flight
Borschberg's co-pilot, Bertrand Piccard, also of Switzerland, made the three-day trip from Hawaii to the heart of Silicon Valley, where he landed last week.