Solar Impulse 2 flies over San Francisco, Saturday, April 23, 2016. The solar-powered airplane, which is attempting to circumnavigate the globe to promote clean energy and the spirit of innovation, arrived from Hawaii after a three-day journey across the Pacific Ocean.
Solar Impulse 2 flies over San Francisco, Saturday, April 23, 2016. The solar-powered airplane, which is attempting to circumnavigate the globe to promote clean energy and the spirit of innovation, arrived from Hawaii after a three-day journey across the Pacific Ocean. Noah Berger AP photo
Solar Impulse 2 flies over San Francisco, Saturday, April 23, 2016. The solar-powered airplane, which is attempting to circumnavigate the globe to promote clean energy and the spirit of innovation, arrived from Hawaii after a three-day journey across the Pacific Ocean. Noah Berger AP photo