Activity Notes For related resources in Spanish, see the Explora Más en Español section below. Students find the Sun’s location in the sky for different points in time during an eclipse. They will then use mobile devices to measure lux before and during the eclipse to examine the impact a solar eclipse has on the energy received at Earth’s surface. Materials Mobile devices with light sensors (standard on most mobile/smart devices) iOS or Android lux meter app Interactive eclipse map Protractor,