NASA’s MESSENGER spacecraft orbited Mercury for four years before its planned plunge and crash into the planet’s surface on April 30, 2015. On May 6, 2016, NASA, the USGS and their university partners showed what they had accomplished during the mission. They presented the first topographic map ever produced of Mercury, along with a color-enhanced view of its northern polar region. On May 9, 2016, Mercury's transit across the solar disk was visible from Earth—an astronomically rare event.