
WASHINGTON, DC - MAY 9: In this handout provided by NASA, NASA Chief Scientist Ellen Stofan looks through a telescope with a solar filter to see the planet Mercury as it transits across the face of the sun as Kelly Fast of NASA's Science Mission Directorate looks on at NASA Headquarters on May 9, 2016 in Washington, DC. Mercury passes between Earth and the sun only about 13 times a century, with the previous transit taking place in 2006. (Photo by NASA/Joel Kowsky via Getty Images)


