Did you know that in 1974 Mariner 10 became the first interplanetary spacecraft to fly by one planet to reach another? As it flew by Venus, the gravitational pull of that planet placed Mariner 10 into a solar orbit that allowed it to fly by Mercury three times. Called a "Gravity Assist" trajectory, this requires precise navigation and is now widely used to reach other planets. Join Center for Earth and Planetary Studies scientist Andrew Johnston as he discusses the Mariner 10 spacecraft on display in the Time and Navigation exhibition.

Meet at the Museum's "Great Seal," in front of the Welcome Center, in the Boeing Milestones of Flight Hall on the first floor.

About the Ask an Expert lecture series: Every Wednesday at noon in the National Mall Building, a Museum staff member talks to the public about the history, collection, or personalities related to a specific artifact or exhibition in the Museum.

 Visitors at the National Mall building enjoy learning about the Pioneer 10 spacecraft from Museum scientist Andrew Johnston. Short Ask an Expert lectures such as this are offered once a week. Pioneer 10 was the first spacecraft to fly by Jupiter, the largest planet in the Solar System. How to attend

National Air and Space Museum in Washington, DC

6th St. and Independence Ave SW. Washington, DC 20560