Rick Doe, payload program manager at SRI International, discusses the Enhanced Tandem Beacon Experiment during a NASA prelaunch technology TV show for the Space Test Program-2 (STP-2) mission at NASA’s Kennedy Space Center in Florida on June 23, 2019. The experiment’s two CubeSats will work with six other satellites to study irregularities in Earth’s upper atmosphere that interfere with GPS and communications signals. It is one of NASA payloads scheduled to launch on a SpaceX Falcon Heavy rocket from Launch Complex 39A beginning at 11:30 p.m. EDT on June 24, 2019. STP-2 is managed by the U.S. Air Force Space and Missile Systems Center.