Ballistic reentry
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A ballistic reentry is a re-entry of an atmosphere that relies solely on drag within the atmosphere to slow the vehicle. By contrast, the U.S. space shuttle relies heavily on aerodynamic lift for its reentry, both vertically, to prolong the reentry process, and horizontally, to dissipate energy into a series of S-turns. The U.S. Mercury and Soviet Vostok spacecraft used a ballistic reentry. The U.S. Gemini and Apollo spacecraft and Russian Soyuz spacecraft use a lifting reentry, where aerodynamic lift makes for a gentler and aimable reentry, but have a backup ballistic reentry mode, used most recently on the Soyuz TMA-1 mission.