A ballute is an inflatable balloon-parachute, made from a thin, flexible, inelastic membrane, that provides a means of aerobraking or aerocapture.

 

Typically, ballutes are pumpkin-shaped and wrinkled in appearance with longitudinal seams. One option is to have the main spacecraft engine run at low idle thrust during aerocapture to provide an aerodynamic "spike" to reduce heating on the ballute, although the ballute would be replaced after each flight. Stability and heat transfer considerations are critical, as ballutes are aerodynamically unstable at high Mach numbers, and radiative heat transfer is significant.

 

A dramatic example of aerocapture into Jupiter orbit using a ballute system was depicted in the movie 2010: The Year We Make Contact.