Aero capture
Intro
Aero capture is a technique to reduce the delta V required for interplanetary travel significantly by using the atmosphere of the planet to capture a vehicle on an injection trajectory as opposed to doing a circularization burn. It requires a high degree of accuracy in the trajectory and puts demanding requirements on a heat shield.
Although the delta V gains are considerable, they are limited somewhat because a more robust heat shield is required for cooling. Additionally because of the precision required in approaching the planet it could potentially represent an increased risk in the mission. A less demanding form of breaking is often used in planetary probes called aerobraking.
See Also
Discussion at new mars
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