Topic summary
Boostback burn
Extracted from the Wikipedia article SpaceX reusable launch system development program.
The reusable launch system technology was initially developed for the first stage of Falcon 9. After stage separation, the booster flips around (an optional boostback burn reverses its course), a reentry burn sheds gravity-induced speed to prevent stage overheating as the spacecraft reenters the thicker part of the atmosphere, and a landing burn accomplishes the final low-altitude deceleration and touchdown.