MadSci Network: Physics |
Actually, the Apollo command module was very carefully designed to be stable with the rounded bottom pointing downward. The bottom of the capsule is designed so that if it tilts slightly clockwise, the right side of the heat shield becomes more flat-on to the oncoming air, while the left side is at an angle to the incoming air. Therefore air pushes harder on the right side than the left, and this rights the spacecraft.
The command module also had a system of small computer-controlled rockets which fired to keep the spacecraft aligned properly during re-entry.
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