MICROGRAVITY Satellites in orbit are in free fall -accelerating radially toward earth at the rate of free fall Deviations from zero-g Atmospheric drag x=0.5 (C Ao a-ap Gravity gradient 义=-XW2义=yW2艺=2Ww Spacecraft rotation x=x22=202 (rotation about Y axis) Coriolis forces x=∠z0y=02=-zXOMICROGRAVITY 8 • Satellites in orbit are in free fall - accelerating radially toward earth at the rate of free fall. • Deviations from zero-g – Atmospheric drag – Gravity gradient – Spacecraft rotation (rotation about Y axis) – Coriolis forces 5 2 2 0. U a Z m C A x D ¸ ¸ ¸ ¸ ¸ ¹ · ¨ ¨ ¨ ¨ ¨ © §   x xw 2  x  y w 2 z 2zw 2  x x Z2 z z Z2  x 2 z Z  y o z  zxZ