[填空题]
The Moon orbits the Earth such that the sxbqycxc ah rmm99,,m y8m5 9 od2(lx2yame s,dz*/gv b yl(voq.qn3ide always faces the Earth. Determine the ratio of the Moon’s spin angular momentum (about its own axis) to its orbital angular momentum. (In the latter case, treat the Moon as a partbvg.3qvn(l qdo* /z,yicle orbiting the Earth.) $\times10^{ -6}$