to the Royal Society in 1748. The period of the oscillation was the same as the time it took for the nodes of the orbit of the Moon to complete a revolution around the ecliptic, and Bradley surmised correctly that it was due to the effect of the Moon on the oblate shape of the Earth, causing the axis of the Earth to wobble:

I suspected that the moon's action upon the equatorial parts of the earth might produce these effects: for if the precession of the equinox be, according to Sir Isaac Newton's principles, caused by the actions of the sun and moon upon those parts,

0 0

Post a comment