Please, detalize you question. Where on the Earth you are talking about gravity? Near bulge or near depression? Considering Earth rotation (centripetal acceleration) or not. Including motion of Moon or not? All in all, changes of g due to tides are small (of the order of 10^-7 g), but you should specify your question: where and when.

By the way, in reality bulges on Earth are not under where Moon is, but a little ahead it due to rotation of Earth (if to look from space behind passing overhead Moon if to see from rotating Earth) In some resonating bays - sometimes 6-12 hours behind passing Moon.

Also, indeed tides are higher when Sun (about 33 % contribution) and Moon (about 67%) act on one line with Earth tides (so called "spring" tides" -nothing to do with the seasons). Then tides are about 3 times stronger (regardless if it is full or new moon) than when Sun and Moon are at 90 degrees to each other (67-33=34%) - so called "neap tides".

• Re: Re: earths gravity. - libbie468 - February 22, 2001 - 00:40 UTC
  • Re: Re: Re: earths gravity. - alexander - February 22, 2001 - 01:30 UTC