Re: Did you feel it?

When the 'planetary alignment' event happened a short time ago -- May 5, 2000, if you recall -- there was huge speculation that the alignment of the planets would affect the Earth with widespread earthquakes, etc.

Lessons from Newton from www.spaceweather.com

The force of gravity is inversely proportional to the square of the distance between two bodies. This means that at twice the distance the force is reduced to one fourth. Because the tidal force exerted on one body by another is the difference between the gravitational force at the close side and at the far side of the body, it is inversely proportional to the cube of the distance. Thus, at twice the distance, the tidal force is reduced to one eighth.

As far as having an affect on Earth, the absolute gravitational force from another body in space isn't really important. It's the tidal effect that makes a difference. Take for example the Moon and Earth. The Moon has a certain over-all pull on Earth, which can be calculated by assuming Earth is all smashed down to a point at its center. In actuality, the Moon pulls harder than that on the side of Earth closest to it and less hard on the opposite side. It's this differential in gravitational force that causes the tides. It also causes a minor deformation of Earth itself.

The tidal forces exerted on Earth from the five planets on the other side of the Sun are vastly smaller than those exerted by the Moon or the Sun. In fact, with the planets in the position they were on May 5th, 2000, the largest tidal force from one of them will be from Jupiter, and it is about one five hundred thousandth (1/500,000th!!!!) the size of the tidal force exerted by the Moon on an average day! The difference in tidal force exerted by the Moon at apogee and perigee is about one hundred seventy thousand (170,000) times larger than the total tidal force exerted by Jupiter when its on the opposite side of the Sun. Another way of looking at it is that the Moon is about 42,000 km closer to us at perigee than when it's at apogee. On the average, the tidal force caused by Jupiter when it's on the other side of the Sun is equal to the increased tidal force caused by the Moon moving one quarter of a kilometer closer to us. We are much less affected by the tidal forces exerted by these planets when they are on the other side of the Sun, regardless of their alignment.

I hope this sheds some 'light' on the subject.

"Gravity. It's not just a good idea, it's the Law." - unknown joker