[neilep (OP)]

If we did not have the Moon....would we still have the tides ?



'Men are the same as women...just inside out !'

[Titanscape]

No, tides need the pull of the moon but winds and oceanic currents would still be there due to cool/warm motion generation. Perhaps there would be a sun tide. Is there one?

Titanscape

[neilep (OP)]

Thanks Bren...I had it in my mind that there might still be some tidal activity but you've cleared that up for me....that's a great follow up question though...can't see any reason why there should not be a Sun tide......perhaps someone can answer the question of the differences between the Sun and Moons gravitational effect on the Earth.

'Men are the same as women...just inside out !'

[chris]

You are quite right, the sun makes a big contribution to our tides.

Every 2 weeks we have spring (very high) and then neap (not so high) tides. The spring tides coincide with the new and full moon - i.e. when it is alignment with the sun. The gravitational effect of both bodies produces the much larger tide you see. During neap tides the half moons indicate that the moon is at 90 degrees to the sun-earth axis and hence the tides are smaller because the 2 are not working together.

Chris



"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[tweener]

If the moon did not orbit the earth, there wouldn't be any tides (from the sun) because the gravitational pull from the sun would be constant.  There would be some extremely small tidal effects from the other planets, but I'm not sure they could even be measured.  I'm quite sure they would not be noticeable to anyone who didn't have advanced scientific instrumentation.

----
John - The Eternal Pessimist.

[neilep (OP)]

Oh...for a minute I thought that Chris and John disagreed but I understand now....thanks guys.

Would I be right in thinking that the moon has other effects too eg: spawning fish/coral etc ?....making people turn hairy once a month ?...female gooey bits ?....seems to me the lunar cycle has quite a number of repercussions that we may take for granted....I wonder what the planet and civilisation would be like without the moon...sorry...just pondering !!...suppose I better go to work.

'Men are the same as women...just inside out !'

[chris]

The term 'menses' - referring to a woman's periods - takes its name from the latin word for moon because people have long been aware of the similarity in length of the moon cycle (28 days) and the female menstrual cycle.

Intriguingly, caller research conducted by BT reveals that calls surge around the time of a full moon :
http://www.thenakedscientists.com/html/shows/2000.12.17.htm#phone

...but fortunately the werewolf theory needs work - you are no more likely to be bitten by a dog at the time of the full moon, compared with any other time of the month !

http://www.thenakedscientists.com/HTML/shows/2002.05.26.htm#1

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[Titanscape]

The Earth is small and distant from the sun, it orbits the sun therefore the centrifical forces, I think they are called resists the suns gravity, but then the oceans too except for the rotation of the Earth against orbit and beyond orbital rotation. Faster and slower. With the moon however the Earth is only wobbled by the moon and it revolves around our planet. Thus pull with little resistance due to centrifical forces because our oceans hardly have any.

There is another natural sattelite between the moon and Earth too.

Titanscape

[neilep (OP)]

quote:Originally posted by Titanscape

The Earth is small and distant from the sun, it orbits the sun therefore the centrifical forces, I think they are called resists the suns gravity, but then the oceans too except for the rotation of the Earth against orbit and beyond orbital rotation. Faster and slower. With the moon however the Earth is only wobbled by the moon and it revolves around our planet. Thus pull with little resistance due to centrifical forces because our oceans hardly have any.

There is another natural sattelite between the moon and Earth too.

Titanscape

Bren.....do tell...what is the other natural satellite between the earth and Moon ?...you don't mean my ego do you ? []

'Men are the same as women...just inside out !'

[tweener]

I think that "natural satellite" might be Bren!  Sounds high enough. []

----
John - The Eternal Pessimist.

[Titanscape]

Bren's quotes:
"Earth's second one is called Cruithne. It was discovered in 1986 and it takes a convoluted horseshoe path around our planet as it is tossed about by the Earth's and the Moon's gravity". From the BBC
 
"No, Cruithne is not a moon and it is not describing a horseshoe path about our planet. It is not tossed about by the Moon. This is a mess. Earth has only one natural sizeable satellite - the Moon.
Cruithne is an asteroid moving along a horseshoe-type orbit about the Sun locked in the mean-motion resonance with Earth (their orbital periods match). Cruithne never approaches the Earth closer than to a few millions kilometers..."
Posted by: Valeri on April 29, 2003 09:49 AM. FROM Tomski's site archives.

Titanscape

[neilep (OP)]

I found this http://burtleburtle.net/bob/physics/cruithne.html ....which is nice ;-)

'Men are the same as women...just inside out !'