Can the moon's effect on gravity and tides vary or affect the speed of the earth's rotation i.e. speed it up/slow it down ever so slightly during monthly moon phases? If so, is it a stretch to assume that it might affect the space-time continuum ever so slightly as well?
131279
No, the apparent "phase" of the moon is relative to where you are on earth at a particular time and the moon's position in relation to the earth and the sun, it does not effect the earth's rotation.  That being said the moon has had an impact on the earth's rotation, and we can assume that it continues to exert the same gravitational forces it has through antiquity.  This isn't exactly true because the moon's orbit is actually getting larger at a rate of about 3.8 centimeters per year (negligible change)*. \n\nAs to stretching these facts to assume that it might affect the space-time continuum ever so slightly I have read several scholarly articles dealing with gravitational forces and their affect on time. Of all of these Stephen Hawking's were the easiest for me to understand and the most interesting to read.  You might want to check out his books "A Brief History of Time" and "The Universe in a Nutshell", both should be available at your local library.  Whether gravity exerted by the moon is strong enough to influence time on earth or not I’m not sure but I would assume so.  If I remember correctly the closer you are to a center of gravity the faster time passes relative to someone farther away.  The visible phases of the moon would still have nothing to do with the affect on time however.  \n\nThat was an interesting question, I hope my answer was of some use to you!\n\nRegards,\n\nArmus\n*thanks for correcting me on the orbital change Answer Guy.
212868
Not much.  The moon was not significantly that much closer to the Earth only 400 million years ago.  As such, while the tides would have been slightly higher and lower, there would not have been enough of a difference to make anything different for life.\n\nIn short four hundred million years ago the gravitational effects of the moon played the exact same roll they do today.
12392
"The moon does not circle the Earth once a day. The Earth circles the sun once a day. The Moon orbits the Earth about twice every 24 hours. That's why we have tides (high and low)."\n\nSAY WHAT?  Not even close.  There are junior high science teachers weeping over this "answer".\n\nThe earth rotates once a day on its axis.  That is the definition of a day - the time it takes for a planetary body to rotate once on its axis. \nThe earth circles the sun once a year - actually 365.24 days (which is why we have leap years).  That is the definition of a year - the time it takes for a planet to orbit the sun.  As you can tell, planetary years are longer or shorter depending on the distance from the sun.\nOur earth's axis is tilted.  The northern hemisphere is closer to the sun in the summer and farther in the winter.  This is how we get seasons.\n\nThe moon orbits the earth once every twenty-eight days, give or take an afternoon. The phases of the moon are caused by it being in a slightly different position everyday relative to the sun.  \nThe moon does cause tides - its gravitational pull causes the oceans to bulge out towards the moon.  However, there is a matching bulge directly opposite the moon.  THAT is why we have two high tides and two low tides a day.  In addition, the sun exerts a lesser pull, which interacts with the moons pull.\n\nSorry about that - had to correct the flagrant misinformation there.\n\nAs for your question - it is a weird effect, isn't it?  Especially when the moon is closer to a new moon.\n\nWhat happens is that our atmosphere scatters the light from the sun so that our sky is quite bright.(Why is the sky blue? has been discussed here many times).  However, the moon is reflecting enough light so that it is brighter than the surrounding sky and we see it.\n\nWhen the moon is less than full, there is very little light reflected off of the dark side of the moon (what light is reflected is earthshine!)  This light is not bright enough to outshine the sky.\n\nThink of a white sheet (in a dark room) that images are being projected onto.  The sheet will look opaque until someone shines a light onto it from the back that is brighter than the image projected from the front.  That is the basic effect that we are getting - the atmosphere is a sheet, with the sun and the moon both shining on to it.
615490
I don't think anyone has done the math to figure out how quickly it would happen but with out the moon the Earth's rotation on it's axis would not be stable where it is now.  If that got out of wack we would have some serious weather problems.  It's the tilt of the Earth not the distance from the sun that makes the difference between summer and winter.  So if that wobble that has the the northern hemisphere facing the sun in the summer and leaning away at 23 some degrees in the winter was screwed up we'd probably all die.  There's a good move called, odly enough< If we Had no Moon.  It's from the discovery channel, and you can buy it or just check their TV schedule, it comes on once or twice a year.
380716
Oh yeah, would it ever. Think about all the things the moon affects, everything womens menstration to the tides, if we didnt have a moon all of that would get out of balance. Think about all the organisms that live on the tide line, the ones that need both the air and the water there, how many animals count on that cycle just to live. Also alot of migratory paterns of animals depend on the moon as well. Thats a little off topic, but yeah the moon not being there would totaly screw up weather too!
236340
OK. Suppose something.. a transient black hole or worm hole or something, disappeared the moon. Gone! Poof!\nWhat would happen?\n\n1. There would be no major tides. The Sun's gravity would still produce some small tides but nothing like those caused by the moon. Sun tides are probably measured in fractions of an inch, I am not sure.\n2. There would be a period of earthquake activity as the Earth adjusted to the new center of gravity. The moon and Earth are connected by the pull of gravity. If this pull was broken, the tension would be released like a rubber band. The parts of the Earth facing toward and away from  the moon would drop back into their natural levels. This would create a shock wave that would probably be felt all over the Earth.\n3. The Earth would change its orbit around the sun. The Earth and the moon are actually orbiting around each other, but the centers of the ellipses are both inside the Earth because it is so much more massive than the moon. The moon weighs 1/81 of the Earth. If the moon disappeared, the Delta V of the Earth would change accordingly. It would depend on where the moon was when it disappeared. \n4. There would be untold social upheavals as societies panicked and everyone from astronomers to psychics to priests tried to explain what happened. Ophrah would make a bundle. ;-D
285091
Yes, the moon spins (or rotates) once for each revolution (orbit).  This happens because the moon is "tidally locked" to the earth.  \n\nThe moon exerts tidal forces on the earth because it pulls harder on the part of the earth closer to the moon and less hard on the part of the earth father from the moon.  The result is tides--the ocean bulges up on the side close to the moon because of the harder pull and actually bulges up away from the moon on the far side because of the weaker pull.\n\nThe earth also exerts tidal fores on the moon.  The moon has no oceans (and never did), but the solid rock of the moon bulged.  The moon used to spin much faster, but bulging and rotating causes friction, which slowed the moon's rotation until it keeps one face toward the earth.  Thus, the bulge is fixed in one place on the moon and no more friction!
400520
For any planet with a moon, the planet's mass can be approximated by GmM/r² = mv²/r = mrω² = mr(2π/P)², where G is the gravitational constant, m the mass of the moon, M the mass of the planet, r the distance between planet and moon, and P the period of the moon. The mass of the moon cancels out, leaving\nM = r³(2π/P)²/G\n\nThe masses of moonless planets have to be determined by Perturbation Theory, the effect of one planet's orbit on the orbits of other planets.\n\nThe diameter of another celestial object can be estimated by multiplying the angle subtended by the object by its distance from us.  A closer estimate is obtained by\nd/2 = Dsin(α/2) \nwhere d is the diameter, D is distance to the object, and  α is the subtended angle.
272144
From what i understand the earth will eventually leave the earth system altogether in a few hundred thousand years, this process is not however do to tidal drag. That force is responsible for slowing the rotation of the earth (and other planets) What most people don't understand is that the moon acts as a stabilizer for the earth. they degree of axial tilt would vary wildly. the equator may wind up as the north pole and go back again. planets without moons all experience this extreme wobble effect.
293632
Just as tides are effected by the moon, so are we because we are made up of 70 plus% water. It could also be the season change that is helping and maybe your food or hormones. Hey Im not doctor, but I love full moons! LOL! Heidi
238772
Since the Earth rotates relative to the Moon in one lunar day (24 hours, 48 minutes), each of the two bulges travels around at that speed, leading to one high tide every 12 hours and 24 minutes. The theoretical amplitude of oceanic tides due to the Moon is about 54 cm at the highest point. This is the amplitude that would be reached if the ocean were uniform with no landmasses and Earth not rotating.\n\nThe Sun similarly causes tides, of which the theoretical amplitude is about 25 cm (46% of that of the Moon) and the cycle time is 12 hours.\n\nAt spring tide the two effects add to each other to a theoretical level of 79 cm, while at neap tide the theoretical level is reduced to 29 cm.\n\nReal amplitudes differ considerably, not only because of global topography as explained above, but also because the natural period of the oceans is in the same order of magnitude as the rotation period: about 30 hours. If there were no land masses and the ocean bottom were flat, it would take about 30 hours for a long wavelength gravity wave to propagate halfway around the Earth (by comparison, the natural period of the Earth's crust is about 57 minutes). This means that, if the Moon suddenly vanished, and there were no land, the level of the oceans would oscillate with a period of 30 hours with a slowly decreasing amplitude while dissipating the stored energy. This 30 hour value is a simple function of terrestrial gravity the average depth of the oceans, and the circumference of the Earth.\n\nThe distances of Earth from the Moon or the Sun vary, because the orbits are not circular, but elliptical. This causes a variation in the tidal force and theoretical amplitude of about ±18% for the Moon and ±5% for the Sun. So if both are in closest position and aligned, the theoretical amplitude would reach 93 cm.
30811
Yes the moon is getting further away from us each year at a rate of aboout 4 centimetres a year.  The moon helps stabilise the Earth's rotation and stops us "flopping around".  In 2 billion years the moon will have moved far enough away to loose its influence.  The effect of this on the Earth is not known.
142411
The moon would have been slightly closer to the Earth 400 million years ago than it is now, but the difference in the gravitational effect would have been pretty negligible from the effect it currently has.\n\nFour hundred million years ago would have been right around the time animals were just beginning to leave the oceans and colonize land.  As you can imagine, tides would have a major impact on these organisms.\n\nHigh tides back then would have been slightly higher, and low tides slightly lower, but local geography would have had more effect than the actual gravity.  Bays and shallows channel the water movement and create greater variation than the moon's gravity does.  Today, places like the Bay of Fundy have tides that vary by 70 feet or more, while other sites may only change a few feet.  Tides might have been a few inches higher and lower back then, but local geography would have a greater effect.\n\nThe main influence the moon would have had would have already taken place.  By stabilizing the Earth's axis of rotation, shielding the surface from some large impacts, providing the tidal energy that helps circulate ocean nutrients and minerals, and providing reflected sunlight to assist nocturnal visual acuity and navigation, the moon was probably a key factor in the development of life on Earth.
58251
Actually only about 2/3 of the tides are from the moon's gravity, and about 1/3 are from the sun's gravity. \n\nThe reason there are about 2 high tides per day, is that the gravity field produced by the sun and the moon is not constant. The farther away from the moon you are, the less the gravity is. So water close to the moon gets pulled away from the earth (the force on the earth is less since the earth is farther away) and it gets pulled up in a pile we call a high tide. On the other side of the earth, the earth is pulled away from the water (since the earth is closer to the moon than the water on that side of the earth), leaving a pile of water on the far side of the earth, which is the other high tide. \n\nIn between these two piles of water, there are places where the water is not getting piled up. We say those places are experiencing a low tide. \n\nIt gets much more complicated than this of course. There are tides in the ground and in the atmosphere, in lakes and in rivers etc. There are places where there is one high tide a day or 3 or more or even no high tides per day (because of the response of the local area to the tidal forcing; governed by the bottom topography, coastline shape, etc). \n\nThere are high tides that are extra high because the sun and the moon line up (spring tides) and high tides that are not so high because the sun and the moon are at right angles, not working together (neap tides). There are ultra high tides when the moon is especially close (proxigean spring tides). There are effects of the other planets like Jupiter   and Mars in the tides. And so on.
396184
No.  The reason is a bit complex for someone not already familiar with the conservation of rotational inertia.  But the short answer is that Jupiter is probably moving very, very slowly away from the Sun.  Our moon is moving very, very slowly away from the Earth.  Each body that has satellites has what is called a "Roche limit".  Jupiter and Earth would be outside of the Sun's Roche limit so they will move slowly farther away.  Our moon is outside Earth's Roche limit and will move slowly farther away.   Mars is pretty cool.  Mars has 2 very small moons.  One, Diemos, is farther away from Mars and outside its Roche limit.  It will also continue to move farther away ever so slowly.  But the other moon, Phobos, is a bit closer and inside of Mars' Roche limit.  It will ever so slowly move closer to Mars until it spirals down and eventually collides.  COOL, huh?
122848
Anything with mass has gravity - the bigger the mass the bigger the gravity.  The moon which is quite small compared to earth has much less gravity - look at the footage of the sapcewalks.  Larger planets such as Jupiter or Saturn have much higher gravity - probably so much so that you'd be crushed under your own weight.\n\nThe moon's gravity affects the earth (most noticably in the tides) and to a much lesser extent the other bodies in the solar system affects the earth.
6283
The moons gravity is what causes ocean waves. It affects big bodies of water such as oceans or seas but as for water in a toilet I highly doubt because if you think about it, the moon's gravity doesn't effect pond water. The only thing that would affect toilet water is water pressure, and on the global scale the Corriolis Effect. But that only effects the direction of the water when flushed. So the most probable cause is the water pressure of your city.