Why is Uranus tiltes sidewards???
359195
All planets are tilted, just not to that extreme...   It is more than likely that it had a close encounter with a large object in its past.  But what the crap do you mean that it moves sidewards?  Its in a relatively normal orbit, how does it move sideways?  I think a more interesting question is why does Venus spin clockwise?
338419
First, all planets in our solar system are tilted, although Mercury isn't tilted much.  And yes, this is what causes seasons.\n\nWe can observe seasonal changes (growing and shrinking of polar ice caps and the dust storms they seem to induce) on Mars.  I believe Neptune also has very strange seasons that we don't know much about.\n\nOn a bigger, gaseous planet like Jupiter though, although it tilts we wont see much in the way of seasons because it's atmosphere is affected by many other things that make it turbulent as is.\n\nIn the case of Venus, it has such a wild greenhouse effect (and might be close to being perfectly upside down, I can't recall) that I don't think we will see much in the way of seasons there either.
250788
Because they are tilted with respenct to both the earth's orbit and with respect to Saturn's orbit. This means that we sometimes see them edge-on. But when Saturn has gone about 90 degrees further in its orbit, we will see the edges from a more open viewpoint.
827722
The very slow rotation of Venus and the "backward" (retrograde) rotation might mean that it collided, in the past (probably toward the end of their formation), with an object of similar size.\n\nThe slow rotation may also have something to do with tidal lock with the Sun. Just an idea I am not sure.
363001
Some people think its because of the moon. The theory is that a huge asteroid hit the earth and then bounced of into orbit around the earth. This supposedly caused the earth to have a tilt to its axis.
1116527
The Moon rotates at just the right speed so that it always keeps one face pointed toward the Earth. Almost all moons in the Solar System keep one face pointed toward their planet. \n\nThe moon rises in the east, and sets in the west. It moves from east to west, right? If you think about it, you should realize that much of the moon's apparent motion is due to the spin of the earth. The moon appears to go around the earth about once a day. And, you probably know that the moon actually takes about a month to go around the earth. That's where we get the word "month."\n\nWhy don't you perform a simple observation. Look at the moon, some night, and see where it is with respect to the stars (or with respect to the sun). You don't need to know the stars very well, but you probably want to ignore the planets (Venus, Jupiter, and Mars, mainly, as their motion complicates this observation). Night after night, the moon moves against the background of stars. See if you can tell which way the moon is moving, against the background of stars.\n\nAnother simple observation would be to keep track of when the moon rises (roughly) or sets from night to night. Does it rise later each night, or earlier, or what?\n\nYou will see that the moon moves west to east, fairly rapidly. \nWhich way does the earth spin? Well, the stars, sun, moon, and planets all seem to be moving east to west. So the earth is spinning in the opposite direction, west to east. Hey, the moon is also moving west to east, coincidence? Well, the earth is moving around the sun from west to east. In fact all nine of the planets are moving around the sun from west to east. And, all of the planets, except Uranus (which is lying on its side) and Venus (which is spinning slowly backward), are rotating from west to east. And most of the moons, of the various planets, are orbiting their planets from west to east. And most of the asteroids are orbiting the sun from west to east.\n\nIt's not a coincidence. The Solar System started out as a cloud of dust and gas, and it was rotating from west to east. That's why most of its parts are still rotating and orbiting from west to east.
12525
There is a bulge of water on the side of the earth facing the moon because of lunar gravity. The previous explinations for the second bulge (on the opposite side of the moon) are incorrect.  The mass of the earth is constantly accelerating toward the moon, as they orbit eachother.  The smaller second bulge is a result of the earth accelerating away from the water, toward the moon
619864
If you were to view the Earth from above the North Pole, it will be rotating in an anticlockwise direction (i.e. West to East).\n\nEarth rotates about an axis, where 1 rotation equates to 24 hours (1 day). This axis is at a tilt of 23.45 degrees from the vertical. This tilting results in the seasons.\n\nA cool "video" can be found on: http://www.ncsu.edu/scivis/lessons/earthinspace3d/earth2.html
991212
If you follow astronomy like I do they are discovering everyday that the Solar System is not what we thought it was!  Our Universe actually may look round/spiral but if you tip it on its side it is pretty flat.  The answers relating to gravity are sort of right as well, but scientists have found just recently (few weeks) that some of our planets aren't perfectly round like everybody thought.  As we send more cameras into space the more we realize that what we thought was fact...is wrong!  Scientists are saying "oops" quite a lot this past year or two!  But yes, gravity plays a role, but when you look closely, they are not perfectly round and flat.  They have gigantic craters, mountains pointing up so high we can't even imagine it.  Our telescopes are getting more powerful as the computer age expands our capability.to see so much better.  Its a great field of study, especially today and tomorrow.  Things are changing our perspective on what we thought and what we are learning is the truth.  The sun may appear round, but it is gaseous so bellows, in and out, with flares and cool spots, same with the storms on Jupiter, they just recently realized that the Big Red Spot MOVES! Yep, science was shocked to learn that the Red Spot moves all over the planet!  So study and explore, the Digital Science Channel, and Discovery Channel is what every one should be watching, not The Simpsons, although Bart is a lot more funny.  But science is always changing, nothing ever remains the same!  Become an exployer of the Universe, and get paid for having fun in discovering new stuff all the time!
700627
The rotation of the moon just happens to be in the same sync as its orbit around the earth, so we only see one side. From the looks of the moon, though, it's speculated that the moon may have orbited faster or rotated faster, etc because there are crater marks on the earth side also, just not as many.\n\nActually, the moon is locked in its orbit so it always faces the Earth. The Moon is NOT perfectly round...technically its shaped like an egg due to the effects of gravity from the earth and possibly too when the moon was formed bilions of years agao after a huge meteor crashed into the earth and some of the Earth's molten core spewed out into space. Because the Earth is more massive than the Moon, it pulls on the Moon, "stretching" it closer to the Earth, throwing the shape and axis off, causing the moon unable to rotate on its own axis. This same effect is seen by the moons of other massive planets like Jupiter and Saturn. The same is effect is also seen with Mercury due to its close proximity the Sun and its massive gravitational effects.
53463
there is no direction in outer space.. thers is no up and no down.. we have this kind directin because of gravity.. our geographic north is the magnetic south and vice versa..
929189
I was just about to ask the same question. It is interesting that it is so evenly divided. Both sides think they are right. What keeps it from tilting one way or the other?
589353
Neptunes axis spins counter clockwise. the rest also do the same except three of them; venus:clockwise, Uranus: rotates on side, Pluto: rotates down
378554
Yup, one of the better theories right now is that Venus formed the "normal" way, but then turned over during the course of the evolution of the solar system.  The obliquity (tilt angle of each planet) can be effected by the orbits of all the other planets.  If you work the calculations you will find that Venus could have a dramatic change in it's obliquity over the course of time.\n\nIf you assume that Venus formed with the same type of tilt shown by the other inner worlds you can quickly show that the effects of the other planets will drive the tilt of Venus into a chaotic zone, where the tilt will rapidly change in an almost unpredictable manner (almost).  One way out of this unstable zone is if Venus were to turn all the way over, upside down (obliquity exceeds 180 degrees).  By doing so it would make Venus appear to have a spin opposite from the rest of the planets.\n\nThere are some issues with this theory, one of them is that Venus, while it does spin "backwards" also spins very slowly.  This is also hard to explain, but people have tried to change the rotation rate of venus through impacts, or near impacts with large, planetesimal-sized objects.  It may possible to help drive venus' tilt over with this method also.
11439
Uranus. Instead of having a North & South pole, it has an East & West pole.
347602
It's called 'retrograde' and it is has to do with how the orbits of Earth and Mars differ. Here's a good source for you, \nhttp://www.astro.uiuc.edu/projects/data/Retrograde/\nhttp://mars.jpl.nasa.gov/allabout/nightsky/nightsky04.html
46470
Acutally, the moon's phase isn't tilted, you're tilted.  If you saw the moon early this morning (1/26/06), it was a sliver over in the eastern sky. The bright portion looked like it had rotated counterclockwise. However, it's you, due to the rotation of the earth, that are tilted away from the axis of the moon. If you look at the moon closer to noon, the lighted portion will not appear to be tilted.