Also, what do you call the process in which the stars seem to repeat in a pattern every 365 days?
211899
Elliptical means that it is oval shaped or a elongated circle
562808
Well, this is an interesting lesson in geometry, eh? Since the earth is a sphere (more or less) that rotates on an axis - the N & S points were chosen as the intersecting points for longitudinal lines of measurement - which all go back to the length of a day and segments thereof - as well as 360 degrees which were derived roughly from the concept of a 360 day year (it is actually 365+ but back in time the 360 measurement worked wonders for calculationsand thus it fit into geometry of all kinds .. including the longitudinal slices of the earth in 1 degree increments). If you chose to - you could select another two points each an oposite 90 degrees from the N and S poles (which made sense becauseof the magnetic N and the rotational axis). The other two points would be arbitrary. Somebody would have to mark those spots. A secondary longitudinal series could then overlay the primary longitudinal lines and create a kind of variable grid based on an arbitrary selection of the two secondary points. Actually ONE of those lines would lie on top of one of the primary (current) longitudianal lines and it would be a double use line or a kind of disection of hemispheres.  \nBUT\nIt would not be measuring anything very well because the secondary points are arbitrary and not related to anything else.  \nSO\nThe reason the latitude disectors came into play with their resulting grids over the face of earth'ssphere, was becuase they help measure something.  Since stars, the sun and the moon are  always - based on measured timepieces - in the same place and the same time repeatedly, you could measure the distance above the horizon to a star and figure out how far you were N or S of the equator - a halfway point from N to S.  It became easy this way to use the North Star to detect your position N or S by the angle of THAT star above the horizon becuase it was always amost right on top of the N Pole.  So the slices of LATITUDE N and S were critical to navigation. Once the clock was perfected to hold accurate time within a few seconds a month, the accuracy of E and W postion on earth relative to the stars also became possible.  If people did not need to know were they were on earth (especially ships at sea) there would have been no need for a good grid system.
464723
It is, by definition, random.  Repitition of a particular sequence of movements in a given timespan (although I don't know how you would measure them accurately in 3 dimensions) is a statistically possible, but highly unlikely, event.
457260
An equinox in astronomy is the event when the Sun can be observed to be directly above the equator. The event occurs twice a year, around March 20 and September 23. More technically, the equinox happens when the Sun is at one of two opposite points on the celestial sphere where the celestial equator and ecliptic intersect. In a wider sense, the equinoxes are the two days each year when the center of the Sun spends an equal amount of time above and below the horizon at every location on Earth. The word equinox derives from the Latin words aequus (equal) and nox (night).\n\nA solstice is either of the two events of the year when the sun is at its greatest distance from the equatorial plane. The name is derived from Latin sol (sun) and sistere (stand still), because at the solstice, the Sun stands still in declination, that is, it reaches a maximum or a minimum. The term solstice can also be used in a wider sense as the date (day) that such a passage happens. The solstices, together with the equinoxes, are related to the seasons. In some languages they are considered to start or separate the seasons; in others they are considered to be center points (in English, for example, the period around the June solstice is known as midsummer, and Midsummer's Day is the 24 June — now two or three days after the solstice).
580947
B.\n\nBut it is not actually correct.  %'s are generally figured on a standard 360 day calendar year, this problem uses 365
521302
Rotation period = 1 day\nOrbital period = 1 year
656280
It is a means of measurement of events that are taking place around us.   Think  of the days when people have relied on shadows produced by sun to be a measure of time.  They only understood that day and night repeat.  When the earth rotation of sun was understood, what we now term as 24 hrs a day came into being.  The past also was surmised to be at this time as Roman, mayan civilisation etc.,   hence wthout time the relative intervals of events cannot be placed and with new scientific inventions we are able to pin point happenings to part of seconds also.\nThe various calendars that have been made at different parts of the world also have taken events that have taken place as the basis or zero.   When scientific inventions result in exact no of rotations of earth that have taken place or earth got formed from the Sun, then that can be a basis and a new unit can be had for a fourth dimension.\nRamachandran V.
473565
calender was roman.  zodiac was astrologers from Nostradamus times 360 degrees I have no idea
429199
It depends on how you define "orbit". \n\nIf you define orbit to mean the time it takes the Moon to come back to the same point with respect to the Sun (new moon to new moon), that is a synodic month, which is 29.53059 days.\n\nIf you define orbit to mean the time it takes the Moon to come back to the same point with respect to a fixed star, that is a sideral month, which is 27.32166 days.\n\nIf you define orbit to mean the time it takes the Moon to come back to the same point with respect to the intersection of the equator and ecliptic, that is a tropical month, which is 27.32158 days.\n\nIf you define orbit to mean the time it takes the Moon to come back to its perigee, that is an anomalistic month, which is 27.55455 days.\n\nIf you define orbit to mean the time it takes the Moon to return to its ecliptical ascending node, that is a draconic month, which is 27.21222 days.
237036
The path you're talking about is called the 'ecliptic.' However, the sun doesn't follow the ecliptic but is instead its focus. That the planets all generally follow the ecliptic strongly suggests that they all formed at about the same time and within the same nebula from which they drew their material.
253774
It's a cluster of stars that mankind has connected with imaginary lines to make a picture or outline of some thing...all twelve of the zodiac signs (Taurus, Leo ,Gemini, etc.) are constellations.
235943
Yes, stars move, both on individual paths and as objects orbiting the galactic center. The is a star named Gliese 710 which will pass within a light yea of the sun 1.4 millions years from now.
24365
Why 12 Months?\n\n\nThe ancient man found that in a complete cycle of seasons there are twelve cycles of the moon, thus the cycle of seasons, now refered as YERA was mad of 12 months.\n\n365 Days Of A Year?\n\n\nAfter getting men more knowledgeable it was found that one complete cycle of seasons OR the year takes 365 days.\n\n\nAdvancement in observations and clculations suggested that one complete cycle is of 365.242 days, thus in order to kepp the seasons fall the same way on the fixed times it was deviced that one day may be add after four years in February.\n\n\nINTERESTIN\n\n\nThe exact measure of 365.242 days in a year with adjustment of one day every four year required another adjustment of one day at every hundred years. For that Feburary in the year 2000 was to be made of 30 days (one day of leap year and one day of leap century). Unfortunately computerisation in the 20th century could not get information of adding two days and thus we had to accept a clander for 2000 with loss of one day. It means now we have a disadvantage of one day in a complete cycle. This is go on increasing in future if not checked earlier. With this milliniums later June will fall in severe cold in the northen hamesphire.\n\n\nEquaual Days in a Month?\n\n\nThere had been different efforts on international level to depict a system in which every month starts the same day and every month has the same number of days but so far nothing could have been developed.
527652
The sun doesn't change its angle, but due to the movement of the Earth around the sun and due to the tilt of Earth about 23.5 degrees from its axis of rotation around itself, the sun appears to rise from a different location at the east every day. If you can visualize this movement of the sun rise from the east, you can understand why we have 4 seasons in the year. Let me explain it for you: Let me start from the spring season. On this day the sun is perpendicular to the equator. We call this event as the vernal equinox, which happens twice a year; Once on March 21, and once on September 21. On these dates the sun rises exactly at the location where the equator crosses the horizon when you look towards the East. Now from here on the sun starts to rise north of the equator gradually every day and with a different daily rate. This is true because the motion of the earth around the sun is not constant. When the sun rises above the equator or north of the equator 23.5 degrees, it becomes perpendicular to the tropic of Cancer, during which time the northern hemisphere enjoys more than 20 hours of sun light during the summer especially at the areas near the North Pole. In fact any body lives with the North Pole Arctic circle enjoys 6 months of sun shine which never sets except on September 21 when it goes below the horizon only to return on March 21 of the following year.\n\nNow when the sun is perpendicular to the tropic of cancer, it begins to go downward as at this time it has reached the maximum rise above the equator. On September 21, the sun again is above the equator and returns to the same point it was during the beginning of spring. The suns continues to go down below the equator until it reaches the tropic of Capricorn, at which time the sun rises from a location about 23.5 south of the equator. During this time the sun shines only 5 to 6 hours to countries that are far above or north of the equator. This whole movement of the sun occurs due to the tilt of the Earth axis around which it rotates on daily basis, and due to Earth rotation around the sun. Earth makes one revolution around the sun once every approximately 365.6 days. I hope that makes sense to you.\n\n \n.
31894
It's a cycle of death and rebirth. A star will eventually go supernova, explode, and create stardust. These elements condense over millions of years to form a new star and new planets. This simple fact leads many scientists to the conclusion that a higher being must exist since it seems so neat and convenient to be just random chance. It seems like too useful a cycle, in other words. Like it was designed as such.
190074
You can learn that something is moving.  Either the earth is rotating (true), or the sky is revolving around the earth (once thought to be true).  You can also measure the length of the siderial day.  That is the length of time it take for the earth to rotate reletive to the stars.  Our "day" of 24 hours is based on the sun's motion.  If we were to measure time based on the stars we would have a day of 23hours and 56 minutes.  You can measure the length of the day with star trails, although to really get the timing down might be hard.
30642
Some stars might have a solar system, but not all do.  Some stars are actually two "suns" orbiting around one another (called a binary star) but appearing to the unaided eye as a single star.  Some are even three stars together, such as alpha centauri, which is the closest "star" in the sky--though it is actually three stars that look like one.  Some are stellar clusters, where many of these "suns" are all bunched close enough to appear as one star.  Some are entire galaxies, with billions of stars, but so far away that they appear to be a single star from earth.  Some are stellar clusters, where many of these "suns" are all bunched close enough to appear as one star.\n\nSome things you might think are stars are actually planets.\n\nSome are dead "suns," where the fuel for the nuclear fusion that makes the sun burn has all been expended, leaving a big mass of iron, that glows white-hot for many years before turning dark.  If you look at these so-called "white dwarves" through a powerful telescope, you can see a faint ring of matter that has been blown away in the explosion that came when the star died.  Some stars are huge, and some are small.\n\nSome of the stars we have been able to see have solar systems of their own, which we detect by the slight wobble caused by the gravitational pull of the planet (or planets) as it orbits.