In Roman mythology, Pluto is the god of the underworld. The planet received this name perhaps because it’s so far from the Sun that it is in eternal darkness.
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horizon |
equator |
ecliptic |
earth's orbit |
moon |
moonspath |
planets |
precession |
conjunction |
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the Horizon - depends where you are on the Earth - the Zenith - ditto - it is the point directly overhead , wherever you are the Celestial Equator - a projection of the Earths equator up into the sky ..the North and South Celestial Pole , ditto the Ecliptic - the plane of the Earth's orbit around the sun - or the path the sun makes in the sky , depending on how you look at it .The Ecliptic and the Celestial Equator would be the same if the Earth was not tilted on its axis - but it is ( which is why we have different seasons ) - and they are not - by 23 and half degrees the Ecliptic and the Celestial Equator cross at two points , the Spring and Autumn Equinoces All the planets and the moon have eliptical orbits but they are all more or less in the same flat plane with the sun ( except Pluto which is more wayward ) - so that viewed form Earth , they all take roughly the same path through the sky ( the Ecliptic ) and this path is divided up into twelve sections called the Zodiac afer the costellations on it which are mainly animals except Libra - Virgo ...Gemini ..... Aquarius isnt really an Animal either .. the Zodiac is what its still called ..... the moon orbits the Earth so relates to the Earth as it circles the Celestial Equator - so the path of the Moon is close to the Ecliptic but crisscrosses it twice a month |
Note that the daily rotation of the Earth causes each star and planet to make a daily circular path around the north celestial pole referred to as the diurnal motion. http://abyss.uoregon.edu/~js/ast122/lectures/lec02.html |
1. Using RA and decAll stars and other objects in the sky are at different distances from earth. But if we for a moment forgot that and instead imagined them on the inside of a great sphere surrounding the earth then we'd have something called a celestial sphere. Now what if we wanted to describe the positions of those stars and objects? Since the celestial sphere surrounds the earth, let's do a few things. First, extend the earth's equator out until it intersects the celestial sphere. Now we have the celestial equator. Do the same thing with the earth's poles and we have the celestial poles. On earth, we can measure latitude as how far north or south something is from the equator. If you are at the equator you are at 0° latitude. At the North Pole, you are at +90°. So latitude is measured from 0 to ±90°. We can do the same thing on the celestial sphere, but instead we call it declination. Declination is also measured from 0° at the celestial equator to ±90° at the celestial poles. A little tougher to translate is longitude. On earth we define it as how far east or west a place is from the Prime Meridian which is defined as a line beginning at the North pole, passing through Greenwich, England (UK), then ending at the South pole. There are historical reasons for that. But what about in the sky? Is there a 'Prime Meridian' up there? Yes, there is but first we need to define some other points in the sky.
And then there are those two times when the axis is not tilted towards or away from the sun (spring and fall) so it looks like the sun and ecliptic are crossing the celestial equator. The winter and summer points are called the solstices and the spring and fall points are called the equinoxes. Because springtime is a time of birth and renewal, the Spring or Vernal equinox was considered to be very important so it was natural that when astronomers were trying to figure out a 'Prime Meridian' for the sky that they would choose a meridian passing through the Vernal Equinox. Because the vernal equinox is the point in the sky where the ecliptic crosses the celestial equator from south to north or is ascending, we call these longitude-like lines 'lines of RA or right ascension.' So now we know where the 0 point or prime meridian is in the sky. How do we measure RA in the sky? Remember, on earth we measure longitude east and west from the Prime Meridian. In the sky, we measure it slightly differently. Earth is slowly turning on its axis -- once every 24 hours. Let's say that one day the Vernal equinox is crossing our local meridian (the line running north-south through the zenith, separates the sky into east and west). An hour later, we can imagine that crossing our meridian is another line of RA. And every hour after that, we have another line of RA overhead until we're back where we started. So we number these lines of right ascension in hours from 0 to 24. |
Ecliptic
Since the Earth's axis is tilted 23 1/2 degrees from the plane of our orbit around the Sun, The apparent motion of the Sun through the sky during the year is a circle that is inclined 23 1/2 degrees from the celestial equator. This circle is called the ecliptic and passes through 12 of the 88 constellations that we call the zodiac
Since the ecliptic is tilted 23.5 degrees with respect to the celestial equator, the Sun's maximum angular distance from the celestial equator is 23.5 degrees. This happens at the solstices. For observers in the northern hemisphere, the farthest northern point above the celestial equator is the summer solstice, and the farthest southern point is the winter solstice. The word ``solstice'' means ``sun standing still'' because the Sun stops moving northward or southward at those points on the ecliptic. The Sun reaches winter solstice around December 21 and you see the least part of its diurnal path all year---this is the day of the least amount of daylight and marks the beginning of the season of winter for the northern hemisphere. On that day the Sun rises at its furthest south position in the southeast, follows its lowest arc south of the celestial equator, and sets at its furthest south position in the southwest. The Sun reaches the summer solstice around June 21 and you see the greatest part of its diurnal path above the horizon all year---this is the day of the most amount of daylight and marks the beginning of the season of summer for the northern hemisphere. On that day the Sun rises at its furthest north position in the northeast, follows its highest arc north of the celestial equator, and sets at its furthest north position in the northwest. The seasons are opposite for the southern hemisphere (eg., it is summer in the southern hemisphere when it is winter in the northern hemisphere). The Sun does not get high up above the horizon on the winter solstice. The Sun's rays hit the ground at a shallow angle at mid-day so the shadows are long. On the summer solstice the mid-day shadows are much shorter because the Sun is much higher above the horizon. |
The Sun appears to drift eastward with respect to the stars (or lag behind the stars) over a year's time. It makes one full circuit of 360 degrees in 365.24 days (very close to 1 degree or twice its diameter per day). This drift eastward is now known to be caused by the motion of the Earth around the Sun in its orbit.
The apparent yearly path of the Sun through the stars is called the ecliptic. This circular path is tilted 23.5 degrees with respect to the celestial equator because the Earth's rotation axis is tilted by 23.5 degrees with respect to its orbital plane. Be sure to keep distinct in your mind the difference between the slow drift of the Sun along the ecliptic during the year and the fast motion of the rising and setting Sun during a day.
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discussed HERE |
more at NASA site - HERE |
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Most planets follow orbits that are more elliptical than Earth's. Pluto's orbit, Above: The orbits of Mercury (red), Earth (blue) and Mars (black). The solid lines indicate each planet's elliptical path around the Sun. The dotted lines show circular paths with the same mean separation from the center. Earth is almost exactly the same distance from the Sun at aphelion and perihelion, but the orbits of Mars and Mercury depart significantly from a circle. For more information, please visit Bridgewater College's Interactive Planetary Orbits web site |
Precession - or why the stars change gradually over centuries
Precession: Gravitation pull of the Sun and Moon causes a "wobble" in the Earth's axis with a period of 25,000 years (like pushing a gyroscope). This wobble is called precession and has the result of changing the point in the sky where the celestial poles are located and, therefore, changes the "pole star".
This motion was first recorded by Hipparchus in 100 B.C. who noticed differences between ancient Babylonian observations and his own. When the Babylonians were the world power in 2000 B.C., the vernal equinox was in the constellation Aries and the star Thuban (in Draco) was the closest bright star to the north celestial pole. When the Pyramids were built, the north star was Vega.
Sidereal and Synodic time: |
My Very Educated Mother Showed Us Nine Planets
Facts about PlutoIn Roman mythology, Pluto is the god of the underworld. The planet received this name perhaps because it’s so far from the Sun that it is in eternal darkness. http://www.backtowild.com/2007/09/ |
equator/rotation of the sun -
http://www.physicsforums.com/archive/index.php/t-216968.html |
Moon
The Moon is tidally locked to the Earth, meaning that one side always faces us (the nearside), whereas the farside is forever hidden from us. In addition, the Moon is illuminated on one side by the Sun, the other side is dark (night).
Which parts are illuminated (daytime) and which parts we see from the Earth are determined by the Moon's orbit around the Earth, what is called the phase of the Moon (click here for the current phase of the Moon). As the Moon moves counterclockwise around the Earth, the daylight side becomes more and more visible (i.e. we say the Moon is `waxing'). After full Moon is reached we begi n to see more and more of the nighttime side (i.e. we say the Moon is `waning'). This whole monthly sequence is called the phases of the Moon.
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Moon-rotation
http://www.mythicalireland.com/astronomy/moonmovements/moonpath.html |
The Real Romance in the StarsBy Richard DawkinsArticle in The Independent December 1995
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"In the space of one hundred and seventy-six years the Lower Mississippi has shortened itself two hundred and forty-two miles. Therefore ... in the Old Oolitic Silurian Period the Lower Mississippi River was upward of one million three hundred thousand miles long... seven hundred and forty-two years from now the Lower Mississippi will be only a mile and three-quarters long... There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact." Mark Twain |
The Flower of Life (commonly abbreviated as FOL) is the modern name given to a geometrical figure composed of multiple evenly-spaced, overlapping circles, that are arranged so that they form a flower-like pattern with a sixfold symmetry like a hexagon. The center of each circle is on the circumference of six surrounding circles of the same diameter. The earliest known example of the Flower of Life symbol dates to at least 400AD, and is possibly much older than that.[1] Throughout human history, philosophers, artists, and architects around the world have known the FOL for its perfect form, proportion, and harmony. It is considered by some pagans to be a symbol of sacred geometry, said to contain ancient, religious value depicting the fundamental forms of space and time.[2][3][4][5] In this (pagan) sense, it is a visual expression of the connections life weaves through all sentient beings, believed to contain a type of Akashic Record of basic information of all living things.[6] There are many spiritual beliefs associated with the FOL; for example, depictions of the five Platonic Solids are found within the symbol of Metatron's Cube, which may be derived from the FOL pattern. These platonic solids are geometrical forms which are said to act as a template from which all life springs. Another notable example of that which may be derived from the FOL is the Tree of Life[citation needed]. This has been an important symbol of sacred geometry for many people from various religious backgrounds. Particularly, the teachings of the Kabbalah have dealt intricately with the Tree of Life[citation needed]. http://en.wikipedia.org/wiki/Flower_of_Life
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Tree of Life
The symbol of the Tree of Life may be derived from the Flower of Life. The Tree of Life is a mystical concept, a metaphor for common descent, and a motif in various world theologies and philosophies.[47] This mystical concept has historically been adopted by some Christians, Jews, Hermeticists, and pagans.[48] Along with the Seed of Life it is believed to be part of the geometry that parallels the cycle of the fruit tree. This relationship is implied when these two forms are superimposed upon each other.[26] The Tree of Life is most widely recognized as a mystical concept within the Kabbalah, which is used to understand the nature of God and the manner in which He created the world ex nihilo (out of nothing). The Kabbalists developed this concept into a full model of reality, using the tree to depict a "map" of creation. The tree of life has been called the "cosmology" of the Kabbalah.[48] Some believe the Tree of Life of Kabbalah corresponds to the Tree of Life mentioned in Genesis 2:9.[4 |
Electromagnetic spectrumThe electromagnetic (EM) spectrum is the range of all possible electromagnetic radiation frequencies.[1] The "electromagnetic spectrum" (usually just spectrum) of an object is the characteristic distribution of electromagnetic radiation from that particular object. The electromagnetic spectrum extends from below the frequencies used for modern radio (at the long-wavelength end) through gamma radiation (at the short-wavelength end), covering wavelengths from thousands of kilometres down to a fraction the size of an atom. It is thought that the short wavelength limit is in the vicinity of the Planck length, and the long wavelength limit is the size of the universe itself (see physical cosmology), although in principle the spectrum is infinite and continuous.
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Curitiba
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HistoryMariners and explorers for most of history struggled to determine precise longitude. Latitude was calculated by observing with quadrant or astrolabe the inclination of the sun or of charted stars, but longitude presented no such manifest means of study. Amerigo Vespucci was perhaps the first to proffer a solution, after devoting a great deal of time and energy studying the problem during his sojourns in the New World.
By comparing the relative positions of the moon and Mars with their anticipated positions, Vespucci was able to crudely deduce his longitude. But this method had several limitations: First, it required the occurrence of a specific astronomical event (in this case, Mars passing through the same right ascension as the moon), and the observer needed to anticipate this event via an astronomical almanac. One needed also to know the precise time, which was difficult to ascertain in foreign lands. Finally, it required a stable viewing platform, rendering the technique useless on the rolling deck of a ship at sea. Unlike latitude, which has the equator as a natural starting position, there is no natural starting position for longitude. Therefore, a reference meridian had to be chosen. While British cartographers had long used the Greenwich meridian in London, other references were used elsewhere, including: El Hierro, Rome, Copenhagen, Jerusalem, Saint Petersburg, Pisa, Paris, Philadelphia, and Washington. In 1884, the International Meridian Conference adopted the Greenwich meridian as the universal prime meridian or zero point of longitude. |
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http://en.wikipedia.org/wiki/Longitude |
Position of the observerThe term conjunction primarily refers to a phenomenon defined only for the position of the observer, not just to a celestial relationship. However, e.g. for moon and sun observed from the earth, conjunction as a classifying term may apply both to the positions of conjunction (both sun and moon observed jointly in one direction or with similar ecliptical longitude) and to opposition (both sun and moon observed separately in opposite directions or with ecliptical longitude 180 degrees apart). Superior and inferiorAs seen from a planet that is superior, if an inferior planet is on the opposite side of the Sun, it is in superior conjunction with the Sun. An inferior conjunction occurs when the two planets lie in a line on the same side of the Sun. In an inferior conjunction, the superior planet is "in opposition" to the Sun as seen from the inferior planet. The terms "inferior conjunction" and "superior conjunction" are used in particular for the planets Mercury and Venus, which are inferior planets as seen from the Earth. However, this definition can be applied to any pair of planets, as seen from the one further from the Sun. A planet (or asteroid or comet) is simply said to be in conjunction, when it is in conjunction with the Sun, as seen from the Earth. The Moon is in conjunction with the Sun at New Moon (or rather Dark Moon). "Quasi-conjunctions" are also possible; in this scenario, a planet in retrograde motion — always either Mercury or Venus — will "drop back" in right ascension until it almost allows another planet to overtake it, but then the former planet will resume its forward motion and thereafter appear to draw away from it again. This will occur in the morning sky, before dawn; or the reverse may happen in the evening sky after dusk, with Mercury or Venus entering retrograde motion just as it is about to overtake another planet (often Mercury and Venus are both of the planets involved, and when this situation arises they may remain in very close visual proximity for several days or even longer). The quasi-conjunction is reckoned as occurring at the time the distance in right ascension between the two planets is smallest, even though, when declination is taken into account, they may appear closer together shortly before or after this. http://en.wikipedia.org/wiki/Conjunction_(astronomy) |
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Aphrodite
http://web.tampabay.rr.com/bmerkey/examples/fake-position-fixed.html
This has been a demonstration of faking fixed positioning with CSS for Internet Explorer without scripts. Back to CSS buttons