Why does the sun total eclipse occur?
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What is an eclipse of the Sun? What causes eclipses and why? How often do eclipses happen and when is the next eclipse of the Sun? You'll learn the answers to these questions and more in MrEclipse's primer on solar eclipses. Before we find more about the eclipses of the Sun, we need to first talk about the Moon. \n\nThe Moon is a cold, rocky body about 2,160 miles (3,476 km) in diameter. It has no light of its own but shines by sunlight reflected from its surface. The Moon orbits Earth about once every 29 and a half days. As it circles our planet, the changing position of the Moon with respect to the Sun causes our natural satellite to cycle through a series of phases: \n\nNew, New Crescent, First Quarter, Waxing Gibbous, Full, \nWaning Gibbous, Last Quarter, Old Crescent and back to New again.\n\n\n\nPhases of theMoon. \nThe phase known as New Moon can not actually be seen because the illuminated side of the Moon is then pointed away from Earth. The rest of the phases are familiar to all of us as the Moon cycles through them month after month. Did you realize that the word month is derived from the Moon's 29.5 day period? \n\nTo many early civilizations, the Moon's monthly cycle was an important tool for measuring the passage of time. In fact many calendars are synchronized to the phases of the Moon. The Hebrew, Muslem and Chinese calendars are all lunar calendars. The New Moon phase is uniquely recognized as the beginning of each calendar month just as it is the beginning on the Moon's monthly cycle. When the Moon is New, it rises and sets with the Sun because it lies very close to the Sun in the sky. Although we cannot see the Moon during New Moon phase, it has a very special significance with regard to eclipses. \n\n\n\nBasic Geometry of the Sun, Moon and Earth During an Eclipse of the Sun \nAn eclipse of the Sun (or solar eclipse) can only occur at New Moon when the Moon passes between Earth and Sun. If the Moon's shadow happens to fall upon Earth's surface at that time, we see some portion of the Sun's disk covered or 'eclipsed' by the Moon. Since New Moon occurs every 29 1/2 days, you might think that we should have a solar eclipse about once a month. Unfortunately, this doesn't happen because the Moon's orbit around Earth is tilted 5 degrees to Earth's orbit around the Sun. As a result, the Moon's shadow usually misses Earth as it passes above or below our planet at New Moon. At least twice a year, the geometry lines up just right so that some part of the Moon's shadow falls on Earth's surface and an eclipse of the Sun is seen from that region. \n\nThe Moon's shadow actually has two parts: \n\nPenumbra - Faint outer shadow; partial eclipses are seen from within this shadow. \n\nUmbra- Dark inner shadow; total eclipses are seen from within this shadow. \n\nWhen only the Moon's penumbral shadow strikes Earth, we see a partial eclipse of the Sun from that region. Partial eclipses are dangerous to look at because the un-eclipsed part of the Sun is still very bright. You must use special filters or a home-made pinhole projector to safely watch a partial eclipse of the Sun (see: Eclipses & Eye Safety). \n\nHowever, if the Moon's dark umbral shadow sweeps across Earth's surface, then a total eclipse of the Sun is seen (see figure below). The track of the Moon's shadow across Earth's surface is called the Path of Totality. It is typically 10,000 miles long but only 100 miles or so wide. In order to see the Sun totally eclipsed by the Moon, you must be in the path of totality. \n\n\n\nTotal Solar Eclipse and the Path of Totality \nThe total phase of a solar eclipse is very brief. It rarely lasts more than several minutes. Nevertheless, it is considered to be one of the most awe inspiring spectacles in all of nature. The sky takes on an eerie twilight as the Sun's bright face is replaced by the black disk of the Moon. Surrounding the Moon
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The lunar plane (the imaginary circle around the earth in which the moon revolves) is not in line with earth's view of the sun, hence solar eclipses, especially total solar eclipses, are rare events.\n\nBoth types of eclipses have comparative frequencies, but you're more likely to be able to see a lunar eclipse. The reason is, the earth's shadow is so much larger than the moon, and amost anyone on the night side of the earth will be able to see the lunar eclipse.\n\nCompare this to the shadow of the moon, which is really small when it falls on the earth, so only a limited number of people in a small area can see it.
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it is due to the rotaion of the Earth with respect to Sun , \n\nit is visible from east first  not rising , \n\nthe light rays emerges form east.
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There are many reasons.\nHere are a couple:\n\nThe temperature,\nThe matter that the sun is comprised of\nCheck out http://science.howstuffworks.com/sun.htm
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I would assume that a eclipse of the sun, not a lunar eclipse affect the magnetic field of the earth a little bit, for a simple reason. The earths magnetic field is deformed by the solar wind, a constant stream of charged particles from the sun. Now if we have a solar eclipse it means that the moon is between the sun and the earth, and by that shielding some of the solar wind. But as the moon is much smaller then the earth this effect is probably not very large.
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For the most part, it depends on where you are in comparison to the eclipse.  Also, the alignment of the the sun, moon, and earth need to be within a certain amount to create a partial eclipse or a total eclipse.  This is what I've read...I still might be wrong.
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You mean the moon and the sun, which is true\nsometimes, but there are also eclipses where\nthe moon is smaller than the sun, so a small\nring of light is left uncovered (called an annular\neclipse)...\n\nBy a stroke of amazing coincidence, both the\nmoon and the sun are approx 108 times as\nfar from the earth as their diameter, so they\nappear the same size in the sky... 108 is a\nmystic number in spirituality, so I doubt if this\nis really a coincidence!
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First, one can't see the entire Moon from Earth; only one side of the Moon faces the Earth directly, this is the near side of the Moon. The far side of the Moon (sometimes innacurately called the dark side of the Moon) always faces away. this behavior is due to tidal lock: http://en.wikipedia.org/wiki/Tidal_lock .\nSecondly, one may not see the near side of the Moon due to atmospheric phenomena. This is trivial.\nThirdly, one may not see the entire near side of the Moon due to the orientation of the Sun with respect to the Moon. The Sun may be shining on some other side of the Moon with respect to our viewing angle on Earth and thus we only see a fraction of the near side lit up by sunlight. To see this graphically, look at the diagram of Moon phases on http://en.wikipedia.org/wiki/Phases_of_the_moon .\nFinally, one may not see the Moon due to a lunar or solar eclipse. This is caused by the Earth's shadow falling on the Moon in the first case and by the Moon blocking the sunlight from falling on the Earth in your region in the second case. These both occur when the Moon, Earth and Sun are approximately in a line. See http://en.wikipedia.org/wiki/Eclipses for diagrams.\nAlso, the Moon may not be visible because it simply has not risen yet. ;)
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The width of the track of a central eclipse varies according to the relative apparent diameters of the Sun and Moon. In the most favourable circumstances, when a total eclipse occurs very close to perigee, the track can be over 250 km wide and the duration of totality may be over 7 minutes. Outside of the central track, a partial eclipse can usually be seen over a much larger area of the Earth.  Have a look at http://en.wikipedia.org/wiki/Solar_eclipse for a good explanation and diagram
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There are three types of Lunar Eclipse. Penumbral Lunar Eclipse,Partial Lunar Eclipse, and Total Lunar Eclipse.\n\nPenumbral Lunar Eclipse\nThe Moon passes through Earth's penumbral shadow. These events are of only academic interest since they are subtle and quite difficult to observe\nPartial Lunar Eclipse\nA portion of the Moon passes through Earth's umbral shadow. These events are easy to see, even with the unaided eye\nTotal Lunar Eclipse\nThe entire Moon passes through Earth's umbral shadow.\nThese events are quite striking for the vibrant range of colors the Moon can take on during the total phase(due to refracting light thru the earths atmosphere)\nIf the Moon orbits Earth every 29.5 days and lunar eclipses only occur at Full Moon, then why don't we have an eclipse once a month during Full Moon?.The Moon's orbit around Earth is actually tipped about 5 degrees to Earth's orbit around the Sun. This means that the Moon spends most of the time either above or below the plane of Earth's orbit. And the plane of Earth's orbit around the Sun is important because Earth's shadows lie exactly in the same plane. During Full Moon,the moon usually passes above or below Earth's shadows and misses them entirely. No eclipse takes place. But two to four times each year, the Moon passes through some portion of the Earth's penumbral or umbral shadows and one of the above three types of eclipses occurs.
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Earth's shadow, it is called a lunar eclipse. \n\nWhen the Earth crosses between the Moon and the Sun in exact alignment, a total lunar eclipse occurs.
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This question could be very easily answered by looking up solar eclipses somewhere such as Wikipedia. \n\nA solar eclipse happens when the moon passes between the Earth and Sun, causing people on Earth to be completely or partially unable to see the sun, because the moon is in the way. This is able to happen in spite of the fact that the moon is much smaller than the sun, because while the sun is about 400 times bigger than the moon, it is also 400 times farther away from the Earth than the moon is. \n\nThe reason that a solar eclipse can only happen during the new moon is that the new moon phase is the only time when the moon is in between the Earth and Sun at all.
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full moon.  a lunar eclipse occurs when the earth blocks the light from the sun, so the earth is positioned between the sun and moon - the full moon phase.
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In the morning/evening the sun rays are falling obliquely on to the earth, \nthereby passing through a thicker layer of the atmospheric air because of which (oblique incidence) a lot of its blue component is scattered off \n\nIts 1/lambda^4 scattering - smaller the lambda, larger is the energy scattered off/lost as compared to shorter path transversed during the day time \n\n[This is a standard class XII Physics question]
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it occurs when solar radiation from the sun interacts with the magnetic field around the Earth (its strongest around the poles..so thats why theres a northern..AND southern lights...and no "Middle" lights lol)\n\ni can't wait to see it some day
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You know that when it's daytime for you, someone on the other side of Earth is experiencing night time - the Sun lights up half of the earth at any given time.  The same is true for the Moon - it is always half lit up by the Sun and half dark.  But we don't always see the lit up side.  Sometimes we do, like tonight (a Full Moon).  But other times we "see" the dark half (a New Moon) (you can't really see the dark half because it's dark!), and sometimes we see a little bit of both (First Quarter Moon, for example).  \n\nWe see different parts of the lit up side and the dark side because the Moon orbits Earth about once every month.  Right now, if you were to see the Sun, Earth, and Moon from high above Earth's north pole, the three would be almost lined up: Sun, then Earth, then Moon.  If they were *perfectly* lined up then there would be a lunar eclipse, but that only happens a couple times a year, if that.  Next week, as the Moon goes around Earth, the Sun, Earth, and Moon will make a right angle and not a straight line.  That's when we see a Third Quarter Moon - only the left half of the Moon will be visible as seen from Earth.  Another week and the Moon will be almost between the Sun and Earth, so the dark side of the Moon will be facing Earth - what we call New Moon.  (If the Moon came exactly between the Sun and Earth we would have a solar eclipse, but just like lunar eclipses they are very rare).\n\nThere is a huge difference between a lunar eclipse and a new moon - apparently several of the people who answered above me don't know that!
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the answer is actually no, i say this as i assumen you a refering to a total eclipse. this is when the moon covers the sun and makes everything go blck. there are however partial eclipses(eclipse) on all planets as this is when some object(moon or planet) blocks some of the sunlight from the planet or moon. \n\nwe have an odd situatin when the distance from the sun and the moon to earch exactly match the size of the rays hit by the earth from the sun. that means that the moon as big as it is is just the correct disstance to cover the suns exactly in a total eclipse.\n\nthe same thigs happen with other planets such as venus. when you see it infront of the sun its causeing and eclipse, its blocking some light from the sun, however its so small and so faraway that you cant notice it.\n\nand if you mean do all the planets align with each other the answer is yes. it dont happen very often and i cant tell you when ti happened last or when it will happen, but if you think of it like marbles in a row, and you have your head behind the furthiest you cant see the first or anyothers sept the one your behind. the palants do that.