Free Essay

Solar and Lunar Eclipse

In:

Submitted By allviaferreira23
Words 1749
Pages 7
Lunar eclipse
From Wikipedia, the free encyclopedia
For other uses, see Lunar eclipse (disambiguation).

A lunar eclipse occurs when the moon passes behind the earth so that the earth blocks the sun's rays from striking the moon. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur the night of a full moon. The type and length of an eclipse depend upon the Moon's location relative to its orbital nodes. Themost recent total lunar eclipse occurred on June 15, 2011; it was a central eclipse, visible over Europe and south America after sunset, over Africa and most of Asia, and Australia before sunrise. It was also the longest and darkest lunar eclipse of the century, lasting 100 minutes. The previous total lunar eclipse occurred on December 21, 2010, at 08:17 UTC.[
Unlike a solar eclipse, which can only be viewed from a certain relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of the Earth. A lunar eclipse lasts for a few hours, whereas a total solar eclipse lasts for only a few minutes at any given place.

Types of lunar eclipse
The shadow of the Earth can be divided into two distinctive parts: the umbra and penumbra. Within the umbra, there is no direct solar radiation. However, as a result of the Sun’s large angular size, solar illumination is only partially blocked in the outer portion of the Earth’s shadow, which is given the name penumbra. Apenumbral eclipse occurs when the Moon passes through the Earth’s penumbra. The penumbra causes a subtle darkening of the Moon's surface. A special type of penumbral eclipse is a total penumbral eclipse, during which the Moon lies exclusively within the Earth’s penumbra. Total penumbral eclipses are rare, and when these occur, that portion of the Moon which is closest to the umbra can appear somewhat darker than the rest of the Moon.
A partial lunar eclipse occurs when only a portion of the Moon enters the umbra. When the Moon travels completely into the Earth’s umbra, one observes atotal lunar eclipse. The Moon’s speed through the shadow is about one kilometer per second (2,300 mph), and totality may last up to nearly 107 minutes. Nevertheless, the total time between the Moon’s first and last contact with the shadow is much longer, and could last up to 4 hours.[2] The relative distance of the Moon from the Earth at the time of an eclipse can affect the eclipse’s duration. In particular, when the Moon is near its apogee, the farthest point from the Earth in its orbit, its orbital speed is the slowest. The diameter of the umbra does not decrease appreciably within the changes in the orbital distance of the moon. Thus, a totally eclipsed Moon occurring near apogee will lengthen the duration of totality.
Eclipse cycles
See also: Saros cycle and Eclipse cycle
Every year there are at least two lunar eclipses, although total lunar eclipses are significantly less common. If one knows the date and time of an eclipse, it is possible to predict the occurrence of other eclipses using an eclipse cycle like the Saros cycle.

Solar eclipse
From Wikipedia, the free encyclopedia

Photo of 1999 total eclipse
This article is about the astronomical phenomenon. For the video game, see Solar Eclipse (video game).
As seen from the Earth, a solar eclipse occurs when the Moon passes between the Sun and the Earth, and the Moon fully or partially covers the Sun as viewed from a location on Earth. This can happen only during a new moon, when the Sun and Moon are in conjunction as seen from Earth. At least two, and up to five, solar eclipses occur each year; no more than two can be total eclipses.[1][2] Total solar eclipses are nevertheless rare at any particular location because totality exists only along a narrow path on the Earth's surface traced by the Moon's umbra.
Some people, sometimes referred to as "eclipse chasers" or "umbraphiles",[3] [4] will travel to remote locations to observe or witness a predicted central solar eclipse (seeTypes below). The solar eclipse of August 11, 1999, in Europe helped to increase public awareness of the phenomenon[citation needed], which apparently led to an unusually large number of journeys made specifically to witness the annular solar eclipse of October 3, 2005, and of March 29, 2006.
The last total solar eclipse was the solar eclipse of July 11, 2010; the next will be the solar eclipse of November 13, 2012. The recent solar eclipse of June 1, 2011, was a partial eclipse (see Types below); the next partial eclipse will occur on July 1, 2011.
A total solar eclipse is a natural phenomenon. Nevertheless, in ancient times, and in some cultures today, solar eclipses have been attributed to supernatural causes or regarded as bad omens. A total solar eclipse can be frightening to people who are unaware of their astronomical explanation, as the Sun seems to disappear during the day and the sky darkens in a matter of minutes.

Types

There are four types of solar eclipses:
 A total eclipse occurs when the dark silhouette of the Moon completely obscures the intensely bright light of the Sun, allowing the much fainter solar corona to be visible. During any one eclipse, totality occurs at best only in a narrow track on the surface of the Earth.
 An annular eclipse occurs when the Sun and Moon are exactly in line, but the apparent size of the Moon is smaller than that of the Sun. Hence the Sun appears as a very bright ring, or annulus, surrounding the outline of the Moon.
 A hybrid eclipse (also called annular/total eclipse) shifts between a total and annular eclipse. At some points on the surface of the Earth it appears as a total eclipse, whereas at others it appears as annular. Hybrid eclipses are comparatively rare.
 A partial eclipse occurs when the Sun and Moon are not exactly in line and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra passes above the Earth's polar regions and never intersects the Earth's surface.
The Sun's distance from the Earth is about 400 times the Moon's distance, and the Sun's diameter is about 400 times the Moon's diameter. Because these ratios are approximately the same, the Sun and the Moon as seen from Earth appear to be approximately the same size: about 0.5 degree of arc in angular measure.

Occurrence and cycles

Total solar eclipses are rare events. Although they occur somewhere on Earth every 18 months on average,[19] it has been estimated that they recur at any given place only once every 370 years, on average. The total eclipse only lasts for a few minutes at that location, as the Moon's umbra moves eastward at over 1700 km/h. Totality can never last more than 7 min 31 s, and is usually much shorter: during each millennium there are typically fewer than 10 total solar eclipses exceeding 7 minutes. The last time this happened was June 30, 1973 (7 min 3 sec). Observers aboard a Concorde aircraft were able to stretch totality to about 74 minutes by flying along the path of the Moon's umbra. The next eclipse exceeding seven minutes in duration will not occur until June 25, 2150. The longest total solar eclipse during the 8,000-year period from 3000 BC to 5000 AD will occur on July 16, 2186, when totality will last 7 min 29 s.[20]For comparison, the longest eclipse of the 20th century occurred on June 20, 1955 and lasted 7 min 8 sec.
If the date and time of any solar eclipse are known, it is possible to predict other eclipses using eclipse cycles. Two such cycles are the Saros and the Inex. The Saros cycle is probably the best known and one of the most accurate eclipse cycles. The Inex cycle is itself a poor cycle, but it is very convenient in the classification of eclipse cycles. After a Saros cycle finishes, a new Saros cycle begins one Inex later, hence its name: in-ex. A Saros cycle lasts 6,585.3 days (a little over 18 years), which means that after this period a practically identical eclipse will occur. The most notable difference will be a shift of 120° in longitude (due to the 0.3 days) and a little in latitude. A Saros series always starts with a partial eclipse near one of Earth's polar regions, then shifts over the globe through a series of annular or total eclipses, and ends at the opposite polar region. A Saros (series) lasts 1226 to 1550 years and 69 to 87 eclipses, with about 40 to 60 central
Frequency per year
Solar eclipses can occur 2 to 5 times per year, at least once per eclipse season. Since the Gregorian calendar was instituted in 1582, years that have had five solar eclipses were 1693, 1758, 1805, 1823, 1870, and 1935. The next occurrence will be 2206.[2

Historical eclipses
Historical eclipses are a very valuable resource for historians, in that they allow a few historical events to be dated precisely, from which other dates and a society's calendar may be deduced. Aryabhata (476–550) concluded the Heliocentric theory in solar eclipse. A solar eclipse of June 15, 763 BC mentioned in an Assyrian text is important for the Chronology of the Ancient Orient. Also known as the eclipse of Bur Sagale, it is the earliest solar eclipse mentioned in historical sources that has been identified successfully. Perhaps the earliest still-unproven claim is that of archaeologist Bruce Masse asserting on the basis of several ancient flood myths, which mention a total solar eclipse, he links an eclipse that occurred May 10, 2807 BC with a possible meteor impact in the Indian Ocean.[24] There have been other claims to date earlier eclipses, notably that of Mursili II (likely 1312 BC), in Babylonia, and also in China, during the Fifth Year (2084 BC) of the regime of Emperor Zhong Kang of Xiadynasty, but these are highly disputed and rely on much supposition

Similar Documents

Premium Essay

Moon Research Paper

...What is the brightest and most noticeable object in our sky? If someone had asked you this question; your answer would be the Sun. Now your answer to the question is correct but, aside from the Sun, the Moon is also the brightest and most noticeable object in our sky. The Moon is Earth’s only natural satellite. The Moon is a roughly spherical, rocky body that orbits the Earth and its diameter is about one-fourth Earth’s diameter (“Moon”). This object does more than orbits the Earth and light up the night sky. The Moon goes through a lunar phase, cause eclipses, and has a strong effect on Earth’s tides, but before the Moon could do this it had to be formed. How did our Moon form? There is a strong hypothesis suggests that it formed as the result...

Words: 1460 - Pages: 6

Free Essay

Honors Physics

...Astronomy Project A Lunar Eclipse is an eclipse in which the full moon passes partially or wholly through the umbra of the earth's shadow (Merriam-Webster, 2012). When this happens, the moon appears darker as it passes into the earth's shadow. One thing that I found interesting is that there are different types of eclipses. When I first read more information on the lunar eclipse I was confused about what those differences are. I found out that during the five thousand year period from 2000 BCE through 3000 CE, there are 7,718 eclipses (both partial and total) of the Moon (Espenak). The two types of eclipses are the lunar eclipse and the solar eclipse. A solar eclipse can only be viewed from a small area of the world but a lunar eclipse may be viewed from anywhere on the night side of the Earth. According to Keith Cooley, there are three different types of lunar eclipses. They are as follows: * Partial Lunar Eclipse - A portion of the Moon passes through the Earth's umbral shadow. These events are easy to see, even with the unaided eye. * Penumbral Lunar Eclipse - The Moon passes through the Earth's penumbral shadow. These events are subtle and quite difficult if not impossible to observe. During a penumbral eclipse the moons light is dimmed but does not go dark due to the fact that the penumbral shadow is not dark enough to black out the sun's light. A penumbral eclipse is sometimes referred to as an appulse eclipse. * Total Lunar Eclipse - The entire Moon passes...

Words: 835 - Pages: 4

Free Essay

Solar Eclips

...kilometers per hour. On eclipse-viewing expeditions, this phenomenon is frequently accompanied by a marriage proposal. The beautiful symmetry of a total solar eclipse happens because—by pure chance—the sun is 400 times larger than the moon but is also 400 times farther from Earth, making the two bodies appear the exact same size in the sky. In case you were thinking about relocating: Earth is the only place in the solar system where that happens. The Chinese word for solar eclipse is shih, meaning “to eat.” In ancient China people traditionally beat drums and banged on pots to scare off the “heavenly dog” believed to be devouring the sun. Tidal friction, which causes that lengthening of the day, is also making the moon drift away. In about 600 million years it will appear too small to cover the sun, and there will be no more total solar eclipses. In ancient times, people thought an eclipse was a sign that the gods were angry or that bad things were about to happen. Medieval folk believed that sex during an eclipse would result in ugly demon-filled children Europeans in the Middle Ages thought that you should never get it on during a lunar eclipse, because any “moon children” would be born with ugly demons inside them. Then you’d have to pay for their food and shelter, when all they’re going to be good for is being burned at the stake. A modern superstition also has it that a pregnant woman shouldn’t touch her belly during a lunar eclipse. Doing so will cause...

Words: 298 - Pages: 2

Premium Essay

Astronomy Test Review

...east at 9pm tonight? When will it rise tomorrow night? f. 4 minutes earlier -8:56 pm – the next sidereal day 7. What does the word sidereal mean? what is a sidereal day? g. Anything relative to the stars – The time is takes for a start to come up in the same position in the sky the next day (approx. 23 hours 56 minutes) 8. Are we closer to the sun in winter or in summer? h. Winter 9. What is the ecliptic? What are the two ways of using it to describe Earth or the Sun seen from the Earth. i. The path of the sun’s motion as seen from the Earth throughout the year j. It’s the plane of Earth’s orbit is space 10. Define heliocentric and geocentric. k. heliocentric- Sun was center of the solar system – proposed by Copernicus l. geocentric – earth-centered model, idea that moon, sun, stars, revolve around earth 11. What is the celestial sphere? What are the major lines (circles) and important points on it? m. it’s as if we expanded the earth’s equator and north/south poles out into space. n. Celestial equator, North Celestial Pole, South Celestial Pole 12. When is the Sun...

Words: 704 - Pages: 3

Premium Essay

Moon Info

...the Solar System. It is the largest natural satellite of a planet in the Solar System relative to the size of its primary, a quarter the diameter of Earth and 1⁄81 its mass . The Moon is the second densest satellite after Io. It is in synchronous rotation with Earth, always showing the same face; the near side is marked with dark volcanic maria among the bright ancient crustal highlands and prominent impact craters. It is the brightest object in the sky after the Sun, although its surface is actually very dark, with a similar reflectance to coal. Its prominence in the sky and its regular cycle of phases have since ancient times made the Moon an important cultural influence on language, calendars, art and mythology. The Moon's gravitational influence produces the ocean tides and the minute lengthening of the day. The Moon's current orbital distance, about thirty times the diameter of the Earth, causes it to appear almost the same size in the sky as the Sun, allowing it to cover the Sun nearly precisely in total solar eclipses. The Moon is the only celestial body on which humans have landed. While the Soviet Union's Luna programme was the first to reach the Moon with unmanned spacecraft in 1959, the United States' NASA Apollo program achieved the only manned missions to date, beginning with the first manned lunar orbiting mission by Apollo 8 in 1968, and six manned lunar landings between 1969 and 1972—the first being Apollo 11. These missions returned over 380 kg of lunar rocks...

Words: 2154 - Pages: 9

Premium Essay

Astronomy

...Celestial Pole on the horizon? A the Arctic Circle B the equator C the North Pole D the South Pole E there are many latitudes where this occurs 5. Galileo's observations of the phases of Venus helped convince him that A the Moon goes around the Earth B the Sun goes around the Earth C Venus goes around the Earth D Venus goes around the Sun E Ptolemy's model of the solar system was correct 6. The angular distance of an object in the sky, above the observer's horizon is called its A azimuth B altitude C declination D latitude E right ascension 7. The ecliptic is A the line passing from north to south directly overhead B the orbit of the Moon C the path of a star in the sky D the path of the Earth's north pole in the sky E the path of the Sun in the sky 8. Which of the following statements about the Copernican solar system model is correct? A it did away with the need for epicycles B it had the Earth motionless C it provided a physical explanation of why the planets moved D it used uniform circular motion E it was the first time we know of that anyone regarded the Sun as the center of the solar system 9. Suppose you are a space shuttle astronaut taking a space...

Words: 2126 - Pages: 9

Premium Essay

Pt1420 Unit 9 Lab Report

...1) The phase of the Moon during a total solar eclipse is a new moon. In a solar eclipse, the Moon is in between the Sun and the Earth. The Moon blocks some sunlight creating a the Earth to become dark for a few minutes at specific locations. The phase of the Moon during a total lunar eclipse is a full moon. In a lunar eclipse, the Earth is in between the Sun and the Moon. The Earth blocks the Moon from the Sun. The Earth casts its shadow on the Moon, giving it a red color. 2) Earth’s core is spilt into two sections, the outer core and inner core. The liquid outer core is made up of iron, nickel, and perhaps sulfur. The solid inner core is made of iron and nickel. The mantle is made up of silicates. We know this because of seismic waves that are generated by earthquakes. The seismic waves move at a certain speed depending on the material which they travel through....

Words: 558 - Pages: 3

Premium Essay

Structure of the Universe

...Earth-centered * Solar system: the Sun and all the objects that orbits it * Our solar system formed 4.5 billion years ago * Galaxy: great island of stars in space, having from a few hundred million to a trillion or more stars * Milky Way Galaxy contains more than 100 billion stars; our Milky Way is in the Local Group * Galaxy cluster: collection of galaxies bound together by gravity. Small collections (up to a few dozen) are generally called groups, while larger collections are called clusters * Supercluster: gigantic region of space where many individual galaxies and many groups and clusters of galaxies are packed more closely together than elsewhere in the universe * Universe (cosmos): the sum total of all mater and energy * Observable Universe: the portion of the entire universe that can be seen from Earth * Universe is expanding, Big Bang occurred 14 billion years ago * Planet: moderately sized object that orbits a star and shines primarily by reflecting light from its star; an object is a planet if it (1) orbits a star, (2) is large enough for its own gravity to make it round, and (3) has cleared most other objects from its orbital path * Dwarf planet: object that meets the first two criteria but not the third, like Pluto * Moon (or satellite): an object that orbits a planet * Asteroid: a relatively small and rocky object that orbits a star * Comet: a relatively small and ice-rich object that orbits a star * Small solar system...

Words: 6164 - Pages: 25

Premium Essay

Benjamin Banneker: A Brief Biography

...Benjamin Banneker Benjamin Banneker was born on November 9th, 1731 in Baltimore, Maryland. His father and mother were slaves that earned their freedom . He also had three younger sisters who loved to play with him even when he is busy. Benjamin was mostly self taught because he worked on a farm to help his dad with chores. Although he was self taught, he did go to a school once in awhile to acel his learning. At the age of twenty he built a working clock to help keep time around the farm. Benjamin eventually inherited the farm from his grandparents and he grew tobacco and sold it to make money. He was not only a farmer but an astronomer. One of the things he did in astronomy is calculated when the solar and lunar eclipses would appear in...

Words: 251 - Pages: 2

Free Essay

Stonehenge

...Stonehenge is not only the most famous stone circle in Britain, but also the best-known ancient monument in the World, with at least ½ a million visitors each year. Located on Salisbury Plain, north of Salisbury, England, it is famous for the debate, mystery, and speculation surrounding it. Stonehenge was not built all in one single step, but rather in four separate stages, dating from approximately 3100BC to 1500BC. The modern visitor to Stonehenge is viewing the ruins of the final phase of construction site. The monument itself consists of four concentric ranges of stones. The oldest part, called Stonehenge I, consists of little more than a circular ditch dug in the chalky soil of the Salisbury Plain, with the soil taken from the ditch piled up to make an enbankment about 6 ft tall. This part of the monument is about 320 ft across. Inside this large circle are the things that we normally think of as Stonhenge proper; circles of stones that once stood upright, and the most photogenic, the large horseshoe arrangements of standing stones at the center. These last, the so-called trillithons, consist of upright stones supporting horizontal lintels, and the largest of them weigh in around 45 tons. These massive stones have been placed in unison with these circles to create Stonehenge and along with that bring about the curiosity of why one would build such a structure as that of Stonehenge. The location of Stonehenge was not simply a coincidental happening, for the latitude is very...

Words: 1217 - Pages: 5

Premium Essay

Basics of Astronomy Outline

...SCI/151 Week 1 Assignment Basics of Astronomy Outline I. Our place in the universe A. The modern view of the universe 1. The Sun is a star in our solar system that generates heat and light to our planet, Earth through nuclear fusion. 2. Our Milky Way galaxy is an island of stars in space with hundreds of billions of stars like our Sun. 3. The Big Bang is a theory of when the universe started expanding about 14 billion years ago. 4. The phase “looking out in the universe is looking back in time,” refers to the light from other stars we see at night happened in 1913 because light takes time to travel through space. B. Where are we in the universe? 1. Earth’s place in the solar system is the third planet nearest to the Sun, a star. It is very small but the only dense planet with life forms. 2. The nearest stars to the Sun and compare the distance between the Sun and Earth a. The nearest star system is Alpha Centauri that is 4.4 light-years away. b. The distance between the Earth, and the Sun is 92,600,000 miles; it takes eight minutes for light from the Sun to reach Earth. 3. The Milky Way galaxy is about one hundred thousand light-years in diameter. 4. It is estimated that one hundred billion stars are in our galaxy. 5. The Earth is only four and one-half billion years of age in comparison to the universe is 14 billion. C. Motion in the universe 1. Earth orbits the Sun at 66,000 miles per hour that is equal to 107,000 kilometers per hour, which is one...

Words: 978 - Pages: 4

Premium Essay

How Did Ancient Civilization Use Astronomy

...Ancient civilizations used astronomy by studying the sky for centuries. When they did this, they recorded what they had seen. By doing this they could predict a lot of things such as lunar eclipses and solar eclipse. Because of all the information they had by studying the sky, they were able to make a calendar. It involved solar years and lunar months. Scientific studies have influenced the decisions of where people want to live. Scientists say that climate change has a lot to do with certain extreme weather events that have been happening lately. Climate change affects major storms such as hurricanes and typhoons. The storm that is most affected by it is tornadoes. Ever since these studies came out, people have been careful on where they want to buy their house....

Words: 610 - Pages: 3

Free Essay

Thee Moon

...Moon The Moon (Latin: Luna) is the Earth's only natural satellite.[e][f][8] Although not the largest natural satellite in the Solar System, it is, among the satellites of major planets, the largest relative to the size of the object it orbits (its primary) [g][h] and, after Jupiter's satellite Io, it is the second most dense satellite among those whose densities are known. The Moon is in synchronous rotation with Earth, always showing the same face with its near side marked by dark volcanic maria that fill between the bright ancient crustal highlands and the prominent impact craters. It is the most luminous object in the sky after the Sun. Although it appears a very bright white, its surface is actually dark, with a reflectance just slightly higher than that of worn asphalt. Its prominence in the sky and its regular cycle of phases have, since ancient times, made the Moon an important cultural influence on language, calendars, art, and mythology. The Moon's gravitational influence produces the ocean tides and the slight lengthening of the day. The Moon's current orbital distance is about thirty times the diameter of Earth, causing it to have an apparent size in the sky almost the same as that of the Sun. This allows the Moon to cover the Sun nearly precisely in total solar eclipse. This matching of apparent visual size is a coincidence. The Moon's linear distance from Earth is currently increasing at a rate of 3.82±0.07 cm per year, but this rate is not constant.[9] The Moon...

Words: 553 - Pages: 3

Free Essay

Basics of Astronomy Outline Answersheet

...|  | Please write your answers only excluding the original questions. | |1 |The sun is considered to be a star and is a hot ball of glowing gases. It is known as the heart of our solar system. | |2 |There are over 200 billion stars in the Milky Way. It is made up of the billions of stars as well as enough gas and dust to make a | | |billions more. The Milky Way is over 100,000 light years from one end to the other. | |3 |According to Reeves (1999), “Astronomers, believe that the universe began in a big bang roughly 14 billion years ago” (para. 5). They | | |believed that a bubble exploded suddenly and the birth of the universe began. Keep in mind this bubble was only about the size of a | | |pinhead.  | |4 |You are looking back in time because of the speed of light. Light moves 186,000 miles per second. An example of this would be like we see| | |the sun, eight minutes after the fact.  | |5 |The Earth is the 3rd planet from the Sun. Earth is where we live, and is the only planet that contains life. Earth is the only planet...

Words: 613 - Pages: 3

Premium Essay

Ancient Calendars

...be credited to a countless number of people who, over hundreds of years, spent their time straining their necks to look up at our sky. The sun is the center of our solar system, but that does not mean that it was always central to the beliefs...

Words: 1269 - Pages: 6