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Eclipses of the Sun and Moon. A solar eclipse occurs when the Moon passes between Earth and the (credit: © Merriam-Webster Inc.)

The passage of all or part of one celestial body into the shadow of another, the eclipsing body. Observers on Earth experience two major typeslunar eclipses and solar eclipseseach of which involves the Sun and the Moon. The type observed depends on whether Earth is the eclipsing body or the body in shadow. In a lunar eclipse the orbit of the Moon carries it through Earth's shadow. Observers see the full Moon dim considerably, but it remains faintly visible. In a solar eclipse the Moon is the eclipsing body, passing between Earth and the Sun while casting a traveling shadow across Earth's lighted surface. Observers along the shadow's path see a total or partial obscuring of the Sun's disk by the Moon's silhouette. The shadow cast by the eclipsing body consists of the central umbra, into which no direct sunlight penetrates (total eclipse), and the encircling penumbra, reached by light from only part of the Sun's disk (partial eclipse). Solar eclipses visible from different parts of Earth occur two to five times a year; one total solar eclipse occurs in most years. When Earth is closest to the Sun and the Moon farthest from Earth, the Moon's silhouette may fall entirely within the Sun's disk, with a ring of the disk visible around it (annular eclipse). Lunar eclipses occur twice in most years. Other kinds of eclipses include those of the Sun by Mercury or Venus (transits), of distant stars by planets or planetary satellites (occultations), and of stars by orbiting companion stars ( eclipsing variable star). Baily's beads.

For more information on eclipse, visit Britannica.com.

The occultation (obscuring) of one celestial body by another. Solar and lunar eclipses take place at syzygies of the Sun, Earth, and Moon, when the three bodies are in a line. At a solar eclipse, the Moon blocks the view of the Sun as seen from the Earth. At a lunar eclipse, the Earth's shadow falls on the Moon, darkening it, and can be seen from wherever on Earth the Moon is above the horizon.

Solar eclipses

A solar eclipse can be understood as an occultation of the Sun by the Moon or, equivalently, the Moon's shadow crossing the Earth's surface. The darkest part of the shadow, from which the Sun is entirely hidden, is the umbra (Fig. 1). The outer part of the shadow, from which part of the Sun can be seen, is the penumbra.

Circumstances of solar and lunar eclipses (not to scale).

Solar eclipses can be central, in which the Moon passes entirely onto the solar disk as seen from Earth, or partial, in which one side of the Sun always remains visible. Central eclipses can be total, in which case the Moon entirely covers the solar photosphere, making the corona visible for the period of totality, or annular, in which case the Moon's angular diameter is smaller than that of the Sun because of the positions of the Earth and Moon in their elliptical orbits. At an annular eclipse, a bright annulus of photospheric sunlight remains visible; it is normally thousands of times brighter than the corona, leaving the sky too blue for the corona to be seen.

The plane of the Moon's orbit is inclined by 5° to the plane of the Earth's orbit (the ecliptic), so the Moon's shadow commonly passes above or below the Earth each month at new moon. But two to five times each year, the Moon's shadow reaches the Earth, and a partial, annular, or total eclipse occurs. The Moon is approximately 400 times smaller than the Sun but is also approximately 400 times closer, so its angular diameter in the sky is about the same as the Sun's. Thus the Moon fits approximately exactly over the photosphere, making the phenomenon of a total eclipse especially beautiful.

The partial phases of a total eclipse visible from the path of totality last over an hour. In the minute or two before totality, shadow bands—low-contrast bands of light and dark caused by irregularities in the Earth's upper atmosphere—may be seen to race across the landscape. As the Moon barely covers the Sun, photospheric light shines through valleys on the edge of the Moon, making dots of light—Baily's beads—that are very bright in contrast to the background. The last Baily's bead gleams so brightly that it appears as a jewel on a ring, with the band made of the corona; this appearance is known as the diamond ring effect. It usually lasts for 5–10 s, and in the clearest skies for as long as 40 s.

During the diamond ring effect, the solar chromosphere becomes visible around the limb of the Moon, glowing pinkish because most of its radiation is in the form of emission lines of hydrogen, mostly the red hydrogen-alpha line. Its emission-line spectrum apparently flashes into view for a few seconds, and is called the flash spectrum. As the advancing limb of the Moon covers the chromosphere, the corona becomes fully visible (Fig. 2). Its shape is governed by the solar magnetic field; common are equatorial streamers and polar tufts. At the maximum of the solar activity cycle, so many streamers exist that the corona appears round when it is seen in projection, as viewed from Earth. At the minimum of the solar activity cycle, only a few streamers exist so that the corona appears more elongated in projection. See also Sun.

Total solar eclipse of February 26, 1998, observed from Aruba, Netherlands Antilles. Image is composited from several exposures in order to show the wide dynamic range of intensity of the corona and to bring out the structures of the streamers. (Jay M. Pasachoff and Wendy Carlos)

Totality lasts from an instant up through somewhat over 7 min. At its end, the phenomena repeat, including chromosphere, diamond ring, Baily's beads, shadow bands, and the partial phases.

The paths of the Sun and Moon in the sky intersect at two points, the ascending node and the descending node. Only when both the Sun and the Moon are near a node can an eclipse occur. Thus eclipse seasons take place each year, whenever the Sun is near enough to the node so that an eclipse is possible. Each eclipse season is 38 days long. Because the Sun's gravity causes the orientation of the Moon's elliptical orbit to change with an 18.6-year cycle, the nodes slide along the ecliptic and a cycle of two eclipse seasons—an eclipse year—has a period of 346.6 days, shorter than a solar year. See also Moon.

There must be at least one solar eclipse each eclipse season, so there are at least two each year. There may be as many as five solar eclipses in a calendar year, though most of these will be partial. Adding lunar eclipses (including penumbral lunar eclipses, which may not be noticeable), there may be seven eclipses in a year.

An important coincidence relates lunar months and eclipse years. A total of 223 lunar months (technically, synodic months, the period of the phases) takes 6585.32 days. A total of 19 eclipse years (passages of the Sun through the same node of the Moon's orbit) takes 6585.78 days, and 242 nodical months (passages of the Moon through the node) take 6585.36 days. Thus eclipses appear with this period of 18 years days (plus or minus a day, depending on leap years), a period known as the saros. Further, 239 periods of the variation of distance of the Moon from the Earth, the anomalistic month, is 6585.54 days, so the relative angular sizes of the Sun and Moon are about the same at this interval. As a result of the saros, almost identical eclipses recur every 18 years days. The significance of the day is that the Earth rotates one-third of the way around, and the eclipse path is shifted on the Earth's surface.

Even with advances in space technology, total solar eclipses are the best way of seeing the lower corona. Related eclipse studies include use of the advancing edge of the Moon to provide high spatial resolution for radio observations of the Sun and, historically, of celestial radio sources. See also Solar corona.

The total phase of an eclipse is completely safe to watch with the naked eye. The total brightness of the corona is only that of the full moon, so is equally safe to watch. For direct observation of the partial phases, a special solar filter must be used. Fogged and exposed black-and-white (not color) film that contains silver and is developed to full density provides suitable diminution of the solar intensity across the entire spectrum. Inexpensive commercial solar filters made of aluminized Mylar can also be used. Gelatin “neutral-density” filters are actually not neutral in the infrared, and so should not be used. Neutral-density filters made by depositing chromium or other metals on glass are safe if they are ND4 or ND5, and are commercially available, as is #14 welder's glass.

Lunar eclipses

A lunar eclipse can occur only when the Moon is full and is near one of the nodes of its orbit. If the Moon enters only the penumbral cone of the Earth (Fig. 1), the eclipse is a penumbral one. If the Moon enters the umbra without being entirely immersed in it, a partial (umbral) eclipse occurs. The eclipse is total if the entire Moon enters the umbra.

The magnitude of an eclipse is the fraction of the diameter of the lunar disk which is eclipsed (in the umbra or in the penumbra) at maximum phase. If the magnitude is larger than 1, the eclipse is total. Penumbral eclipses are not observable unless their magnitude (in the penumbra) is greater than about 0.7.

If penumbral eclipses as well as umbral ones are taken into consideration, the least number of lunar eclipses during a calendar year is two, and the maximum number is five. If only umbral eclipses are considered, the least number of lunar eclipses in one calendar year is zero, and the maximum number is three.

When the Moon passes through the center of the Earth's shadow, the entire eclipse takes to , depending on the Moon's position in its orbit at the time of the eclipse. The first hour is spent in the penumbra (Fig. 1). No darkening is noticeable until about a quarter hour before the first contact with the umbra, because in the penumbra all of the Moon's side facing Earth is still receiving some direct sunlight. Then as the Moon enters the umbra, the eclipsed part of the Moon appears nearly black by contrast with the bright side of the disk. Approximately the second hour is required for all of the Moon to get into the umbra.

The diameter of the umbra where the Moon crosses it is about times the Moon's diameter. The total phase of a lunar eclipse can last up to 107 min.

If the Earth had no atmosphere, the Moon would disappear from view while in the umbra. However, the Earth's atmosphere acts like a lens and bends the sunlight into the umbra. The longer waves of red light penetrate the atmosphere better than the short-wave blue light, which is scattered to form the blue of the sky. An observer on the Moon would see the Earth surrounded by a thin ring of bright sunset colors. This explains the usual reddish color of the totally eclipsed Moon. Extremely dark eclipses are due to major volcanic eruptions, whose dust temporarily increases the atmosphere's opacity. See also Refraction of waves.

(1) An open source Java-based platform for integrating software tools for application development. Running under Windows and Linux, it provides a universal platform for tools created as Eclipse plug-ins. IBM started the Eclipse consortium in late 2001 with $40 million and donated a large amount of code. In 2004, it was spun off as an independent foundation. For more information, visit www.eclipse.org. See NetBeans.

(2) (ECLIPSE) An early series of 32-bit minicomputers from Data General. The development of the initial 32-bit ECLIPSE MV/8000 was the subject of Tracy Kidder's best-selling book, "Soul of a New Machine" published in 1981 by Little, Brown and Company.

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verb

To make dim or indistinct: becloud, bedim, befog, blear, blur, cloud, dim, dull, fog, gloom, mist, obfuscate, obscure, overcast, overshadow, shadow. See clear/unclear.

Definition: shadowing
Antonyms: rise

v

Definition: obscure, veil
Antonyms: clear, explain, lay out

v

Definition: surpass achievement
Antonyms: fail, fall behind

Lunar Eclipse

From our Archives: Today's Highlights, February 20, 2008

Tutor's tip: Her report explaining the "ellipse" (a mathematical curve) managed to "eclipse" (overpower) the work of the others, although it contained an "ellipsis" (an omission of words; plural: "ellipses").

LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!

The sun is often taken to represent the conscious, rational self and the moon, the subconscious, emotional self. Their union in an eclipse may signify a coming together of separate parts of oneself (self-integration). It may also stand for the "eclipsing" of reason or consciousness by emotion or the subconscious (in a solar eclipse), or vice versa (in a lunar eclipse). We sometimes speak of being "eclipsed," and this may also be the meaning of a dream about eclipses.

In astronomy, the blocking out of light from one object by the intervention of another object. The most dramatic eclipses visible from the Earth are eclipses of the sun (when sunlight is blocked by the moon) and eclipses of the moon (when sunlight on its way to the moon is blocked by the Earth).

• Dead or Dying - eclipsed: (adj) having died

This article is about astronomical eclipses. For other uses, see Eclipse (disambiguation).

"Total eclipse" redirects here. For other uses, see Total Eclipse (disambiguation).

Totality during the 1999 solar eclipse. Solar prominences can be seen along the limb (in red) as well as extensive coronal filaments.

An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. An eclipse is a type of syzygy.^[1]

The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the Moon moves into the Earth's shadow. However, it can also refer to such events beyond the Earth-Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon. A binary star system can also produce eclipses if the plane of the orbit of its constituent stars intersects the observer's position.

Contents 1 Etymology 2 Umbra, penumbra and antumbra 3 Eclipse cycles 4 Earth-Moon System 4.1 Solar eclipse 4.2 Lunar eclipse 4.3 Historical record 5 Other planets 5.1 Gas giants 5.2 Mars 5.3 Pluto 5.4 Mercury and Venus 6 Eclipsing binaries 7 See also 8 References 9 External links 9.1 Image galleries

Etymology

The term is derived from the ancient Greek noun ἔκλειψις (ékleipsis), which means "the abandonment", "the downfall", or "the darkening of a heavenly body", which is derived from the verb ἐκλείπω (ekleípō) which means "to abandon", "to darken", or "to cease to exist,"^[2] a combination of prefix ἐκ- (ek-), from preposition ἐκ (ek), "out," and of verb λείπω (leípō), "to be absent".^[3][4]

Umbra, penumbra and antumbra

Umbra, penumbra and antumbra cast by an opaque object occulting a larger light source.

The region of the Moon's shadow in a solar eclipse is divided into three parts^[5]:

• The umbra, within which the Moon completely covers the Sun (more precisely, its photosphere)
• The antumbra, extending beyond the tip of the umbra, within which the Moon is completely in front of the Sun but too small to completely cover it
• The penumbra, within which the Moon is only partially in front of the Sun

During a lunar eclipse only the umbra and penumbra are applicable. This is because Earth's apparent diameter from the viewpoint of the Moon is nearly 4 times that of the Sun.

The first contact occurs when the Moon's disc first starts to impinge on the Sun's; second contact is when the Moon's disc moves completely within the Sun's; third contact when it starts to move out of the Sun's; and fourth or last contact when it finally leaves the Sun's disc entirely.

(The same terms may be used analogously in describing other eclipses, e.g., the antumbra of Deimos crossing Mars, or Phobos entering Mars's penumbra)

A total eclipse occurs when the observer is within the umbra, an annular eclipse when the observer is within the antumbra, and a partial eclipse when the observer is within the penumbra.

For spherical bodies, when the occulting object is smaller than the star, the length (L) of the umbra's cone-shaped shadow is given by:

where R_s is the radius of the star, R_o is the occulting object's radius, and r is the distance from the star to the occulting object. For Earth, on average L is equal to 1.384×10⁶ km, which is much larger than the Moon's semimajor axis of 3.844×10⁵ km. Hence the umbral cone of the Earth can completely envelop the Moon during a lunar eclipse.^[6] If the occulting object has an atmosphere, however, some of the luminosity of the star can be refracted into the volume of the umbra. This occurs, for example, during an eclipse of the Moon by the Earth—producing a faint, ruddy illumination of the Moon even at totality.

Eclipse cycles

An eclipse cycle takes place when a series of eclipses are separated by a certain interval of time. This happens when the orbital motions of the bodies form repeating harmonic patterns. A particular instance is the saros, which results in a repetition of a solar or lunar eclipse every 6,585.3 days, or a little over 18 years (because this is not a whole number of days, successive eclipses will be visible from different parts of the world).^[7]

Earth-Moon System

A symbolic orbital diagram from the view of the Earth at the center, with the sun and moon projected upon the celestial sphere, showing the Moon's two nodes where eclipses can occur.

An eclipse involving the Sun, Earth and Moon can occur only when they are nearly in a straight line, allowing one to be hidden behind another, viewed from the third. Because the orbital plane of the Moon is tilted with respect to the orbital plane of the Earth (the ecliptic), eclipses can occur only when the Moon is close to the intersection of these two planes (the nodes). The Sun, Earth and nodes are aligned twice a year (during an eclipse season), and eclipses can occur during a period of about two months around these times. There can be from four to seven eclipses in a calendar year, which repeat according to various eclipse cycles, such as a saros.

Between 1901 and 2100 there are the maximum of 7 eclipses in:^[8]

• 4 (penumbral) lunar and 3 solar eclipses: 1908, 2038.
• 4 solar and 3 lunar eclipses: 1917, 1973, 2094.
• 5 solar and 2 lunar eclipses: 1934

Excluding penumbral lunar eclipses, there are a maximum of 7 eclipses in:^[9]

• 1591, 1656, 1787, 1805, 1917, 1935, 1982, and 2094

Solar eclipse

Main article: Solar eclipse

The progression of a solar eclipse on August 1, 2008, viewed from Novosibirsk, Russia. The time between shots is 3 minutes.

A solar eclipse occurs when the Moon passes in front of the Sun as seen from the Earth. The type of solar eclipse event depends on the distance of the Moon from the Earth during the event. A total solar eclipse occurs when the Earth intersects the umbra portion of the Moon's shadow. When the umbra does not reach the surface of the Earth, the Sun is only partially occulted, resulting in an annular eclipse. Partial solar eclipses occur when the viewer is inside the penumbra.^[10]

The eclipse magnitude is the fraction of the Sun's diameter that is covered by the Moon. For a total eclipse, this value is always greater than or equal to one. In both annular and total eclipses, the eclipse magnitude is the ratio of the angular sizes of the Moon to the Sun.^[11]

Solar eclipses are relatively brief events that can only be viewed in totality along a relatively narrow track. Under the most favorable circumstances, a total solar eclipse can last for 7 minutes, 31 seconds, and can be viewed along a track that is up to 250 km wide. However, the region where a partial eclipse can be observed is much larger. The Moon's umbra will advance eastward at a rate of 1,700 km/h, until it no longer intersects the Earth's surface.

During a solar eclipse, the Moon can sometimes perfectly cover the Sun because its size is nearly the same as the Sun's when viewed from the Earth. A total solar eclipse is in fact an occultation while an annular solar eclipse is a transit.

Lunar eclipse

Main article: Lunar eclipse

The progression of a lunar eclipse. Totality is shown with the last two images to lower right. These required a longer exposure time to make the details visible.

Lunar eclipses occur when the Moon passes through the Earth's shadow. Since this occurs only when the Moon is on the far side of the Earth from the Sun, lunar eclipses only occur when there is a full moon. Unlike a solar eclipse, an eclipse of the Moon can be observed from nearly an entire hemisphere. For this reason it is much more common to observe a lunar eclipse from a given location. A lunar eclipse also lasts longer, taking several hours to complete, with totality itself usually averaging anywhere from about 30 minutes to over an hour.^[12]

There are three types of lunar eclipses: penumbral, when the Moon crosses only the Earth's penumbra; partial, when the Moon crosses partially into the Earth's umbra; and total, when the Moon crosses entirely into the Earth's umbra. Total lunar eclipses pass through all three phases. Even during a total lunar eclipse, however, the Moon is not completely dark. Sunlight refracted through the Earth's atmosphere enters the umbra and provides a faint illumination. Much as in a sunset, the atmosphere tends to more strongly scatter light with shorter wavelengths, so the illumination of the Moon by refracted light has a red hue,^[13] thus the phrase 'Blood Moon' is often found in descriptions of such lunar events as far back as eclipses are recorded.^[14]

Historical record

Records of solar eclipses have been kept since ancient times. Eclipse dates can be used for chronological dating of historical records. A Syrian clay tablet records a solar eclipse which occurred on March 5, 1223 B.C.,^[15] while Paul Griffin argues that a stone in Ireland records an eclipse on November 30, 3340 B.C.^[16] Positing classical-era astronomers' use of Babylonian eclipse records mostly from the 13th century BC provides a feasible and mathematically consistent^[17] explanation for the Greek finding all 3 lunar mean motions (synodic, anomalistic, draconitic) to a precision of about 1 part in a million or better. Chinese historical records of solar eclipses date back over 4,000 years and have been used to measure changes in the Earth's rate of spin.^[18]

Other planets

Gas giants

See also: Solar eclipses on Jupiter, Solar eclipses on Saturn, and Solar eclipses on Uranus and Neptune

A picture of Jupiter and its moon Io taken by Hubble. The black spot is Io's shadow.

Saturn occults the Sun as seen from the Cassini–Huygens space probe

The gas giant planets (Jupiter,^[19] Saturn,^[20] Uranus,^[21] and Neptune)^[22] have many moons and thus frequently display eclipses. The most striking involve Jupiter, which has four large moons and a low axial tilt, making eclipses more frequent as these bodies pass through the shadow of the larger planet. Transits occur with equal frequency. It is common to see the larger moons casting circular shadows upon Jupiter's cloudtops.

The eclipses of the Galilean moons by Jupiter became accurately predictable once their orbital elements were known. During the 1670s, it was discovered that these events were occurring about 17 minutes later than expected when Jupiter was on the far side of the Sun. Ole Rømer deduced that the delay was caused by the time needed for light to travel from Jupiter to the Earth. This was used to produce the first estimate of the speed of light.^[23]

On the other three gas giants, eclipses only occur at certain periods during the planet's orbit, due to their higher inclination between the orbits of the moon and the orbital plane of the planet. The moon Titan, for example, has an orbital plane tilted about 1.6° to Saturn's equatorial plane. But Saturn has an axial tilt of nearly 27°. The orbital plane of Titan only crosses the line of sight to the Sun at two points along Saturn's orbit. As the orbital period of Saturn is 29.7 years, an eclipse is only possible about every 15 years. One lunar eclipse sighting of Titan was on September 1 597 BC at 15:50:13 UCT.

The timing of the Jovian satellite eclipses was also used to calculate an observer's longitude upon the Earth. By knowing the expected time when an eclipse would be observed at a standard longitude (such as Greenwich), the time difference could be computed by accurately observing the local time of the eclipse. The time difference gives the longitude of the observer because every hour of difference corresponded to 15° around the Earth's equator. This technique was used, for example, by Giovanni D. Cassini in 1679 to re-map France.^[24]

Mars

Main article: Transit of Phobos from Mars

Transit of Phobos from Mars, as seen by Mars Rover Opportunity

On Mars, only partial solar eclipses (transits) are possible, because neither of its moons is large enough, at their respective orbital radii, to cover the Sun's disc as seen from the surface of the planet. Eclipses of the moons by Mars are not only possible, but commonplace, with hundreds occurring each Earth year. There are also rare occasions when Deimos is eclipsed by Phobos.^[25] Martian eclipses have been photographed from both the surface of Mars and from orbit.

Pluto

Main article: Solar eclipses on Pluto

Pluto, with its proportionately large moon Charon, is also the site of many eclipses. A series of such mutual eclipses occurred between 1985 and 1990.^[26] These daily events led to the first accurate measurements of the physical parameters of both objects.^[27]

Mercury and Venus

Eclipse are impossible on Mercury and Venus, which have no moons. However, both have been observed to transit across the face of the Sun. There are on average 13 transits of Mercury each century. Transits of Venus occur in pairs separated by an interval of eight years, but each pair of events happen less than once a century.^[28]

Eclipsing binaries

A binary star system consists of two stars that orbit around their common center of mass. The movements of both stars lie on a common orbital plane in space. When this plane is very closely aligned with the location of an observer, the stars can be seen to pass in front of each other. The result is a type of extrinsic variable star system called an eclipsing binary.

The maximum luminosity of an eclipsing binary system is equal to the sum of the luminosity contributions from the individual stars. When one star passes in front of the other, the luminosity of the system is seen to decrease. The luminosity returns to normal once the two stars are no longer in alignment.^[29]

The first eclipsing binary star system to be discovered was Algol, a star system in the constellation Perseus. Normally this star system has a visual magnitude of 2.1. However, every 2.867 days the magnitude decreases to 3.4 for more than 9 hours. This is caused by the passage of the dimmer member of the pair in front of the brighter star.^[30] The concept that an eclipsing body caused these luminosity variations was introduced by John Goodricke in 1783.^[31]

See also

• Mursili's eclipse
• Solar eclipse
• List of solar eclipses in the 21st century

References

1. ^ Staff (March 31, 1981). "Science Watch: A Really Big Syzygy" (Press release). The New York Times. http://query.nytimes.com/gst/fullpage.html?sec=health&res=9F02E5DB1039F932A05750C0A967948260&fta=y. Retrieved 2008-02-29. 
2. ^ http://www.in.gr/dictionary/lookup.asp?Word=%E5%EA%EB%E5%DF%F0%F9+++&x=0&y=0
3. ^ http://www.lingvozone.com/main.jsp?action=translation&do=dictionary&language_id_from=23&language_id_to=8&word=%CE%BB%CE%B5%CE%AF%CF%80%CF%89+&t.x=55&t.y=16
4. ^ http://translate.google.com/translate_t?prev=hp&hl=en&js=y&text=%CE%BB%CE%B5%CE%AF%CF%80%CF%89&sl=el&tl=en&history_state0=&swap=1#
5. ^ Espenak, Fred (September 21, 2007). "Glossary of Solar Eclipse Terms". NASA. http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/SEglossary.html. Retrieved 2008-02-28. 
6. ^ Green, Robin M. (1985). Spherical Astronomy. Oxford University Press. ISBN 0-521-31779-7. 
7. ^ Espenak, Fred (July 12, 2007). "Eclipses and the Saros". NASA. http://sunearth.gsfc.nasa.gov/eclipse/SEsaros/SEsaros.html. Retrieved 2007-12-13. 
8. ^ http://hermit.org/Eclipse/when_stats.html
9. ^ http://www.staff.science.uu.nl/~gent0113/eclipse/eclipsecycles.htm
10. ^ Hipschman, R.. "Solar Eclipse: Why Eclipses Happen". http://www.exploratorium.edu/eclipse/why.html. Retrieved 2008-12-01. 
11. ^ Zombeck, Martin V. (2006). Handbook of Space Astronomy and Astrophysics (Third ed.). Cambridge University Press. pp. 48. ISBN 0-521-78242-2. 
12. ^ Staff (January 6, 2006). "Solar and Lunar Eclipses". NOAA. http://www.crh.noaa.gov/fsd/astro/suneclipse.php. Retrieved 2007-05-02. 
13. ^ Phillips, Tony (February 13, 2008). "Total Lunar Eclipse". NASA. http://science.nasa.gov/headlines/y2008/13feb_lunareclipse.htm. Retrieved 2008-03-03. 
14. ^ Ancient Timekeepers, http://blog.world-mysteries.com/science/ancient-timekeepers-part-1-movements-of-the-earth/
15. ^ de Jong, T.; van Soldt, W. H. (1989). "The earliest known solar eclipse record redated". Nature 338 (6212): 238–240. Bibcode 1989Natur.338..238D. doi:10.1038/338238a0. http://www.nature.com/nature/journal/v338/n6212/abs/338238a0.html. Retrieved 2007-05-02. 
16. ^ Griffin, Paul (2002). "Confirmation of World's Oldest Solar Eclipse Recorded in Stone". The Digital Universe. http://www.astronomy.ca/3340eclipse/. Retrieved 2007-05-02. 
17. ^ See DIO 16 p.2 (2009). Though those Greek and perhaps Babylonian astronomers who determined the 3 previously unsolved lunar motions were spread over more than 4 centuries (263 BC to 160 AD), the math-indicated early eclipse records are all from a much smaller span: the 13th century BC. The anciently attested Greek technique: use of eclipse cycles, automatically providing integral ratios, which is how all ancient astronomers' lunar motions were expressed. Long-eclipse-cycle-based reconstructions precisely produce all of the 24 digits appearing in the three attested ancient motions just cited: 6247 synod = 6695 anom (System A), 5458 synod = 5923 drac (Hipparchos), 3277 synod = 3512 anom (Planetary Hypotheses). By contrast, the System B motion, 251 synod = 269 anom (Aristarchos?), could have been determined without recourse to remote eclipse data, simply by using a few eclipse-pairs 4267 months apart.
18. ^ "Solar Eclipses in History and Mythology". Bibliotheca Alexandrina. http://www.bibalex.org/eclipse2006/HistoricalObservationsofSolarEclipses.htm. Retrieved 2007-05-02. 
19. ^ "Start eclipse of the Sun by Callisto from the center of Jupiter". JPL Solar System Simulator. 2009-Jun-03\ 00:28 UT. http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=504&vbody=599&month=6&day=3&year=2009&hour=00&minute=20&fovmul=1&rfov=0.5&bfov=30&brite=1. Retrieved 2008-06-05. 
20. ^ "Eclipse of the Sun by Titan from the center of Saturn". JPL Solar System Simulator. 2009-Aug-03 02:46 UT. http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=606&vbody=699&month=8&day=3&year=2009&hour=02&minute=46&fovmul=1&rfov=5&bfov=30&porbs=1&brite=1. Retrieved 2008-06-05. 
21. ^ "Brief Eclipse of the Sun by Miranda from the center of Uranus". JPL Solar System Simulator. 2007-Jan-22 19:58 UT (JPL Horizons S-O-T=0.0565). http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=705&vbody=799&month=1&day=22&year=2007&hour=19&minute=59&fovmul=1&rfov=2&bfov=30&porbs=1&brite=1. Retrieved 2008-06-05. 
22. ^ "Transit of the Sun by Nereid from the center of Neptune". JPL Solar System Simulator. 2006-Mar-28 20:19 UT (JPL Horizons S-O-T=0.0079). http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=802&vbody=899&month=3&day=28&year=2006&hour=20&minute=40&fovmul=1&rfov=0.05&bfov=30&porbs=1&brite=1. Retrieved 2008-06-05. 
23. ^ "Roemer's Hypothesis". MathPages. http://www.mathpages.com/home/kmath203/kmath203.htm. Retrieved 2007-01-12. 
24. ^ Cassini, Giovanni D. (1694). "Monsieur Cassini His New and Exact Tables for the Eclipses of the First Satellite of Jupiter, Reduced to the Julian Stile, and Meridian of London". Philosophical Transactions 18 (207-214): 237–256. doi:10.1098/rstl.1694.0048. JSTOR 102468. 
25. ^ Davidson, Norman (1985). Astronomy and the Imagination: A New Approach to Man's Experience of the Stars. Routledge. ISBN 0-7102-0371-3. 
26. ^ Buie, M. W.; Polk, K. S. (1988). "Polarization of the Pluto-Charon System During a Satellite Eclipse". Bulletin of the American Astronomical Society 20: 806. Bibcode 1988BAAS...20..806B. 
27. ^ Tholen, D. J.; Buie, M. W.; Binzel, R. P.; Frueh, M. L. (1987). "Improved Orbital and Physical Parameters for the Pluto-Charon System". Science 237 (4814): 512–514. Bibcode 1987Sci...237..512T. doi:10.1126/science.237.4814.512. PMID 17730324. http://www.sciencemag.org/cgi/content/refs/237/4814/512. Retrieved 2008-03-11. 
28. ^ Espenak, Fred (May 29, 2007). "Planetary Transits Across the Sun". NASA. http://sunearth.gsfc.nasa.gov/eclipse/transit/transit.html. Retrieved 2008-03-11. 
29. ^ Bruton, Dan. "Eclipsing binary stars". Midnightkite Solutions. http://www.physics.sfasu.edu/astro/ebstar/ebstar.html. Retrieved 2007-05-01. 
30. ^ Price, Aaron (January 1999). "Variable Star Of The Month: Beta Persei (Algol)". AAVSO. Archived from the original on 2007-04-05. http://web.archive.org/web/20070405003853/http://www.aavso.org/vstar/vsots/0199.shtml. Retrieved 2007-05-01. 
31. ^ Goodricke, John; Englefield, H. C. (1785). "Observations of a New Variable Star". Philosophical Transactions of the Royal Society of London 75 (0): 153–164. Bibcode 1785RSPT...75..153G. doi:10.1098/rstl.1785.0009. 

External links

Wikimedia Commons has media related to: Eclipse

• A Catalogue of Eclipse Cycles
• Search 5,000 years of eclipses
• NASA eclipse home page
• International Astronomical Union's Working Group on Solar Eclipses
• Mark's eclipse chasing website
• Interactive eclipse maps site

Image galleries

• The World at Night Eclipse Gallery
• Solar and Lunar Eclipse Image Gallery
• Williams College eclipse collection of images
• Prof. Druckmüller's eclipse photography site
• Eclipses: 20 Amazing Photos — slideshow by Life magazine

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Common misspelling(s) of eclipse

• eclispe

Dansk (Danish)
n. - formørkelse, fordunkling, fald
v. tr. - formørke, fordunkle

idioms:

• eclipse of the moon    måneformørkelse
• eclipse of the sun    solformørkelse
• lunar eclipse    måneformørkelse
• solar eclipse    solformørkelse

Nederlands (Dutch)
verduisteren, overschaduwen, verduistering, ondergang

Français (French)
n. - (Astron, fig) éclipse
v. tr. - (Astron) éclipser, (fig) éclipser, faire pâlir, surpasser

idioms:

• eclipse of the moon    éclipse de la Lune
• eclipse of the sun    éclipse du Soleil
• lunar eclipse    éclipse lunaire
• solar eclipse    éclipse solaire

Deutsch (German)
v. - verfinstern, in den Schatten stellen
n. - Finsternis, Eklipse, Niedergang

idioms:

• eclipse of the moon    Mondfinsternis
• eclipse of the sun    Sonnenfinsternis
• lunar eclipse    Mondfinsternis
• solar eclipse    Sonnenfinsternis

Ελληνική (Greek)
v. - (αστρον.) επιφέρω έκλειψη, (μτφ.) επισκιάζω
n. - (αστρον.) έκλειψη, (μτφ.) επισκίαση, αμαύρωση, ξεθώριασμα

idioms:

• eclipse of the moon    έκλειψη της σελήνης
• eclipse of the sun    έκλειψη ηλίου
• lunar eclipse    έκλειψη της σελήνης
• solar eclipse    έκλειψη ηλίου

Italiano (Italian)
eclissare, eclissi

idioms:

• eclipse of the moon    eclissi lunare
• eclipse of the sun    eclissi solare
• lunar eclipse    eclissi lunare
• solar eclipse    eclissi solare

Português (Portuguese)
v. - ocultar
n. - eclipse (m)

idioms:

• eclipse of the moon    eclipse (m) da lua (Astron.)
• eclipse of the sun    eclipse (m) do sol (Astron.)
• lunar eclipse    eclipse (m) lunar (Astron.)
• solar eclipse    eclipse (m) solar (Astron.)

Русский (Russian)
затмевать, заслонять, омрачать, затмение

idioms:

• eclipse of the moon    лунное затмение
• eclipse of the sun    солнечное затмение
• lunar eclipse    лунное затмение
• solar eclipse    солнечное затмение

Español (Spanish)
n. - eclipse
v. tr. - eclipsar, oscurecer

idioms:

• eclipse of the moon    eclipse de luna
• eclipse of the sun    eclipse de sol
• lunar eclipse    eclipse lunar
• solar eclipse    eclipse solar

Svenska (Swedish)
v. - bli förmörkelse
n. - eklips, förmörkelse

中文（简体）(Chinese (Simplified))
日蚀, 衰落, 月蚀, 蚀, 遮蔽, 投下阴影, 使失色

idioms:

• eclipse of the moon    月蚀
• eclipse of the sun    日蚀
• lunar eclipse    月蚀
• solar eclipse    日蚀

中文（繁體）(Chinese (Traditional))
n. - 日蝕, 衰落, 月蝕
v. tr. - 蝕, 遮蔽, 投下陰影, 使失色

idioms:

• eclipse of the moon    月蝕
• eclipse of the sun    日蝕
• lunar eclipse    月蝕
• solar eclipse    日蝕

한국어 (Korean)
n. - 해와 달의 식, 빛의 소멸
v. tr. - 덮어 가리다, 무색케 하다

日本語 (Japanese)
n. - 食, 失墜
v. - 食する, …より断然勝る, 影を落とす, しのぐ

idioms:

• eclipse of the moon    月食
• eclipse of the sun    日食

العربيه (Arabic)
‏(فعل) يكسف, يتفوق على (الاسم) كسوف, خسوف‏

עברית (Hebrew)
n. - ‮ליקוי חמה או ליקוי לבנה, ליקוי מאורות, שקיעה מהירה של חשיבות או התבלטות‬
v. tr. - ‮האפיל על, גרם לליקוי מאורות, הטיל צל על‬

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