Eclipse

Last updated

Totality during the 1999 solar eclipse. Solar prominences can be seen along the limb (in red) as well as extensive coronal filaments. Solar eclipse 1999 4.jpg
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 or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three celestial objects is known as a syzygy. [1] Apart from syzygy, the term eclipse is also used when a spacecraft reaches a position where it can observe two celestial bodies so aligned. An eclipse is the result of either an occultation (completely hidden) or a transit (partially hidden).

Contents

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.

For the special cases of solar and lunar eclipses, these only happen during an "eclipse season", the two times of each year when the plane of the Earth's orbit around the Sun crosses with the plane of the Moon's orbit around the Earth when that line of intersecting planes points near the Sun. The type of solar eclipse that happens during each season (whether total, annular, hybrid, or partial) depends on apparent sizes of the Sun and Moon. If the orbit of the Earth around the Sun, and the Moon's orbit around the Earth were both in the same plane with each other, then eclipses would happen each and every month. There would be a lunar eclipse at every full moon, and a solar eclipse at every new moon. And if both orbits were perfectly circular, then each solar eclipse would be the same type every month. It is because of the non-planar and non-circular differences that eclipses are not a common event. Lunar eclipses can be viewed from the entire nightside half of the Earth. But solar eclipses, particularly total eclipses occurring at any one particular point on the Earth's surface, are very rare events that can be many decades apart.

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 Umbra01.svg
Umbra, penumbra and antumbra cast by an opaque object occulting a larger light source

For any two objects in space, a line can be extended from the first through the second. The latter object will block some amount of light being emitted by the former, creating a region of shadow around the axis of the line. Typically these objects are moving with respect to each other and their surroundings, so the resulting shadow will sweep through a region of space, only passing through any particular location in the region for a fixed interval of time. As viewed from such a location, this shadowing event is known as an eclipse. [5]

Typically the cross-section of the objects involved in an astronomical eclipse are roughly disk shaped. [5] The region of an object's shadow during an eclipse is divided into three parts: [6]

Sun-Moon configurations that produce a total (A), annular (B), and partial (C) solar eclipse Solar eclipse types.svg
Sun-Moon configurations that produce a total (A), annular (B), and partial (C) solar eclipse

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. During a lunar eclipse only the umbra and penumbra are applicable, because the antumbra of the Sun-Earth system lies far beyond the Moon. Analogously, Earth's apparent diameter from the viewpoint of the Moon is nearly four times that of the Sun and thus cannot produce an annular eclipse. 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.

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

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 Rs is the radius of the star, Ro 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. [7] 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 Earthproducing a faint, ruddy illumination of the Moon even at totality.

On Earth, the shadow cast during an eclipse moves very approximately at 1 km per sec. This depends on the location of the shadow on the Earth and the angle in which it is moving. [8]

Eclipse cycles

An eclipse cycle takes place when eclipses in a series 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. [9] In one saros period there are 239.0 anomalistic periods, 241.0 sidereal periods, 242.0 nodical periods, and 223.0 synodic periods. Although the orbit of the Moon does not give exact integers, the numbers of orbit cycles are close enough to integers to give strong similarity for eclipses spaced at 18.03 yr intervals.

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. Lunar eclipse diagram-en.svg
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 seven eclipses in: [10]

Excluding penumbral lunar eclipses, there are a maximum of seven eclipses in: [11]

Solar eclipse

The progression of a solar eclipse on August 1, 2008, viewed from Novosibirsk, Russia. The time between shots is three minutes. 2008-08-01 Solar eclipse progression with timestamps.jpg
The progression of a solar eclipse on August 1, 2008, viewed from Novosibirsk, Russia. The time between shots is three minutes.

As observed from the Earth, a solar eclipse occurs when the Moon passes in front of the Sun. 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. [12]

Each icon shows the view from the centre of its black spot, representing the Moon (not to scale) Solar eclipse visualisation.svg
Each icon shows the view from the centre of its black spot, representing the Moon (not to scale)

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. [13]

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.

Geometry of a total solar eclipse (not to scale) Geometry of a Total Solar Eclipse.svg
Geometry of a total solar eclipse (not to scale)

During a solar eclipse, the Moon can sometimes perfectly cover the Sun because its apparent 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.

When observed at points in space other than from the Earth's surface, the Sun can be eclipsed by bodies other than the Moon. Two examples include when the crew of Apollo 12 observed the Earth to eclipse the Sun in 1969 and when the Cassini probe observed Saturn to eclipse the Sun in 2006.

The progression of a lunar eclipse from right to left. Totality is shown with the first two images. These required a longer exposure time to make the details visible. Eclipse lune.jpg
The progression of a lunar eclipse from right to left. Totality is shown with the first two images. These required a longer exposure time to make the details visible.

Lunar eclipse

Lunar eclipses occur when the Moon passes through the Earth's shadow. This happens only during a full moon, when the Moon is on the far side of the Earth from the Sun. 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 lasts longer, taking several hours to complete, with totality itself usually averaging anywhere from about 30 minutes to over an hour. [14]

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, [15] thus the phrase 'Blood Moon' is often found in descriptions of such lunar events as far back as eclipses are recorded. [16]

Historical record

This print shows Parisians watching the solar eclipse of July 28, 1851 Les parisiens pendant l'eclipse du 28 Juillet.jpg
This print shows Parisians watching the solar eclipse of July 28, 1851
Indian Mathematician Aryabhata's book Aryabhatia (5th century AD), which has an explanantion to the occurrence of solar and lunar eclipses. Aryabhatiya of Aryabhata, English translation.djvu
Indian Mathematician Aryabhata's book Aryabhatia (5th century AD), which has an explanantion to the occurrence of solar and lunar eclipses.

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, in the Ugaritic language, records a solar eclipse which occurred on March 5, 1223 B.C., [17] while Paul Griffin argues that a stone in Ireland records an eclipse on November 30, 3340 B.C. [18] Positing classical-era astronomers' use of Babylonian eclipse records mostly from the 13th century BC provides a feasible and mathematically consistent [19] explanation for the Greek finding all three lunar mean motions (synodic, anomalistic, draconitic) to a precision of about one part in a million or better. Chinese historical records of solar eclipses date back over 3,000 years and have been used to measure changes in the Earth's rate of spin. [20]

In 5th century AD, solar and lunar eclipses were scientifically explained by Aryabhata, in his book Aryabhatia. [21] Aryabhata states that the Moon and planets shine by reflected sunlight and explains eclipses in terms of shadows cast by and falling on Earth. Aryabhata provides the computation and the size of the eclipsed part during an eclipse. Aryabhata's computations were so accurate that 18th-century scientist Guillaume Le Gentil, during a visit to Pondicherry, India, found the Indian computations of the duration of the lunar eclipse of 30 August 1765 to be short by 41 seconds, whereas Le Gentil's charts were long by 68 seconds.[ citation needed ]

By the 1600s, European astronomers were publishing books with diagrams explaining how lunar and solar eclipses occurred. [22] [23] In order to disseminate this information to a broader audience and decrease fear of the consequences of eclipses, booksellers printed broadsides explaining the event either using the science or via astrology. [24]

Eclipses in Mythology & Religion

Before eclipses were understood as well as they are today, there was a much more fearful connotation surrounding the seemingly inexplicable events. There was very considerable confusion regarding eclipses before the 17th century because eclipses were not very accurately or scientifically described until Johannes Kepler provided a scientific explanation for eclipses in the early seventeenth century. [25] Typically in mythology, eclipses were understood to be one variation or another of a spiritual battle between the sun and evil forces or spirits of darkness. [26] The phenomenon of the sun seeming to disappear was a very fearful sight to all who did not understand the science of eclipses as well as those who supported and believed in the idea of mythological gods. The sun was highly regarded as divine by many old religions, and some even viewed eclipses as the sun god being overwhelmed by evil spirits. [27] More specifically, in Norse mythology, it is believed that there is a wolf by the name of Fenrir that is in constant pursuit of the sun, and eclipses are thought to occur when the wolf successfully devours the divine sun. [28] Other Norse tribes believe that there are two wolves by the names of Sköll and Hati that are in pursuit of the sun and the moon, known by the names of Sol and Mani, and these tribes believe that an eclipse occurs when one of the wolves successfully eats either the sun or the moon. [29] Once again, this mythical explanation was a very common source of fear for the majority of people at the time who believed the sun to be a sort of divine power or god because the known explanations of eclipses were quite frequently viewed as the downfall of their highly regarded god. Similarly, other mythological explanations of eclipses describe the phenomenon of darkness covering the sky during the day as a war between the gods of the sun and the moon.

In most types of mythologies and certain religions, eclipses were seen as a sign that the gods were angry and that danger was soon to come, so people often altered their actions in an effort to dissuade the gods from unleashing their wrath. In the Hindu religion, for example, people often sing religious hymns for protection from the evil spirits of the eclipse, and many people of the Hindu religion refuse to eat during an eclipse to avoid the effects of the evil spirits. [30] All food that had been stored before the eclipse is to be thrown out to avoid contamination by spirits, and Hindu people living in India will also wash off in the Ganges River, which is believed to be spiritually cleansing, directly following an eclipse to clean themselves of the evil spirits. [30] In early Judaism and Christianity, eclipses were viewed as signs from God, and some eclipses were seen as a display of God's greatness or even signs of cycles of life and death. [30] However, more ominous eclipses such as a blood moon were believed to be a divine sign that God would soon destroy their enemies. [30]

Other planets and dwarf planets

Gas giants

A picture of Jupiter and its moon Io taken by Hubble. The black spot is Io's shadow. JupiterandIo.jpg
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 Saturn eclipse.jpg
Saturn occults the Sun as seen from the Cassini–Huygens space probe

The gas giant planets 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. [31]

On the other three gas giants (Saturn, Uranus and Neptune) 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.

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. [32]

Mars

Transit of Phobos from Mars, as seen by the Mars Opportunity rover (10 March 2004). PIA05553.gif
Transit of Phobos from Mars, as seen by the Mars Opportunity rover (10 March 2004).

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. [33] Martian eclipses have been photographed from both the surface of Mars and from orbit.

Pluto

Pluto, with its proportionately largest moon Charon, is also the site of many eclipses. A series of such mutual eclipses occurred between 1985 and 1990. [34] These daily events led to the first accurate measurements of the physical parameters of both objects. [35]

Mercury and Venus

Eclipses are impossible on Mercury and Venus, which have no moons. However, as seen from the Earth, 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. [36] According to NASA, the next pair of Venus transits will occur on December 10, 2117 and December 8, 2125. Transits of Mercury are much more common. [37]

Eclipsing binaries

A binary star system consists of two stars that orbit around their common centre 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. [38]

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 nine hours. This is caused by the passage of the dimmer member of the pair in front of the brighter star. [39] The concept that an eclipsing body caused these luminosity variations was introduced by John Goodricke in 1783. [40]

Types

Sun - Moon - Earth: Solar eclipse | annular eclipse | hybrid eclipse | partial eclipse

Sun - Earth - Moon: Lunar eclipse | penumbral eclipse | partial lunar eclipse | central lunar eclipse

Sun - Phobos - Mars: Transit of Phobos from Mars | Solar eclipses on Mars

Sun - Deimos - Mars: Transit of Deimos from Mars | Solar eclipses on Mars

Other types: Solar eclipses on Jupiter | Solar eclipses on Saturn | Solar eclipses on Uranus | Solar eclipses on Neptune | Solar eclipses on Pluto

See also

Related Research Articles

Lunar eclipse When the Moon moves into the Earths shadow

A lunar eclipse occurs when the Moon moves into the Earth's shadow. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned with Earth between the other two, and only on the night of a full moon. The type and length of a lunar eclipse depend on the Moon's proximity to either node of its orbit.

Timeline of Solar System astronomy Timeline of the history of Solar System astronomy

The following is a timeline of Solar System astronomy.

Eclipse cycle Calculation and prediction of eclipses

Eclipses may occur repeatedly, separated by certain intervals of time: these intervals are called eclipse cycles. The series of eclipses separated by a repeat of one of these intervals is called an eclipse series.

Umbra, penumbra and antumbra Distinct parts of a shadow

The umbra, penumbra and antumbra are three distinct parts of a shadow, created by any light source after impinging on an opaque object. Assuming no diffraction, for a collimated beam of light, only the umbra is cast.

Shadow Area where direct light from a light source cannot reach due to obstruction by an object

A shadow is a dark area where light from a light source is blocked by an opaque object. It occupies all of the three-dimensional volume behind an object with light in front of it. The cross section of a shadow is a two-dimensional silhouette, or a reverse projection of the object blocking the light.

Occultation occlusion of an object by another object that passes between it and the observer

An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks from view (occults) an object in the background. In this general sense, occultation applies to the visual scene observed from low-flying aircraft when foreground objects obscure distant objects dynamically, as the scene changes over time.

Extraterrestrial sky Extraterrestrial view of outer space

In astronomy, an extraterrestrial sky is a view of outer space from the surface of an astronomical body other than Earth.

Transit of Deimos from Mars Transit of a Moon of Mars

A transit of Deimos across the Sun as seen from Mars occurs when Deimos passes directly between the Sun and a point on the surface of Mars, obscuring a small part of the Sun's disc for an observer on Mars. During a transit, Deimos can be seen from Mars as a small dark spot rapidly moving across the Sun's face.

Solar eclipses on Jupiter When moons of Jupiter pass before the Sun

Solar eclipses on Jupiter occur when any of the natural satellites of Jupiter pass in front of the Sun as seen from the planet Jupiter.

Solar eclipse of October 3, 2005 21st-century annular solar eclipse

An annular solar eclipse occurred at the Moon's descending node of the orbit on October 3, 2005, with a magnitude of 0.958. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring only 4.8 days after apogee, the Moon's apparent diameter was smaller. It was visible from a narrow corridor through the Iberian peninsula and Africa. A partial eclipse was seen from the much broader path of the Moon's penumbra, including all of Europe, Africa and southwestern Asia. The Sun was 96% covered in a moderate annular eclipse, lasting 4 minutes and 32 seconds and covering a broad path up to 162 km wide. The next solar eclipse in Africa occurred just 6 months later.

Magnitude of eclipse

The magnitude of eclipse is the fraction of the angular diameter of a celestial body being eclipsed. This applies to all celestial eclipses. The magnitude of a partial or annular solar eclipse is always between 0.0 and 1.0, while the magnitude of a total solar eclipse is always greater than or equal to 1.0.

Solar eclipse Natural phenomenon wherein the Sun is obscured by the Moon

A solar eclipse occurs when a portion of the Earth is engulfed in a shadow cast by the Moon which fully or partially blocks sunlight. This occurs when the Sun, Moon and Earth are aligned. Such alignment coincides with a new moon (syzygy) indicating the Moon is closest to the ecliptic plane. In a total eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses, only part of the Sun is obscured.

February 2008 lunar eclipse Total lunar eclipse of 20 February 2008

A total lunar eclipse occurred on February 20 and February 21, 2008. It was visible in the eastern evening sky on February 20 for all of North and South America, and on February 21 in the predawn western sky from most of Africa and Europe. Greatest Eclipse occurring on Thursday, February 21, 2008 at 03:26:03 UTC, totality lasting 49 minutes and 45.6 seconds.

April 2014 lunar eclipse Total lunar eclipse in April 2014

A total lunar eclipse took place on 15 April 2014. It was the first of two total lunar eclipses in 2014, and the first in a tetrad. Subsequent eclipses in the tetrad are those of 8 October 2014, 4 April 2015, and 28 September 2015. Occurring 6.7 days after apogee, the Moon's apparent diameter was smaller.

October 2014 lunar eclipse Partial lunar eclipse of 8 October 2014

A total lunar eclipse took place on 8 October 2014. It is the second of two total lunar eclipses in 2014, and the second in a tetrad. Other eclipses in the tetrad are those of 15 April 2014, 4 April 2015, and 28 September 2015. Occurring only 2.1 days after perigee, the Moon's apparent diameter was larger, 1960.6 arcseconds.

Gamma (eclipse) Parameter of an eclipse that describes how centrally the shadow of the Moon or Earth strikes the other

Gamma of an eclipse describes how centrally the shadow of the Moon or Earth strikes the other body. This distance, measured at the moment when the axis of the shadow cone passes closest to the center of the Earth or Moon, is stated as a fraction of the equatorial radius of the Earth or Moon.

Solar eclipse of October 2, 2024 Future annular solar eclipse

An annular solar eclipse will occur on Wednesday, October 2, 2024. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide.

Syzygy (astronomy) Configuration of celestial bodies

In astronomy, a syzygy is a roughly straight-line configuration of three or more celestial bodies in a gravitational system.

Solar eclipses on the Moon Lunar phenomenon wherein the Sun is obscured by Earth

Solar eclipses on the Moon are caused when the planet Earth passes in front of the Sun and blocks its light. Viewers on Earth experience a lunar eclipse during a solar eclipse on the Moon.

The word "transit" refers to cases where the nearer object appears smaller than the more distant object. Cases where the nearer object appears larger and completely hides the more distant object are known as occultations.

References

  1. Staff (March 31, 1981). "Science Watch: A Really Big Syzygy". The New York Times (Press release). Archived from the original on December 10, 2008. Retrieved 2008-02-29.
  2. "in.gr". Archived from the original on 2018-05-11. Retrieved 2009-09-24.
  3. "LingvoSoft". lingvozone.com. Archived from the original on 2013-01-28.
  4. "Google Translate". translate.google.com.
  5. 1 2 Westfall, John; Sheehan, William (2014), Celestial Shadows: Eclipses, Transits, and Occultations, Astrophysics and Space Science Library, 410, Springer, pp. 1–5, ISBN   978-1493915354.
  6. Espenak, Fred (September 21, 2007). "Glossary of Solar Eclipse Terms". NASA. Archived from the original on February 24, 2008. Retrieved 2008-02-28.
  7. Green, Robin M. (1985). Spherical Astronomy. Oxford University Press. ISBN   978-0-521-31779-5.
  8. "Speed of eclipse shadow? - Sciforums". sciforums.com. Archived from the original on 2015-04-02.
  9. Espenak, Fred (July 12, 2007). "Eclipses and the Saros". NASA. Archived from the original on 2007-10-30. Retrieved 2007-12-13.
  10. Smith, Ian Cameron. "Eclipse Statistics". moonblink.info. Archived from the original on 2014-05-27.
  11. Gent, R.H. van. "A Catalogue of Eclipse Cycles". webspace.science.uu.nl. Archived from the original on 2011-09-05.
  12. Hipschman, R. (2015-10-29). "Solar Eclipse: Why Eclipses Happen". Archived from the original on 2008-12-05. Retrieved 2008-12-01.
  13. Zombeck, Martin V. (2006). Handbook of Space Astronomy and Astrophysics (Third ed.). Cambridge University Press. p.  48. ISBN   978-0-521-78242-5.
  14. Staff (January 6, 2006). "Solar and Lunar Eclipses". NOAA. Archived from the original on May 12, 2007. Retrieved 2007-05-02.
  15. Phillips, Tony (February 13, 2008). "Total Lunar Eclipse". NASA. Archived from the original on March 1, 2008. Retrieved 2008-03-03.
  16. Ancient Timekeepers, "Archived copy". 2011-09-16. Archived from the original on 2011-10-26. Retrieved 2011-10-25.CS1 maint: archived copy as title (link)
  17. 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. S2CID   186243477.
  18. Griffin, Paul (2002). "Confirmation of World's Oldest Solar Eclipse Recorded in Stone". The Digital Universe. Archived from the original on 2007-04-09. Retrieved 2007-05-02.
  19. See DIO 16 Archived 2011-07-26 at the Wayback Machine p.2 (2009). Though those Greek and perhaps Babylonian astronomers who determined the three previously unsolved lunar motions were spread over more than four centuries (263 BC to 160 AD), the math-indicated early eclipse records are all from a much smaller span Archived 2015-04-02 at the Wayback Machine : 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.
  20. "Solar Eclipses in History and Mythology". Bibliotheca Alexandrina. Archived from the original on 2007-04-08. Retrieved 2007-05-02.
  21. "Aryabhata | Achievements, Biography, & Facts | Britannica". www.britannica.com. Retrieved 2021-12-25.
  22. Girault, Simon (1592). Globe dv monde contenant un bref traite du ciel & de la terra. Langres, France. p. Fol. 8V.
  23. Hevelius, Johannes (1652). Observatio Eclipseos Solaris Gedani. Danzig, Poland.
  24. Stephanson, Bruce; Bolt, Marvin; Friedman, Anna Felicity (2000). The Universe Unveiled: Instruments and Images through History. Cambridge, UK: Cambridge University Press. pp. 32–33. ISBN   978-0521791434.
  25. Angerhausen, Daniel; DeLarme, Em; Morse, Jon A. (2015-11-01). "A Comprehensive Study of Kepler Phase Curves and Secondary Eclipses: Temperatures and Albedos of Confirmed Kepler Giant Planets". Publications of the Astronomical Society of the Pacific. 127 (957): 1113. arXiv: 1404.4348 . doi:10.1086/683797. ISSN   1538-3873. S2CID   118462488.
  26. Littmann, Mark; Espenak, Fred; Willcox, Ken (2008-07-17). Totality: Eclipses of the Sun. OUP Oxford. ISBN   978-0-19-157994-3.
  27. Knutson, Sara Ann (2019-06-29). "The Materiality of Myth: Divine Objects in Norse Mythology". Temenos - Nordic Journal of Comparative Religion. 55 (1): 29–53. doi:10.33356/temenos.83424. ISSN   2342-7256. S2CID   198570032.
  28. Lindow, John (2002-10-17). Norse Mythology: A Guide to Gods, Heroes, Rituals, and Beliefs. Oxford University Press. ISBN   978-0-19-983969-8.
  29. Morrison, Jessica (2017-08-01). Eclipses. Weigl Publishers. ISBN   978-1-4896-5814-2.
  30. 1 2 3 4 Musharraf, Muhammad Nabeel; Dars, Dr Basheer Ahmed (2021-09-15). "Eclipses, Mythology, and Islam". Al-Duhaa. 2 (2): 01–16. doi:10.51665/al-duhaa.002.02.0077. ISSN   2710-0812.
  31. "Roemer's Hypothesis". MathPages. Archived from the original on 2011-02-24. Retrieved 2007-01-12.
  32. 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 of the Royal Society . 18 (207–214): 237–256. Bibcode:1694RSPT...18..237C. doi: 10.1098/rstl.1694.0048 . JSTOR   102468.
  33. Davidson, Norman (1985). Astronomy and the Imagination: A New Approach to Man's Experience of the Stars. Routledge. ISBN   978-0-7102-0371-7.
  34. 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.
  35. 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. S2CID   33536340.
  36. Espenak, Fred (May 29, 2007). "Planetary Transits Across the Sun". NASA. Archived from the original on March 11, 2008. Retrieved 2008-03-11.
  37. "When will the next transits of Mercury and Venus occur during a total solar eclipse? | Total Solar Eclipse 2017". eclipse2017.nasa.gov. Archived from the original on 2017-09-18. Retrieved 2017-09-25.
  38. Bruton, Dan. "Eclipsing binary stars". Midnightkite Solutions. Archived from the original on 2007-04-14. Retrieved 2007-05-01.
  39. Price, Aaron (January 1999). "Variable Star Of The Month: Beta Persei (Algol)". AAVSO. Archived from the original on 2007-04-05. Retrieved 2007-05-01.
  40. Goodricke, John; Englefield, H. C. (1785). "Observations of a New Variable Star". Philosophical Transactions of the Royal Society of London. 75: 153–164. Bibcode:1785RSPT...75..153G. doi: 10.1098/rstl.1785.0009 .
Image galleries