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Eclipse!. A Presentation to Astronomy Ireland By: David Grennan, 27 th February 2006. Solar Eclipses - Past, Present, and Future. Eclipse Mythology Chinese, Hindu, Egyptian , Impact on modern day science and religion. Mechanics of Solar Eclipses Why eclipses occur . Types of Eclipse .
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Eclipse! A Presentation to Astronomy Ireland By: David Grennan, 27th February 2006
Solar Eclipses - Past, Present, and Future. Eclipse Mythology Chinese, Hindu, Egyptian, Impact on modern day science and religion. Mechanics of Solar Eclipses Why eclipses occur. Types of Eclipse. Phases of an eclipse. Shadows Bailys Beads. Diamond Ring. Temperature Corona. Prominences.
Solar Eclipses - Past, Present, and Future. Safely Viewing Eclipses Eclipse, March 29, 2006 aguide. Using computer simulations Eclipse from Ireland. Eclipse from Turkey. Eclipse from Space Future Eclipses Important Eclipses present – 2030 The 'almost' total eclipse of 2015 from Ireland.
Eclipse Lore and Mythology "Nothing there is beyond hope, nothing that can be sworn impossible, nothing wonderful, since Zeus, father of the Olympians, made night from mid-day, hiding the light of the shining Sun, and sore fear came upon men." Archilochus(c.710 - 676 BC)
Eclipse Lore and Mythology Our ancestors saw eclipses as evil omens, often as portents of some catastrophic event or a sign from their deities. The earliest recorded eclipse was in China on October 22, 2134 BC. The two court astrologers to the Emporer lost their heads because,theyhad failed to predict it The Babylonians were the first to calculate the regular intervals at which eclipses occur. Thales of Miletus predicted a solar eclipse that marked the beginning of the Greek scientific/philosophic era.
Eclipse Lore and Mythology Word eclipse comes from a Greek word, “ekleipsis” meaning abandonment. There is a story that suggests Christopher Columbus used his Knowledge of an upcoming lunar eclipse to great effect.
Ancient China People of ancient China were convinced that eclipses Occurred because a great dragon (or toad, or dog) was Devouring the Sun. They made load noises, banged implements etc to scare Away the dragon. As total eclipses can only last a maximum of 7 ½ minutes There raucous behaviour always had the desired effect.
Ancient China Han Dynasty (206 BC - 220 AD)
Hindu Folklore According to Hindu mythology, the eclipse represents the demons Rahu and Keta locked in celestial combat and eating the Sun.
Hindu Folklore The Godswere drinking the elixir of immortality. The demon Rahu slipped into their midst and stole a sip. Surya (the sun) and Soma (the moon) reported the incident to the great deity Vishnu. Vishnu promptly sought out the impudent Rahu and lopped off his head. But having become deathless, Rahu survived and to this day seeks revenge on the tattletales by devouring them.
Ancient Egypt The egyptian word for eclipse is ‘Akhet’ King Akhenaten (1356-1338 BC) built his capital according to the totality path of the solar eclipse of 08/15/-1351. The Pharaoh named his new residence 'Akhet Aten'. The name of the city means: 'The Eclipse of Aten'. The name of the Giza Sphinx was 'Hor in the Akhet‘ Many different ancient egyptian sun cults saw eclipses Differently. Many refer to a serpent eating the Sun God. Most however refer to a great hawk stealing RA’s glory.
Eclipses and Religion Many hindus to this day immerse themselves in holy rivers And lakes during solar eclipses. Working during eclipses is considered bad luck. Muslim tradition holds that the prophet Mohammed, the founder of Islam, prayed for the duration of an eclipse. Senior muslim clerics issued an edict forbidding people to look at the Sun directly because it transgresses Islamic law to harm oneself. Druids believe eclipse represents man and woman together.
Eclipses and Religion Luke 23:44-48 “And it was about the sixth hour, and there was a darkness over all the earth until the ninth hour. And the sun was darkened, and the veil of the temple was rent in the midst.” Some suggest a solar eclipse as an explaination for The ‘darkness’ however the facts don’t lend credance.
Mechanics of Solar Eclipses Solar eclipse of 11 Aug 1999 From MIR Spacestation.
Mechanics of Solar Eclipses Todo insert flash file.
Partial Eclipse
Total Eclipse Although a total eclipse refers to a specific event, the events leading Up to ‘totality’ and following it also hold much interest. • Partial Phase • Shadows • Bailys Beads • Diamond Ring • Totality
Partial Phase During the partial phase there are many interesting things to note. • First Contact. • Eclipse increasing in magnitude. • Temperature. • Increasing Darkness • Shadow Bands • Crescent Shadows • Creatures settling believing night is imminent • Moons shadow racing from the west(ish). • Bailys Beads • Diamond Ring
First Contact. The moment when the western limb of the Moon contacts the Eastern limb of the Sun. First contact is not directly Visible, however very shortly Afterwards a little ‘bite’ is Taken from the Sun.
Temperature As the eclipse increases in magnitude, the amount of warming Sunlight reaching us falls. As the eclipse reaches 70-80% you will begin to feel a noticeable Coolness as if night were coming.
Increasing Darkness With the decrease in the area of Sun presented to us Ambient light levels fall. Most noticeable in the latter stages of the eclipse. Video from west Africa showing this dramatically.
Shadow Bands Caused by distortions in the Earth’s atmosphere and the partially Eclipsed Sun. Best seen on a pale coloured Wall or concrete pavement.
Crescent Shadows Note shadows cast by irregularly shaped objects such as leaves From trees.
Bailys Beads. At this point the only sunlight reaching us is through the undulating Valleys on the Moons limb.
Diamond Ring The chromosphere is visible and the ‘Corona’ is becoming visible. The very last of ‘Bailys Beads’ is also visible. Totality is now imminent!!!!!!
The Hybrid Eclipse. The official explaination! “A hybrid eclipse is a unique type of central eclipse where parts of the path are annular while other parts are total. This duality comes about when the vertex of the Moon's umbral shadow pierces Earth's surface at some points, but falls short of the planet along other portions of the eclipse path. The curvature of Earth's surface brings some geographic locations along the path into the umbra while other positions are more distant and enter the antumbral rather than umbral shadow.” Fred Espenak
The Hybrid Eclipse. In practice!
Safely Viewing Eclipses
Eclipse Safety Directly looking at the Sun, even for a short time, CAN PERMANENTLY DAMAGE YOU EYESIGHT
Eclipse Safety Approved solar filter material Should be used to cover your Equipment and your eyes AT ALL TIMES.
Sunglasses • You should choose sunglasses that: • reduce glare • filter out 99-100% of UV rays • protect your eyes • are comfortable to wear • do not distort colors. Source: Prevent Blindness America.
Eclipse of March 29th 2006 . We will use computer simulations to look at this Eclipse from different vantage points Animations created with Starry Night Pro Plus Software.
Important Solar Eclipses Present - 2030