Sun Earth Moon Eclipses and Tides

Sun, Earth, and Moon:

Sun, Earth, and Moon Lunar Phases Eclipses Tides Celestial Motion

Phases of the Moon:

Phases of the Moon The appearance or shape of the Moon gradually changes through the course of a month. This cycle - the cycle of lunar phases, may be explained if we state the following: The Moon is spherical in shape. The Moon is not self-luminous, but rather reflects the light of the distant Sun. The Moon circles the Earth once per month.

Fun Facts for Lunatics:

Fun Facts for Lunatics Lunar Libration: The spin of the Moon proceeds at a uniform rate while the orbit is at a slightly nonuniform rate. The spin can get a little bit ahead or behind the orbit. Hence the face of the Moon presented to the Earth rocks back and forth by some 6° each month, a phenomenon known as longitudinal libration. The Moon's orbital plane: The plane of the Moon's orbit is tilted by 5° with respect to that of the Earth's orbit. Hence the rotation axis of the Earth is tilted with respect to the Moon's orbital plane by an amount within 5° of 23.5°, depending on whether the two tilts are in or out of phase. The length of time between moonrise and moonset for, say, a full Moon varies with the season as well. (Also, note the phasing between the two tilts varies continually with time, going full circle every 18.6 years.) The variable speed of the Moon: Like the Earth, the Moon moves in a slightly elliptical orbit as well. Hence, while the average time elapsed from, say, New Moon to First Quarter is 7.4 days, the actual time can be as short as 6.7 days near perigee (closest approach to Earth) or as long as 8.1 days near apogee.

Moon at Perigee and Apogee:

Moon at Perigee and Apogee Distance: 359,861 km Distance: 405,948 km

Eclipses:

Eclipses Celestial bodies are always “eclipsing” or moving in front of each other. Eclipses occur at predictable intervals. Other names include: Transits and Occultations. Solar Eclipses can be total, partial, or annular

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Moon's shadow on Earth taken by French cosmonaut Jean-Pierre Haigneré aboard the Mir

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" Here lie the bodies of Ho and Hi, Whose fate, though sad, is risible; Being slain because they could not spy Th' eclipse which was invisible. " Author unknown: Said to refer to the Chinese eclipse of 2136 BC or 2159 BC. " On the day of the new moon, in the month of Hiyar, the Sun was put to shame, and went down in the daytime, with Mars in attendance. " One of the earliest written records of an eclipse of the Sun, on 3 May 1375 BC, found in the city of Ugarit in Mesopotamia.(Reprinted, from Chasing the Shadow , copyright 1994 by Joel K Harris and Richard L Talcott , by permission of Kalmbach Publishing Co. " If the Sun at its rising is like a crescent and wears a crown like the Moon: the king wll capture his enemy's land; evil will leave the land, and (the land) will experience good . . . " Refers to a solar eclipse of 27 May 669 BC. Rasil the older, Babylonian scribe to the king. Quoted in Historical Eclipses and Earth's Rotation , by F Richard Stephenson, Cambridge University Press, 1997, page 125. " Nothing can be surprising any more or impossible or miraculous, now that Zeus, father of the Olympians has made night out of noonday, hiding the bright sunlight, and . . . fear has come upon mankind. After this, men can believe anything, expect anything. Don't any of you be surprised in future if land beasts change places with dolphins and go to live in their salty pastures, and get to like the sounding waves of the sea more than the land, while the dolphins prefer the mountains. " May refer to a total solar eclipse of 6 April 648 BC. Archilochus, Greek poet (c680-640 BC) Quoted in Historical Eclipses and Earth's Rotation , by F Richard Stephenson, Cambridge University Press, 1997, page 338. Partly quoted in Encyclopaedia Britannica CD 98 . ECLIPSE QUOTES

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When the moon is new or full, the gravitational forces of the sun and moon are pulling at the same side of the earth. (See the diagram below.) This occurrence creates the extra large "spring" tides. When the moon is at first and third quarter, the gravitational forces of the sun and moon are pulling at 90 degrees from each other. (see the diagram below.) This occurrence yeilds little net tides called neap tides.

More Fun Tidal Tales….:

More Fun Tidal Tales…. Every few years people that measure such things (chronologists?) need to add a leap second to the year. The Earth's rotation is decelerating at a rate of about 0.002 seconds per day per century. The Earth will eventually stop slowing down – when it’s rotation is equal to the moon’s orbital period !!! The Proxigean Tide occurs when the Moon is at its closest point in its orbit to the Earth and in its New or Full Moon phase. At this time, its tidal effect on the Earth is maximum. The times when this will happen often coincide with major coastal flooding events. Between 1997 and 2020 there will be 102 times when this will happen. The moon shows the same face to the Earth because it was deformed by Earth’s gravity when it was still molten. Earth uses this “memory” to grab the moon and slow its spin rate down. WHY ?

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MERCURY Mercury is the innermost and smallest planet in the Solar System , [a] orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt . It completes three rotations about its axis for every two orbits. The perihelion of Mercury's orbit precesses around the Sun at an excess of 43 arcseconds per century.

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VENUS Venus is classified as a terrestrial planet and it is sometimes called Earth's "sister planet" (see below) due to the similar size, gravity, and bulk composition. Venus is covered with an opaque layer of highly reflective clouds of sulfuric acid , preventing its surface from being seen from space in visible light . Venus has the densest atmosphere of all the terrestrial planets in the solar system , consisting mostly of carbon dioxide .

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EARTH Earth (or the Earth ) is the third planet from the Sun and the densest and fifth-largest of the eight planets in the Solar System . It is also the largest of the Solar System's four terrestrial planets .

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MARS Mars is the fourth planet from the Sun in the Solar System . The planet is named after the Roman god of war , Mars . It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance

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JUPITER Jupiter is the fifth planet from the Sun and the largest planet within the Solar System . [13] It is a gas giant with a mass slightly less than one-thousandth of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn , Uranus and Neptune . Together, these four planets are sometimes referred to as the Jovian or outer planets.

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SATURN Saturn has an average radius about 9 times larger than the Earth's . [12] While only 1/8 the average density of Earth, due to its larger volume , Saturn's mass is just over 95 times greater than earth

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URANUS Uranus is the seventh planet from the Sun . It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System . It is named after the ancient Greek deity of the sky Uranus ( Ancient Greek : Οὐρανός ), the father of Cronus ( Saturn ) and grandfather of Zeus ( Jupiter ). Though it is visible to the naked eye like the five classical planets , it was never recognized as a planet by ancient observers because of its dimness and slow orbit. [

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NEPTUNE Neptune is the eighth and farthest planet from the Sun in the Solar System . Named for the Roman god of the sea , it is the fourth-largest planet by diameter and the third-largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus , which is 15 times the mass of Earth but not as dense

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THE SOLAR SYSTEM

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DONE BY: MOHAMMED MUJTABA KHAN (V-H)