Solar Eclipses

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Solar Eclipses Notice that both the Sun and the Moon appear in the sky to be about the same size: half of a degree. You can figure this out yourself, because the system has scaled itself. The Sun is around 400 times the size of the Moon in diameter. But, the Moon is about 400 times closer to us than is the Sun. These cancel out distance effects and scale the apparent sizes of the objects in the sky to the same size. Great! This means, geometrically, that if you could line them up one day, you could blot one out with the other. Because of the distances involved, which one would block the other? The Moon would block out the further Sun. What about when the Moon is on the other side of the Earth? The Earth would cast a shadow on the Moon when they were all three lined up. When the Moon blocks the Sun, we call it a solar eclipse. (The other eclipse is when the Sun-Earth- Moon lineup is in effect, and the Earth blocks the Moon. But we want to focus on the solar eclipse....) What would that look like from space? What phase is the Moon for a solar eclipse? It is in New Moon (and conversely in Full Moon during a lunar eclipse. Does the Moon always block the Sun each time it moves into the Sun- Moon-Earth alignment? Do you experience an eclipse of the Sun each month? No. Why not? As it is, the Moon does not orbit in the same plane as the Earth orbits the Sun; the Moon orbits 5 degrees tilted to the Earth's orbital plane. So that small number of degrees is enough to limit the solar eclipses to around once a year. The fact that the Moon’s shadow is so tiny also means that the number of solar eclipses which happen for a certain place are also limited. People who want to view a solar eclipse usually have to travel to go see one. Lunar eclipses, however, are easier to see, since the shadow of the Earth on the Moon is quite large..

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Solar Eclipses, One of Nature’S Most Impressive Sights, Have Fascinated People for Thousands of Years
® World Book Student Database The trusted, student-friendly online reference tool. Name: ____________________________________________________ Date:_________________ World Book Online: Solar eclipses, one of nature’s most impressive sights, have fascinated people for thousands of years. How much do you know about solar eclipses? Answer these questions to find out! Solar Eclipse First, go to www.worldbookonline.com Then, click on “Student.” If prompted, log on with your ID and Password. Find the answers to the questions below by using the “Search” tool. Since this activity is about solar eclipses, you can start by searching the key word “eclipse.” Write the answers on the lines provided or below the question. Find1. A It! solar eclipse takes place when the sun appears to become dark as the _______________ passes between the sun and Earth. 2. A _______________ eclipse occurs when the moon darkens as it passes through Earth’s shadow. 3. During a solar eclipse the moon’s shadow usually moves from west to east across Earth at a speed of about _______________ miles ( _______________ kilometers) per hour. 4. What is the average time the sun is totally darkened during a total solar eclipse? 5. A total solar eclipse can be seen only in certain parts of the world, which lie in the __________________________. © 2017 World Book, Inc. Chicago, Illinois, U.S.A. All rights reserved. World Book and the globe device are trademarks or registered trademarks of World Book, Inc. This webquest may be reproduced without World Book’s permission provided that it is reproduced exactly as published by World Book and is reproduced for entirely non-commercial educational purposes.
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Viewing an Eclipse Safely
ECLIPSES SOLAR an eclipse safely How to observe SOLAR ECLIPSE, OCTOBER 2014, BY LEMAN NORTHWAY Solar eclipses are quite rare and are often a major event. The SOLAR ECLIPSES Moon passes right in front of the Sun, blotting out its disc. Every time a solar eclipse occurs there are various things to look for. However, it is extremely dangerous to just go out and look up. The Sun is so bright that just looking at it can blind you, so you’ll need to prepare beforehand. There are various ways to observe eclipses safely, using both everyday materials and telescopes or binoculars. So read this leaflet Introduction to find out what happens during an eclipse and how you can see all the stages of the event safely. This booklet was written by the Royal Astronomical Society with The Society for Popular Astronomy and is endorsed by the British Astronomical Association The Royal Astronomical The Society for Popular Formed in 1890, the Society, founded in Astronomy is for British Astronomical 1820, encourages and beginners of all ages. Our Association has an promotes the study of aim is to make astronomy international reputation astronomy, solar-system fun, and our magazine, for the quality of science, geophysics and Popular Astronomy, is full its observational closely related branches of information to help and scientific work. of science. you get to know the Membership is open to www.ras.org.uk sky and get involved. We even have a special Young all persons interested in HIGGS-BOSON.COM JOHNSON: PAUL BY D Stargazers section, run by TV’s Lucie Green.
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The Moon and Eclipses
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Solstices & Equinoxes –Precession – Phases of the Moon –Eclipses
Today –Solstices & Equinoxes –Precession –Phases of the Moon –Eclipses • Lunar, Solar –Ancient Astronomy FIRST HOMEWORK DUE NEXT TIME © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley Tropic: Latitude where the sun [just] reaches the zenith at noon on the summer solstice Arctic/Antarctic Circle: Latitude where the sun does not set [just barely] on the summer solstice (like a circumpolar star) nor does it rise on the winter solstice o N 66.5 arctic Ecliptic plane Tropic of Cancer 23.5o Tropic of Capricorn Equator antarctic © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley Seasonal changes are more extreme at high latitudes. Path of the Sun on the summer solstice at the Arctic Circle © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley How does the orientation of Earth’s axis change with time? Precession: • Although the axis seems fixed on human time scales, it actually precesses over about 26,000 years. — Polaris won’t always be the North Star. Earth’s axis wobbles like the axis of a spinning top. © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley • Precession: the orientation of Earth’s axis slowly changes with time: — The tilt remains about 23.5 degrees (so the season pattern is not affected), but Earth has a 26,000 year precession cycle that slowly and subtly changes the orientation of the Earth’s axis. — The discovery of precession is attributed to the Ancient Greek astronomer Hipparchus (c. 280 BC) © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley Lunar phases • Lunar phases are a consequence of the Moon’s 27.3-day orbit around Earth.
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Solar Eclipse and Your Eyes (Continued)
Solar Eclipse and Your Eyes What is a solar eclipse? 211 West Wacker Drive, Suite 1700 A solar eclipse occurs when the moon moves between the sun and the earth. Chicago, Illinois 60606 The moon causes the light of the sun to be blocked from reaching earth, 800.331.2020 casting a shadow on earth. A total solar eclipse is when the moon completely PreventBlindness.org blocks the sun. The sun’s outer atmosphere (called the solar corona) glows around the moon when it is blocking the sun. A partial solar eclipse is when the moon only blocks part of the sun. Viewing a partial solar eclipse can expose your eye to the sun’s rays causing damage to the eye. How can your eyes be affected by a solar eclipse? Exposing your eyes to the sun without proper eye protection during a solar eclipse can cause “eclipse blindness” or retinal burns, also known as solar retinopathy. This exposure to the light can cause damage or even destroy cells in the retina (the back of the eye) that transmit what you see to the brain. This damage can be temporary or permanent and occurs with no pain. It can take a few hours to a few days after viewing the solar eclipse to realize the damage that has occurred. What are the eye symptoms that can occur from looking at a solar eclipse without proper eye protection? • Loss of central vision (solar retinopathy) • Distorted vision • Altered color vision If you notice symptoms after viewing a solar eclipse, seek treatment from an eye care professional.
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Solar Eclipses: Earth Varies Even More Percentage-Wise, Between 357 300 Km and 406 500 Km (In the New Moon Position)
R D Since r ≈ 400 ≈ d , we see that θS ≈ θM . The sun is at one focus of the counterclockwise elliptical orbit of the Earth around the sun. Thus, the distance D between the sun and the Earth actually varies between 147 100 000 km (perihelion, which occurs each year around January 3) and 152 100 000 km (aphelion, which occurs around July 4). The moon’s distance from the center of the Solar Eclipses: Earth varies even more percentage-wise, between 357 300 km and 406 500 km (in the new moon position). Thus, the actual values Geometry, of the angles θS and θM range as follows: Frequency, Cycles ◦ ◦ ◦ ◦ by 0.524 ≤ θS ≤ 0.542 , 0.497 ≤ θM ≤ 0.567 , † ◦ ◦ Hermann Koenig with mean values over time of θS = 0.533 and θM = 0.527 . If the moon does not cover the sun completely, an annular or partial eclipse may result. penumbra Total solar eclipses are spectacular shows in the sky, in par- A R T ticular, if they occur on a bright day around noon. In a narrow r d d s band on Earth, the moon completely obscures the sun and the SUN P MOON EARTH solar corona becomes visible. Sun and moon both appear to the EARTH 1 ◦ observer on Earth to subtend an angle of roughly θ = 2 , even though the radius of the sun is 400 times larger than that of the umbra EARTH moon. By pure chance, the sun is also about 400 times further Figure 2 away from the Earth than the moon.
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W:09/19/18 Eclipses
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2017 Solar Eclipse Will Spend a Great Deal of Time Over Land
2017 Total Solar Eclipse On August 21, 2017, a Total Solar Eclipse will occur along a track running across the Continental USA from Salem, Oregon to Charleston, South Carolina. Simulation Curriculum Corp. Teachable Moment - www.StarryNight.com Introduction .........................................................3 Take it to the Next Level with Starry Night ......................................................................3 2017 Total Solar Eclipse ......................................4 What is a Solar Eclipse .........................................................4 The Total Solar Eclipse of 2017 ............................................7 Safely Watching the Eclipse .................................................9 Solar Eclipses in History .....................................................11 The Saros Cycle ...................................................................14 Solar Eclipse Math .............................................16 Calculating the Speed of the Lunar Shadow on the Earth 16 Calculating the Radius of the Lunar Shadow on the Earth 17 Introduction On August 21, 2017, a Total Solar Eclipse will occur along a track running across the Continental USA from Salem, Oregon to Charleston, South Carolina. At most points along the track, totality will last more than two minutes, peaking at 2 minutes, 41.6 seconds just east of St. Louis, Missouri. Observers south and north of the track will see only a partial eclipse, the degree varying depending on the distance north or south. Take it to the Next Level with Starry Night A highly interactive version of this lesson plan with additional features is available for users of Starry Night software. To find this content in Starry Night open the SkyGuide pane and click on the Teachable Moments or Learning Moments icon depending on which version of the software you own. If you do not own Starry Night, you can still use this document to learn more about the 2017 Total Solar Eclipse.
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Total Solar Eclipse of 2020 Brochure
WILDERNESS TRAVEL SPECIAL EVENTS Total Solar Eclipse of 2020 PROGRAMS IN SOUTH AMERICA & FRENCH POLYNESIA Lakes to Volcanoes Eclipse Adventure Tropical Polynesia Eclipse Cruise Chile & Argentina Hotel-Based Program Ship-Based Program DECEMBER 9-15, 2020 DECEMBER 5-19, 2020 with Dr. Richard Terrile with Jean-Michel Cousteau, Dr. Alex Filippenko, and Lorenzo Sympson Dr. Rick Fienberg, Mark Eddowes Dear Friends, One of the universe’s most beautiful and dramatic events—a total solar eclipse, when the sun, moon and earth are perfectly aligned and darkness washes over earth in the middle of the day—will occur on December 14, 2020. Astronomer David Levy says a total solar eclipse “is a natural event with unnatural consequences. In fact, a total eclipse of the sun has the power to rip through to the core of your being.” If you’ve ever experienced one, you understand exactly what Levy means. And if you haven’t, 2020 is your best chance to find out. Wilderness Travel has offered exclusive eclipse experiences for 25 years in some of the world’s most remote locations, from western Mongolia to the Atacama Desert. For the total solar eclipse of 2020, we are delighted to share two exciting programs. Our land-based program will immerse you in the beautiful lakes and volcanoes region of Chile and Argentina, with an exclusive viewing site on the side of a volcano in Chile, right on the centerline of the eclipse. Our cruise aboard the Paul Gauguin will bring you through some of French Polynesia’s most renowned islands, including the Marquesas, Bora Bora, and Moorea—and for Eclipse Day, we’ll position the ship at an ideal point for promising weather and unusual solar features along the eclipse centerline.
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Great Solar Eclipse of 2017 Source: Theweek.Com, August 5, 2017
1. Mark your confusion. 2. Show evidence of a close reading. 3. Write a 1+ page reflection. The Great Solar Eclipse of 2017 Source: TheWeek.com, August 5, 2017 On Aug. 21, the moon's shadow will roll across the U.S. as tens of millions of Americans witness a total solar eclipse. Here's everything you need to know: Why do total eclipses occur? Occasionally, the moon's elliptical orbit carries it directly between the sun and Earth, placing all three celestial objects in complete alignment. The moon's shadow then falls across Earth's surface, ultimately appearing to blot out the sun entirely. The phenomenon isn't especially rare, occurring somewhere on Earth every 18 months or so. But from any single given spot, a total solar eclipse is observable only once in 375 years. This one will be the first anywhere in the U.S. since 1979, and the first since 1918 to be visible from coast to coast. It will also be the first solar eclipse to be seen only on American soil since 1776. "The path of totality will cross through a whopping 14 states," says astrophysicist Ethan Siegel. "More than 12 million people will get to experience totality without ever leaving their homes." What will eclipse gazers see? It's a gradual process, beginning with first contact — "when the sun and moon 'touch,'" explains NASA heliophysicist Mitzi Adams. "This leads to the partial phase, when it looks like someone is taking increasingly large bites from the sun. Next is the actual eclipse itself, when the sun is totally covered by the moon." All that is visible then is the solar corona, the sun's gaseous halo, which peeks out from the blackness.
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Saros Cycles & Eclipses
Harvest Moon • Full moon closest to the autumnal equinox, and can come anywhere from two weeks before to two weeks after the autumnal equinox. • Northern Hemisphere: 2015 autumnal equinox comes on September 23, so the September 28 full moon counts as the Northern Hemisphere’s Harvest Moon. • This year’s Harvest Moon is the closest and largest full moon of the year. • In autumn, the ecliptic – or path of the sun, moon and planets – makes a narrow angle with the evening horizon, causing the location of the moonrise on the horizon to be farther north along the eastern horizon for several nights in The narrow angle of the ecliptic means the moon rises succession. noticeably farther north on the horizon, from one night to the next. So there is no long period of darkness between sunset and moonrise. Eclipse pairs -- solar and lunar eclipses, in a family of signs on the same axis. 2015 •Pisces-Virgo: solar new moon eclipse on March 20, 2015 in Pisces at 29 degrees, and a solar eclipse Sep 12 in Virgo at 20 degrees. •Aries-Libra family: lunar eclipse in Libra on April 4, at 14 degrees, and lunar eclipse full moon Sep 27 in Aries 5 degrees. 2016 •Lunar full moon eclipse in Libra, on Mar 23 at 3 degrees, which concludes two years of the Libra-Aries family. •Total number of eclipses 6 per family : Pisces-Virgo family ends Feb 26, 2017 •Eclipse move retrograde •Consider the eclipses forming aspects with planets, the sun, moon or ascendant in the natal chart. •The range of the degree for any eclipse in the family insures a wide number of people will feel them in their natal chart.
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Solar Eclipse and Your Eyes (Continued)
Solar Eclipse and Your Eyes What is a solar eclipse? 211 West Wacker Drive, Suite 1700 Chicago, Illinois 60606 A solar eclipse occurs when the moon moves between the sun and the 800.331.2020 earth. The moon causes the light of the sun to be blocked from reaching PreventBlindness.org earth, casting a shadow on earth. A total solar eclipse is when the moon completely blocks the sun and a partial solar eclipse with when the moon only blocks part of the sun. The sun’s outer atmosphere (called the solar corona) glows around the moon when it is blocking the sun. It is this glow of the sun’s solar corona that can cause damage to your eye. How can your eyes be affected by a solar eclipse? Exposing your eyes to the sun without proper eye protection during a solar eclipse can cause “eclipse blindness” or retinal burns, also known as solar retinopathy. This exposure to the light can cause damage or even destroy cells in the retina (the back of the eye) that transmit what you see to the brain. This damage can be temporary or permanent and occurs with no pain. It can take a few hours to a few days after viewing the solar eclipse to realize the damage that has occurred. What are the eye symptoms that can occur from looking at a solar eclipse without proper eye protection? • Loss of central vision (solar retinopathy) • Distorted vision • Altered color vision If you notice symptoms after viewing a solar eclipse, seek treatment from an eye care professional.
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