Viewing an Eclipse Safely
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Illuminating Eclipses: Astronomy and Chronology in King Lear
Brief Chronicles Vol. II (2010) 32 Illuminating Eclipses: Astronomy and Chronology in King Lear Hanno Wember ohann Gottfried Herder wrote his famous essay Shakespeare in 1772. He was (as Wieland, Lessing and, of course, Goethe and Schiller) one of the 18th century German writers “who first embraced Shakespeare and welcomed his Jgenius as a dramatist.”1 In his 1980 introduction to Herder’s essay, Konrad Nussbächer wrote: “Shakespeare is not, as it appeared in the 18th century, a natural genius growing up in the wild, but a highly cultured, artful Renaissance poet and practitioner of the stage.” Astronomy was one of the liberal arts and sciences a “highly cultured” man of Renaissance England was expected to know. This essay will review a few illuminating examples of Shakespeare’s profound knowledge of astronomy, and will examine a new astronomical reference that could shed significant new light on Shakespearean chronology. Shakespeare’s Astronomy In many regards Shakespeare had a better knowledge of the relationship between the moon and the tides2 than his distinguished contemporary Galileo (1564 - 1642), who tried to explain the tides by the two motions of the earth, correlating to the day and the year.3 This was an erroneous explanation for ebb and flow. But while Galileo refused to acknowledge any tidal influence of the moon, Bernardo knew better, referring to the moon as the Brief Chronicles Vol. II (2010) 33 moist star Upon whose influence Neptune’s empire stands (Hamlet, I.1.135)4 To Prince Henry, likewise, the moon commands the tides: The fortune of us that are moon’s men doth ebb and flow like the sea, being governed as the sea is by the moon…..Now in as low an ebb as the foot of the ladder, and by and by in as high a flow as the ridge of the gallows. -
Variation of Secondary Cosmic Gamma Ray Flux During Lunar Eclipse
Variation of secondary cosmic gamma ray flux during lunar eclipse S. Roy* , S. Chatterjee , S. Chakraborty** , S. Biswas , S. Das , S. K. Ghosh , S. Raha Department of Physics (CAPSS), Bose Institute, Kolkata, India. E-mail: [email protected] Introduction Astronomical events such as Solar eclipses and Lunar eclipses provide the opportunity for studying the disturbance produced in the atmosphere and its effect on cosmic ray intensity. There are earlier reports on decrease in secondary cosmic gamma ray (SCGR) flux during solar eclipse and enhancement of the same during lunar eclipse [1-4]. We have measured the variation of SCGR flux during two lunar eclipses that took place in India in the year 2018, one on 31st of January and the other on 27th of July. Both the measurements have been carried out in the Detector laboratory of Bose Institute, Kolkata, India, using NaI (Tl) scintillator detector. We observed slight increment of SCGR during the lunar eclipse of January. We did not observe any significant changes in SCGR during lunar eclipse of July. Experimental Setup ❖ NaI(Tl) scintillator detector is used. Size of the crystal: 5.1cm × 5.1cm ❖ Gamma ray sources used for detector calibration: 137Cs (662 keV), ❖ PMT bias: +600V. Signals are amplified and shaped before sending 60Co (1173 keV and 1332 keV) and 22Na (551 keV) them to MCA for energy spectrum accumulation ORTEC-556 ORTEC-671 Schematic of the signal processing electronics Picture of the experimental setup Gamma ray spectra with different configurations of lead shielding ADC -
Telescopes and Binoculars
Continuing Education Course Approved by the American Board of Opticianry Telescopes and Binoculars National Academy of Opticianry 8401 Corporate Drive #605 Landover, MD 20785 800-229-4828 phone 301-577-3880 fax www.nao.org Copyright© 2015 by the National Academy of Opticianry. All rights reserved. No part of this text may be reproduced without permission in writing from the publisher. 2 National Academy of Opticianry PREFACE: This continuing education course was prepared under the auspices of the National Academy of Opticianry and is designed to be convenient, cost effective and practical for the Optician. The skills and knowledge required to practice the profession of Opticianry will continue to change in the future as advances in technology are applied to the eye care specialty. Higher rates of obsolescence will result in an increased tempo of change as well as knowledge to meet these changes. The National Academy of Opticianry recognizes the need to provide a Continuing Education Program for all Opticians. This course has been developed as a part of the overall program to enable Opticians to develop and improve their technical knowledge and skills in their chosen profession. The National Academy of Opticianry INSTRUCTIONS: Read and study the material. After you feel that you understand the material thoroughly take the test following the instructions given at the beginning of the test. Upon completion of the test, mail the answer sheet to the National Academy of Opticianry, 8401 Corporate Drive, Suite 605, Landover, Maryland 20785 or fax it to 301-577-3880. Be sure you complete the evaluation form on the answer sheet. -
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. -
Astronomical Binoculars
30˚E 15˚E OWNER’S MANUAL ASTRONOMICAL BINOCULARS ZHUMELL 20X80 SUPERGIANT ASTRONOMICAL BINOCULARS 0˚ 15˚W 75˚W 60˚W 30˚W 45˚W Zhumell customers know that there are plenty of ways to experience the world. They also understand that, however you choose to explore it, the best experience is one that fully immerses you in the world’s most striking details. That’s where our optics products come in. We strive to put high-performance products in the hands of our customers so that they can experience the world up close, with their own eyes. With Zhumell, you get field-tested, precision-crafted optics at the best possible value. So even if you’re just starting out as an amateur birder or astronomer, you don’t have to settle for entry-level products. Zhumell customers enjoy life’s pursuits, hobbies, and adventures in rich, colorful detail- the kind of detail that only high-performance optics can produce. At Zhumell, we design our binoculars, telescopes, and spotting scopes for discerning, price-conscious users who are uncompromising on quality. If you’re looking for accessibly priced optics that will bring your world within reach, you’re looking for Zhumell. Enjoy the view. 2 ENJOYING YOUR ZHUMELL ASTRONOMICAL BINOCULARS 1. Caring For Your Binoculars 2. Using Your Binoculars i. Tripod Mounting ii. Interpupillary Distance iii. Center and Diopter Focus 3. Terrestrial and Astronomical Viewing 4. Astronomical Observation Tips i. Selecting a Viewing Site ii. Seeing and Transparency iii. Dark-Adapting iv. Tracking Celestial Objects 5. Cool Views i. The Moon ii. -
1986Aj 92.120Id the Astronomical Journal Volume 92, Number 5 November 1986 Modeling Pluto-Charon Mutual Eclipse Events. I. First
THE ASTRONOMICAL JOURNAL VOLUME 92, NUMBER 5 NOVEMBER 1986 92.120ID MODELING PLUTO-CHARON MUTUAL ECLIPSE EVENTS. I. FIRST-ORDER MODELS R. Scott Dunbar and Edward F. Tedesco Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 1986AJ Received 29 May 1986; revised 7August 1986 ABSTRACT We present numerical and analytical models describing the light curves resulting from mutual events between close planetary binaries, with particular application to the Pluto-Charon system. These models are referred to as “first-order” models because they incorporate the effects of shadowing in such sys- tems, in contrast to “zeroth-order” models, which do not include shadowing. The shadows cast between close binaries of similar size (as in the case of Pluto and Charon) can be treated as extensions of the eclipsing bodies themselves at small solar phase angles. Shadowing plays a major role in the morphology of mutual event light curves. The numerical approach is a straightforward, but computationally inten- sive, discrete-element integration. The analytical approach uses a conceptually simple model of three circular disks, representing the planet, satellite, and shadow, and computes the complex geometric relationship among these three disks to obtain the eclipse magnitude at each time step. The results of the two models agree to well within the expected light-curve measurement error. A preliminary model fit to the depths of five mutual eclipse events observed in 1985 and 1986 gives eclipse light-curve-derived estimates of the orbit radius C = 16.5 + 0.5 Pluto radii, the radius ratio B0 = 0.65 + 0.03, and the Charon:Pluto albedo ratio K — 0.55 + 0.15. -
Solar and Lunar Eclipses Reading
Eclipses What would you think if you were walking home from school on a sunny afternoon and the sun began to disappear? Would you be frightened? On rare occasions, the moon completely blocks the sun. The sky grows as dark as night even in the middle of a clear day. The air gets cool and the sky becomes an eerie color. If you don’t know what is happening, you can become very frightened. The moon doesn’t usually go directly between Earth and the sun or directly behind Earth. As the diagram below shows, the moon’s orbit around Earth is slightly tilted with respect to Earth’s orbit around the sun. As a result, in most months the moon revolves completely around Earth without the moon moving into Earth’s shadow or the moon’s shadow hitting Earth. When the moon’s shadow hits Earth or Earth’s shadow hits the moon, an eclipse occurs. An eclipse (ih klips) occurs when an object in space comes between the sun and a third object, and casts a shadow on that object. There are two types of eclipses: solar eclipses and lunar eclipses. (The words solar and lunar come from the Latin words for “sun” and “moon.”) The Tilt of the Moon’s Orbit The moon’s orbit is tilted with respect to Earth’s orbit. So the moon rarely goes directly between Earth and the sun. Solar Eclipses During a new moon, the moon is almost exactly between Earth and the sun. But most months, as you have seen, the moon travels a little above or below the sun in the sky. -
Can You Spot the Sunspots?
Spot the Sunspots Can you spot the sunspots? Description Use binoculars or a telescope to identify and track sunspots. You’ll need a bright sunny day. Age Level: 10 and up Materials • two sheets of bright • Do not use binoculars whose white paper larger, objective lenses are 50 • a book mm or wider in diameter. • tape • Binoculars are usually described • binoculars or a telescope by numbers like 7 x 35; the larger • tripod number is the diameter in mm of • pencil the objective lenses. • piece of cardboard, • Some binoculars cannot be easily roughly 30 cm x 30 cm attached to a tripod. • scissors • You might need to use rubber • thick piece of paper, roughly bands or tape to safely hold the 10 cm x 10 cm (optional) binoculars on the tripod. • rubber bands (optional) Time Safety Preparation: 5 minutes Do not look directly at the sun with your eyes, Activity: 15 minutes through binoculars, or through a telescope! Do not Cleanup: 5 minutes leave binoculars or a telescope unattended, since the optics can be damaged by too much Sun exposure. 1 If you’re using binoculars, cover one of the objective (larger) lenses with either a lens cap or thick piece of folded paper (use tape, attached to the body of the binoculars, to hold the paper in position). If using a telescope, cover the finderscope the same way. This ensures that only a single image of the Sun is created. Next, tape one piece of paper to a book to make a stiff writing surface. If using binoculars, trace both of the larger, objective lenses in the middle of the piece of cardboard. -
Nikon Binocular Handbook
THE COMPLETE BINOCULAR HANDBOOK While Nikon engineers of semiconductor-manufactur- FINDING THE ing equipment employ our optics to create the world’s CONTENTS PERFECT BINOCULAR most precise instrumentation. For Nikon, delivering a peerless vision is second nature, strengthened over 4 BINOCULAR OPTICS 101 ZOOM BINOCULARS the decades through constant application. At Nikon WHAT “WATERPROOF” REALLY MEANS FOR YOUR NEEDS 5 THE RELATIONSHIP BETWEEN POWER, Sport Optics, our mission is not just to meet your THE DESIGN EYE RELIEF, AND FIELD OF VIEW The old adage “the better you understand some- PORRO PRISM BINOCULARS demands, but to exceed your expectations. ROOF PRISM BINOCULARS thing—the more you’ll appreciate it” is especially true 12-14 WHERE QUALITY AND with optics. Nikon’s goal in producing this guide is to 6-11 THE NUMBERS COUNT QUANTITY COUNT not only help you understand optics, but also the EYE RELIEF/EYECUP USAGE LENS COATINGS EXIT PUPIL ABERRATIONS difference a quality optic can make in your appre- REAL FIELD OF VIEW ED GLASS AND SECONDARY SPECTRUMS ciation and intensity of every rare, special and daily APPARENT FIELD OF VIEW viewing experience. FIELD OF VIEW AT 1000 METERS 15-17 HOW TO CHOOSE FIELD FLATTENING (SUPER-WIDE) SELECTING A BINOCULAR BASED Nikon’s WX BINOCULAR UPON INTENDED APPLICATION LIGHT DELIVERY RESOLUTION 18-19 BINOCULAR OPTICS INTERPUPILLARY DISTANCE GLOSSARY DIOPTER ADJUSTMENT FOCUSING MECHANISMS INTERNAL ANTIREFLECTION OPTICS FIRST The guiding principle behind every Nikon since 1917 product has always been to engineer it from the inside out. By creating an optical system specific to the function of each product, Nikon can better match the product attri- butes specifically to the needs of the user. -
The Moon and Eclipses
Lecture 10 The Moon and Eclipses Jiong Qiu, MSU Physics Department Guiding Questions 1. Why does the Moon keep the same face to us? 2. Is the Moon completely covered with craters? What is the difference between highlands and maria? 3. Does the Moon’s interior have a similar structure to the interior of the Earth? 4. Why does the Moon go through phases? At a given phase, when does the Moon rise or set with respect to the Sun? 5. What is the difference between a lunar eclipse and a solar eclipse? During what phases do they occur? 6. How often do lunar eclipses happen? When one is taking place, where do you have to be to see it? 7. How often do solar eclipses happen? Why are they visible only from certain special locations on Earth? 10.1 Introduction The moon looks 14% bigger at perigee than at apogee. The Moon wobbles. 59% of its surface can be seen from the Earth. The Moon can not hold the atmosphere The Moon does NOT have an atmosphere and the Moon does NOT have liquid water. Q: what factors determine the presence of an atmosphere? The Moon probably formed from debris cast into space when a huge planetesimal struck the proto-Earth. 10.2 Exploration of the Moon Unmanned exploration: 1950, Lunas 1-3 -- 1960s, Ranger -- 1966-67, Lunar Orbiters -- 1966-68, Surveyors (first soft landing) -- 1966-76, Lunas 9-24 (soft landing) -- 1989-93, Galileo -- 1994, Clementine -- 1998, Lunar Prospector Achievement: high-resolution lunar surface images; surface composition; evidence of ice patches around the south pole. -
Hide & Seek Moon
Hide & Seek Moon Children use binoculars to search for small items that an astronaut lost while walking on the Moon. The Moon is pictured on a banner hanging a short distance away. 15 minutes Drop-in 1–4 children at a time Content Learning Goals Materials • Children notice that binoculars make distant objects • Moon Banner appear closer/bigger. • Child-friendly binoculars* • Children begin to understand that binoculars help us • Small black & white images of items to tape see more detail in distant objects. to the Moon (page 7) • Astronaut sign (page 8) Optional: • Photo of the Moon (page 9) • Markers Science Practices • Children observe changes in how objects appear (bigger/closer) when using binoculars. • Children use a tool to better see the small images. SET-UP • Hang the Moon banner on a wall. • Cut out the pictures of the ten items the astronaut lost (page 7). Tape them to the Moon on the banner. • Place a short table or bench with one or more sets of binoculars about 10–12 feet from the wall with nothing obstructing the view of the Moon. Try to choose a distance such that it is difficult to recognize the items with the unaided eye, but easy with the binoculars, keeping in mind young children have sharper eyesight than adults. The ideal distance will depend on the lighting in the room. • For a drop-in program, place the astronaut sign (see page 8) on the table for parents to read to their children. * We recommend using binoculars that are visually appealing to children, properly sized for their small faces, intuitive to use, and have quality optics for a clear view. -
4.4 Total Internal Reflection
n 1:33 sin θ = water sin θ = sin 35◦ ; air n water 1:00 air i.e. ◦ θair = 49:7 : Thus, the height above the horizon is ◦ ◦ θ = 90 θair = 40:3 : (4.7) − Because the sun is far away from the fisherman and the diver, the fisherman will see the sun at the same angle above the horizon. 4.4 Total Internal Reflection Suppose that a light ray moves from a medium of refractive index n1 to one in which n1 > n2, e.g. glass-to-air, where n1 = 1:50 and n2 = 1:0003. ◦ If the angle of incidence θ1 = 10 , then by Snell's law, • n 1:50 θ = sin−1 1 sin θ = sin−1 sin 10◦ 2 n 1 1:0003 2 = sin−1 (0:2604) = 15:1◦ : ◦ If the angle of incidence is θ1 = 50 , then by Snell's law, • n 1:50 θ = sin−1 1 sin θ = sin−1 sin 50◦ 2 n 1 1:0003 2 = sin−1 (1:1487) =??? : ◦ So when θ1 = 50 , we have a problem: Mathematically: the angle θ2 cannot be computed since sin θ2 > 1. • 142 Physically: the ray is unable to refract through the boundary. Instead, • 100% of the light reflects from the boundary back into the prism. This process is known as total internal reflection (TIR). Figure 8672 shows several rays leaving a point source in a medium with re- fractive index n1. Figure 86: The refraction and reflection of light rays with increasing angle of incidence. The medium on the other side of the boundary has n2 < n1.