DOCSLIB.ORG

Pocket Planetarium 3C V8N2.W2

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Pocket Planetarium 3C V8N2.W2 Volume 8 # Number 2 Spring 2004 PocketThe Planetarium Astronomical Information Newsletter of the Planétarium de Montréal The Starry Sky — Spring 2004 R T H O N CEPHEUS Deneb PERSEUS CASSIOPEIA CYGNUS MINOR Capella LYRA URSA URSA Polaris Venus DRACO Vega AURIGA 30/04 Mars 30/04 BOREALIS CORONA HERCULES Saturn Castor 30/04 E GEMINI URSA T A MAJOR May 24 S S May 20 E T OPHIUCHUS Cor Caroli Pollux May 16 BOÖTES W CANES May 14 VENATICI May 12 Procyon CANIS T MINOR Arctur A E SERPENS LEO CANCER N us t Regulus May 10 e Map: Marc Jobin / Planétarium de Montréal m o Jupiter C May 8 May 6 VIRGO June 4June 2May 31May 29 May 26 May 25 LIBRA Spica Comet LINEAR CORVUS HYDRA This Star Map is Accurate on… HYDRA (Eastern Daylight Time, except where mentioned otherwise) How to Use this Map March 21 at midnight EST The above map represents the April 6 at midnight night sky as it appears at the indicated April 21 at 11 p.m. times, and remains usable several hours SOUTH May 6 at 10 p.m. before and after.. Hold the map up to the sky May 21 at 9 p.m. in front of you and turn it so the direction you are facing appears at the bottom. Lines iden- Phases of the Moon tify the contellations. The light band outlines the Milky way. (Eastern Daylight Savings Time) except * = Eastern Standard Time) Full moon Last quarter Seasonal Milestones March 6 at 18:14* March 13 at 16:01* April 5 at 7:03 April 11 at 23:46 The spring equinox occurs on March 20 at May 4 at 16:33 May 11 at 7:04 01:49. The summer solstice will take place June 3 at 0:20 June 9 at 16:02 on June 20 at 20:57 EDT. Spring 2004 will New moon First quarter last 92d 18h 08m. planetarium.montreal.qc.ca March 20 at 17:41* March 28 at 18:48* On the night of April 3 to 4, we April 19 at 9:21 April 27 at 13:32 switch to Daylight Time: Clocks move May 19 at 0:52 May 27 at 3:57 ahead one hour. June 17 at 16:27 June 25 at 15:08 The Pocket Planetarium # 2 Spring 2004 The Sky This Spring Winter’s planetary parade continues this spring, featuring Venus, Mars, Jupiter and Saturn. And a brief appearance by Mercury provides a rare opportunity to see all five “naked-eye” planets at once. But among this star-studded retinue, Venus definitely outshines them all. Venus steals the show known as a “solar transit” (see page 4). by nightfall, so the optimum time for It should come as no surprise that Venus certainly captures the eye, observing it gets earlier and earlier. At Venus is the third brightest celestial but through a small telescope it offers a the end of March, Jupiter culminates in object — surpassed only by the Sun truly fascinating show. In fact, the south at about 22:30. By the begin- and Moon. Throughout winter Venus the planet’s changing ning of May, the planet has already was the dazzling “evening star” — the March 31 aspects are easy to observe. culminated at twilight’s end, and is first star-like object to appear in the Because Venus’ orbit brings then best observed right after dark. west at twilight — and it will continue it closer to Earth this spring, Jupiter is another choice target for to grace the sky until May. its apparent diameter will telescopes. Even small instruments This apparition of Venus is increase dramatically. At the same time, reveal the four moons discovered by extremely favorable. Toward the end of the planet’s illuminated portion Galileo (the total number now surpass- March, the planet appears 46 degrees will change from a quarter May 1st es sixty!) and some of the planet’s from the Sun — its greatest solar sepa- phase to a thin crescent. atmospheric cloud bands. ration. On top of that, the line joining In just a month-and-a- The Moon’s monthly orbit regularly Venus and the Sun forms a very steep half, a spectacular transfor- carries it near the giant planet in the sky. angle to the horizon. As a result, Venus mation unfolds! At the end of On the night of April 2 to 3, the gibbous is very high in the evening sky at the March, Venus’ disk is exactly half lit Moon is situated 3 1/2 degrees to the left beginning of spring. In fact, during this and measures 24 arcseconds of Jupiter; on April 29, the Moon is 3 1 period, the dazzling planet sets 4 /2 May 15 across. However, by mid- degrees above the planet; and finally, hours after the Sun! May its apparent size dou- the first quarter Moon is near Jupiter While the winter constellations drift bles to 47 arcseconds, and once again on May 26 and 27. progressively toward the western hori- it takes on a classical cres- zon, Venus moves eastward among the cent shape with two distinct Saturn — one last look stars. This explains why the evening “horns.” This spring, Saturn is situated at the star seems to remain at about the same During the waning days of center of the constellation Gemini, just place in the sky night after night. Along May, Venus grows even May 31 to the upper left of Orion. Right now the way, Venus passes the Pleiades — a larger: As its crescent gets Saturn’s rings are wide open, which magnificent star cluster in Taurus. On progressively thinner, its makes it — without doubt — one of April 2 and 3, the two objects are less disk swells to nearly one the most beautiful sights in the sky. A than a degree apart. If you follow this minute of arc (1/60th of a small telescope reveals the rings easily, celestial encounter you can see how degree)! Unfortunately, by this time but a larger instrument truly shows the much Venus moves from one evening Venus is very close to the horizon, and planet in all its glory. to the next. observing conditions deteriorate rapidly. Don’t wait too long! In May, con- In fact, Venus’ motion also brings it On March 24, at nightfall, the cres- ditions for observing the ringed planet seemingly closer to Mars: By April 25, cent Moon is just two degrees to the deteriorate rapidly. By then it is too low the two planets are just 5 1/2 degrees left of Venus — a spectacular sight not on the horizon to view clearly, and by apart. But then, Venus loses ground to be missed! The Moon also appears early June it disappears completely in and slips from its celestial perch — near Venus on April 22 and 23, and the Sun’s glare. slowly at first and then progressively again on May 20 and 21, but on these The crescent Moon is near Saturn faster. In May, the evening star quickly occasions the two are not nearly as on the evenings of March 28, April 24 loses altitude and disappears in the close. and 25, and again on May 22. On this Sun’s glare by the end of the month. A final occasion, Mars is also in the pic- few days later, on June 8, Venus is in Jupiter at its best ture: The two planets are just 1 1/2 inferior conjunction. At this point the Jupiter spends the coming months degrees apart on May 25. planet’s orbit carries it exactly between beneath the constellation Leo. The the Sun and Earth, which will result in a giant planet was in opposition on Mars — engulfed by the Sun rare (and widely anticipated) event March 3. This spring it has already risen Mars remains visible this spring Spring 2004 The Pocket Planetarium # 3 And Mercury Makes Five! Mercury is the hardest planet to Until about April 6, the five plan- events are certainly not common. observe with the naked eye: It’s close ets known to ancient observers can be Face west about 45 minutes after to the Sun and never far above the seen in the evening sky at once. While sunset. Brilliant Venus is, by far, the horizon. As a result, the tiny planet is not considered extremely rare, such easiest to identify. But if the sky is only visible at dusk or dawn, and only clear and unobstructed, you’ll also March 31, at dusk for brief periods of time. Jupiter one hour after sunset notice Mercury somewhat closer to However, as spring gets under- Saturn Capella the horizon and slightly to the right. way, Mercury favors us with an excel- Mars is above Venus and to the left, lent apparition. To see it, just look while Saturn is higher still, about two toward the western horizon, from thirds of the way between the horizon March 23 to April 6, about half-an- and the zenith. Note that the four hour after sunset. The tiny planet will Betelgeuse planets fall, more-or-less, on the same be brighter toward the beginning of Mars imaginary line — a fact that will no this period. A quick word of advice: An Aldebaran The Pleiades doubt help you with your search. ordinary pair of binoculars can help To locate the fifth planet, you’ll you find Mercury in the glow of twi- Venus light. have to stand with your back to the first four. Jupiter is the very bright Five planets at once “star” shining in the east.
Load more

Recommended publications
  • TAKE-HOME EXP. # 1 Naked-Eye Observations of Stars and Planets
    TAKE-HOME EXP. # 1 Naked-Eye Observations of Stars and Planets Naked-eye observations of some of the brightest stars, constellations, and planets can help us locate our place in the universe. Such observations—plus our imaginations—allow us to actively participate in the movements of the universe. During the last few thousand years, what humans have said about the universe based on naked-eye observations of the night and day skies reveals the tentativeness of physical models based solely on sensory perception. Create, in your mind's eye, the fixed celestial sphere. See yourself standing on the Earth at Observer's the center of this sphere. As you make the zenith + star-pattern drawings of this experiment, your perception may argue that the entire sphere of fixed star patterns is moving around the Earth and you. To break that illusion, you probably have to consciously shift your frame of º reference—your mental viewpoint, in this 50 up from the horizon case— to a point far above the Earth. From South there you can watch the globe of Earth slowly Observer on local horizon plane rotate you , while the universe remains essentially stationary during your viewing It is you that turns slowly underneath a fixed and unchanging pattern of lights. Naked eye observations and imagination has led to constellation names like "Big Bear" or "Big Dipper". These names don't change anything physically —except, and very importantly, they aid humans' memory and use of star patterns. A. Overview This experiment involves going outside to a location where you can observe a simple pattern of stars, including at least 2, but preferably 3 or 4 stars.
    [Show full text]
  • The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 a Good Way to Start – Find North
    The expression "dog days" refers to the period from July 3 through Aug. 11 when our brightest night star, SIRIUS (aka the dog star), rises in conjunction* with the sun. Conjunction, in astronomy, is defined as the apparent meeting or passing of two celestial bodies. TAAS Fabulous Fifty A program for those new to astronomy Friday Evening, July 20, 2018, 8:00 pm All TAAS and other new and not so new astronomers are welcome. What is the TAAS Fabulous 50 Program? It is a set of 4 meetings spread across a calendar year in which a beginner to astronomy learns to locate 50 of the most prominent night sky objects visible to the naked eye. These include stars, constellations, asterisms, and Messier objects. Methodology 1. Meeting dates for each season in year 2018 Winter Jan 19 Spring Apr 20 Summer Jul 20 Fall Oct 19 2. Locate the brightest and easiest to observe stars and associated constellations 3. Add new prominent constellations for each season Tonight’s Schedule 8:00 pm – We meet inside for a slide presentation overview of the Summer sky. 8:40 pm – View night sky outside The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 A Good Way to Start – Find North Polaris North Star Polaris is about the 50th brightest star. It appears isolated making it easy to identify. Circumpolar Stars Polaris Horizon Line Albuquerque -- 35° N Circumpolar Stars Capella the Goat Star AS THE WORLD TURNS The Circle of Perpetual Apparition for Albuquerque Deneb 1 URSA MINOR 2 3 2 URSA MAJOR & Vega BIG DIPPER 1 3 Draco 4 Camelopardalis 6 4 Deneb 5 CASSIOPEIA 5 6 Cepheus Capella the Goat Star 2 3 1 Draco Ursa Minor Ursa Major 6 Camelopardalis 4 Cassiopeia 5 Cepheus Clock and Calendar A single map of the stars can show the places of the stars at different hours and months of the year in consequence of the earth’s two primary movements: Daily Clock The rotation of the earth on it's own axis amounts to 360 degrees in 24 hours, or 15 degrees per hour (360/24).
    [Show full text]
  • NATURE [Nov. 22, R877 Addressed to Dr
    66 NATURE [Nov. 22, r877 addressed to Dr. J annetaz, Secretaire-general, rue des the accuracy to which observers had attained. by the old Grands Augustins, 7, Paris, France; and all moneys sent method; but in the rude nature of the telescope itself in to Dr. Bioche, at the same address. the early times, before the introductio.n of the micrometer ; the modern accuracy has been arnved at step by step. THE MODERN TELESCOPE HE gain to astronomy from the discovery of the T telescope has been twofold. We. first, the. gain to physical astronomy from the magmficauon of obJects; and secondly, the gain to astronomy of position from the magnification, so to speak, of space, which enables minute ·portions of it to be most accurately quantified. FtG. 1.-A portion of the constellation Gemini seen with the naked eye. Looking back, nothing is more curious in the history of astronomy than the rooted objection which Revel and Let us see what the telescope does for us in the others showed to apply the telescope to the pointers and domain of that grand physical astronomy which deals pinnules of the instruments used in their day ; but doubt- with the number and appearances of the various bodies less we must look for the explanation of this not only in 1 which people space . FJG. 2.-The same region, as seeu through a large telescope. Let us, to begin with, try to see how the telescope helps the moon with a telescope of that magnifying power pretty us in the matter of observations of the sun.
    [Show full text]
  • 10 Tips for Moon Watchers Moon’S Brightness Are to Use High Magni- Fication Or to Add an Aperture Mask
    Beginning observing You’ll find six labeled maps to help you observe the Moon at www.Astronomy.com/toc. Two other methods to reduce the 10 tips for Moon watchers Moon’s brightness are to use high magni- fication or to add an aperture mask. Mountain ranges, vast volcanic plains, and more than 1,500 named craters make the High powers restrict the field of view, Moon a target you’ll return to again and again. by Michael E. Bakich thereby reducing light throughput. An aperture mask causes your telescope to act like a much smaller instrument, but The Moon offers something for every amateur astronomer. It’s The terminator will help you at the same focal length. visible somewhere in the sky most nights, its changing face During the two favorable periods described in #3, presents features one night not seen the previous night, and it point your telescope anywhere along the line that Turn on your best vision doesn’t take an expensive setup to enjoy it. To help you get the divides the Moon’s light and dark portions. Astrono- Some years ago, my late observ- most out of viewing the Moon, I’ve developed these 10 simple 4mers call this line the terminator. Before Full Moon, the termi- ing buddy Jeff Medkeff intro- tips. Follow them, and you’ll be on your way to a lifetime of sat- nator marks where sunrise is occurring. After Full Moon, duced me to a better way of isfying lunar observing. sunset happens along the terminator. 7observing the Moon: Turn on a white Here you can catch the tops of mountains protruding just light behind you when you observe high enough to catch the Sun’s light while surrounded by lower between Quarter and Full phases.
    [Show full text]
  • Three Naked Eye Galaxies? Dave Eagle
    Three Naked Eye Galaxies? Dave Eagle. Eagleseye Observatory. Star hopping to M31, The Great Andromeda Galaxy. In the autumn sky in the northern hemisphere, the constellations of Perseus and Andromeda are very proudly on display, located on the meridian around midnight, and visible from most of the world. The Great Square of Pegasus is a distinct asterism of four stars. Using just your naked eye, find this square of stars. Incidentally, the top left star (all instructions are now as seen from the northern hemisphere) Sirrah, is now actually Alpha Andromedae. From this square of stars take the top edge of the square and carry the line on towards the left (east) and up. Just under half the distance of the top of the square, you should come to another reasonably bright star. Slightly left and up again, taking a slightly longer journey, you will come to another star of similar brightness. This is Mirach or Beta Andromedae. When you have found this star, turn 90 degrees to the right. You will then see two fairly bright stars leading away. Aim for the second star and gaze at this star. If your skies are reasonably dark, just above and to the right of the second star you should be able to see a faint smudge. This marks the location of M31, The Andromeda Galaxy. In five hops we have found our quarry. Figure 1 – Star hopping from Sirrah to The Andromeda Galaxy. This is the most distant object you can see with the naked eye and is almost 2.5 million light years away.
    [Show full text]
  • Meeting Program
    A A S MEETING PROGRAM 211TH MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY WITH THE HIGH ENERGY ASTROPHYSICS DIVISION (HEAD) AND THE HISTORICAL ASTRONOMY DIVISION (HAD) 7-11 JANUARY 2008 AUSTIN, TX All scientific session will be held at the: Austin Convention Center COUNCIL .......................... 2 500 East Cesar Chavez St. Austin, TX 78701 EXHIBITS ........................... 4 FURTHER IN GRATITUDE INFORMATION ............... 6 AAS Paper Sorters SCHEDULE ....................... 7 Rachel Akeson, David Bartlett, Elizabeth Barton, SUNDAY ........................17 Joan Centrella, Jun Cui, Susana Deustua, Tapasi Ghosh, Jennifer Grier, Joe Hahn, Hugh Harris, MONDAY .......................21 Chryssa Kouveliotou, John Martin, Kevin Marvel, Kristen Menou, Brian Patten, Robert Quimby, Chris Springob, Joe Tenn, Dirk Terrell, Dave TUESDAY .......................25 Thompson, Liese van Zee, and Amy Winebarger WEDNESDAY ................77 We would like to thank the THURSDAY ................. 143 following sponsors: FRIDAY ......................... 203 Elsevier Northrop Grumman SATURDAY .................. 241 Lockheed Martin The TABASGO Foundation AUTHOR INDEX ........ 242 AAS COUNCIL J. Craig Wheeler Univ. of Texas President (6/2006-6/2008) John P. Huchra Harvard-Smithsonian, President-Elect CfA (6/2007-6/2008) Paul Vanden Bout NRAO Vice-President (6/2005-6/2008) Robert W. O’Connell Univ. of Virginia Vice-President (6/2006-6/2009) Lee W. Hartman Univ. of Michigan Vice-President (6/2007-6/2010) John Graham CIW Secretary (6/2004-6/2010) OFFICERS Hervey (Peter) STScI Treasurer Stockman (6/2005-6/2008) Timothy F. Slater Univ. of Arizona Education Officer (6/2006-6/2009) Mike A’Hearn Univ. of Maryland Pub. Board Chair (6/2005-6/2008) Kevin Marvel AAS Executive Officer (6/2006-Present) Gary J. Ferland Univ. of Kentucky (6/2007-6/2008) Suzanne Hawley Univ.
    [Show full text]
  • Space Viewer Template
    Space Viewer Template View Finder This goes on top of your two plates, and is glued to the paper towel tube. We recommend using cardboard for this. < Bottom Disc This gives your view finding disc structure, and is where you label the constellations. We recommend using card stock or lightweight cardboard for this. Constellation Plate > This disc is home to your constellations, and gets glued to the larger disc. We recommend using paper for this, so the holes are easier to punch. Use the punch guides on the next page to punch holes and add labels to your viewer. Orion Cancer Look for the middle star of Orions When you look at this constellation, look sword, that is an area of brighter nearby for 55 Cancri a star that has light, it’s actually a nebula! The five exoplanets orbiting it. One of those Orion Nebula is a gigantic cloud of plants (55 Cancri e) is a super hot dust and gas, where new stars are planet entirely covered in an ocean of being created. lava! Cygnus Andromeda This constellation is home to the This constellation is very close to the Kepler-186 system, including the Andromeda Galaxy (an enormous planet Kepler-186f. Seen by collection of gas, dust, and billions of NASA's Kepler Space Telescope, stars and solar systems). This spiral this is the first Earth-sized planet galaxy is so bright, you can spot it with discovered that is in"habitable the naked eye! zone" of its star. Ursa Minor Cassiopeia Ursa Minor has two stars known While gazing at Cassiopeia look for with exoplanets orbiting them - the“Pacman Nebula” (It’s official name both are gas giants, that are much is NGC 281).
    [Show full text]
  • Introductory Exercise – Naked Eye Night Sky Observations Introduction
    Introductory Exercise – Naked Eye Night Sky Observations Introduction One of the goals of any Astronomy class is for the students to become more familiar with objects in the sky from here on out. Knowing how orient yourself with respect to the cardinal directions and use sky maps or star wheels is a valuable valuable skill. You never know when it may come in handy and you will be able to clear up misconceptions among your relatives and friends. You will be able to calm their fears about imminent alien attacks from space or Earth's catastrophic destruction by an incoming asteroid or comet on collision course by being able to identify that light in the sky. It turns out that you can make awesome and meaningful observations of the sky just with your naked, unaided eyes. Neither telescope nor binoculars are necessary. The Crash Course Astronomy #2 "Naked Eye Observations"(https://www.youtube.com/watch?v=L- Wtlev6suc&t=23s) is a great primer on the variety of celestial objects you can observe just with eyes and how to go about it. Before you set out to make your own observations there are a few preparations you can make for the best experience: be aware of light pollution at your observing location, being able to estimate angular sizes and distances of objects in the sky, and having a sky map handy. Light Pollution Light pollution by manmade light sources is a big problem when observing the night sky. For example, here is an image by Jeremy Stanley showing part of the constellation of Orion seen with very little light pollution and with more severe light pollution.
    [Show full text]
  • Observing Sun with Naked
    Observing Sun with Naked Eye Structure of the Eye The Iris Light rays from objects at which the eyes are aimed come together at the fovea centralis, a tiny pit in the center of the macula. This is the area of sharpest vision. Light rays from objects to the sides strike other areas of the retina. The Retina The solar spectrum at Earth chiefly comprises of infra-red rays (say from 6500 nm - 723 nm), visible light (from 723 nm - 399 nm), and ultra-violet rays (from 397 nm - 100 nm). It would be interesting to note that the sunlight contains about 58% infra-red radiation, 40% visible and 2% ultraviolet. Optically Important Regions of the Electromagnetic Spectrum The Electromagnetic Spectrum Wavelength in nm How direct and scattered light is transmitted through the entire eye The radiation that traverses the cornea is absorbed in part by the ocular tissues while some 10% of the incident energy is dissipated by diffusion. Most radiation which falls upon the pigmentary layers of the iris and the retina, whether infra-red, visible or long ultra- violet, is absorbed and converted into heat. Of the long-wave radiation which traverses the transparent media, the aqueous humour absorbs all the infra-red above 2700 nm and partly at lower wavelengths. The lens absorbs all radiations longer than 2300 nm, but, below it, it shows two bands of selec•tive absorption near 1900 nm and 1500 nm. The permeability of the eye to the electromagnetic spectrum With a small source ( a point source or with small angular diameter) of energy, damage may be caused at the retina while the anterior structures are left unaffected.
    [Show full text]
  • Introducing the Bortle Dark-Sky Scale
    observer’s log Introducing the Bortle Dark-Sky Scale Excellent? Typical? Urban? Use this nine-step scale to rate the sky conditions at any observing site. By John E. Bortle ow dark is your sky? A Limiting Magnitude Isn’t Enough precise answer to this ques- Amateur astronomers usually judge their tion is useful for comparing skies by noting the magnitude of the observing sites and, more im- faintest star visible to the naked eye. Hportant, for determining whether a site is However, naked-eye limiting magnitude dark enough to let you push your eyes, is a poor criterion. It depends too much telescope, or camera to their theoretical on a person’s visual acuity (sharpness of limits. Likewise, you need accurate crite- eyesight), as well as on the time and ef- ria for judging sky conditions when doc- fort expended to see the faintest possible umenting unusual or borderline obser- stars. One person’s “5.5-magnitude sky” vations, such as an extremely long comet is another’s “6.3-magnitude sky.” More- tail, a faint aurora, or subtle features in over, deep-sky observers need to assess the galaxies. visibility of both stellar and nonstellar ob- On Internet bulletin boards and news- jects. A modest amount of light pollution groups I see many postings from begin- degrades diffuse objects such as comets, ners (and sometimes more experienced nebulae, and galaxies far more than stars. observers) wondering how to evaluate To help observers judge the true dark- the quality of their skies. Unfortunately, ness of a site, I have created a nine-level most of today’s stargazers have never scale.
    [Show full text]
  • 2016 Naked Eye Astronomy President's Message
    Bringing Astronomy to the Public Vol 33 No. 2 Summer 2016 President’s Message 2016 By John Parker FPOA Program Dates Summer is almost over and Fall is quickly com- ing. As of this writing, we have provided what we Saturday Evening Programs estimate to be over a thousand visitors with 13 Apr 2, 9, 30 May 7, 14, 28 presentations, most followed up with public viewing and 5 solar programs for visitors to the park. I say Jun 4, 11, 25 Jul 2, 9, 30 most because weather can be a factor and the So- Aug 6, 27 Sept 3, 10, 24 beranes fire near Big Sur impacted us as well. As Oct 1, 8, 29 you know, we currently rely on a few board mem- bers as well as a number of interns (students from Hartnell College) that work with the FPOA to pro- Solar Programs vide these presentations to the public. Some of our Apr 2, 30 May 28 Jun 25 regular members have also provided presentations Jul 30 Aug 27 Sept 24 Oct 29 in the past and we encourage you, as members, to come up and give a talk or help out with the public viewing programs when you are able to. The Board Meetings FPOA is able to do what it does, bringing astrono- my to the public, because of the efforts of our vol- Jan 9 Feb 6 Mar 12 Apr 9 unteers. May 7 Jun 4 Jul 9 Aug 6 To celebrate our membership and take care of Sept 3 Oct 1 Nov 5 regular FPOA business, we are having our upcom- ing Annual Members Meeting and Barbeque to be Special Events held on Saturday, September 24.
    [Show full text]
  • Naked-Eye Astronomy: Optics of the Starry Night Skies
    Naked-eye Astronomy: Optics of the starry night skies Salva Bará Universidade de Santiago de Compostela, Optics Area, Applied Physics Dept, Faculty of Optics and Optometry, 15782 Santiago de Compostela, Galicia (Spain, European Union) [email protected] ABSTRACT The world at night offers a wealth of stimuli and opportunities as a resource for Optics education, at all age levels and from any (formal, non formal or informal) perspective. The starry sky and the urban nightscape provide a unique combination of pointlike sources with extremely different emission spectra and brightness levels on a generally darker, locally homogeneous background. This fact, combined with the particular characteristics of the human visual system under mesopic and scotopic conditions, provides a perfect setting for experiencing first-hand different optical phenomena of increasing levels of complexity: from the eye's point spread function to the luminance contrast threshold for source detection, from basic diffraction patterns to the intricate irradiance fluctuations due to atmospheric turbulence. Looking at the nightscape is also a perfect occasion to raise awareness on the increasing levels of light pollution associated to the misuse of public and private artificial light at night, to promote a sustainable use of lighting, and to take part in worldwide citizen science campaigns. Last but not least, night sky observing activities can be planned and developed following a very flexible schedule, allowing individual students to carry them out from home and sharing the results in the classroom as well as organizing social events and night star parties with the active engagement of families and groups of the local community.
    [Show full text]