Document 6447384
Transcription
Document 6447384
THE SMITHSONIAN INSTITUTION WARNING: FACT SHEET The Smithsonian Institution is a nlu~,¢um, education and research complex of 17 nluscu111~ and galleries, and Ih¢ National Zoological Park. Fifteen musetnms and galleries are located in Washington,I).(’., two are in NewYork City, and lhc Nadonal Zoo is in Washington. "l~n of the museumsand galleries are situated on ~he Nadonal Mall between Ihe tLS. (’apiml and Washington MonumenL One of the world’s leading scientific research centers, the Institution has facilities in eight slates and the Republic of Panama. Research projects in the arts, history, and science are carried out by the Smithsonian all over the world. The new National Mt~scum of the American Indian is scheduled to open on the National Mall in 2002. The centerpiece of the museumis the priceless collection of Native American artifacts ~ransl~rred to the Smithsonian from the Museum of the American Indian, Hcyc Foundation (New York). The New York exhibilion facility - the Hcye Center of II~c National Museumof the American Indian opened Oclober 30, 1994 in lower Manhaltan. Anolher new museum, the Nadonal PosIal Museum, is Iocalcd near Union Station on Capitol Hill. Devoted to the history of the U.S. mail service, the museum houses the world’s largest and most comprehensive collection of its kind, with more than 16 million stamps, covers, and artifacls. Onlyfor useby children over8 yearsold. Onlyfor use under the supervision of an adult. DONOT VIEW SUN THROUGHIELESCOPEAS SERIOUSINJURY MAYRESULT! CAUTION: Readthe instructions before use, follow themand keepthemfor reference.Storetelescope set out of reachof smallchildren. ITEM#1144 AGES8 & up SMITHSONIAN 50x Telescope HISTORY James Smithson (1765-1829). a British scientist, drew up his will in 1826 naming his nephew. Henry James Hungerford. as beneficiary. Smithson stipulated that should the nephew die without heirs (as he did in 1835). the estate would go It, the United States tt, ft,und "’at Washington, under the name of the Smithsonian Institution. an establishment for the increase and diffusion of knowledge..." On July !, 1836, Congress accepted the legacy bequeathed to the nation by James Smithson, and pledged the faith of the United States to the charitable trust. In 1838. following approval of the bequest by the British courts, the United ql~l~.~: r~.~’PivPH’~,,~_ithson’s estate - bags of gold sovereign,~ of $515,169. Eight years later, on August I O, 1846. an Act of Congress signed by President James K. Polk, established the Smithsonian Institution in its present form and provided Ibr the administration of the trust, independent of the government itself, by a Board of Regents and Secretary of the Smithsonian. DEAR CUSTOMER, NSI is the manufacturer of this kit. If we madean error and left something out of this set, or if something is damaged,we are sorry and wish to correct our error. Please do not return the set to the store where you purchased it, or to the Smithsonian, as they do not have replacement parts. Instead, write us a letter giving us: 1. Dateof Purchase Purchased 2. Where 3. ModelNumber 4. Name of Set 5. BriefDescription of Problem 6. Sales Slip Wewill do our best to satisfy you. Quality Control Department, Natural Science Industries, Ltd. 910 Orlando Avenue, West Hempstead, NY 11552-3942 (516) 678-1700 PRINTED IN CHINA ITEM NO. 1144 ~2000SmithsonianInstitution - Natural ScienceIndustries, Ltd. 910 ORLANDO AVENUE¯ WESTHEMPSTEAD, NY 11552-3942 ¯ (516) 678-1700 Parts t)t" YourTelescope ()bjectivc I.ens Lid 2 Objective Lells 3 i~ens Hood 4 ’rclcscopc Tube 5 Bracket Knob Boh 7 Tripod Legs 8 Focusin~ Tube Holder 9 t:ocusin,~ Tube 10 Eyepiece II Eyepiece lad I. ~ I:ocusi]~g Knob 13 l)iagonal Mirror 4 Care of Your Telescope Your telescope should hc kcpl away from dusl and moislllrc. I IJlC Ic~lSCS~cl dirty, blow any dust parliclcs olT before cleaning. Clean the lense~ with a moistened lens tissue. Alwaysstore your telescope in the box whennot in use. How MuchPower: Choosing the Eye I,ens Powerrefers Io Ihc ability of a telescope Io enlarge an image, or. in cflccl, bring il clo~cr to the viewer. Amountof magnifyingpoweris signified by a numberfollowed by an X (read "power"). So if you view an old, col at 50X. you arc seeing it as if you are 50 times closer to thai o~jccl. Poweris calculated by dividing lllc focal length of your tclcscope’s otLjcctive lens (probably indicated on the Ibcus tube) by lhc Ik~cal Icnglh ot" the cyc lens you select. The focal length of the eye lens is usually indicated on the eyepieceitself. 500mm (focal length of objective lens) Wayis much brighler. ’lb set, Ihe Milk~ Wayyou need to go where the sky is vcr~ dark when there is no moonin the sk3. There are patterns of hright sial% to he found here too. First lind the "Big Dipper", the hrighlesl stars of the constellation Ursa Major. The two stars at the front of Ihe houri of Ihe dipper poinl 1o Polaris, the Norlh Stal: Then I~flloxv Ihe arc of the handle to Arclurus, and then spike to Spica. High overhead look I~n" the large summerIriangle: Vega, Deneb, and Altair. Antares is a reddish-looking slat in the soulh, parl of lhe conspicuous constellation Scorpius. Be sure Io sxveep lhe summerMilky Waywilh hinoculars to lind dozens of rich star cluslers and fuzz3 palches of nebulosily (glo~ving gas cloudsL Note, Ihe ecliplic, the path of Ihe sun. moon and phmels is low in the nighltime sky and high in the daylime sky in the summer monlhs. FALL = 50X (power) Example: lOmm (focal length of eyepiece) ’l"hc Ior~gcr the fl~cal length of the eyepiece, the less the magnifyingpowerof the Iclescope: the shorter the focal length, the greater the power. So whenyou sclccl eye lens to inscrl into the diagonal prism, you’re really choosing what magnit3,ing poweryou wish to use for obserwttion. Helpful tlints for Setting Up YourTelescope 1 ) Unpackthe tripod fl’om the box. Next, s~and the tripod up verlically by pulling Ihe leg extension anct sprcadirlg Ihe legs apart fully. 2) Slide the telescope bracket (5) arKl adjusl Ihc holes. 3) Removethe lens lids ( I 1 &1 ) from the eyepiece and the objective lens (10 & 2). WARNING: DO NOT VIEW SUN THROUGH TF.I,ESCOPE AS SERIOUS INJURY TO EYE MAY RESUI/F 17 Observing Astronomical Objects Through Your Telescope l) Glance through the main telescope% cycpiccc{ I{)) For your o~cct. (Note: mayhave to alter the angle ol" the telescope slightly.) The o~ject will n~ost likely seem to beblLIrry at this ~tage,hul lhal i~ Ilorlllal. Youare just trying to get the o~ject in the viewing field of your telescope lens. ()nee you have accomplished this lask, fitsten the knobboll (6) Io keep Ihe accuracy of your lelescope steady. 2) Nowat{iust Ihe focusing tube (9) by turning the focusing knob (12) slowly back and fl~rlh unlil Ihe blurred o~jecl becomesprecise. 3) If you are going to be looking through the telescope Ik)r a short period of time, you can insert tile eyepiece (10) directly into the focusing lube (9). To be comfortable whenusing your telescope for longer periods of lime, place the diagonal mirror (13) inlo the Ibcusing tube (9) and Ihe eyepiece (10) inlo the nal mirror. WINTER SOUTH The~.linter ~,k.,, 1 b, dominak’d hy tl]~ bright constellation()rion. the hLml~r,with hi~ prominent h~ll ~ ) three equally N~aced~tar~. Notethe I’ill~ of blli~ht Marx~lilrolitldhl~ ()l’iOl]: Ri~el, Aldeharan, (’apella. (’a~tor and Pollux. Pl’ocyon. and Sh’ill~ (the brightest M[Lr in the n]i~i]tthne ~ky). Betel~eu~e in the middle.l’i]i~ I~,q~ i~ ~Otllethl]e~ called the "’Winter Ilex~L~On."Onceyoucanidenfify the~e ~taF~ you ~’all work yOllf ~~ OLit to Lhe ~Llrl’Olllll]hl~ con~tellathm~. Note. the cc’lq~tk’, path of tile sun, inoon,andpmanet~ i~ highin the nightlhne~ky andIo~ ~11the d~l)’thlle ~ky the in the ~’il]- Overview nf the Snlar System By definition, our Solar Systemconsists of the Still, nine planets, their moons, and an ut~k~ownnumber of asteroids (small rocky bodies) and comets (small bodies of dust and ice). The inner planets, Mercury, Venus, Earth, and Mars, are similar in that they were lbnncd from dense, rocky materials, unlike the outer gaseous planets, Jupiter, Saturn, Uranus, and Neptune.Pluto is the oddity, a small rocky-like planet on the outskirts of the Solar System. Most asteroids are located in orbit (the path of one body circling another) between Mars and Jupiter. Beyomlthe orbit of Pluto, comets can be Ibund in the Oort cloud (a band of comets). Occasionally, the pull of the Sun’s gravity (lk~rce of attraction between two bodies) brings comets tracing exaggerated elongated orbits into the inner Solar System. Icl" / !. Our Solar System In Depth A. Mercury: Taking a Clnser Lnnk AlthoughMercuryis the fourth-brightest phmct, finding it in the sky can be difficult even whenyou knowwhere to look. Bccauxcit is the closest planet to the Sun, fromour viewing platform it is always in the same part of the sky as the Sun, visible only right after sunset or right bel’ore sunrise. This meansit is close to the horizon and our view is shrouded by the thickest part of the atmosphere (the gaseous envelope surlout~dit~g the [~arth). Circular depressions called impact craters, caused by debris hitting the surfi~ce, cover the entire surfitce of Mercury making it difficuh to distinguish it from the Moon.The Mercuryimpact craters do not appear as deep as the Moon’s, and the ring of ejected material around each crater is closer in. Mercury’s surface gravity is over twice that of the Moon, resulting in shallower craters, and preventing debris from travelling far from the impactsite. . - ¯ ’.-.-.-... ’" ~I ...... ’,..... ¯ " ,’-: The Milky Way:Wheuyou see the Milky Wayin the night sky. you maywell see howit got its uame.Throughoutthe ages, this band of lighl has also been referredas a river. Wenowknowthat this bandof light is made of stars leo far awayfor our eyes to distiuguish Clio point of light fronl another. TheMilkyWay is a spiral galaxyof about 300billion stars, resemblinpa flat disk wilh a slight bulgein the center. ()ur Solar Systemis in a spur of’oneof the spiral armslocaled about 2/3rd of the wayout from the center of the galaxy. The band of light seen across our sky is our viewof the plane of the galaxy. In other words,if our galaxy were a pizza, fgomour slice of peppcroni, wewouldbe looking at the crust. Therifts of dark patchesthai wesee iu the Milkywayare uol holes opening up to the other side, but dusl and debris blockingour view. Thebright stars seen in these dark patchesare closer in to us than those in the arms. .’ ¯ " : ’: " -, ,- " :-: :--:- ~--. ~...~~’..5.... / .... ;.,, .... .... B. VENtJS: "l{ikiug a Closer l~ook Will] a nlaxiintlln nlagnitudc iiil~o~ The Andromeda Galaxy: Located in the constellation Andromeda, between Cassiopeia and Pegasus, is the clongalcd smudge of the Andromeda Galaxy. Even with a nice backyard telescope, you will see only ,’~ smudge. Just imagine that the light left that galaxy almost 3 million years ago and is ouly nowreaching our eyes. For those of tlS in the Norlherl] Henlispherc. with I]orma[ eyesight, the AndromedaGalaxy is the furthl3sl objc¢l visible wilk Ihe unaided cye, ]lid the only visible objectthal is lie] parl of our OWll Milky WayGalaxy, (apparolli brighti]ess)of-4.7.VciltlS brighlor lhan Iho noxl hrighl~l planol. Jupilor. Thougll known a~ lhc ~VOlliilg afler suns~l. WhenVclitl~ i~ clo~c to the horizon, it can appearto datlco and ~hilllnl~r thi’ough lho almo~phcricha/o. and i~ oflon nli~lakon for a UFOhovel’in 7 clo~c to the horizon. PlanetaryNebula:Believedto be qjectcd gas from dyingred giant stars, planetary nebulas generally appear as rings or hourglass shapes, looking mtich like planetary disks under low n]agnification. Examplesinclude the Ring Nebulain Lyra and the Helix Nebulain Aquarius. Supernova remnant: Ancxpaliding shell of gas reruainiilg after a violent explosion during the final stages of a star’s evolution. Example.~include Ihc Crab Nebulain Taurus, and the Veil Nebulain Cygnus. Galaxies:Defined as a concentrated assemblyof gas, dust and stars. Galaxies comein various shapes: spiral, irregular, and elliptical. Examplesinclude the WhirlpoolGalaxyin CanesVenatici andthe Pinwheelin Triangulum. ¯ " . ." ¯ I ’ :.~ .... ’: ~ ...... ...-7-, , " .... Star Clusters: Group of stars located closely together, helieved to share a comIllOi] origin, Star clusters can have thousands of stars or only a l~w, Examples include the Pleiades in Taurus and the Beehive in Call¢er. ...-__, .... i,. ., .~.~~~~-~ i---~,. . ;.,.. -.. I ..,~.~:. --,-- -_--~--.~Z"-, - .... .~ .’~ ~’~...... L, I. .... ¯¯ / - , . ! ...... i" .-"- "t,. \.’.: ’.., ~L.A ’.:’-.,:....... ~ -.-~., ’ ,. ¯ .. i ."..:.7..~.~l ’~i.; :"4¯ - hi .’~ ..’-t t ...... .// .... ~ ": . ,, ’" ".."" ’. ¯ . ,--:--~ ~ , ." ~ Globularclusters: Largergroupof hundredsof thousaudsof stars clustcrctl together andbelieved to share a common origin. Examplesinclude the Great GlobularClusterin Herculcsandthe M4in Scorpius. , , ~ ...... ¯ ~ " ¯ ~fl", ,.--’., ..... .. ~ Apparcnl lialh ill" Vi’nlls ill relationto the background stairsat one-day intervals.Themotion is shnihir to thaiof Mercury eXeClll Vl~llllSnllll’~snlorl~slowly ]lid lher~2trlil~rildl~ loops arl~flitflier aparl, MultipleStars: Two,three or morestars circling aroundthe samecenter of gravity. Moststars that appearto the nakedeye as a single pointof light are actually multiple stars, andmayrcquirc a telescope to see the nunaerouscompanions. Sirius in CantsMajoris a double, Rcgulusin Leois a triple, andCapcllain Aurigais a sextuple. Polaris is currently our NorthStar because il is len)porari]y locatedalmos[dir¢clly aboveI~arlh’s Norlh Pole. ()nee you hwalc Polaris, you hawfound norlh, m~~ouone of your cardinal diF¢clions. WhileIookin~ al Polaris. cast will bc your riBhl, w~ston your I~l’t, andsouth~il] bc behind~ou."l’hcsc diicctiolln b¢ imporlanl for findin B your wa~through the niBht sky, maKh) B the Bi~ I)ippcr lit1 hlvaJtiahIc+otlidcpost. Before IIl()V~ll~. t)ll, lakest)me1~111~1() illlprcsn ~()tlr falllil~andfriends. C’on~iclcr (l~c~an~ular) height ofP(~larh ahoxcthehorizon. Remember lhalPolaris ix totaled ahnosl dircclIX ab(wclhcN()rlh Pole. So, wcrcal lhcNorlhPole,Polaris wouldbc dirccll over xour head. Chances arc, X liftsin nollhccasewhereXouarcnow.So,wherearcXou?Polaris andxour canhelpXouIi~urc nomcof XourIocalion. A I’islheldal armsIcn~lh mcaxu~cx aboultO dc~rccxfrompinkX knuckleto thumbknuckle.If Xou wcrc in Washin~lon. I).(’., ilwouldlakefourI’isls, oneslacked onlopofIh¢olhcr, reachPolaris. It.jusl xohappens lhalWashm~lon, I).(’. isncarl norlh X ~0 dc~rccs lalilud¢, mcanin~ 4()dc~rccs norlhofEarlh’s cqualor. IfX()uwcrcIurlhcr perhaps Fhwida, ilwouldlakeonlX lhrccfisls, ~ivcor lakea I’in~cr. BX mcasurin~lh¢hciBhl of Polaris inthiswax,Xoucanrou~hl xournorlh I~IiX dclcrnfinc ludc.If XouwcrcbelowlhcEarlh’s ¢qualor, Xouwouldnolfinda Soulh Slar.so dclcrminin~ xoursoulhlaliludc wouldh¢ muchlou~h¢~. When you searchthe northern part of the sky, the only changesyou will find are Ihc positions of the constellations as they appearto movearoundPolaris. If you canimagineIhJn part of lhc sky an an umbrella,Polaris wouldmarkthe lip at the lop. As youlwirl lhc umbrella,lhc slats closer Io Polarin movearoundin a li~hlcr circle. The further awaythe star is from Polaris, the larger the circle, until eventually the slar falls hch)wthe horizon, appearingto rise in the Easl andset in Ihc wcsl. The Marsthal fall belowlhc horizonare consideredseasonalconstellations. "[’hey are only visible at ccrlain times of lhc year, andIhc particular seasondclcrmincshow E TAKIN(; A CI,OSERI,OOK: You can find many sky objects with the unaided eye. Before you look. remember to allow your eyes time to adapt to whatever darkness is available. Evenif you arc in an area affected wilh light polItllion, somestarry o~jects will he visible after you stand in the dark Ibrabout I0 IllilltlleS. The further awayfrom the lighls, the morelime your eyes need to fully adapl~around 20 minutes in a nice dark sky environment. Cerlainly if the Moon is up, look while you are waiting. The brightest slars and planets will become visible first; these are excellent guideposts in their ownrights. Eventually, the dimmer stars will come inlo view. The darker the environment, the more stars you will see. If you arc in a nice dark sky, you will be treated to the Milky Way and some nice deep sky objects as well. A good star map will show you where to find deep sky o~jects, manyof them visible wfih the unaided eye as nebulous palches. Througha telescope, Venusappears as a featureless white ball that goes through phases similar to the Moon’s. As you lbllow these changing phases, you maysee a dark atmospheric ring oudining the plancl. Notice also thai the slim banana shapedcrescent appears muchlarger than its fuller than half bul not quite full gibbous phase, suggestingthat duringits crescent phase, it is closer to us, while its gibbous phase occurs whenit is far away, on the olhcr side of the Stun. C. MARS:Taking a Closer Marsis our first outer phmet.It is reddish brownin color. When the Earthcomes betweenMarsand the Sun, Marsis at opposition (opposite the Stm in the sky). At these limes, Marsis very close to the Earth and appears bright. WhenEarth andMarsare far apart in their orbits, Marslooks muchfainter. Since the orbit of Marsis elliptical (owd) someoppositions are closer than others. In one month, Marsmoves against the backgroundof stars on the average aboul I-I/2 hamls dircction again to continue along its easterly journey. This is called retrograde mntion. If you could see the Solar System from above, you would scc Earth movingfaster on the inner loop, passing slower Marson the outer loop. Mars appearsas a disk througha telescope -no longer just a pinpoint of light, as it looks to the unaidedcyc. Somesurlktcc detail becomesvisible, such as the darkcr regions and the white polar caps. Unfnrttmatcly.as Marsnears the sun, solar radiation triggers massivedust stormson the planet, so thoughthis is the ideal time to look at Marsbecauseof its close dislance to Earlhand the Sun, it is the worst time tk)r detecting any surface dclails. Ducto the presence of iron oxide, the rocky surface of Marsis the color of red clay. There is no atmosphereon Mars:the surface gravity was not strong enoughto hold onto the gasscs during the cooling period. Nor is there any surface water, and what water there maybe on Marsis frozen beneaththe north and south axis or poles, covered by dry ice. D. STARS:By defivfition, a star has its own nuclear power source, and is capable of producing its own light. Stars come in many different colors. Yon will notice blue, orange, red, and yellow stars. Our own star, the Sun, is a middleaged average yellow star, called a main sequence star. Average stars begin their life in a cool cloud of gas and dust. As the star consumes its own matter, it Apl)arentPathof Marsin relalion to the hack~roan(I stars at one-day interw|ls. Themotinn right to left (west to east) on the average, with relrogra(It, <easl to west) motionxvhenthe inner plane! (Earth) comeshetweenthe outer phlnel (Mars) the Sun.Note,Ihis means that d aring relrograde Marsis at "npposilion," opposite the Sunin the sky: nverhead,’it midnight. D. JUPITER: Taking a Closer Look Jupiter is generally hrighlcr than the brighlest fixed star, but not as bright as Venus. Jupiter is visible fi’om somewhereon Earth fi~r I I out of 12 months of the year. It moves slowly across the sky, and once I~)ulld is easy to track. becomes part of the main sequence, until gradually becoming a red giant or supergiant, then finally ending ils life by shrinking to a white dwarf. A very massive star at birth quickly reaches its hot stage, becoming a white or blue-white star, collapses to a white dwarf, and perhaps further collapses into a neutron star. or even further inlo what is called a black hole. Whenyou look into the night sky, the blue white stars are the youngcsl, hottest, and brightcsl. The red slars are cooler, older, and generally dim. Main sequence stars range fiom cool red to hot blue-white. Though not the norm, you can still find bright red stars, and dim white stars. Also, many supergiants, because of their location in ~he universe, look like ordinary stars from our viewpoint. E. FINI)ING DIRECTION: Learning yt)ur way around the sky can be easy you get to know a few simple guideposts. I+ealn the brightest stars in groups (such as the Winter Itcxagon, the SummerTriangle. etc.) and a few t)l" the most prominent constellations (()rion, the Big Dipper. Scorpius, etc.). You don’t to know the whole sky to find your way, as long as you know a few roll-able patterns that can be found easily. ()no of the most famous guideposts, for Northern Hemisphere observers is the Big Dipper. Using the pointer stars of the Big Dipper, draw an imaginary line through the sky until you reach the first bright star, Polaris, our North Star. THIS DISTANCE EQUALS YOUR LATITUDE Apparent path nf Jupiterin relation tn the background stars at five-day intervals. Themoti(ms of all of the oaler planets are similar tn the mntionnf Mars,excepllhe speedsare progressively sh)werand the retrogradeInops are progressivelycloser Iogether. With ordinary binoculars, Jupiter appears as a yellow oval disc with its four brightest (Galilean) Moonsclose by. Just how many of the Moons are visible will depend on each of their locations in their orbil around Jupiter. 4 --YOUR ¯ HORIZON NORTH From: "Stars andPlanets", byW.S.Kals.~1990 byW.S.Kals.Reprinted withpermission of SierraClub Books 13 Earth’sOrbit : Earths O, rb~t ... ~ o~ec.tion o~Sun"~’~-~ . Sun Total Annular Partial They mayhe all on one side, spread out equally, in transit (passing in front of Jupiter), or hiding behind the planet. A small telescope will reveal some of Jupiter’s cloud bells. Large Iclcscopcs reveal cloud slr’ucturcs of light zones and dark bclt~ ctossitlg Jupiter’s cqualor, as well as irregular ~pots alld streaks. From north Io south, Jupiter changes in appearance. The North Polar Regionis the least dclailcd. The Norlh "l~mpcratc Bell is bordered I~y red colored whirlpools. The Norlh Tropical Zone coulains the lighter level of clouds and appears bright white. The North I~tlUatorial Belt diH~lays hurricane wind #uxts of over 355 milc~ per hot. movingin difl’crcul directions. E. Saturn: Taking a CI.ser (;chorally, Salulll looks like a bright first magnitudestar of no particular color, is never as brilliant as Venusor Jupilcr, and its brightness will cllangc depending on how muchvisible sunlighl is rcflcclcd off ils rin~s. ," ’ track of Saturn ~ Kccptng is easy: it i’cmains in the same area of the sky for months, movingabout a hand in oucyear. It is the l’arthcnt planet l’r(m] the sun thai wc caneasily scc with the unaided cyc. .... ~:... ¯ .b,:.. (Left) Courtesyof. "Facts on Fde". 3rd Ed~hon.Market HouseBooksLid , Aylesbury. Untied Kingdom (R~ght) Courtesy el "Skywatch Eyes-OnAchwhesfor Gelling Io Knowthe Stars"¯ Peter Lancaster-Brown.Adetburgh, Suffolk, England 11. Overviewnf the evening sky. A. OUR VIEWINGPI.ATFORM: Whcu looking oul into the night sky, rememberthat it iN only tron~ our special viewing platlorm that the sky looks as it does. Earthis a small planet, circling a very ordinary star, in.just oneof many galaxies groupedlogclher in a universefilled with galaxyclusters and dark mattee. Keepin mindthai the viewis dil’fcrcnl from everyspot in the universe. B. CONSTEI,i,ATION:A constellation by definition is a portion of the sky separated from other areas by agreed upon boundaries. Every culture that we knowof looked up al the sky and namedareas after things that were either familiar’" TM ..... ; .... , ..... or,,, ~ ....... ’ .... partof their .... ~,,r,- M,,,’~cultures named star patterns, the forerunners of our modern constellations. The Arabs mostly namediudividual stars rather than groups of stars. SomeSouth Americancultures cvcn named the dark patches in the Milky Way. As you can imagine, there were manynames for specific areas in our sky. In 1930, an association called the International Astronomical Union, an organization responsible for establishing international standards and namingastronomical objects, divided the sky into 88 specific boundaries, and assigned them official names. Westill use these names today. Every part of the sky falls within one of these 88 boundaries. Think of these divisions as slate lines on a mapof the United States. C. ASTERISM: An asterism is any generally accepted group of stars not off’icially namedas one of the 88. Twoexamplesare "’The Big Dipper," which is part of the constellation Ursa Major, and "’The SummerTriangle," borrowing stars frorn three official constellations, Cygnus,Lyra, and Aquilla. . .. ¯ .’ .." ,’ :~...: ./.. . . .... ~’~.-~. .,,.....:..,. ¯ ...,. ,-. .... ~.:.- .&..! ..,.. ..,:, ":..--~. .,. ~ . - .,. , ,., <’ ~ -~ ._ ..... , ’ ~. ¯ . ,".... I’: ,- ’ , ¯ ¯ , --:;~ .. ~ ,,..., : z Apparenlpalh of ~alurn in relatioa to the hat, kgroundstars al five-day i~tervals. Note, SalurB movesabout half as I~r betweenrelrograde loops as Jupiter. The retrograde loops are a little over one year aparl. Saltlrn’s rings arc nol really wilhin rangeof slandardbinoculars. However,when viewedthrough a small telescope, they becomevisible as humpson either side with visible gapsseparating the rings. Depending on whereSaturn is in its 29 year orbit, the rings can bc seenanywhere from edgeon [o fully open.Twiceduring Saturn’s orbit, the rings will bc edgeon and disappearfrom our view completely. Close up viewsof Saturn’s rings showhundredsof ringlets, somebraid~d, wflh small shepherdingmoonsdividing the rings sections, which are made mostly of ice crystals ranging in size from a t~w centimeters to a t~w meters. Like Jupiter, Salurn is squashed at the poles, has bandedrings, and large white hurricane storms. ~a|LIrBas ~eeli Illi’otl~li arrialettr I~leseope Whena lunar eclipse occurs, llOl everyone on Earlh wilt be able to see it. The ffloon must be above your horizon. So if the moonis full at 4:02 p.m. ES"I2 and this just happens to he a lime whenthe nloon is belowyotir horizon, yotl will ilOt see the eclipse. However,SOl~ooneon earth will, and with clear wealhor, yotl will still be trealed Io a filll moonthat evening--;jttsl noi an eclipsed one. A lunar eclipse is entirely safe to watch with the unaided eye, hinocuhirs, or a telescope. E Uranus: Taking a Chiser I,ook Uranus is visible to the unaided eve only under exceptionally clear conditions. and even then it never gels brighter than a faint 6th magnitude star. However, once you find [Jranus, her very slow movcmenlIhrough the slar field should keep you on lrack lbr manyyears. Apparent path of Uranus in relation to the hackground stars lit ten-day intervals. Note, Uranus movesso slowly that its retrograde loops overlap. Also its orhit is closely aligned with the earth’s orbit, so the loops don’t sl~llld Olll well in a diagramlike this. Onceyoufind Urantlsin tile night sky, a smalltelescope will tl’ailsfol-rll ils Sl~ll’like inlage into a small greentTatut’oless disk. WatchI]lr severaleveningsto see UralltlS nlovethrouThlhc hack~l’ound stal’~. []veil lhrotlgh the lar+0st lele+copos and probes, a green l~’attlroloss disk is all we sco. Hnwevcr,these largo telescopes arc necessary to spol i~er 15 salclliles, all smaller than Earth’s Moon. G. Neptune: Taking a Closer I,ook Neptuneis till 8th niagriilude binocular object, arid looks Iikc a bltie star. With patience, over manynighls, you can see Ihe plancl moveagainst the background stars. Youwill need a good-sized telescope Io view Neptuneas a disk or Io see its largest moon,Triton. 6 Solar Eclipse A solar eclipse occurs only whenthe Moonis directly bclweenthe Earth tllld Still. Because the sun is 400 iimes larger than the moonand the moonis 400 times closer to the earth, the sun and moonappear to be the same size. Tiffs allows the nloon at times Io completely cover the sun during an eclipse. As the shadow sweepsacross the earth, allyOile located in its palh will see the nRiOll Ct)VCl’ [he ~tlll, tilid lt~r tip Io seV~ll milltliCS, blockits light. If you alo Oll Itlo OtllOr limiis of tke mOOll’~~htlOOW,yOtl will wilnossa parlial eclipse, rind ~o~only partial coverage of the Still. Nol all solar eclipses are equal. The Moon’sorbit around the Earth is oval, or elliptical. The distance the moonis from the earth will affect its apparent diameter. The closer the moonis to the Earth, the larger the moon’sapparent diameter; the farther away, the smaller. Solar eclipses that occur whenthe moonis closer to the earth will be longer, up to about seven minutes. If the Moonis farther fiom the Earth the duration of the eclipse will be shorter, or if it is sufficiently far fi’om the Earth it will t~il to completelycover the sun. An "annular eclipse" occurs when a ring (or annulus) of bright sunlight remains surrounding the disk of the Moon.If the Moonis not centered on the disk of the Sun the eclipse will be partial. Even a total eclipse starts and ends with a partial phase as the Moonslowly covers and uncovers the sun. Wheneverany part of the bright white disk of the sun is visible it Call damage your eyes. Do not look at a partial or annulareclipse, or the partial phases of a total eclipse, withont specially designed eye protection. The brightest slars and planets becomevisible during a solar eclipse, and anirnals think it is lime lbr bed, nlis/aking the darkness lbr llight. WhenIhe nlooll nearly covers ihe stln, righl belbre or after totality, bright beads of lighl, knowll as Bailey’s beads and thc diamondring effect, are visible. These are places whcre the Sun shines through the Moon’s craters and willeys. During a total solar eclipsc, wc can sce the Sun’s dazzling corona or outer layer. Total solar eclipses can occur up to 5 times a year, but seem rare because 300 years can pass before one is seen in the same location again. 11 As the MoonCol]thltles travelling cotlllter¢lockwise arotll]d the F.arth, it soon becomes visible directly al’tcr StlllSet ~.IS a Ihin crescent, with its points hacktowards Ihc easl. This phaseis called a w,.~i,g cresce,t. As Ihe Illollth plogresses,lhe Moonmovesfl.lllher caslwardill Ibe lwjli~hl sky, growjng f;.|ller (or Waxing) inlo a./)’r.sl qllarler Moo11, ;.I phase we,,cu as a half ]jl M~.)oll,Ihe weslern half. As lhe Moonmovesfurther easl Ihrough the starry sky, growing Ii~ller its u’,xi,g gibbous phase. still, look for Oncethe Moonis./)dl, it will rise as the sun sets. The Earth is betweeuthe Moonand StIll now. but the Moonhas only BoneIhloU~]l half of Jim phases. ~bout 14 days into its cycle. Still tlavclhng eastward Ihrough the starry sky, visible only after the Still has set, wc begin to scc less of the stmlit surface of tbc Moon,a phase called the Eventually, only half the Moonis lit again, but this time the other half or the eastern half is lit, a phase called htst or third q,arter. ((~ucss wherethe sun is!) At this time, it is well after midnight. Waningthinner every night, we will eventually find the motto as a thin crescent, only this time the points arc airncd west awayfrom Ihc sun rising.ju.st behind it in the cast. This phase is called Apparent path of Neptune in relatiun to the Ir.|ckgruund stars al ten-day intervals. I,ike Uranus,Neptune’sretrogradeluops overlap. Aside from Earth, Neptune is the bluest plzmct in the Solar System. Visible are the Great and Small I)ark Spots in Neptune’s southern region, and an atmosphere speckled with white clouds of methane ice. H. Pluto: Taking a Closer I,ook Telescopic views show an elongated image, indicating two bodies, rather than OllC. Eventually the moonwill bc m,wagain, lost in the sun’s ~larc, completing its monthly cycle. It is only during its ilew illOOli phase that the mooncannot be seen in the sky, day or night, anywhere on earth. l,unar Eclipse An eclin,~e hi’the M~mI~lkes phlce when Ihc F, arth is lined up direcllv in between the Sun and Moon. Whcu lined up perfectly, the Earlh blocks the sun from shining on the moon. ()r another way Io think of it in that the moon passes through the shadow Earth cants into space. For up to I hour and 47 minutes, you can see this shadow slowly creeping across the face of the moon. This Earth shadow on the moonis circular, providing early proof Ihal Ihe Earlh is round. An eclipse of the Moon can only take place when the moon is full. However, because the orbit of the Earth-Moon system around the Sun is tilled, a lunar eclipse does not occur each time there is a full Moon. Generally, the fnll moon passes just above or below the shadow of the Earth. This allows for various types of hmar eclipses: total (as described above), partial (Earth’s shadow covers only a porlion of moon), or penumbral (just skimming tbc edge, no visible bite, but some darkening of the moon). For total and partial eclipses, Ihc iiioon’s shadowy area is usually illuminated by refracted sunlight from earth’s atmosphere. 10 Apparentpath of Pluto in rclatiun lu the backgrnund stars at ten-day intervals, lake Uranus andNeptune,Plutu’s rctrugradeInopsuvcrlap, but unlike the rest of the planets, the orbit nf Pluto is highly inclined to the earth’s urhit. Imaginesomeonewalkingslowly past ynuhalf way acruss the rnom while you muve your head hark aud h;rth ab{mt once every sccnnd. The motiunuf your headrepresentsthe mntionof the earth as we Innkat Pinto drift slowly past in the distance. Theright-to-left drift is causedby the nmtionof the planet. Theluopingis caused by the motionof the earth. 7 I. MOON: Taking a Closer I.ook The manon tile moon, the rabbit on the moon, what do you ~ce? What you will not sec is nearly one entire half of the moon. The same side always faces the Earth because il takes Ihe same amount of lime I~r the Moon to spin on ils axis (one day) as it lakes piclures of the far to rotate side, around Ihe Earth. which looks quite Spacecraft difl~rcnl arc needed to send from our familiar vision. The The phases of the Moon (A) and the appearaucc of the Moon at Ne~, First Quarler. Full and Last Quarter (B). Last Ouar,er A line: the division surface of the moon. See if you can find closely al the bclween sunlight any of these features and darkness Waxing Gibbous ~ .,.--~ Earth (~,F 1 (0 days) ~~2 {7 days) on the ~ Gibbous Crescent (14 days) (~-~4 (21 cays) First Quar.er Courtesy of: "’Skywalch: Eyes-On Activitiesfor Gellir}gto Know trio Stars.PeterLancastnr-Browrl. Adelburgh. Suffolk.England HI,ION Quarter Day7 (’:i .... i~) Waningu~Qous ..... O " ’ ,,.. Gibbous OF THE MOON First ..... ,t. .;o,1, B I nexl time you look Phases of the Moon As the moonIravels countcrclt)ckwisc ztrotmd lhc Earth (from above), and lhe Earth-Moon system lravcls cotmlerclockwisc around Ihc Sun (from above), Earthlin-s~. arc Ircatcd to zl lighting l)hcnomcntmknownas moonphases, h lakes nearly 28 days for the moonto completely circle the Earth. As the lllOOla travels around Ihc Earth, one side of the moonis always lit unless the earth is blocking tl~e sun’s light, which we call a lunar eclipse. If you look at the Earlh-Moonsystem from afar, you would scc Ihe Earth and Moon lit up the same. PHASES - Crescen.:.. moon is bcsl viewed through a Iclescopc not when it is full, but rather when it is in any oue of its partial phases. This is when you get the most [iclp [roll~ the sun, and can scc the terminalor ~ ~ ,. Day21 ~... Waxing Crescent Sunlight ’ "I,I~ ~w ~OOn :.. ~ ...t...,Waning ....... Cres~n: Sunlight Last Qua~er Courtesy of: "1001Things Everyone Should Know AbouttheUniverse", byWdllam A. Gutsch. Jr. Ph.D.,DoubleDay Dell, New York SOUTH The changing phase of thc mnon as it inures acrnss the sk). The sequence of images is at oneday intervals just after sunset. Whenthe moonis in the direction uf the sun, tin the west) the sun lights up the far side of the moonand the dark side faces us. The dark side may be harely visihle due In "earlhshine’: sunlight reflecting nff the Earth illuminating the Mnnn. Each day a little mnreof the illuminated side becmnesvisible aroundIhe edge of the moonfacing the sun. The illuminated portion appears first as a crescent, then a half disk, then gibbnus, and finally a frill disk wheuthe mounis at opposition R~pposite the sun in the sky, rising at sunset, overhead at midnight). 9