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Text File  |  1985-11-20  |  20KB  |  523 lines
  1. 0660103030566
  2. 9[....................................................]
  3.  
  4.  
  5. CadenzaAstroCal(Version1.8,October6,1988)
  6.  
  7.  
  8. ProgramFeatures
  9.  
  10. Thisprogramgenerates(foranygivenyear)acalendarcontaining
  11. thefollowinginformation:
  12.  
  13. 1.   Timesofsunrise,sunset,moonrise,andmoonsetforeachday
  14. 2.   TimesanddatesofMoonphases
  15. 3.   Timesanddatesofsolarandlunareclipses
  16. 4.   Timesanddatesofsolsticesandequinoxes
  17.  
  18. Inadditiontothiscalendar,theprogramcangenerate:
  19.  
  20. 1.   Areportofalllunarorsolareclipsesforarangeofyears
  21. 2.   Areportofplanetviewinginformationforaspecifiedyear
  22. 3.   Areportofperihelionsandaphelionsofplanetsfora
  23.      rangeofyears
  24. 4.   AreportofperigeesandapogeesoftheMoonforaspecified
  25.      year
  26. 5.   AreportofthedatesofEasterforarangeofyears
  27. 6.   AdiagramofthepositionsofJupiter'sbright(Galilean)
  28.      moons.
  29.  
  30. Thecalendarandreportsareallcustomizedfortheuser's
  31. location.Alltimesanddatesareinlocaltime.
  32.  
  33. Thecalendarandreportscanbeprintedonaprinterorlistedon
  34. thecomputerscreen.
  35.  
  36.  
  37. HardwareRequirements
  38.  
  39. ThisprogramshouldrunonanyAtariSTcomputerwithamonochrome
  40. orcolormonitor.Thisprogramrunsoncolormonitorsinmedium
  41. resolutiononly(pleaseseetheBugssectionbelow).Ofcourse,
  42. userswantingtoprintoutcalendarsandreportswillneeda
  43. printer.
  44.  
  45.  
  46. Menus
  47.  
  48. AstroCalhasthefollowingmenus:"Desk","DescribeLocation",
  49. "GenerateReport","File","Display",and"Help".
  50.  
  51. The"Desk"menucanbeusedtorundeskaccessoryprograms,andto
  52. seethe"introductionbox"ofthisprogram.
  53.  
  54. The"DescribeLocation"menuisusedtospecifyone'slocation(in
  55. latitudeandlongitude),andthedifferencebetweenlocaltimeand
  56. UT(universaltime(sometimescalledGMT(GreenwichMeanTime)).
  57.  
  58. The"GenerateReport"menuhaseightsubmenus:"Calendar","Lunar
  59. Eclipses","SolarEclipses","PlanetViewInfo","Planet
  60. Distance","MoonDistance","DatesofEaster",and"Jupiter
  61. Moons".
  62.  
  63. The"File"menuhasonlyonesubmenu,labeled"Quit".This
  64. submenuisselectedtoquittheentireprogram.
  65.  
  66. The"Display"menuhastwosubmenus,"Scroll"and"Stop".Ifyou
  67. selectthe"Stop"submenu,theprogramwillwaitforyoutotype
  68. theRETURNkeyaftereachpageoftextislistedonthedisplay
  69. screen.Ifyouwouldpreferthattheprogramcontinuouslywrite
  70. textonthedisplayscreenwithoutstopping,selectthe"Scroll"
  71. submenu.The"Display"menudoesnotaffecttheprintingof
  72. calendarsandreportsonaprinter.
  73.  
  74. The"Help"menuisusedtogetbasicinformationaboutthe
  75. program.
  76.  
  77.  
  78. GettingStarted
  79.  
  80. Firstofallyouwillneedtoprovidetheprogramwithsome
  81. informationaboutyourlocationandlocaltime.Thisinformation
  82. isrequiredtoallowtheprogramtocustomizeitsoutputforyour
  83. locationandtimezone.
  84.  
  85. Selectthe"DescribeLocation"menuwiththemouse.Thenselect
  86. the"DescribeLocation"submenu.Atthispointyoushouldseea
  87. "dialogbox"allowingyoutospecifyyourcity'sname,your
  88. latitudeandlongitude,andthedifferencebetweenyourlocaltime
  89. andUT.
  90.  
  91. Typethenameofyourcityinthespacelabeled"LocationName".
  92. Typeinyourlatitudeandlongitudeintheappropriatespaces.
  93. Notethatlatitudeandlongitudemustbeenteredasdecimal
  94. degrees.Toconvertanangleexpressedindegrees,minutes,and
  95. secondsformtodecimaldegrees,usethefollowingformula:
  96.  
  97. decimaldegrees=degrees+minutes/60+seconds/360
  98.  
  99. Forexample,ifyouknowthatyourlatitudeis32degrees,12
  100. minutes,and44seconds,youwillneedtotypeinalatitudeof
  101. 32.21since:
  102.  
  103. 32+12/60+44/3600=32.21(rounded)
  104.  
  105. Ifyoulivenorthoftheequator,selectthebuttonlabeled
  106. "North".Otherwiseselect"South".
  107.  
  108. Inthesameway,enteryourlongitudeindecimaldegrees,and
  109. selectthe"West"buttonifyoulivewestofGreenwich,England,
  110. or"East"otherwise.
  111.  
  112. Finally,enterthenumberofhoursthatyoumustaddtoUTto
  113. converttoyourlocaltime.IfyoumustsubtractfromUTtoget
  114. yourlocaltime,enteranegativenumber.Youmayentera
  115. fractionalnumber(e.g.4.5).
  116.  
  117. UsersintheUSAcanusethefollowingtable:
  118.  
  119. AtlanticTimeZone                 LocalTime=UT+-4hours
  120. EasternTimeZone                  LocalTime=UT+-5hours
  121. CentralTimeZone                  LocalTime=UT+-6hours
  122. MountainTimeZone                 LocalTime=UT+-7hours
  123. PacificTimeZone                  LocalTime=UT+-8hours
  124. MostofAlaska                     LocalTime=UT+-9hours
  125. HawaiiTimeZone                   LocalTime=UT+-10hours
  126.  
  127.  
  128. Oncethisinformationisentered,selectthebuttonlabeled
  129. "Done".Thisinformationwillbesavedinadiskfile(named
  130. astrocal.dat)andneednotbeenteredagain.
  131.  
  132. NotethatAstroCalgivesalltimesanddatesinlocalstandard
  133. time,neverinDaylightSavingsTimeorSummerTime.
  134.  
  135. Nowthatyou'vespecifiedyourlocation,youcangeneratean
  136. astronomicalcalendarorareport.
  137.  
  138. Noteaboutenteringyears:ifyouwantacalendarorreportfor
  139. theyear1988,enter1988,not88.Negativeyears(i.e.B.C.)can
  140. beentered.
  141.  
  142.  
  143. GeneratinganAstronomicalCalendar
  144.  
  145. Selectthe"GenerateReport"menu,andthenthe"Calendar"
  146. submenu.Atthispointyoushouldseeadialogboxallowingyou
  147. tospecifytheyearofthecalendar,thestartingmonthofthe
  148. calendar,andwhetherthecalendarshouldbeprintedonyour
  149. printeroronthecomputerscreen.Onceyou'vegiventhis
  150. information,pressthe"Done"button,andthecalendarwillbe
  151. generated.Ifyouchangeyourmind,pressthebuttonlabeled
  152. "Cancel",andthecalendarwillnotbegenerated.Preparingan
  153. astronomicalcalendarwilltakeaboutonehour.
  154.  
  155. Thecalendarwillcontainseveralabbreviationswhichare
  156. explainedintheAbbreviationssectionlaterinthisdocument.
  157.  
  158.  
  159. EquinoxesandSolsticesintheNorthernHemisphere
  160.  
  161. ThecelestialequatoristheplanedescribedbytheEarth's
  162. equator.TheeclipticistheapparentpathoftheSunacrossthe
  163. skyduringoneyear.
  164.  
  165.  
  166. Equinoxesoccurwhentheeclipticcrossesthroughthecelestial
  167. equator.AttheMarchEquinoxtheSunappearstocrossthe
  168. celestialequatoronitsjourneynorth.TheSeptemberEquinox
  169. happenswhentheSuncrossesthecelestialequatorgoingsouth.
  170.  
  171. Solsticesoccurwhentheeclipticismaximallynorthorsouthof
  172. thecelestialequator.AttheJuneSolsticetheSunisasfar
  173. northofthecelestialequatoraspossible.AttheDecember
  174. SolsticetheSunisasfarsouthaspossible.
  175.  
  176. SpringbeginsattheMarchEquinox,SummerattheJuneSolstice,
  177. FallattheSeptemberEquinox,andWinterattheDecember
  178. Solstice.
  179.  
  180. Forthesouthernhemisphere,switchnorthandsouth,summerand
  181. winter,andfallandspringinthepreviousthreeparagraphs.
  182.  
  183.  
  184. GeneratinganEclipseReport
  185.  
  186. Selectthe"GenerateReport"menuwiththemouse,andthenselect
  187. the"LunarEclipses"or"SolarEclipses"submenu.Atthispoint
  188. youshouldseeadialogboxpromptingyoufortherangeofyears
  189. ofthereport,andwhetherthereportshouldbeprintedonyour
  190. printerorlistedonyourdisplayscreen.Press"Done"when
  191. you'veenteredalloftheinformation,orpress"Cancel"toquit.
  192.  
  193.  
  194. InterpretingaLunarEclipseReport
  195.  
  196. Duringalunareclipse,allobserversthatcanseethemoonwill
  197. seethesamepart(i.e.moonentersshadow,maximumeclipse,moon
  198. leavesshadow)oftheeclipseatthesameinstant.Thusforeach
  199. eclipseintheeclipsereport,youwillbeabletoviewagiven
  200. partofthateclipseifitoccursbetweenth