1 NavigationNavigation

2 Line of Position (LOP) using the Sun from run of at least three qualified sights Line of Position (LOP) using the Moon from run of at least three qualified sights Line of Position (LOP) using a Star from run of at least three qualified sights Line of Position (LOP) using a Planet from run of at least three qualified sights Meridian Transit of the Sun from run of at least three sights with one sight within 10 sec of MT 2-body Fix using any two bodies from a run of at least three qualified sights each; taken within 20 mins and intersection of LOP’s not less than 45º Any one of these sights must be reduced and plotted by the Nautical Almanac Sight Reduction (NASR) method. One sight from each of the other three must be reduced and plotted using the Law of Cosines (LOC) method. Sight within 10sec of calculated MT reduced using the Meridian Transit SR form. Selected sights must be reduced and plotted by both the NASR and LOC method Minimum of 21 sights hs between 15º and 75º; LOP with 3.0nm 7 SR Form / 6 CLS SAP Sight Folder Requirements APPENDIX D

3 NavigationNavigation MondayTuesdayWednesdayThursdayFridaySaturdaySunday 31 Mar1 April May

4 Chapter 1 View of our Solar System NavigationNavigation Chapter 2 Sunrise … Sunset

Apparent motion Apparent motion ‘First Point of Aries’ ‘First Point of Aries’ Sidereal Hour Angle (SHA) Sidereal Hour Angle (SHA) Difference between solar & sidereal time Difference between solar & sidereal time Difference between LMT & ZT Difference between LMT & ZT Determine ZT Sun/Moon rise/set Determine ZT Sun/Moon rise/set Determine ZT civil & nautical twilight Determine ZT civil & nautical twilight 5 Learning Objectives

6 Jun 21 Sep 22 Dec 21 Mar 20 Night Sky Solar Time Orbit time: 31,536,000 SI seconds 86, seconds/day -18.1sec +31.1sec -21.3sec +29.9sec

7 SUMMER SOLSTICE Night Sky NP SP Jun 21 Dec 23º 26.1’ N

8 AUTUMNAL EQUINOX Night Sky NP SP Sep 22 Dec 0º 00.0’

9 WINTER SOLSTICE Night Sky NP SP Dec 21 Dec 23º 26.1’ S

10 Mar 20 Dec 0º 00.0’ VERNAL EQUINOX First point of Aries (  ) Night Sky NP SP

11 Night Sky Sidereal Time 23hr 56min sec

12 Celestial Equator Ecliptic  Aries

13 Celestial Equator  Aries N P Dubhe SHA 193° 51.3’ Aries NA1800 GHA 88° 25.8’ G GHA = SHA + GHA 

19 Mar 20xx Mar 20xx Dubhe  – G g   ? ? ? ? Sight Reduction Form

15 VENUS MARS JUPITER SATURN MOON Night Sky

16 Sun – Moon – 4 Planets – 57 Stars South Declination 1 st Magnitude Sirius (-1.5) Canopus (-0.7) Rigil Kentaurus (-0.3) Rigel (0.1) Achernar (0.5) Spica (1.0) Antares (1.0) Fomalhaut (1.2) Acrus (1.3) Adhara (1.5) Gacrux (1.6) Shaula (1.6) Navigator’s Solar System North Declination 1 st Magnitude Arcturus (0.0) Vega (0.0) Betelgeuse (0.1) Capella (0.1) Procyon (0.4) Altair (0.8) Aldebaran (0.9) Regulus (1.1) Pollux (1.1) Deneb (1.3) Bellatrix (1.6) NA

17 Betelgeuse Bellatrix Rigel Alnilam Capella

18 Morning Sights Between beginning of CT and sunrise Evening Sights Between sunset and end CT Horizon, planets and brightest stars visible 0643 – min 1923 – min

19

20 Solar P-hen-omen-a Sunrise (SR) Sunrise (SR) Sunset (SS) Sunset (SS) Twilight Twilight Civil Twilight (CT) Civil Twilight (CT) Nautical Twilight (NT) Nautical Twilight (NT)

21 Local Mean & Zone Time Local Mean Time (LMT) – based on the mean sun with reference to the local celestial meridian. Zone Time (ZT) – based on the nearest meridian with a longitude exactly divisible by 15°. DLo – difference between your Lo and referenced meridian.

22 Local Mean & Zone Time ZM 90° W 97.5° W82.5° W ZD ° W 1814 ZT ? 1814 LMT

23 Local Mean & Zone Time Zone Time: 1814 Location: Lo 92° 42.6’ W 1.FIND ZM: 2.FIND DLo: 3.DLo to TIME: 4.LMT: (15° in 1 hr ; 1° in 4 min ) 92° 43’ – 90° = 2° 43’ = 2.7° 2.7° x 4 min = 10.8 min ; rounded 11 min min = 1803

24 Predicting Phenomena Location: L 48° 20.7’ N Lo 92° 42.6’ W Find LMT for beginning of morning CT. Tab LatLMT CT 50° ° ° 14 min Latitude: 48° 20.7’ N 45° 00.0’ N 3° 20.7’ = 3.35°

25 Predicting Phenomena Diff Tab Lat: 5° Diff LMT: 14 min Diff Lat: 3.35° LMT CT L 45° N 0704 Corr for L 48° 20.7’ N 9 min LMT CT L 48° 20.7’ N

26 Predicting Phenomena LMT CT L 48° 20.7’ N 0713 DLo = DR Lo – ZM Lo 92° 43’ W ZM 90° 00’ W DLo 2° 43’ W = 2.7° 2.7° x 4 min = 10.8 rounded 11 min LMT 0713 DLo (W) + 11 LMT for CT 0724

27 Predicting Phenomena

28 Predicting Phenomena ABOARD MOVING VESSEL “First Estimate” ZT 0000 GPS Position L 45° 26’ N; Lo 11° 39’ W Course 115° T; Speed 9.0kn Tab L 45° N NT = 0627 (Lo 15° W) When do you need to be on deck for morning sights?

29 Predicting Phenomena ABOARD MOVING VESSEL “First Estimate” How far will you travel by tab LMT NT? = 6 hr 27 min = 387 min Plot projected 0627 DR position

30 Predicting Phenomena 45°N 10’ 20’ 50’ 40’11° W40’30’20’10’ 0000 GPS C 115 S Projected L 45° 01.5’ N Lo 10° 46.4’ W 0000 GPS L 45° 26’ N Lo 11° 39’ W

31 Predicting Phenomena ABOARD MOVING VESSEL “First Estimate” Projected DR L 45° 01.5’ N - Lo 10° 46.4’ W Tab LLMT NT 50° N ° N ° 10 min 45° 01.5’ N – 45° 00.0’ N = 1.5’ What’s are the differences in Tab Lat & LMT NT? What’s the difference between EP Lat & Tab L?

32 Predicting Phenomena What’s the LMT NT at projected Lat? LMT NT: = 0627 ABOARD MOVING VESSEL “First Estimate”

33 Predicting Phenomena What’s your DLo? What’s the arc to time conversion? What’s the LMT NT at projected DR? DLo: 15° 00.0’ W – 10° 46.4’ W 4° 13.6’ W = -4.2° 4.2° x 4 min = 16.8 min rounded 17 min LMT NT: 0627 – 17 min = 0610 ABOARD MOVING VESSEL “First Estimate” LMT Projected Lat = 0627

34 Next week bring your calculator or abacus CHAPTER 6 SIGHT PLANNING NavigationNavigation

View of our Solar System Sunrise / Sunset 35 The End