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Nautical Almanac

2017

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The Nautical Almanac 2017

Warning and Terms of Usage:

The following pages have been generated by a computer program. Complex computer programs usuallyhave bugs and may produce wrong data. The data in this Nautical Almanac is believed to be accurate butno warranty is given for its correctness.Use this Nautical Almanac only for training and exercising!

Compiled by Erik De Man ([email protected]) on Mon Sep 26 08:30:32 2016

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Introduction

This Nautical Almanac contains the Ephemerides of the Sun, the Moon, Venus, Mars, Jupiter and Saturn.It is designed for determination of Position (geographical Latitude and Longitude) from astronomicalobservations (Altitude of Celestial Objects).

The data compiled in this Nautical Almanac is based on calculations done with the software package"NOVAS" from the U.S. Naval Observatory (http://aa.usno.navy.mil/AA/software). The basic ephemeridesare taken from the "DE405" files published by the Jet Propulsion Laboratory (http://ssd.jpl.nasa.gov).

For the astrodynamical calculations, the following values for "delta T" (the difference between terrestrialtime realized by atomic clocks and UT defined by the irregular rotation of the Earth) have been used:JanFebMar

AprMayJun

JulAugSep

OctNovDec

: 68.6

: 68.7

: 68.7

: 68.8

: 68.8

: 68.9

: 68.9

: 69.0

: 69.0

: 69.1

: 69.1

: 69.2

s

s

s

s

s

s

s

s

s

s

s

s

NOTICE: This Nautical Almanac uses a slightly different approach for the interpolation of the integral-hour values ofGreenwhich Hour Angle and Declination, compared to the techniques used in most commercially availableAlmanacs.For more information please refer to the following web site: "http://www.siranah.de/"

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Positions of the Celestial Objects

The charts on the following pages show the position of the Celestial Objects used in this Nautical Almanacrelative to the stars (celestial background). The charts can be used to find the location of the planets andalso for the planning of astronomical observations.

The charts are available for each month of the year. Each chart has two parts showing a part of the celestialsphere around the ecliptic. Notice that the position of the Celestial Equator (Declination = 0°) is shifted inthe two different parts of a chart.

The changing position of a Celestial Object through the month is drawn as a solid line (not for the Moon).Marker tics are shown to indicate the 1st, 8th 15th, 22nd and 29th day of the month (at 12:00 UT).For Jupiter and Saturn only the first day of the month is marked since their apparent positions do notchange significantly over the period of one month.The position of the Moon is shown by a small circle for each individual day of the month. Notice that thecircles are much larger than the apparent size of the Moon.

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0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

January 2017

5

6

7

89

10111213

14

15

16

17 29

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur

altairenifras alhague

fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES1

2

3

4

17

18

19

20

2122

23242526

2728

29

30

31

11815

Sun

2229

11

8

15

Venus

22

29

118

15

Mars

2229

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

February 2017

1

2

3

4

5678

910

11

12

13

28

815

Venus

22

118

15

Mars

22

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

14

15

16

1718

1920212223

2425

26

27

118

15

Sun

22

11

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

March 2017

1

2

3

45

6789

10

11

12

28

29

30

31

2229

118 15

Venus22

29118

15

Mars

2229

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

13

14

15

16

1718

1920212223

24

25

26

27

118

15

Sun

22

29

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

April 2017

1234

56

7

8

924

25

26

27

282930

118

15

Sun

2229

29

118

15

Mars

2229

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

9

10

11

12

1314

15161718

1920

21

22

23

11815

Venus2229

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

May 2017

12

3

4

5

6

21

22

23

24

2526

272829

30

31

118

15

Sun

2229

11815

Venus

2229

11815

Mars

2229

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

7

8

9

1011

1213141516

1718

19

20

11

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

June 2017

1

2

18

19

20

21

22232425

26

27

28

29

11815

Sun

2229

118

15

Venus

2229

11815

Mars

2229

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

3

4

5

6

78

910111213

14

15

16

17

30

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

July 2017

15

16

17

18

1920

212223

24

25

26

27

11815

Sun22

2911

815

Venus

222911815

Mars2229

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

1

2

3

45

6789

1011

12

13

14

27

28

29

30

31

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

August 2017

11

12

13

14

1516

17181920

21

22

23

118

15

Sun22

29

11815

Venus22

29118

15

Mars22

29

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES1

23456

78

9

10

24

25

26

27

2829

3031

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

September 2017

7

8

9

10

1112

13141516

17

18

19

118

15

Sun22

118

15

Venus22

29

118

15

Mars22

29

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

123

4

5

6

20

21

22

23

2425

26272829

30

2229

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

October 2017

5

6

7

8

9101112

1314

15

16

17

11

8

15

Venus

118

15

Mars22

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES1

2

3

4

17

18

19

20

2122

2324252627

2829

30

31

118

15

Sun22

29

15

Venus22

29

2229

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

November 2017

1

2

3

4

56

789

10

11

12

13

29

30

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

14

15

16

17

1819

2021222324

25

26

27

28

118

15

Sun22

29

11

8

15

Venus2229

118

15

Mars22

29

1

Jupiter

1

Saturn

0

10

20

30

40

0

10

20

0

10

20

30

40

0

10

20

° °

N N

S S

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

180° 165° 150° 135° 120° 105° 90° 75° 60° 45° 30° 15° 0°

Right Ascension

sirius

procyon

pollux

castor

rigel

beteigeuse

aldebaran

hamel

regulusdenebola

deneb kaitos

LEO

GEMINITAURUS

ARIES

December 2017

1

2

3456

7

8

9

10

26

27

28

29

3031

0

10

20

0

10

20

30

40

0

10

20

0

10

20

30

40

° °

N N

S S

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

360° 345° 330° 315° 300° 285° 270° 255° 240° 225° 210° 195° 180°

arctur


fomalhaut

antares

spica

unuk

VIRGO

LIBRA

SCORPIOSAGITTARIUS

CAPRICORN

AQUARIUS

PISCES

11

12

13

14

1516

17181920

2122

23

24

25

11815

Sun

2229

118

15

Venus2229

118

15

Mars22

291

Jupiter1

Saturn

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Phases of the Moon

The following table lists the phases of the Moon through the year 2017. The table shows the day and theapproximate time (in UT) when the particular lunar phases occur. The calculations are based on thedifference between the GHA of the Sun and the GHA of the Moon (Delta_GHA = GHA_sun - GHA_moon).The constellations "new moon", "first quarter", "full Moon" and "last quarter" are obtained when Delta_GHAis equal to 0°, 90°, 180° and 270° respectively.

January

February

March

April

May

June

July

August

September

October

November

December

New Moon First Quarter Full Moon Last Quarter

Thu 5 22:17 Thu 12 12:34 Fri 20 04:31

Sat 28 01:18

Sat 4 10:41 Sat 11 01:11 Sun 19 02:16

Sun 26 14:39

Sun 5 14:46 Sun 12 13:29 Mon 20 15:54

Tue 28 00:45

Mon 3 15:20 Tue 11 02:54 Wed 19 02:35

Wed 26 09:34

Tue 2 18:30 Wed 10 18:44 Thu 18 15:27

Thu 25 18:12

Thu 1 05:34 Fri 9 12:18 Sat 17 08:08

Sat 24 02:39

Sat 1 01:15 Sun 9 04:58 Sun 16 23:29

Sun 23 10:33 Sun 30 22:19

Mon 7 18:41 Tue 15 07:25

Mon 21 18:13 Tue 29 14:00

Wed 6 05:39 Wed 13 08:32

Wed 20 03:10 Thu 28 01:24

Thu 5 15:42 Thu 12 07:51

Thu 19 15:37 Fri 27 13:32

Sat 4 02:36 Fri 10 11:39

Sat 18 09:07 Sun 26 07:39

Sun 3 14:43 Sun 10 01:42

Mon 18 06:17 Tue 26 07:45

Tidal Phase spring neap spring neap

Lunar Phases and TidesThe lunar phases may be used to roughly estimate the occurrence of spring and neap tides. Spring tideoccurs around new and full moon. Neap tide occurs around the first and last quarter.Each tidal region on Earth, has a characteristic "tidal delay" which, specifies the time difference betweenthe occurrence of a particular lunar phase and the occurrence of the resulting tidal phase. The tidal delaycan be a couple of hours for the open seas, or up to several days for branched tidal waters such as parts ofthe North Sea.

Reliable tidal predictions are obtained from a Tidal Almanac.

Lunar Eclipses

An eclipse of the Moon - or lunar eclipse - can only occur at Full Moon, and only if the Moon passes throughsome portion of the Earth’s shadow. The Earth’s shadow is composed of two concentric cone-shapedcomponents. The outer or penumbral shadow is a region where the Earth blocks part (but not all) of theSun’s light from reaching the Moon. The inner or umbral shadow is a region where the Earth blocks alldirect sunlight from reaching the Moon. Based on this, three types of lunar eclipses are distinguised:1. Penumbral Lunar Eclipse: the Moon passes through the Earth’s penumbral shadow. These kind of

eclipses are subtle and very difficult to observe.2. Partial Lunar Eclipse: a part of the Moon passes through the Earth’s umbral shadow.3. Total Lunar Eclipse: the Moon passes entirely through the Earth’s umbral shadow. During this phase of

the eclipse the Moon will take a vibrant range of dark red and brown colors.

NOTICE: Eclipse contact times depend on the angular diameters of the Sun and Moon. The calculationsin this Almanac are based on a perfect circular form for the limb of the Moon, and do not take into accounteffects of refraction of the sunlight in the Earth atmosphere. Since this is only an approximation of reality,contact times are accurate only within a couple of minutes.

The following lunar eclipses may be observed during the year 2017:

February 11 : a penumbral lunar eclipse begin [ Feb 10, 22:33 UT ] / end [ Feb 11, 02:56 UT ]

August 7 : a partial lunar eclipse begin [ Aug 7, 15:49 UT ] / end [ Aug 7, 20:54 UT ]

12

67

umbra

August 7

August 7penumbra

1 - 15:49 UT begin of penumbral eclipse

2 - 17:24 UT begin of partial eclipse

18:21 UT moment of greatest eclipse

6 - 19:19 UT end of partial eclipse

7 - 20:54 UT end of penumbral eclipse

Rp = 1.2127°

Ru = 0.6765°

Solar Eclipses

An eclipse of the Sun - or solar eclipse - can only occur at New Moon, and only if the Earth passes throughsome portion of the Moon’s shadow. Seen from the Earth, the Moon passes in front of the Sun and thusa part - or all - of the light of the Sun is eclipsed. The shadow cast by the Moon is composed of twoconcentric cone-shaped components. The outer or shadow zone is the region where thepenumbral

Moon blocks a part of the sunlight. The inner or shadow zone is a region where the Moon blocksumbral

all sunlight. Based on this, three types of solar eclipes may be distinguised:1. Total solar eclipse: occurs when the umbra of the Moon’s shadow touches a region on the surface of the

Earth.2. Partial solar eclipse: occurs when the penumbra of the Moon’s shadow passes over a region on the

Earth’s surface.3. Annular solar eclipse: occurs when a region on the Earth’s surface is in line with the umbra, but the

distances are such that the tip of the umbra does not reach the Earth’s surface

Because of the relative sizes of the Moon and Sun and their specific distances from the Earth, only a smallpart of the Earth surface is covered by the Moon shadow during a solar eclipse. Especially the path oftotality is usually very narrow (a few hundreds of kilometers across). A much broader region is covered bythe penumbral shadow of the Moon. However, an observer in this region will see only a partial solar eclipse.

The appearance of a specific solar eclipse can be summarized conveniently by mapping the path of totalityand the region covered by the penumbral shadow of the Moon for the complete duration the eclipse. Thelines of constant time, included in the charts, indicate the instances of greatest eclipse.

Warning: never look directly at the Sun without proper eye protection, even during an eclipse. Even whenthe Sun is partially covered, your eyes can be seriously damaged by looking directly at it. Sunglasses arenot an adequate eye protection for viewing the Sun.

The following solar eclipses may be observed during the year 2017:

February 26 : annular solar eclipse begin [ Feb 26, 12:10 UT ] / end [ Feb 26, 17:36 UT ]

60°

45°

30°

15°

0°

15°

30°

45°

60°

N

S135° 120° 105° 090° 075° 060° 045° 030° 015° 000° 015° 030° 045° 060° 075°

P1

P4

13:30

14:00 14:30 15:00

15:30

16:00

16:30

Circumstances at Moment of Greatest Eclipse Fist Contacts (P1/U1) Last Contacts (U4/P4)Time: 14:53 UT Penumbra Penumbra

Location: S 34.4 W 031.2 12:10 UT 17:36 UT

August 21 : total solar eclipse begin [ Aug 21, 15:47 UT ] / end [ Aug 21, 21:05 UT ]

60°

45°

30°

15°

0°

15°

30°

45°

60°

N

S180° 165° 150° 135° 120° 105° 090° 075° 060° 045° 030° 015° 000° 015°

P1

P4

17:00

17:30 18:00 18:30

19:00

19:30

20:00

Circumstances at Moment of Greatest Eclipse Fist Contacts (P1/U1) Last Contacts (U4/P4)Time: 18:26 UT Duration (full): 0.0 min Penumbra Umbra Umbra Penumbra

Location: N 36.7 W 087.7 Path Width: 115 km 15:47 UT 16:48 UT 20:03 UT 21:05 UT

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Equation of Time

The "Equation of Time" is the difference between the Apparent Solar Time and the Mean Solar Time at thePrime Meridian of Greenwich. The value for the Equation of Time (EoT) for a specific day can be obtainedfrom the Nautical Almanac. The section of the Sun records the "Greenwich Culmination Time" (GCT), whichis the UT time at which the Geographical Position of the Sun transits the Prime Meridian of Greenwich. Thisis also the UT time of Local Apparent Noon for the Prime Meridian. Thus, the value for the Equation of Timeis obtained from: EoT = 12:00:00 - GCT.

Examples:

GCT = 11:57:23 GCT = 12:01:57EoT = 12:00:00 - 11:57:23 = +00:02:37 EoT = 12:00:00 - 12:01:57 = -00:01:57

Notice that EoT has a sign: positive if the Sun "culminates" before 12 UT (then Apparent Time is "leading"Mean Time) and negative if the Sun "culminates" after 12 UT (then Apparent Time is "lagging" Mean Time).

The next graph shows the values for the "Equation of Time" (in Minutes) over the year 2017.

-16

-12

-8

-4

0

4

8

12

16

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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Nautical Almanac

The following pages contain the coordinates of the Geographical Position (in Greenwich Hour Angle andDeclination) for each integral hour of the year for the recorded celestial objects. Each page compiles thecomplete Almanac data for one day of the year. The time used in this Almanac is Universal Time (UT).

NOTICE: This Nautical Almanac uses a slightly different approach for the interpolation of the integral-hour values ofGreenwhich Hour Angle and Declination, compared to the techniques used in most commercially availableAlmanacs.For more information please refer to the following web site: "http://www.siranah.de/"

Abbreviations used in the Almanac tables:

UT Universal Time

GHA Greenwich Hour Angle ° [degrees]

Dec Declination ° [degrees]

ddGHA the increment of the GHA value for the next hour of time, additional to the "linear" increment of 15°/h

’ [minutes of arc]

dDec the increment of the Dec value for the next hour of time ’ [minutes of arc]

SD Semi-Diameter of the celestial object ’ [minutes of arc]

HP Horizontal Parallax ’ [minutes of arc]

a the "age" of the Moon, according to the following scheme: a = 0.00 : new moona = 0.25 : first quartera = 0.50 : full moona = 0.75 : last quarter

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