Civil Twilight Duration (sunset to solar depression 6°) at the Prime Meridian, Sea Level, Northern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 20
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Civil Twilight Duration (daytime temporal minutes after sunset) after minutes temporal (daytime Duration Civil Twilight 23.5° N 30° N 100 40° N 45° N
105 50° N 55° N 58° N 59° N 110 60° N 61° N Northward Equinox North Solstice 115 Southward Equinox South Solstice 120
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/ Civil Twilight Duration (sunset to solar depression 6°) at the Prime Meridian, Sea Level, Southern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 20
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95 23.5° S 30° S Civil Twilight Duration (daytime temporal minutes after sunset) after minutes temporal (daytime Duration Civil Twilight 100 40° S 45° S 50° S 55° S 105 58° S 59° S
110 60° S 61° S
Northward Equinox North Solstice 115 Southward Equinox South Solstice 120
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/ Nautical Twilight Duration (sunset to solar depression 12°) at the Prime Meridian, Sea Level, Northern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 45
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125 23.5° N 130 30° N 35° N 135 38° N 140 40° N 145 42° N
150 45° N
Nautical Twilight Duration (daytime temporal minutes after sunset) after minutes temporal (daytime Duration Twilight Nautical 49° N 155 52° N 160 54° N
165 Northward Equinox North Solstice 170 Southward Equinox 175 South Solstice 180
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/ Nautical Twilight Duration (sunset to solar depression 12°) at the Prime Meridian, Sea Level, Southern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 45
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125 23.5° S
130 30° S 35° S 135 38° S 140 40° S 145 42° S
150 45° S
Nautical Twilight Duration (daytime temporal minutes after sunset) after minutes temporal (daytime Duration Twilight Nautical 49° S 155 52° S 160 54° S 165 Northward Equinox North Solstice 170 Southward Equinox 175 South Solstice 180
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/ Astronomical Twilight Duration (sunset to solar depression 18°) at the Prime Meridian, Sea Level, Northern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 70
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120 e temporal minutes after sunset)
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160 23.5° N 30° N Astronomical Twilight Duration (daytim 35° N 38° N 165 40° N 42° N 44° N 46° N 170 47° N 49° N 175 Northward Equinox North Solstice Southward Equinox South Solstice 180
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/ Astronomical Twilight Duration (sunset to solar depression 18°) at the Prime Meridian, Sea Level, Southern Hemisphere (March 1, 2007 to March 31, 2008) Mar 1 Mar 15 Mar 29 Apr 12 Apr 26 May 10 May 24 7 Jun 21 Jun Jul 5 Jul 19 Aug 2 Aug 16 Aug 30 Sep 13 Sep 27 11 Oct 25 Oct Nov 8 Nov 22 Dec 6 Dec 20 Jan 3 Jan 17 Jan 31 14 Feb 28 Feb Mar 13 Mar 27 70
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120 e temporal minutes after sunset)
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160 Astronomical Twilight Duration (daytim 23.5° S 30° S 165 35° S 38° S 40° S 42° S 170 44° S 46° S 47° S 49° S 175 Northward Equinox North Solstice Southward Equinox South Solstice 180
Analysis by Dr. Irv Bromberg, University of Toronto, Canada http://www.sym454.org/twilight/