The equation of time Equation of time, 2054 Every day of 2054 at 12:00 UTC: how far a sundial runs ahead of the clock (early) or behind it (late), the Sun’s declination, and how much the day from one solar noon to the next differs from 24 hours.
The sundial runs furthest ahead around Nov 3, by 16 min 28 s, and furthest behind aroundFeb 11, by 14 min 8 s.
‹ 2053Today CSV 2055 ›
January Date Sundial Declination Solar day Thu, Jan 1 3:36 late 22.95° S +28.1 s Fri, Jan 2 4:04 late 22.86° S +27.8 s Sat, Jan 3 4:31 late 22.76° S +27.4 s Sun, Jan 4 4:58 late 22.66° S +27.0 s Mon, Jan 5 5:25 late 22.55° S +26.6 s Tue, Jan 6 5:52 late 22.43° S +26.1 s Wed, Jan 7 6:18 late 22.30° S +25.6 s Thu, Jan 8 6:43 late 22.16° S +25.1 s Fri, Jan 9 7:08 late 22.02° S +24.6 s Sat, Jan 10 7:32 late 21.87° S +24.0 s Sun, Jan 11 7:56 late 21.72° S +23.4 s Mon, Jan 12 8:19 late 21.55° S +22.8 s Tue, Jan 13 8:42 late 21.38° S +22.2 s Wed, Jan 14 9:04 late 21.20° S +21.5 s Thu, Jan 15 9:25 late 21.02° S +20.9 s Fri, Jan 16 9:46 late 20.83° S +20.2 s Sat, Jan 17 10:05 late 20.63° S +19.5 s Sun, Jan 18 10:24 late 20.43° S +18.8 s Mon, Jan 19 10:43 late 20.22° S +18.0 s Tue, Jan 20 11:00 late 20.00° S +17.3 s Wed, Jan 21 11:17 late 19.78° S +16.5 s Thu, Jan 22 11:33 late 19.55° S +15.8 s Fri, Jan 23 11:49 late 19.32° S +15.0 s Sat, Jan 24 12:03 late 19.08° S +14.2 s Sun, Jan 25 12:17 late 18.83° S +13.4 s Mon, Jan 26 12:30 late 18.58° S +12.6 s Tue, Jan 27 12:42 late 18.32° S +11.8 s Wed, Jan 28 12:53 late 18.06° S +11.0 s Thu, Jan 29 13:04 late 17.79° S +10.2 s Fri, Jan 30 13:13 late 17.52° S +9.4 s Sat, Jan 31 13:22 late 17.24° S +8.6 s
February Date Sundial Declination Solar day Sun, Feb 1 13:31 late 16.95° S +7.7 s Mon, Feb 2 13:38 late 16.66° S +6.9 s Tue, Feb 3 13:44 late 16.37° S +6.1 s Wed, Feb 4 13:50 late 16.07° S +5.3 s Thu, Feb 5 13:55 late 15.77° S +4.5 s Fri, Feb 6 13:59 late 15.46° S +3.7 s Sat, Feb 7 14:03 late 15.14° S +2.9 s Sun, Feb 8 14:05 late 14.83° S +2.1 s Mon, Feb 9 14:07 late 14.51° S +1.3 s Tue, Feb 10 14:08 late 14.18° S +0.6 s Wed, Feb 11 14:08 late 13.85° S −0.2 s Thu, Feb 12 14:08 late 13.52° S −1.0 s Fri, Feb 13 14:07 late 13.18° S −1.7 s Sat, Feb 14 14:05 late 12.84° S −2.4 s Sun, Feb 15 14:02 late 12.50° S −3.2 s Mon, Feb 16 13:58 late 12.15° S −3.9 s Tue, Feb 17 13:54 late 11.80° S −4.6 s Wed, Feb 18 13:49 late 11.45° S −5.3 s Thu, Feb 19 13:43 late 11.09° S −5.9 s Fri, Feb 20 13:37 late 10.74° S −6.6 s Sat, Feb 21 13:30 late 10.37° S −7.2 s Sun, Feb 22 13:22 late 10.01° S −7.8 s Mon, Feb 23 13:14 late 9.64° S −8.4 s Tue, Feb 24 13:05 late 9.27° S −9.1 s Wed, Feb 25 12:56 late 8.90° S −9.6 s Thu, Feb 26 12:46 late 8.53° S −10.2 s Fri, Feb 27 12:35 late 8.15° S −10.7 s Sat, Feb 28 12:24 late 7.77° S −11.3 s
March Date Sundial Declination Solar day Sun, Mar 1 12:13 late 7.39° S −11.8 s Mon, Mar 2 12:01 late 7.01° S −12.2 s Tue, Mar 3 11:48 late 6.63° S −12.7 s Wed, Mar 4 11:36 late 6.24° S −13.2 s Thu, Mar 5 11:22 late 5.86° S −13.6 s Fri, Mar 6 11:09 late 5.47° S −14.0 s Sat, Mar 7 10:54 late 5.08° S −14.4 s Sun, Mar 8 10:40 late 4.69° S −14.8 s Mon, Mar 9 10:25 late 4.30° S −15.1 s Tue, Mar 10 10:10 late 3.91° S −15.5 s Wed, Mar 11 9:54 late 3.51° S −15.8 s Thu, Mar 12 9:38 late 3.12° S −16.1 s Fri, Mar 13 9:22 late 2.73° S −16.3 s Sat, Mar 14 9:06 late 2.33° S −16.6 s Sun, Mar 15 8:49 late 1.94° S −16.8 s Mon, Mar 16 8:32 late 1.54° S −17.0 s Tue, Mar 17 8:15 late 1.15° S −17.2 s Wed, Mar 18 7:58 late 0.75° S −17.4 s Thu, Mar 19 7:40 late 0.35° S −17.6 s Fri, Mar 20 7:23 late 0.04° N −17.7 s Sat, Mar 21 7:05 late 0.43° N −17.8 s Sun, Mar 22 6:47 late 0.83° N −17.9 s Mon, Mar 23 6:29 late 1.22° N −17.9 s Tue, Mar 24 6:11 late 1.62° N −18.0 s Wed, Mar 25 5:53 late 2.01° N −18.0 s Thu, Mar 26 5:35 late 2.40° N −18.0 s Fri, Mar 27 5:16 late 2.79° N −18.0 s Sat, Mar 28 4:58 late 3.18° N −18.0 s Sun, Mar 29 4:40 late 3.57° N −17.9 s Mon, Mar 30 4:22 late 3.96° N −17.9 s Tue, Mar 31 4:05 late 4.35° N −17.8 s
April Date Sundial Declination Solar day Wed, Apr 1 3:47 late 4.74° N −17.7 s Thu, Apr 2 3:29 late 5.12° N −17.6 s Fri, Apr 3 3:12 late 5.50° N −17.4 s Sat, Apr 4 2:55 late 5.88° N −17.2 s Sun, Apr 5 2:37 late 6.26° N −17.1 s Mon, Apr 6 2:21 late 6.64° N −16.9 s Tue, Apr 7 2:04 late 7.02° N −16.6 s Wed, Apr 8 1:48 late 7.39° N −16.4 s Thu, Apr 9 1:31 late 7.76° N −16.1 s Fri, Apr 10 1:15 late 8.13° N −15.9 s Sat, Apr 11 1:00 late 8.50° N −15.6 s Sun, Apr 12 0:44 late 8.87° N −15.3 s Mon, Apr 13 0:29 late 9.23° N −14.9 s Tue, Apr 14 0:15 late 9.59° N −14.6 s Wed, Apr 15 0:00 9.95° N −14.3 s Thu, Apr 16 0:14 early 10.30° N −13.9 s Fri, Apr 17 0:28 early 10.65° N −13.5 s Sat, Apr 18 0:41 early 11.00° N −13.1 s Sun, Apr 19 0:54 early 11.35° N −12.7 s Mon, Apr 20 1:07 early 11.69° N −12.3 s Tue, Apr 21 1:19 early 12.03° N −11.8 s Wed, Apr 22 1:31 early 12.37° N −11.4 s Thu, Apr 23 1:42 early 12.70° N −10.9 s Fri, Apr 24 1:53 early 13.03° N −10.5 s Sat, Apr 25 2:03 early 13.36° N −10.0 s Sun, Apr 26 2:13 early 13.68° N −9.5 s Mon, Apr 27 2:22 early 13.99° N −9.0 s Tue, Apr 28 2:31 early 14.31° N −8.5 s Wed, Apr 29 2:39 early 14.62° N −8.0 s Thu, Apr 30 2:47 early 14.93° N −7.4 s
May Date Sundial Declination Solar day Fri, May 1 2:54 early 15.23° N −6.9 s Sat, May 2 3:00 early 15.53° N −6.3 s Sun, May 3 3:06 early 15.82° N −5.8 s Mon, May 4 3:12 early 16.11° N −5.2 s Tue, May 5 3:17 early 16.40° N −4.7 s Wed, May 6 3:21 early 16.68° N −4.1 s Thu, May 7 3:25 early 16.95° N −3.5 s Fri, May 8 3:28 early 17.22° N −3.0 s Sat, May 9 3:31 early 17.49° N −2.4 s Sun, May 10 3:33 early 17.75° N −1.8 s Mon, May 11 3:34 early 18.01° N −1.3 s Tue, May 12 3:35 early 18.26° N −0.7 s Wed, May 13 3:35 early 18.51° N −0.1 s Thu, May 14 3:35 early 18.75° N +0.4 s Fri, May 15 3:35 early 18.98° N +1.0 s Sat, May 16 3:33 early 19.21° N +1.6 s Sun, May 17 3:32 early 19.44° N +2.1 s Mon, May 18 3:29 early 19.66° N +2.7 s Tue, May 19 3:26 early 19.87° N +3.2 s Wed, May 20 3:23 early 20.08° N +3.8 s Thu, May 21 3:19 early 20.28° N +4.3 s Fri, May 22 3:15 early 20.48° N +4.8 s Sat, May 23 3:10 early 20.67° N +5.3 s Sun, May 24 3:04 early 20.86° N +5.8 s Mon, May 25 2:58 early 21.04° N +6.3 s Tue, May 26 2:52 early 21.21° N +6.8 s Wed, May 27 2:45 early 21.38° N +7.3 s Thu, May 28 2:37 early 21.54° N +7.7 s Fri, May 29 2:29 early 21.69° N +8.2 s Sat, May 30 2:21 early 21.84° N +8.6 s Sun, May 31 2:12 early 21.98° N +9.0 s
June Date Sundial Declination Solar day Mon, Jun 1 2:03 early 22.12° N +9.4 s Tue, Jun 2 1:53 early 22.25° N +9.8 s Wed, Jun 3 1:43 early 22.37° N +10.1 s Thu, Jun 4 1:33 early 22.48° N +10.5 s Fri, Jun 5 1:22 early 22.59° N +10.8 s Sat, Jun 6 1:11 early 22.70° N +11.1 s Sun, Jun 7 1:00 early 22.79° N +11.4 s Mon, Jun 8 0:48 early 22.88° N +11.7 s Tue, Jun 9 0:36 early 22.97° N +11.9 s Wed, Jun 10 0:24 early 23.04° N +12.1 s Thu, Jun 11 0:12 early 23.11° N +12.3 s Fri, Jun 12 0:01 late 23.17° N +12.5 s Sat, Jun 13 0:13 late 23.23° N +12.7 s Sun, Jun 14 0:26 late 23.28° N +12.8 s Mon, Jun 15 0:39 late 23.32° N +12.9 s Tue, Jun 16 0:52 late 23.36° N +13.0 s Wed, Jun 17 1:05 late 23.38° N +13.0 s Thu, Jun 18 1:18 late 23.41° N +13.1 s Fri, Jun 19 1:31 late 23.42° N +13.1 s Sat, Jun 20 1:44 late 23.43° N +13.1 s Sun, Jun 21 1:57 late 23.43° N +13.1 s Mon, Jun 22 2:10 late 23.42° N +13.0 s Tue, Jun 23 2:23 late 23.41° N +12.9 s Wed, Jun 24 2:35 late 23.39° N +12.8 s Thu, Jun 25 2:48 late 23.36° N +12.7 s Fri, Jun 26 3:01 late 23.33° N +12.6 s Sat, Jun 27 3:13 late 23.29° N +12.4 s Sun, Jun 28 3:25 late 23.24° N +12.2 s Mon, Jun 29 3:37 late 23.19° N +12.0 s Tue, Jun 30 3:49 late 23.13° N +11.7 s
July Date Sundial Declination Solar day Wed, Jul 1 4:01 late 23.06° N +11.5 s Thu, Jul 2 4:12 late 22.98° N +11.2 s Fri, Jul 3 4:24 late 22.90° N +10.9 s Sat, Jul 4 4:34 late 22.82° N +10.6 s Sun, Jul 5 4:45 late 22.72° N +10.2 s Mon, Jul 6 4:55 late 22.62° N +9.9 s Tue, Jul 7 5:05 late 22.51° N +9.5 s Wed, Jul 8 5:14 late 22.40° N +9.1 s Thu, Jul 9 5:23 late 22.28° N +8.7 s Fri, Jul 10 5:32 late 22.15° N +8.2 s Sat, Jul 11 5:40 late 22.02° N +7.8 s Sun, Jul 12 5:47 late 21.88° N +7.3 s Mon, Jul 13 5:54 late 21.74° N +6.8 s Tue, Jul 14 6:01 late 21.58° N +6.3 s Wed, Jul 15 6:07 late 21.43° N +5.8 s Thu, Jul 16 6:12 late 21.26° N +5.3 s Fri, Jul 17 6:17 late 21.09° N +4.8 s Sat, Jul 18 6:22 late 20.92° N +4.3 s Sun, Jul 19 6:26 late 20.74° N +3.7 s Mon, Jul 20 6:29 late 20.55° N +3.1 s Tue, Jul 21 6:32 late 20.36° N +2.6 s Wed, Jul 22 6:34 late 20.16° N +2.0 s Thu, Jul 23 6:36 late 19.95° N +1.4 s Fri, Jul 24 6:37 late 19.74° N +0.8 s Sat, Jul 25 6:37 late 19.53° N +0.2 s Sun, Jul 26 6:37 late 19.30° N −0.4 s Mon, Jul 27 6:36 late 19.08° N −1.0 s Tue, Jul 28 6:35 late 18.85° N −1.6 s Wed, Jul 29 6:33 late 18.61° N −2.2 s Thu, Jul 30 6:31 late 18.37° N −2.8 s Fri, Jul 31 6:28 late 18.12° N −3.4 s
August Date Sundial Declination Solar day Sat, Aug 1 6:24 late 17.87° N −4.0 s Sun, Aug 2 6:20 late 17.61° N −4.6 s Mon, Aug 3 6:15 late 17.35° N −5.2 s Tue, Aug 4 6:10 late 17.09° N −5.8 s Wed, Aug 5 6:04 late 16.82° N −6.4 s Thu, Aug 6 5:57 late 16.54° N −7.0 s Fri, Aug 7 5:50 late 16.26° N −7.6 s Sat, Aug 8 5:42 late 15.98° N −8.2 s Sun, Aug 9 5:33 late 15.69° N −8.8 s Mon, Aug 10 5:24 late 15.40° N −9.4 s Tue, Aug 11 5:15 late 15.10° N −9.9 s Wed, Aug 12 5:05 late 14.80° N −10.5 s Thu, Aug 13 4:54 late 14.49° N −11.0 s Fri, Aug 14 4:42 late 14.19° N −11.6 s Sat, Aug 15 4:30 late 13.88° N −12.1 s Sun, Aug 16 4:18 late 13.56° N −12.6 s Mon, Aug 17 4:05 late 13.24° N −13.1 s Tue, Aug 18 3:52 late 12.92° N −13.6 s Wed, Aug 19 3:38 late 12.59° N −14.1 s Thu, Aug 20 3:23 late 12.26° N −14.6 s Fri, Aug 21 3:08 late 11.93° N −15.1 s Sat, Aug 22 2:53 late 11.59° N −15.5 s Sun, Aug 23 2:37 late 11.26° N −16.0 s Mon, Aug 24 2:21 late 10.91° N −16.4 s Tue, Aug 25 2:04 late 10.57° N −16.8 s Wed, Aug 26 1:47 late 10.22° N −17.2 s Thu, Aug 27 1:30 late 9.87° N −17.6 s Fri, Aug 28 1:12 late 9.52° N −17.9 s Sat, Aug 29 0:54 late 9.16° N −18.3 s Sun, Aug 30 0:36 late 8.80° N −18.6 s Mon, Aug 31 0:17 late 8.44° N −18.9 s
September Date Sundial Declination Solar day Tue, Sep 1 0:02 early 8.08° N −19.2 s Wed, Sep 2 0:21 early 7.72° N −19.5 s Thu, Sep 3 0:41 early 7.35° N −19.8 s Fri, Sep 4 1:01 early 6.98° N −20.0 s Sat, Sep 5 1:21 early 6.61° N −20.2 s Sun, Sep 6 1:41 early 6.24° N −20.4 s Mon, Sep 7 2:01 early 5.87° N −20.6 s Tue, Sep 8 2:22 early 5.49° N −20.8 s Wed, Sep 9 2:43 early 5.11° N −21.0 s Thu, Sep 10 3:04 early 4.73° N −21.1 s Fri, Sep 11 3:25 early 4.35° N −21.2 s Sat, Sep 12 3:47 early 3.97° N −21.3 s Sun, Sep 13 4:08 early 3.59° N −21.4 s Mon, Sep 14 4:29 early 3.21° N −21.4 s Tue, Sep 15 4:51 early 2.82° N −21.5 s Wed, Sep 16 5:13 early 2.44° N −21.5 s Thu, Sep 17 5:34 early 2.05° N −21.5 s Fri, Sep 18 5:56 early 1.67° N −21.5 s Sat, Sep 19 6:17 early 1.28° N −21.4 s Sun, Sep 20 6:39 early 0.89° N −21.4 s Mon, Sep 21 7:00 early 0.50° N −21.3 s Tue, Sep 22 7:21 early 0.11° N −21.2 s Wed, Sep 23 7:43 early 0.28° S −21.1 s Thu, Sep 24 8:04 early 0.67° S −20.9 s Fri, Sep 25 8:24 early 1.05° S −20.8 s Sat, Sep 26 8:45 early 1.44° S −20.6 s Sun, Sep 27 9:06 early 1.83° S −20.4 s Mon, Sep 28 9:26 early 2.22° S −20.1 s Tue, Sep 29 9:46 early 2.61° S −19.9 s Wed, Sep 30 10:05 early 3.00° S −19.6 s
October Date Sundial Declination Solar day Thu, Oct 1 10:25 early 3.38° S −19.3 s Fri, Oct 2 10:44 early 3.77° S −19.0 s Sat, Oct 3 11:03 early 4.16° S −18.7 s Sun, Oct 4 11:21 early 4.54° S −18.4 s Mon, Oct 5 11:39 early 4.93° S −18.0 s Tue, Oct 6 11:57 early 5.31° S −17.6 s Wed, Oct 7 12:14 early 5.69° S −17.2 s Thu, Oct 8 12:31 early 6.08° S −16.8 s Fri, Oct 9 12:48 early 6.46° S −16.3 s Sat, Oct 10 13:04 early 6.83° S −15.8 s Sun, Oct 11 13:19 early 7.21° S −15.4 s Mon, Oct 12 13:35 early 7.58° S −14.9 s Tue, Oct 13 13:49 early 7.96° S −14.3 s Wed, Oct 14 14:03 early 8.33° S −13.8 s Thu, Oct 15 14:17 early 8.70° S −13.2 s Fri, Oct 16 14:30 early 9.07° S −12.7 s Sat, Oct 17 14:43 early 9.43° S −12.1 s Sun, Oct 18 14:54 early 9.79° S −11.5 s Mon, Oct 19 15:06 early 10.16° S −10.8 s Tue, Oct 20 15:16 early 10.51° S −10.2 s Wed, Oct 21 15:26 early 10.87° S −9.5 s Thu, Oct 22 15:35 early 11.22° S −8.9 s Fri, Oct 23 15:44 early 11.57° S −8.2 s Sat, Oct 24 15:52 early 11.92° S −7.5 s Sun, Oct 25 15:59 early 12.26° S −6.8 s Mon, Oct 26 16:05 early 12.61° S −6.0 s Tue, Oct 27 16:11 early 12.94° S −5.3 s Wed, Oct 28 16:16 early 13.28° S −4.5 s Thu, Oct 29 16:20 early 13.61° S −3.8 s Fri, Oct 30 16:23 early 13.94° S −3.0 s Sat, Oct 31 16:25 early 14.26° S −2.2 s
November Date Sundial Declination Solar day Sun, Nov 1 16:27 early 14.58° S −1.4 s Mon, Nov 2 16:28 early 14.90° S −0.6 s Tue, Nov 3 16:28 early 15.21° S +0.2 s Wed, Nov 4 16:27 early 15.52° S +1.1 s Thu, Nov 5 16:26 early 15.82° S +1.9 s Fri, Nov 6 16:24 early 16.12° S +2.7 s Sat, Nov 7 16:20 early 16.41° S +3.5 s Sun, Nov 8 16:16 early 16.71° S +4.4 s Mon, Nov 9 16:12 early 16.99° S +5.2 s Tue, Nov 10 16:06 early 17.27° S +6.1 s Wed, Nov 11 16:00 early 17.55° S +6.9 s Thu, Nov 12 15:52 early 17.82° S +7.8 s Fri, Nov 13 15:44 early 18.08° S +8.6 s Sat, Nov 14 15:35 early 18.34° S +9.5 s Sun, Nov 15 15:25 early 18.60° S +10.3 s Mon, Nov 16 15:15 early 18.85° S +11.2 s Tue, Nov 17 15:03 early 19.09° S +12.0 s Wed, Nov 18 14:51 early 19.33° S +12.8 s Thu, Nov 19 14:38 early 19.56° S +13.7 s Fri, Nov 20 14:24 early 19.79° S +14.5 s Sat, Nov 21 14:09 early 20.01° S +15.3 s Sun, Nov 22 13:53 early 20.23° S +16.1 s Mon, Nov 23 13:37 early 20.43° S +16.9 s Tue, Nov 24 13:19 early 20.64° S +17.6 s Wed, Nov 25 13:01 early 20.83° S +18.4 s Thu, Nov 26 12:42 early 21.02° S +19.1 s Fri, Nov 27 12:23 early 21.20° S +19.8 s Sat, Nov 28 12:03 early 21.38° S +20.6 s Sun, Nov 29 11:42 early 21.55° S +21.2 s Mon, Nov 30 11:20 early 21.71° S +21.9 s
December Date Sundial Declination Solar day Tue, Dec 1 10:58 early 21.87° S +22.6 s Wed, Dec 2 10:35 early 22.02° S +23.2 s Thu, Dec 3 10:11 early 22.16° S +23.8 s Fri, Dec 4 9:47 early 22.29° S +24.4 s Sat, Dec 5 9:22 early 22.42° S +24.9 s Sun, Dec 6 8:57 early 22.54° S +25.4 s Mon, Dec 7 8:31 early 22.65° S +25.9 s Tue, Dec 8 8:05 early 22.75° S +26.4 s Wed, Dec 9 7:39 early 22.85° S +26.9 s Thu, Dec 10 7:12 early 22.94° S +27.3 s Fri, Dec 11 6:44 early 23.03° S +27.7 s Sat, Dec 12 6:16 early 23.10° S +28.0 s Sun, Dec 13 5:48 early 23.17° S +28.4 s Mon, Dec 14 5:20 early 23.23° S +28.6 s Tue, Dec 15 4:51 early 23.28° S +28.9 s Wed, Dec 16 4:22 early 23.32° S +29.1 s Thu, Dec 17 3:53 early 23.36° S +29.3 s Fri, Dec 18 3:24 early 23.39° S +29.5 s Sat, Dec 19 2:54 early 23.41° S +29.6 s Sun, Dec 20 2:25 early 23.42° S +29.7 s Mon, Dec 21 1:55 early 23.43° S +29.8 s Tue, Dec 22 1:25 early 23.43° S +29.8 s Wed, Dec 23 0:55 early 23.42° S +29.8 s Thu, Dec 24 0:25 early 23.40° S +29.8 s Fri, Dec 25 0:04 late 23.37° S +29.7 s Sat, Dec 26 0:34 late 23.34° S +29.6 s Sun, Dec 27 1:04 late 23.30° S +29.4 s Mon, Dec 28 1:33 late 23.25° S +29.3 s Tue, Dec 29 2:02 late 23.19° S +29.0 s Wed, Dec 30 2:31 late 23.12° S +28.8 s Thu, Dec 31 3:00 late 23.05° S +28.5 s
Reading the table Sundial is the equation of time: minutes and seconds the Sun stands ahead of the clock (early) or behind it (late) at mean noon. To turn a sundial reading into mean time at your longitude, take an early Sun’s minutes off the reading and add a late Sun’s. Then add four minutes for every degree you are west of your time zone’s meridian (subtract east of it), and an hour in daylight saving time.
The equation of time changes by at most half a minute a day, so a value taken at 12:00 UTC holds anywhere on Earth to within about fifteen seconds. Declination is the Sun’s angle north or south of the celestial equator. Solar day is the time from one solar noon to the next, minus 24 hours; its peaks are Major and MinorLongsol and Shortsol .
Values come from NASA JPL’s DE440 ephemeris, sampled daily and read at 12:00 UTC, to within about 0.15 seconds of the equation of time. Moments are listed on their UTC date. See the methodology , or download every year’s moments from the data page .