Hours of Darkness

No College crew is permitted to be on the water before Lighting Down or after Lighting Up. Crews on the water within 15 minutes of lighting up or lighting down must have static white lights (clearly visible) attached to both the bow and stern of the boat.

Lighting Up and Down times for 2021 are listed in the table below. All of the times are adjusted to BST where applicable. The lighting times for today and tomorrow are available on a WAP phone (http://m.cucbc.org/lighting).

Lighting down is defined as the time when the sun rises to 95° below the zenith, whilst lighting up is the time at which the sun sets to 94° below the zenith.

DayDateLighting DownLighting Up
Monday18/01/202107:2616:47
Tuesday19/01/202107:2516:48
Wednesday20/01/202107:2416:50
Thursday21/01/202107:2316:52
Friday22/01/202107:2216:53
Saturday23/01/202107:2116:55
Sunday24/01/202107:2016:57
Monday25/01/202107:1916:58
Tuesday26/01/202107:1817:00
Wednesday27/01/202107:1617:02
Thursday28/01/202107:1517:04
Friday29/01/202107:1417:05
Saturday30/01/202107:1217:07
Sunday31/01/202107:1117:09
Monday01/02/202107:0917:11
Tuesday02/02/202107:0817:12
Wednesday03/02/202107:0617:14
Thursday04/02/202107:0517:16
Friday05/02/202107:0317:18
Saturday06/02/202107:0117:20
Sunday07/02/202107:0017:21
Monday08/02/202106:5817:23
Tuesday09/02/202106:5617:25
Wednesday10/02/202106:5417:27
Thursday11/02/202106:5317:29
Friday12/02/202106:5117:30
Saturday13/02/202106:4917:32
Sunday14/02/202106:4717:34
Monday15/02/202106:4517:36
Tuesday16/02/202106:4317:38
Wednesday17/02/202106:4117:39
Thursday18/02/202106:3917:41
Friday19/02/202106:3817:43
Saturday20/02/202106:3617:45
Sunday21/02/202106:3317:47
Monday22/02/202106:3117:49
Tuesday23/02/202106:2917:50
Wednesday24/02/202106:2717:52
Thursday25/02/202106:2517:54
Friday26/02/202106:2317:56
Saturday27/02/202106:2117:57
Sunday28/02/202106:1917:59
Monday01/03/202106:1718:01
Tuesday02/03/202106:1418:03
Wednesday03/03/202106:1218:05
Thursday04/03/202106:1018:06
Friday05/03/202106:0818:08
Saturday06/03/202106:0618:10
Sunday07/03/202106:0318:12
Monday08/03/202106:0118:13
Tuesday09/03/202105:5918:15
Wednesday10/03/202105:5718:17
Thursday11/03/202105:5418:19
Friday12/03/202105:5218:21
Saturday13/03/202105:5018:22
Sunday14/03/202105:4718:24
Monday15/03/202105:4518:26
Tuesday16/03/202105:4318:28
Wednesday17/03/202105:4018:29
Thursday18/03/202105:3818:31
Friday19/03/202105:3618:33
Saturday20/03/202105:3318:35
Sunday21/03/202105:3118:36
Monday22/03/202105:2918:38
Tuesday23/03/202105:2618:40
Wednesday24/03/202105:2418:42
Thursday25/03/202105:2218:43
Friday26/03/202105:1918:45
Saturday27/03/202105:1718:47
Sunday28/03/202106:1419:49
Monday29/03/202106:1219:50
Tuesday30/03/202106:1019:52
Wednesday31/03/202106:0719:54
Thursday01/04/202106:0519:56
Friday02/04/202106:0319:58
Saturday03/04/202106:0019:59
Sunday04/04/202105:5820:01
Monday05/04/202105:5520:03
Tuesday06/04/202105:5320:05
Wednesday07/04/202105:5120:06
Thursday08/04/202105:4820:08
Friday09/04/202105:4620:10
Saturday10/04/202105:4420:12
Sunday11/04/202105:4120:14
Monday12/04/202105:3920:15
Tuesday13/04/202105:3720:17
Wednesday14/04/202105:3420:19
Thursday15/04/202105:3220:21
Friday16/04/202105:3020:23
Saturday17/04/202105:2720:24
Sunday18/04/202105:2520:26
Monday19/04/202105:2320:28
Tuesday20/04/202105:2120:30
Wednesday21/04/202105:1820:32
Thursday22/04/202105:1620:34
Friday23/04/202105:1420:35
Saturday24/04/202105:1220:37
Sunday25/04/202105:0920:39
Monday26/04/202105:0720:41
Tuesday27/04/202105:0520:43
Wednesday28/04/202105:0320:45
Thursday29/04/202105:0120:46
Friday30/04/202104:5920:48
Saturday01/05/202104:5720:50
Sunday02/05/202104:5420:52
Monday03/05/202104:5220:54
Tuesday04/05/202104:5020:55
Wednesday05/05/202104:4820:57
Thursday06/05/202104:4620:59
Friday07/05/202104:4421:01
Saturday08/05/202104:4321:03
Sunday09/05/202104:4121:04
Monday10/05/202104:3921:06
Tuesday11/05/202104:3721:08
Wednesday12/05/202104:3521:10
Thursday13/05/202104:3321:11
Friday14/05/202104:3121:13
Saturday15/05/202104:3021:15
Sunday16/05/202104:2821:16
Monday17/05/202104:2621:18
Tuesday18/05/202104:2521:20
Wednesday19/05/202104:2321:21
Thursday20/05/202104:2221:23
Friday21/05/202104:2021:24
Saturday22/05/202104:1921:26
Sunday23/05/202104:1721:27
Monday24/05/202104:1621:29
Tuesday25/05/202104:1521:30
Wednesday26/05/202104:1321:32
Thursday27/05/202104:1221:33
Friday28/05/202104:1121:35
Saturday29/05/202104:1021:36
Sunday30/05/202104:0921:37
Monday31/05/202104:0821:39
Tuesday01/06/202104:0721:40
Wednesday02/06/202104:0621:41
Thursday03/06/202104:0521:42
Friday04/06/202104:0421:43
Saturday05/06/202104:0321:44
Sunday06/06/202104:0221:45
Monday07/06/202104:0221:46
Tuesday08/06/202104:0121:47
Wednesday09/06/202104:0121:48
Thursday10/06/202104:0021:49
Friday11/06/202104:0021:49
Saturday12/06/202103:5921:50
Sunday13/06/202103:5921:51
Monday14/06/202103:5921:51
Tuesday15/06/202103:5921:52
Wednesday16/06/202103:5921:52
Thursday17/06/202103:5921:53
Friday18/06/202103:5921:53
Saturday19/06/202103:5921:53
Sunday20/06/202103:5921:54
Monday21/06/202103:5921:54
Tuesday22/06/202103:5921:54
Wednesday23/06/202104:0021:54
Thursday24/06/202104:0021:54
Friday25/06/202104:0121:54
Saturday26/06/202104:0121:54
Sunday27/06/202104:0221:54
Monday28/06/202104:0221:53
Tuesday29/06/202104:0321:53
Wednesday30/06/202104:0421:53
Thursday01/07/202104:0521:52
Friday02/07/202104:0521:52
Saturday03/07/202104:0621:51
Sunday04/07/202104:0721:51
Monday05/07/202104:0821:50
Tuesday06/07/202104:0921:49
Wednesday07/07/202104:1021:48
Thursday08/07/202104:1221:48
Friday09/07/202104:1321:47
Saturday10/07/202104:1421:46
Sunday11/07/202104:1521:45
Monday12/07/202104:1721:44
Tuesday13/07/202104:1821:43
Wednesday14/07/202104:1921:41
Thursday15/07/202104:2121:40
Friday16/07/202104:2221:39
Saturday17/07/202104:2421:38
Sunday18/07/202104:2521:36
Monday19/07/202104:2721:35
Tuesday20/07/202104:2821:34
Wednesday21/07/202104:3021:32
Thursday22/07/202104:3121:31
Friday23/07/202104:3321:29
Saturday24/07/202104:3521:28
Sunday25/07/202104:3621:26
Monday26/07/202104:3821:24
Tuesday27/07/202104:4021:23
Wednesday28/07/202104:4121:21
Thursday29/07/202104:4321:19
Friday30/07/202104:4521:17
Saturday31/07/202104:4721:16
Sunday01/08/202104:4821:14
Monday02/08/202104:5021:12
Tuesday03/08/202104:5221:10
Wednesday04/08/202104:5421:08
Thursday05/08/202104:5521:06
Friday06/08/202104:5721:04
Saturday07/08/202104:5921:02
Sunday08/08/202105:0121:00
Monday09/08/202105:0320:58
Tuesday10/08/202105:0420:56
Wednesday11/08/202105:0620:54
Thursday12/08/202105:0820:52
Friday13/08/202105:1020:50
Saturday14/08/202105:1220:48
Sunday15/08/202105:1320:46
Monday16/08/202105:1520:43
Tuesday17/08/202105:1720:41
Wednesday18/08/202105:1920:39
Thursday19/08/202105:2020:37
Friday20/08/202105:2220:35
Saturday21/08/202105:2420:32
Sunday22/08/202105:2620:30
Monday23/08/202105:2820:28
Tuesday24/08/202105:2920:26
Wednesday25/08/202105:3120:23
Thursday26/08/202105:3320:21
Friday27/08/202105:3520:19
Saturday28/08/202105:3620:16
Sunday29/08/202105:3820:14
Monday30/08/202105:4020:12
Tuesday31/08/202105:4220:09
Wednesday01/09/202105:4320:07
Thursday02/09/202105:4520:05
Friday03/09/202105:4720:02
Saturday04/09/202105:4920:00
Sunday05/09/202105:5019:58
Monday06/09/202105:5219:55
Tuesday07/09/202105:5419:53
Wednesday08/09/202105:5519:50
Thursday09/09/202105:5719:48
Friday10/09/202105:5919:46
Saturday11/09/202106:0119:43
Sunday12/09/202106:0219:41
Monday13/09/202106:0419:38
Tuesday14/09/202106:0619:36
Wednesday15/09/202106:0719:34
Thursday16/09/202106:0919:31
Friday17/09/202106:1119:29
Saturday18/09/202106:1219:27
Sunday19/09/202106:1419:24
Monday20/09/202106:1619:22
Tuesday21/09/202106:1719:19
Wednesday22/09/202106:1919:17
Thursday23/09/202106:2119:15
Friday24/09/202106:2319:12
Saturday25/09/202106:2419:10
Sunday26/09/202106:2619:08
Monday27/09/202106:2819:05
Tuesday28/09/202106:2919:03
Wednesday29/09/202106:3119:01
Thursday30/09/202106:3318:58
Friday01/10/202106:3418:56
Saturday02/10/202106:3618:54
Sunday03/10/202106:3818:51
Monday04/10/202106:3918:49
Tuesday05/10/202106:4118:47
Wednesday06/10/202106:4318:45
Thursday07/10/202106:4418:42
Friday08/10/202106:4618:40
Saturday09/10/202106:4818:38
Sunday10/10/202106:4918:36
Monday11/10/202106:5118:33
Tuesday12/10/202106:5318:31
Wednesday13/10/202106:5418:29
Thursday14/10/202106:5618:27
Friday15/10/202106:5818:25
Saturday16/10/202107:0018:23
Sunday17/10/202107:0118:21
Monday18/10/202107:0318:18
Tuesday19/10/202107:0518:16
Wednesday20/10/202107:0618:14
Thursday21/10/202107:0818:12
Friday22/10/202107:1018:10
Saturday23/10/202107:1218:08
Sunday24/10/202107:1318:06
Monday25/10/202107:1518:04
Tuesday26/10/202107:1718:02
Wednesday27/10/202107:1818:01
Thursday28/10/202107:2017:59
Friday29/10/202107:2217:57
Saturday30/10/202107:2417:55
Sunday31/10/202106:2516:53
Monday01/11/202106:2716:51
Tuesday02/11/202106:2916:50
Wednesday03/11/202106:3016:48
Thursday04/11/202106:3216:46
Friday05/11/202106:3416:45
Saturday06/11/202106:3616:43
Sunday07/11/202106:3716:41
Monday08/11/202106:3916:40
Tuesday09/11/202106:4116:38
Wednesday10/11/202106:4216:37
Thursday11/11/202106:4416:35
Friday12/11/202106:4616:34
Saturday13/11/202106:4716:33
Sunday14/11/202106:4916:31
Monday15/11/202106:5116:30
Tuesday16/11/202106:5216:29
Wednesday17/11/202106:5416:27
Thursday18/11/202106:5516:26
Friday19/11/202106:5716:25
Saturday20/11/202106:5916:24
Sunday21/11/202107:0016:23
Monday22/11/202107:0216:22
Tuesday23/11/202107:0316:21
Wednesday24/11/202107:0516:20
Thursday25/11/202107:0616:19
Friday26/11/202107:0816:18
Saturday27/11/202107:0916:18
Sunday28/11/202107:1016:17
Monday29/11/202107:1216:16
Tuesday30/11/202107:1316:16
Wednesday01/12/202107:1416:15
Thursday02/12/202107:1616:15
Friday03/12/202107:1716:14
Saturday04/12/202107:1816:14
Sunday05/12/202107:1916:13
Monday06/12/202107:2116:13
Tuesday07/12/202107:2216:13
Wednesday08/12/202107:2316:13
Thursday09/12/202107:2416:12
Friday10/12/202107:2516:12
Saturday11/12/202107:2616:12
Sunday12/12/202107:2716:12
Monday13/12/202107:2816:12
Tuesday14/12/202107:2916:12
Wednesday15/12/202107:2916:13
Thursday16/12/202107:3016:13
Friday17/12/202107:3116:13
Saturday18/12/202107:3116:14
Sunday19/12/202107:3216:14
Monday20/12/202107:3316:14
Tuesday21/12/202107:3316:15
Wednesday22/12/202107:3416:15
Thursday23/12/202107:3416:16
Friday24/12/202107:3416:17
Saturday25/12/202107:3516:17
Sunday26/12/202107:3516:18
Monday27/12/202107:3516:19
Tuesday28/12/202107:3516:20
Wednesday29/12/202107:3516:21
Thursday30/12/202107:3516:22
Friday31/12/202107:3516:23

XML and CSV files of the hours of darkness for the current year are available. Other webmasters may wish to use these to display the lighting up and down times on their own websites.

» XML Data for 2021
» CSV Data for 2021

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