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 2026 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
Tuesday06/01/202607:3416:29
Wednesday07/01/202607:3416:31
Thursday08/01/202607:3416:32
Friday09/01/202607:3316:33
Saturday10/01/202607:3316:35
Sunday11/01/202607:3216:36
Monday12/01/202607:3116:37
Tuesday13/01/202607:3116:39
Wednesday14/01/202607:3016:40
Thursday15/01/202607:2916:42
Friday16/01/202607:2816:43
Saturday17/01/202607:2816:45
Sunday18/01/202607:2716:47
Monday19/01/202607:2616:48
Tuesday20/01/202607:2516:50
Wednesday21/01/202607:2416:51
Thursday22/01/202607:2316:53
Friday23/01/202607:2116:55
Saturday24/01/202607:2016:56
Sunday25/01/202607:1916:58
Monday26/01/202607:1817:00
Tuesday27/01/202607:1717:02
Wednesday28/01/202607:1517:03
Thursday29/01/202607:1417:05
Friday30/01/202607:1217:07
Saturday31/01/202607:1117:09
Sunday01/02/202607:1017:10
Monday02/02/202607:0817:12
Tuesday03/02/202607:0617:14
Wednesday04/02/202607:0517:16
Thursday05/02/202607:0317:17
Friday06/02/202607:0217:19
Saturday07/02/202607:0017:21
Sunday08/02/202606:5817:23
Monday09/02/202606:5717:25
Tuesday10/02/202606:5517:26
Wednesday11/02/202606:5317:28
Thursday12/02/202606:5117:30
Friday13/02/202606:4917:32
Saturday14/02/202606:4817:34
Sunday15/02/202606:4617:35
Monday16/02/202606:4417:37
Tuesday17/02/202606:4217:39
Wednesday18/02/202606:4017:41
Thursday19/02/202606:3817:43
Friday20/02/202606:3617:45
Saturday21/02/202606:3417:46
Sunday22/02/202606:3217:48
Monday23/02/202606:3017:50
Tuesday24/02/202606:2817:52
Wednesday25/02/202606:2617:54
Thursday26/02/202606:2417:55
Friday27/02/202606:2117:57
Saturday28/02/202606:1917:59
Sunday01/03/202606:1718:01
Monday02/03/202606:1518:02
Tuesday03/03/202606:1318:04
Wednesday04/03/202606:1118:06
Thursday05/03/202606:0818:08
Friday06/03/202606:0618:10
Saturday07/03/202606:0418:11
Sunday08/03/202606:0218:13
Monday09/03/202605:5918:15
Tuesday10/03/202605:5718:17
Wednesday11/03/202605:5518:18
Thursday12/03/202605:5318:20
Friday13/03/202605:5018:22
Saturday14/03/202605:4818:24
Sunday15/03/202605:4618:25
Monday16/03/202605:4318:27
Tuesday17/03/202605:4118:29
Wednesday18/03/202605:3918:31
Thursday19/03/202605:3618:32
Friday20/03/202605:3418:34
Saturday21/03/202605:3218:36
Sunday22/03/202605:2918:38
Monday23/03/202605:2718:39
Tuesday24/03/202605:2418:41
Wednesday25/03/202605:2218:43
Thursday26/03/202605:2018:45
Friday27/03/202605:1718:47
Saturday28/03/202605:1518:48
Sunday29/03/202606:1319:50
Monday30/03/202606:1019:52
Tuesday31/03/202606:0819:54
Wednesday01/04/202606:0519:55
Thursday02/04/202606:0319:57
Friday03/04/202606:0119:59
Saturday04/04/202605:5820:01
Sunday05/04/202605:5620:03
Monday06/04/202605:5420:04
Tuesday07/04/202605:5120:06
Wednesday08/04/202605:4920:08
Thursday09/04/202605:4720:10
Friday10/04/202605:4420:11
Saturday11/04/202605:4220:13
Sunday12/04/202605:3920:15
Monday13/04/202605:3720:17
Tuesday14/04/202605:3520:19
Wednesday15/04/202605:3220:20
Thursday16/04/202605:3020:22
Friday17/04/202605:2820:24
Saturday18/04/202605:2620:26
Sunday19/04/202605:2320:28
Monday20/04/202605:2120:30
Tuesday21/04/202605:1920:31
Wednesday22/04/202605:1720:33
Thursday23/04/202605:1420:35
Friday24/04/202605:1220:37
Saturday25/04/202605:1020:39
Sunday26/04/202605:0820:40
Monday27/04/202605:0620:42
Tuesday28/04/202605:0320:44
Wednesday29/04/202605:0120:46
Thursday30/04/202604:5920:48
Friday01/05/202604:5720:50
Saturday02/05/202604:5520:51
Sunday03/05/202604:5320:53
Monday04/05/202604:5120:55
Tuesday05/05/202604:4920:57
Wednesday06/05/202604:4720:59
Thursday07/05/202604:4521:00
Friday08/05/202604:4321:02
Saturday09/05/202604:4121:04
Sunday10/05/202604:3921:06
Monday11/05/202604:3721:07
Tuesday12/05/202604:3521:09
Wednesday13/05/202604:3421:11
Thursday14/05/202604:3221:13
Friday15/05/202604:3021:14
Saturday16/05/202604:2821:16
Sunday17/05/202604:2721:18
Monday18/05/202604:2521:19
Tuesday19/05/202604:2421:21
Wednesday20/05/202604:2221:22
Thursday21/05/202604:2021:24
Friday22/05/202604:1921:26
Saturday23/05/202604:1821:27
Sunday24/05/202604:1621:29
Monday25/05/202604:1521:30
Tuesday26/05/202604:1421:32
Wednesday27/05/202604:1221:33
Thursday28/05/202604:1121:34
Friday29/05/202604:1021:36
Saturday30/05/202604:0921:37
Sunday31/05/202604:0821:38
Monday01/06/202604:0721:39
Tuesday02/06/202604:0621:41
Wednesday03/06/202604:0521:42
Thursday04/06/202604:0421:43
Friday05/06/202604:0321:44
Saturday06/06/202604:0321:45
Sunday07/06/202604:0221:46
Monday08/06/202604:0121:47
Tuesday09/06/202604:0121:48
Wednesday10/06/202604:0021:49
Thursday11/06/202604:0021:49
Friday12/06/202603:5921:50
Saturday13/06/202603:5921:51
Sunday14/06/202603:5921:51
Monday15/06/202603:5921:52
Tuesday16/06/202603:5921:52
Wednesday17/06/202603:5921:53
Thursday18/06/202603:5921:53
Friday19/06/202603:5921:53
Saturday20/06/202603:5921:54
Sunday21/06/202603:5921:54
Monday22/06/202603:5921:54
Tuesday23/06/202604:0021:54
Wednesday24/06/202604:0021:54
Thursday25/06/202604:0021:54
Friday26/06/202604:0121:54
Saturday27/06/202604:0221:54
Sunday28/06/202604:0221:53
Monday29/06/202604:0321:53
Tuesday30/06/202604:0421:53
Wednesday01/07/202604:0421:52
Thursday02/07/202604:0521:52
Friday03/07/202604:0621:51
Saturday04/07/202604:0721:51
Sunday05/07/202604:0821:50
Monday06/07/202604:0921:49
Tuesday07/07/202604:1021:49
Wednesday08/07/202604:1121:48
Thursday09/07/202604:1321:47
Friday10/07/202604:1421:46
Saturday11/07/202604:1521:45
Sunday12/07/202604:1621:44
Monday13/07/202604:1821:43
Tuesday14/07/202604:1921:42
Wednesday15/07/202604:2021:41
Thursday16/07/202604:2221:39
Friday17/07/202604:2321:38
Saturday18/07/202604:2521:37
Sunday19/07/202604:2621:35
Monday20/07/202604:2821:34
Tuesday21/07/202604:2921:33
Wednesday22/07/202604:3121:31
Thursday23/07/202604:3321:30
Friday24/07/202604:3421:28
Saturday25/07/202604:3621:26
Sunday26/07/202604:3821:25
Monday27/07/202604:3921:23
Tuesday28/07/202604:4121:21
Wednesday29/07/202604:4321:20
Thursday30/07/202604:4421:18
Friday31/07/202604:4621:16
Saturday01/08/202604:4821:14
Sunday02/08/202604:5021:12
Monday03/08/202604:5121:10
Tuesday04/08/202604:5321:09
Wednesday05/08/202604:5521:07
Thursday06/08/202604:5721:05
Friday07/08/202604:5921:03
Saturday08/08/202605:0021:01
Sunday09/08/202605:0220:59
Monday10/08/202605:0420:57
Tuesday11/08/202605:0620:55
Wednesday12/08/202605:0820:52
Thursday13/08/202605:0920:50
Friday14/08/202605:1120:48
Saturday15/08/202605:1320:46
Sunday16/08/202605:1520:44
Monday17/08/202605:1720:42
Tuesday18/08/202605:1820:39
Wednesday19/08/202605:2020:37
Thursday20/08/202605:2220:35
Friday21/08/202605:2420:33
Saturday22/08/202605:2520:31
Sunday23/08/202605:2720:28
Monday24/08/202605:2920:26
Tuesday25/08/202605:3120:24
Wednesday26/08/202605:3320:21
Thursday27/08/202605:3420:19
Friday28/08/202605:3620:17
Saturday29/08/202605:3820:14
Sunday30/08/202605:4020:12
Monday31/08/202605:4120:10
Tuesday01/09/202605:4320:07
Wednesday02/09/202605:4520:05
Thursday03/09/202605:4620:03
Friday04/09/202605:4820:00
Saturday05/09/202605:5019:58
Sunday06/09/202605:5219:56
Monday07/09/202605:5319:53
Tuesday08/09/202605:5519:51
Wednesday09/09/202605:5719:49
Thursday10/09/202605:5919:46
Friday11/09/202606:0019:44
Saturday12/09/202606:0219:41
Sunday13/09/202606:0419:39
Monday14/09/202606:0519:37
Tuesday15/09/202606:0719:34
Wednesday16/09/202606:0919:32
Thursday17/09/202606:1019:29
Friday18/09/202606:1219:27
Saturday19/09/202606:1419:25
Sunday20/09/202606:1519:22
Monday21/09/202606:1719:20
Tuesday22/09/202606:1919:18
Wednesday23/09/202606:2019:15
Thursday24/09/202606:2219:13
Friday25/09/202606:2419:10
Saturday26/09/202606:2619:08
Sunday27/09/202606:2719:06
Monday28/09/202606:2919:03
Tuesday29/09/202606:3119:01
Wednesday30/09/202606:3218:59
Thursday01/10/202606:3418:56
Friday02/10/202606:3618:54
Saturday03/10/202606:3718:52
Sunday04/10/202606:3918:50
Monday05/10/202606:4118:47
Tuesday06/10/202606:4218:45
Wednesday07/10/202606:4418:43
Thursday08/10/202606:4618:41
Friday09/10/202606:4718:38
Saturday10/10/202606:4918:36
Sunday11/10/202606:5118:34
Monday12/10/202606:5218:32
Tuesday13/10/202606:5418:30
Wednesday14/10/202606:5618:27
Thursday15/10/202606:5818:25
Friday16/10/202606:5918:23
Saturday17/10/202607:0118:21
Sunday18/10/202607:0318:19
Monday19/10/202607:0418:17
Tuesday20/10/202607:0618:15
Wednesday21/10/202607:0818:13
Thursday22/10/202607:0918:11
Friday23/10/202607:1118:09
Saturday24/10/202607:1318:07
Sunday25/10/202606:1517:05
Monday26/10/202606:1617:03
Tuesday27/10/202606:1817:01
Wednesday28/10/202606:2016:59
Thursday29/10/202606:2116:57
Friday30/10/202606:2316:55
Saturday31/10/202606:2516:54
Sunday01/11/202606:2716:52
Monday02/11/202606:2816:50
Tuesday03/11/202606:3016:48
Wednesday04/11/202606:3216:47
Thursday05/11/202606:3316:45
Friday06/11/202606:3516:43
Saturday07/11/202606:3716:42
Sunday08/11/202606:3916:40
Monday09/11/202606:4016:39
Tuesday10/11/202606:4216:37
Wednesday11/11/202606:4416:36
Thursday12/11/202606:4516:34
Friday13/11/202606:4716:33
Saturday14/11/202606:4916:32
Sunday15/11/202606:5016:30
Monday16/11/202606:5216:29
Tuesday17/11/202606:5316:28
Wednesday18/11/202606:5516:27
Thursday19/11/202606:5716:25
Friday20/11/202606:5816:24
Saturday21/11/202607:0016:23
Sunday22/11/202607:0116:22
Monday23/11/202607:0316:21
Tuesday24/11/202607:0416:20
Wednesday25/11/202607:0616:19
Thursday26/11/202607:0716:19
Friday27/11/202607:0916:18
Saturday28/11/202607:1016:17
Sunday29/11/202607:1216:16
Monday30/11/202607:1316:16
Tuesday01/12/202607:1416:15
Wednesday02/12/202607:1516:15
Thursday03/12/202607:1716:14
Friday04/12/202607:1816:14
Saturday05/12/202607:1916:13
Sunday06/12/202607:2016:13
Monday07/12/202607:2216:13
Tuesday08/12/202607:2316:13
Wednesday09/12/202607:2416:12
Thursday10/12/202607:2516:12
Friday11/12/202607:2616:12
Saturday12/12/202607:2716:12
Sunday13/12/202607:2716:12
Monday14/12/202607:2816:12
Tuesday15/12/202607:2916:13
Wednesday16/12/202607:3016:13
Thursday17/12/202607:3116:13
Friday18/12/202607:3116:13
Saturday19/12/202607:3216:14
Sunday20/12/202607:3216:14
Monday21/12/202607:3316:15
Tuesday22/12/202607:3316:15
Wednesday23/12/202607:3416:16
Thursday24/12/202607:3416:16
Friday25/12/202607:3516:17
Saturday26/12/202607:3516:18
Sunday27/12/202607:3516:19
Monday28/12/202607:3516:20
Tuesday29/12/202607:3516:20
Wednesday30/12/202607:3516:21
Thursday31/12/202607:3516:22

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 2026
» CSV Data for 2026

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