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 2023 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
Thursday02/02/202307:0817:12
Friday03/02/202307:0717:13
Saturday04/02/202307:0517:15
Sunday05/02/202307:0417:17
Monday06/02/202307:0217:19
Tuesday07/02/202307:0017:21
Wednesday08/02/202306:5917:22
Thursday09/02/202306:5717:24
Friday10/02/202306:5517:26
Saturday11/02/202306:5417:28
Sunday12/02/202306:5217:30
Monday13/02/202306:5017:31
Tuesday14/02/202306:4817:33
Wednesday15/02/202306:4617:35
Thursday16/02/202306:4417:37
Friday17/02/202306:4217:39
Saturday18/02/202306:4017:40
Sunday19/02/202306:3817:42
Monday20/02/202306:3617:44
Tuesday21/02/202306:3417:46
Wednesday22/02/202306:3217:48
Thursday23/02/202306:3017:49
Friday24/02/202306:2817:51
Saturday25/02/202306:2617:53
Sunday26/02/202306:2417:55
Monday27/02/202306:2217:57
Tuesday28/02/202306:2017:58
Wednesday01/03/202306:1818:00
Thursday02/03/202306:1618:02
Friday03/03/202306:1318:04
Saturday04/03/202306:1118:06
Sunday05/03/202306:0918:07
Monday06/03/202306:0718:09
Tuesday07/03/202306:0418:11
Wednesday08/03/202306:0218:13
Thursday09/03/202306:0018:14
Friday10/03/202305:5818:16
Saturday11/03/202305:5518:18
Sunday12/03/202305:5318:20
Monday13/03/202305:5118:21
Tuesday14/03/202305:4918:23
Wednesday15/03/202305:4618:25
Thursday16/03/202305:4418:27
Friday17/03/202305:4218:28
Saturday18/03/202305:3918:30
Sunday19/03/202305:3718:32
Monday20/03/202305:3518:34
Tuesday21/03/202305:3218:35
Wednesday22/03/202305:3018:37
Thursday23/03/202305:2718:39
Friday24/03/202305:2518:41
Saturday25/03/202305:2318:43
Sunday26/03/202306:2019:44
Monday27/03/202306:1819:46
Tuesday28/03/202306:1619:48
Wednesday29/03/202306:1319:50
Thursday30/03/202306:1119:51
Friday31/03/202306:0819:53
Saturday01/04/202306:0619:55
Sunday02/04/202306:0419:57
Monday03/04/202306:0119:58
Tuesday04/04/202305:5920:00
Wednesday05/04/202305:5720:02
Thursday06/04/202305:5420:04
Friday07/04/202305:5220:06
Saturday08/04/202305:5020:07
Sunday09/04/202305:4720:09
Monday10/04/202305:4520:11
Tuesday11/04/202305:4220:13
Wednesday12/04/202305:4020:15
Thursday13/04/202305:3820:16
Friday14/04/202305:3520:18
Saturday15/04/202305:3320:20
Sunday16/04/202305:3120:22
Monday17/04/202305:2920:24
Tuesday18/04/202305:2620:25
Wednesday19/04/202305:2420:27
Thursday20/04/202305:2220:29
Friday21/04/202305:1920:31
Saturday22/04/202305:1720:33
Sunday23/04/202305:1520:35
Monday24/04/202305:1320:36
Tuesday25/04/202305:1020:38
Wednesday26/04/202305:0820:40
Thursday27/04/202305:0620:42
Friday28/04/202305:0420:44
Saturday29/04/202305:0220:45
Sunday30/04/202305:0020:47
Monday01/05/202304:5820:49
Tuesday02/05/202304:5520:51
Wednesday03/05/202304:5320:53
Thursday04/05/202304:5120:55
Friday05/05/202304:4920:56
Saturday06/05/202304:4720:58
Sunday07/05/202304:4521:00
Monday08/05/202304:4321:02
Tuesday09/05/202304:4221:03
Wednesday10/05/202304:4021:05
Thursday11/05/202304:3821:07
Friday12/05/202304:3621:09
Saturday13/05/202304:3421:10
Sunday14/05/202304:3221:12
Monday15/05/202304:3121:14
Tuesday16/05/202304:2921:15
Wednesday17/05/202304:2721:17
Thursday18/05/202304:2621:19
Friday19/05/202304:2421:20
Saturday20/05/202304:2221:22
Sunday21/05/202304:2121:24
Monday22/05/202304:1921:25
Tuesday23/05/202304:1821:27
Wednesday24/05/202304:1721:28
Thursday25/05/202304:1521:30
Friday26/05/202304:1421:31
Saturday27/05/202304:1321:33
Sunday28/05/202304:1121:34
Monday29/05/202304:1021:35
Tuesday30/05/202304:0921:37
Wednesday31/05/202304:0821:38
Thursday01/06/202304:0721:39
Friday02/06/202304:0621:40
Saturday03/06/202304:0521:42
Sunday04/06/202304:0421:43
Monday05/06/202304:0321:44
Tuesday06/06/202304:0321:45
Wednesday07/06/202304:0221:46
Thursday08/06/202304:0121:47
Friday09/06/202304:0121:48
Saturday10/06/202304:0021:48
Sunday11/06/202304:0021:49
Monday12/06/202304:0021:50
Tuesday13/06/202303:5921:50
Wednesday14/06/202303:5921:51
Thursday15/06/202303:5921:52
Friday16/06/202303:5921:52
Saturday17/06/202303:5921:53
Sunday18/06/202303:5921:53
Monday19/06/202303:5921:53
Tuesday20/06/202303:5921:54
Wednesday21/06/202303:5921:54
Thursday22/06/202303:5921:54
Friday23/06/202304:0021:54
Saturday24/06/202304:0021:54
Sunday25/06/202304:0021:54
Monday26/06/202304:0121:54
Tuesday27/06/202304:0121:54
Wednesday28/06/202304:0221:53
Thursday29/06/202304:0321:53
Friday30/06/202304:0321:53
Saturday01/07/202304:0421:52
Sunday02/07/202304:0521:52
Monday03/07/202304:0621:51
Tuesday04/07/202304:0721:51
Wednesday05/07/202304:0821:50
Thursday06/07/202304:0921:50
Friday07/07/202304:1021:49
Saturday08/07/202304:1121:48
Sunday09/07/202304:1221:47
Monday10/07/202304:1321:46
Tuesday11/07/202304:1521:45
Wednesday12/07/202304:1621:44
Thursday13/07/202304:1721:43
Friday14/07/202304:1921:42
Saturday15/07/202304:2021:41
Sunday16/07/202304:2121:40
Monday17/07/202304:2321:38
Tuesday18/07/202304:2421:37
Wednesday19/07/202304:2621:36
Thursday20/07/202304:2721:34
Friday21/07/202304:2921:33
Saturday22/07/202304:3121:31
Sunday23/07/202304:3221:30
Monday24/07/202304:3421:28
Tuesday25/07/202304:3621:27
Wednesday26/07/202304:3721:25
Thursday27/07/202304:3921:24
Friday28/07/202304:4121:22
Saturday29/07/202304:4221:20
Sunday30/07/202304:4421:18
Monday31/07/202304:4621:17
Tuesday01/08/202304:4721:15
Wednesday02/08/202304:4921:13
Thursday03/08/202304:5121:11
Friday04/08/202304:5321:09
Saturday05/08/202304:5521:07
Sunday06/08/202304:5621:05
Monday07/08/202304:5821:03
Tuesday08/08/202305:0021:01
Wednesday09/08/202305:0220:59
Thursday10/08/202305:0320:57
Friday11/08/202305:0520:55
Saturday12/08/202305:0720:53
Sunday13/08/202305:0920:51
Monday14/08/202305:1120:49
Tuesday15/08/202305:1220:47
Wednesday16/08/202305:1420:44
Thursday17/08/202305:1620:42
Friday18/08/202305:1820:40
Saturday19/08/202305:2020:38
Sunday20/08/202305:2120:36
Monday21/08/202305:2320:33
Tuesday22/08/202305:2520:31
Wednesday23/08/202305:2720:29
Thursday24/08/202305:2820:27
Friday25/08/202305:3020:24
Saturday26/08/202305:3220:22
Sunday27/08/202305:3420:20
Monday28/08/202305:3620:17
Tuesday29/08/202305:3720:15
Wednesday30/08/202305:3920:13
Thursday31/08/202305:4120:10
Friday01/09/202305:4320:08
Saturday02/09/202305:4420:06
Sunday03/09/202305:4620:03
Monday04/09/202305:4820:01
Tuesday05/09/202305:4919:59
Wednesday06/09/202305:5119:56
Thursday07/09/202305:5319:54
Friday08/09/202305:5519:52
Saturday09/09/202305:5619:49
Sunday10/09/202305:5819:47
Monday11/09/202306:0019:44
Tuesday12/09/202306:0119:42
Wednesday13/09/202306:0319:40
Thursday14/09/202306:0519:37
Friday15/09/202306:0719:35
Saturday16/09/202306:0819:32
Sunday17/09/202306:1019:30
Monday18/09/202306:1219:28
Tuesday19/09/202306:1319:25
Wednesday20/09/202306:1519:23
Thursday21/09/202306:1719:21
Friday22/09/202306:1819:18
Saturday23/09/202306:2019:16
Sunday24/09/202306:2219:13
Monday25/09/202306:2319:11
Tuesday26/09/202306:2519:09
Wednesday27/09/202306:2719:06
Thursday28/09/202306:2819:04
Friday29/09/202306:3019:02
Saturday30/09/202306:3218:59
Sunday01/10/202306:3318:57
Monday02/10/202306:3518:55
Tuesday03/10/202306:3718:53
Wednesday04/10/202306:3818:50
Thursday05/10/202306:4018:48
Friday06/10/202306:4218:46
Saturday07/10/202306:4418:43
Sunday08/10/202306:4518:41
Monday09/10/202306:4718:39
Tuesday10/10/202306:4918:37
Wednesday11/10/202306:5018:34
Thursday12/10/202306:5218:32
Friday13/10/202306:5418:30
Saturday14/10/202306:5518:28
Sunday15/10/202306:5718:26
Monday16/10/202306:5918:24
Tuesday17/10/202307:0018:22
Wednesday18/10/202307:0218:19
Thursday19/10/202307:0418:17
Friday20/10/202307:0618:15
Saturday21/10/202307:0718:13
Sunday22/10/202307:0918:11
Monday23/10/202307:1118:09
Tuesday24/10/202307:1218:07
Wednesday25/10/202307:1418:05
Thursday26/10/202307:1618:03
Friday27/10/202307:1818:01
Saturday28/10/202307:1918:00
Sunday29/10/202306:2116:58
Monday30/10/202306:2316:56
Tuesday31/10/202306:2416:54
Wednesday01/11/202306:2616:52
Thursday02/11/202306:2816:51
Friday03/11/202306:3016:49
Saturday04/11/202306:3116:47
Sunday05/11/202306:3316:45
Monday06/11/202306:3516:44
Tuesday07/11/202306:3616:42
Wednesday08/11/202306:3816:41
Thursday09/11/202306:4016:39
Friday10/11/202306:4116:38
Saturday11/11/202306:4316:36
Sunday12/11/202306:4516:35
Monday13/11/202306:4616:33
Tuesday14/11/202306:4816:32
Wednesday15/11/202306:5016:31
Thursday16/11/202306:5116:29
Friday17/11/202306:5316:28
Saturday18/11/202306:5516:27
Sunday19/11/202306:5616:26
Monday20/11/202306:5816:25
Tuesday21/11/202306:5916:24
Wednesday22/11/202307:0116:22
Thursday23/11/202307:0216:22
Friday24/11/202307:0416:21
Saturday25/11/202307:0516:20
Sunday26/11/202307:0716:19
Monday27/11/202307:0816:18
Tuesday28/11/202307:1016:17
Wednesday29/11/202307:1116:17
Thursday30/11/202307:1316:16
Friday01/12/202307:1416:15
Saturday02/12/202307:1516:15
Sunday03/12/202307:1616:14
Monday04/12/202307:1816:14
Tuesday05/12/202307:1916:13
Wednesday06/12/202307:2016:13
Thursday07/12/202307:2116:13
Friday08/12/202307:2216:13
Saturday09/12/202307:2316:12
Sunday10/12/202307:2416:12
Monday11/12/202307:2516:12
Tuesday12/12/202307:2616:12
Wednesday13/12/202307:2716:12
Thursday14/12/202307:2816:12
Friday15/12/202307:2916:13
Saturday16/12/202307:3016:13
Sunday17/12/202307:3016:13
Monday18/12/202307:3116:13
Tuesday19/12/202307:3216:14
Wednesday20/12/202307:3216:14
Thursday21/12/202307:3316:15
Friday22/12/202307:3316:15
Saturday23/12/202307:3416:16
Sunday24/12/202307:3416:16
Monday25/12/202307:3516:17
Tuesday26/12/202307:3516:18
Wednesday27/12/202307:3516:19
Thursday28/12/202307:3516:19
Friday29/12/202307:3516:20
Saturday30/12/202307:3516:21
Sunday31/12/202307:3516:22

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 2023
» CSV Data for 2023

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