July 21, 2026 · Castlereagh, Northern Ireland
Sunrise in Castlereagh today is at 05:16. Day length is 16h 28m. See below for sunset, solar noon, dawn and dusk — all times calculated astronomically for Castlereagh's coordinates and updated daily.
Castlereagh lies at 55°N. At this latitude, day length varies significantly through the year — from roughly 7–8 hours in midwinter to 16–17 hours at midsummer.
Sunrise shifts earlier through spring and later through autumn — changing fastest near the equinoxes and barely at all near the summer and winter solstices. See the year chart to visualise how sunrise and sunset times shift month by month for Castlereagh.
The longest day in Castlereagh is around 17h 16m (around June 21). The shortest is around 7h 15m (around December 21). Days are currently getting shorter — losing about 3 minutes per day.
| Month | Sunrise | Sunset | Day length |
|---|---|---|---|
| January | 08:39 | 16:27 | 7h 48m |
| February | 07:49 | 17:29 | 9h 40m |
| March | 06:42 | 18:25 | 11h 42m |
| April | 06:25 | 20:24 | 13h 59m |
| May | 05:21 | 21:21 | 15h 60m |
| June | 04:48 | 22:01 | 17h 13m |
| July | 05:06 | 21:54 | 16h 47m |
| August | 05:58 | 21:00 | 15h 2m |
| September | 06:55 | 19:45 | 12h 51m |
| October | 07:50 | 18:30 | 10h 40m |
| November | 07:52 | 16:26 | 8h 34m |
| December | 08:39 | 15:59 | 7h 19m |