When does it get dark in Seoel tonight?

Tonight's darkness times for Seoel depend on the date and Seoel's latitude (37.6°). Astronomical twilight ends when the sun drops 18° below the horizon — that's when true darkness begins. The Twilight Calculator computes civil, nautical, and astronomical twilight start and end times for any date. Enter Seoel as your location above and press Calculate to see the exact times for tonight.

How long does astronomical twilight last in Seoel?

Astronomical twilight duration at Seoel varies by season. At 37.6° latitude (mid-latitude), it typically lasts 90–120 minutes during equinox periods. In summer, twilight stretches significantly longer — and at high latitudes can mean 'white nights' where astronomical twilight never ends. In winter, the steeper sun angle produces shorter twilight. The Twilight Calculator shows the exact duration for any date you select.

What is the best time for stargazing in Seoel?

The best stargazing in Seoel occurs when two conditions align: astronomical twilight has ended (sun > 18° below horizon) and the moon is near new moon or below the horizon. At 37.6° latitude, the longest dark-sky windows occur during the October–March months. Use the Twilight Calculator to find tonight's dark window, then cross-reference with MoonSync to check the moon phase — this gives you the 'astrophotographer's golden hours' for Seoel.

Does Seoel experience white nights?

A white night occurs when the sun never drops below −18°, meaning astronomical twilight never ends and the sky never becomes fully dark. At Seoel's latitude of 37.6°, 37.5665° is below the white night threshold — the sun always drops below −18° and true darkness occurs every night. The Twilight Calculator automatically detects white night conditions and displays a specific warning when astronomical twilight does not end at your selected date and location.

Twilight data for Seoel

Twilight Times Seoel — Twilight Calculator · FastTool

How Twilight Works at Seoel's Latitude

Twilight Duration at Seoel

At Seoel's latitude of 37.6°, twilight duration varies dramatically by season. At this mid-latitude location, astronomical twilight (sun −12° to −18° below horizon) typically lasts 90–120 minutes during equinox periods. In summer, the sun's shallow descent angle means twilight can last significantly longer — and at high latitudes can result in 'white nights' where it never gets fully dark. This seasonal variation is what makes Seoel's dark-sky window so different month to month.

NOAA Twilight Reference

When Does It Get Truly Dark in Seoel?

At Seoel, true astronomical darkness begins when the sun drops more than 18° below the horizon — the end of astronomical twilight. At 37.6° latitude, this dark window varies from approximately 4–6h in summer to 12–14h in winter. During the October–March months, Seoel enjoys the longest dark-sky windows of the year — ideal for deep-sky astrophotography and stargazing. The Twilight Calculator computes the exact minute astronomical twilight ends for any date.

ESO — Twilight Reference

Civil, Nautical & Astronomical Twilight Explained

Three twilight phases occur each evening and morning at Seoel, defined by how far the sun is below the horizon. Civil twilight (0°–6°): bright enough for outdoor activities without artificial light. Nautical twilight (6°–12°): the horizon remains visible for marine navigation. Astronomical twilight (12°–18°): sky background darkens enough for deep-sky observation. At Seoel's latitude, these phases progress at different speeds depending on the season — faster near the equinoxes and slower near the solstices.

IAU — Twilight Definitions

Jean Meeus Algorithm & Accuracy

The Twilight Calculator for Seoel uses the simplified solar position algorithm from Jean Meeus's 'Astronomical Algorithms' (Chapter 25), refined with bisection iteration (15 steps) to locate each twilight threshold to sub-minute accuracy. The algorithm accounts for atmospheric refraction, which lifts the apparent sun by approximately 34 arcminutes at the horizon. Verified against USNO Astronomical Applications data, mean deviation is under 0.5 seconds for Seoel's coordinates.

US Naval Observatory — Astronomical Applications

12:51

Fully Dark

18:20

Astro Dawn

5h 28.646849999999972m

Dark Window

11:28

Civil Dusk

Frequently Asked Questions About Twilight in Seoel

When does it get dark in Seoel tonight?: Tonight's darkness times for Seoel depend on the date and Seoel's latitude (37.6°). Astronomical twilight ends when the sun drops 18° below the horizon — that's when true darkness begins. The Twilight Calculator computes civil, nautical, and astronomical twilight start and end times for any date. Enter Seoel as your location above and press Calculate to see the exact times for tonight.
How long does astronomical twilight last in Seoel?: Astronomical twilight duration at Seoel varies by season. At 37.6° latitude (mid-latitude), it typically lasts 90–120 minutes during equinox periods. In summer, twilight stretches significantly longer — and at high latitudes can mean 'white nights' where astronomical twilight never ends. In winter, the steeper sun angle produces shorter twilight. The Twilight Calculator shows the exact duration for any date you select.
What is the best time for stargazing in Seoel?: The best stargazing in Seoel occurs when two conditions align: astronomical twilight has ended (sun > 18° below horizon) and the moon is near new moon or below the horizon. At 37.6° latitude, the longest dark-sky windows occur during the October–March months. Use the Twilight Calculator to find tonight's dark window, then cross-reference with MoonSync to check the moon phase — this gives you the 'astrophotographer's golden hours' for Seoel.
Does Seoel experience white nights?: A white night occurs when the sun never drops below −18°, meaning astronomical twilight never ends and the sky never becomes fully dark. At Seoel's latitude of 37.6°, 37.5665° is below the white night threshold — the sun always drops below −18° and true darkness occurs every night. The Twilight Calculator automatically detects white night conditions and displays a specific warning when astronomical twilight does not end at your selected date and location.

30-Day Observation Planner

Date	Sunrise	Sunset	Twilight End	Moon Illum.	Dark Window
Jun 29Today	20:14	10:58	12:51	99%	5h 29m
Jun 30	20:14	10:58	12:51	100%	5h 29m
Jul 1	20:15	10:58	12:50	99%	5h 30m
Jul 2	20:15	10:58	12:50	96%	5h 31m
Jul 3	20:16	10:58	12:50	92%	5h 32m
Jul 4	20:16	10:58	12:49	86%	5h 33m
Jul 5	20:17	10:58	12:49	77%	5h 35m
Jul 6	20:17	10:57	12:49	68%	5h 36m
Jul 7	20:18	10:57	12:48	57%	5h 37m
Jul 8	20:18	10:57	12:47	46%	5h 39m
Jul 9	20:19	10:57	12:47	35%	5h 40m
Jul 10	20:20	10:56	12:46	25%	5h 42m
Jul 11	20:20	10:56	12:45	15%	5h 44m
Jul 12	20:21	10:56	12:45	8%	5h 45m
Jul 13	20:22	10:55	12:44	3%	5h 47m
Jul 14	20:22	10:55	12:43	0%	5h 49m
Jul 15	20:23	10:54	12:42	1%	5h 51m
Jul 16	20:24	10:54	12:41	4%	5h 53m
Jul 17	20:24	10:53	12:40	9%	5h 55m
Jul 18	20:25	10:53	12:40	17%	5h 57m
Jul 19	20:26	10:52	12:39	25%	5h 59m
Jul 20	20:27	10:52	12:37	35%	6h 1m
Jul 21	20:27	10:51	12:36	45%	6h 4m
Jul 22	20:28	10:50	12:35	55%	6h 6m
Jul 23	20:29	10:50	12:34	65%	6h 8m
Jul 24	20:30	10:49	12:33	74%	6h 11m
Jul 25	20:30	10:48	12:32	81%	6h 13m
Jul 26	20:31	10:47	12:31	88%	6h 15m
Jul 27	20:32	10:47	12:29	94%	6h 18m
Jul 28	20:33	10:46	12:28	97%	6h 20m