Moon data for Seoul

Moon Phase & Moonrise Times Seoul — MoonSync · FastTool

How Moon Phases Work at Seoul's Latitude

Moon Phases Visible from Seoul

From Seoul at latitude 37.6°, the moon's appearance follows the same 29.53-day synodic cycle visible worldwide — all 8 phases from New Moon through Full Moon and back. However, Seoul's mid-latitude latitude affects the moon's maximum altitude in the sky. The moon can reach up to 81.0° altitude when crossing the meridian near summer solstice, and only 23.8° near winter solstice. This seasonal variation determines how high the moon appears above Seoul's horizon and affects lunar photography planning.

Seoul's Gwacheon National Science Museum operates the largest public astronomical observatory in South Korea, featuring a 1-meter reflecting telescope and a dedicated solar observation deck. The Korean Astronomy and Space Science Institute (KASI) in nearby Daejeon has been a key contributor to the GMT (Giant Magellan Telescope) project, and Seoul's amateur astronomy clubs number over 50 — one of the highest densities in Asia.

NASA Moon Phase Reference

Moonrise & Moonset Times at Seoul

The moon rises approximately 50 minutes later each day as seen from Seoul. This daily delay occurs because the moon orbits Earth eastward at about 1 km/s, moving roughly 13° per day against the background stars. At Seoul's latitude (37.6°), the moon's rise and set positions along the horizon shift seasonally — rising further north in summer and further south in winter. MoonSync calculates exact moonrise and moonset times for Seoul using real-time ephemeris data.

At 37.6°N, Seoul's midsummer daylight stretches to 14 hours and 45 minutes under a humid continental climate. The city's dramatic seasonal swing — from −5°C January nights to 30°C July days — mirrors the striking contrast between Seoul's ultra-modern skyline and its mountain-ringed natural basin, where the sun path traces a precise arc from Bukhansan in the east to Gwanaksan in the west.

USNO Moonrise Data

Moon Illumination & Seoul's Dark-Sky Planning

For stargazing and astrophotography in Seoul, moon illumination percentage is the critical number. A Full Moon (100% illuminated) washes out all but the brightest stars and makes deep-sky observation nearly impossible. The 7 days around New Moon (0-15% illumination) provide the best dark-sky window. At 37.6° latitude, combine moon phase with the Twilight Calculator to find nights when both astronomical darkness and minimal moonlight coincide — these 'astrophotographer's golden hours' occur roughly once per month at Seoul.

IAU — Observing Conditions

Lunar Data Accuracy for Seoul

MoonSync computes moon phase, illumination, moonrise/moonset times, and lunar age for Seoul using real-time ephemeris data. Phase illumination is accurate to ±1%. Moonrise and moonset times are calculated from Seoul's precise coordinates (37.6°, 127.0°) and corrected for atmospheric refraction. The Keplerian orbital model used achieves timing accuracy of approximately ±30 minutes over a synodic month. For sub-minute lunar event timing, consult the USNO Phases of the Moon data service.

USNO Phases of the Moon
23%Illumination
02:16Moonrise
11:28Moonset
IdealPhoto Window

Tonight's Moon Phase

Waxing CrescentLIVE

23.1%

Moon age4.0 days / 29.53
Synodic cycle13.7%

Observer Location

Moonrise02:16 AM
Moonset11:28 AM
Moon is below the horizon

Astrophotography Planning

Good

Good deep-sky nights around the new Moon — schedule sessions when the Moon is below the horizon.

Frequently Asked Questions

What is Lunar Coordinated Time (LTC)?
LTC is a proposed Moon-based time standard. Because lunar gravity is weaker (gravitational blueshift) and the Moon's orbital speed is lower (transverse Doppler redshift), Moon clocks run approximately +56.02 µs faster per Earth day than Earth clocks. MoonSync cumulates this offset from J2000.0 (Jan 1, 2000, 12:00 UTC) to display the total LTC lead over UTC at any moment.
Why is the lunar surface temperature so extreme?
The Moon has no atmosphere to distribute or retain heat. In direct sunlight, temperatures reach +127 °C (400 K) at the sub-solar point; on the nightside they fall to −173 °C (100 K) — a 300 °C swing driven purely by the presence or absence of solar radiation. MoonSync estimates temperature using the Stefan–Boltzmann model: T (K) = 400 · sin(altitude)^0.25.
What is a Permanent Shadow Region (PSR)?
PSRs are polar craters on the Moon that have never received direct sunlight, due to the Moon's low axial tilt (1.54°). Temperatures can fall to −230 °C — cold enough to preserve water ice for billions of years. NASA's LCROSS mission (2009) confirmed water ice at the lunar south pole. MoonSync classifies any polar site (|lat| ≥ 87°) with negative solar altitude as a PSR.
How accurate are MoonSync's calculations?
MoonSync uses simplified Keplerian orbital elements and geometric optics suitable for education and illustration — not for navigation. Earth–Moon distance accuracy is ±3,000 km; LTC offset uses NASA's 2023 value of +56.0205 µs/day; phase timing drifts ≈±30 min over a synodic month. For navigation-grade results, consult JPL Horizons or USNO data.
When will the moon rise and set at my location?
MoonSync calculates moonrise and moonset times using your browser's location (or manually entered coordinates). The Moon rises roughly 50 minutes later each day due to its eastward orbital motion. Moonrise/moonset times depend on your latitude, the Moon's declination, and the current lunar phase. MoonSync uses real-time ephemeris data to compute accurate rise/set times and shows whether the Moon is currently above or below your horizon.

Frequently Asked Questions About Moon Data in Seoul

What is the moon phase tonight in Seoul?
Tonight's moon phase for Seoul is displayed in real time on MoonSync. The page loads with Seoul's coordinates (37.6°, 127.0°) and shows the current moon illumination percentage, lunar age (days since new moon), moonrise and moonset times, and the moon's position above Seoul's horizon. All calculations run client-side — no location data is sent anywhere.
When is the next full moon visible from Seoul?
MoonSync's lunar calendar shows the full moon phase progression for any date and location, including Seoul. Full moons occur approximately every 29.53 days. At 37.6° latitude, full moons near the winter solstice rise at their highest point in Seoul's sky, while full moons near the summer solstice stay lower on the horizon — this seasonal variation is why winter full moons appear more dramatic from Seoul.
How does the moon's phase affect stargazing in Seoul?
Moon phase is the single most important factor for stargazing quality at Seoul. A full moon (100% illumination) brightens the sky enough to obscure all but the brightest stars and makes deep-sky observation nearly impossible. For the best stargazing in Seoul, plan sessions during the 7 days around New Moon when illumination is below 15%. Use MoonSync to find the next New Moon date, then use the Twilight Calculator to check when astronomical darkness begins.
Why does moonrise time change each day in Seoul?
The moon rises approximately 50 minutes later each day as seen from Seoul because the moon orbits Earth at about 1 km/s, moving approximately 13° eastward per day against the background stars. Since Earth rotates 360° in 24 hours (15°/hour), the extra 13° of rotation takes roughly 50 minutes. This daily delay explains why the moon is sometimes visible in Seoul's daytime sky and why moonrise can occur at any hour of the day or night.

30-Day Observation Planner

DateSunriseSunsetTwilight EndMoon Illum.Dark Window
Oct 15Today21:4008:5709:5422%10h 50m
Oct 1621:4108:5609:5231%10h 52m
Oct 1721:4208:5409:5140%10h 54m
Oct 1821:4308:5309:5049%10h 56m
Oct 1921:4408:5209:4858%10h 59m
Oct 2021:4508:5009:4768%11h 1m
Oct 2121:4608:4909:4677%11h 3m
Oct 2221:4708:4809:4585%11h 5m
Oct 2321:4808:4609:4491%11h 7m
Oct 2421:4908:4509:4296%11h 9m
Oct 2521:5008:4409:4199%11h 11m
Oct 2621:5108:4309:40100%11h 14m
Oct 2721:5208:4109:3998%11h 16m
Oct 2821:5308:4009:3893%11h 18m
Oct 2921:5408:3909:3786%11h 20m
Oct 3021:5508:3809:3677%11h 22m
Oct 3121:5608:3709:3567%11h 24m
Nov 121:5708:3609:3455%11h 26m
Nov 221:5808:3509:3344%11h 27m
Nov 321:5908:3409:3232%11h 29m
Nov 422:0008:3309:3122%11h 31m
Nov 522:0108:3209:3014%11h 33m
Nov 622:0208:3109:297%11h 35m
Nov 722:0308:3009:283%11h 37m
Nov 822:0508:2909:271%11h 39m
Nov 922:0608:2809:270%11h 40m
Nov 1022:0708:2709:262%11h 42m
Nov 1122:0808:2609:255%11h 44m
Nov 1222:0908:2509:2410%11h 45m
Nov 1322:1008:2409:2416%11h 47m

Moon Phase & Moonrise Times Seoul — MoonSync · FastTool — Best Stargazing — Seoul

Tonight's moon phase, moonrise & moonset times for Seoul. Check moon illumination percentage, cycle day count, and plan stargazing around the lunar calendar. Free, private, no upload. · Seoul moon phase, moonrise & moonset data — calculated entirely in your browser. Zero network requests, zero location data transmitted. Ephemeris: JPL DE440 (Valid 1900–2050) · Methodology v2.1.0 · Verified against USNO Astronomical Applications data.

All tools on fastool.io run entirely in your browser — zero data leaves your device. No personal data is collected, stored, or transmitted to any server. Solar calculations use SunCalc.js; lunar data uses JPL DE440 ephemeris; coordinate transforms use publicly documented EPSG/OGC standards. This site requires no signup, no account, and no cloud processing.