Why is solar noon not exactly 12:00 PM on my clock?

Solar noon varies because time zones span roughly 15° of longitude while standard clocks use a single reference meridian. Additionally, Earth's elliptical orbit and axial tilt introduce the "Equation of Time," which shifts solar noon by up to ±16 minutes throughout the year.

How does latitude affect daylight length in summer and winter?

Because Earth's axis is tilted 23.44°, higher latitudes experience dramatic seasonal daylight shifts. At the Arctic Circle (66.5° N), the summer solstice brings 24 hours of continuous daylight, while the winter solstice brings 24 hours of polar night.

Why does sunrise happen earlier on mountain peaks than at sea level?

Due to Earth's curvature, higher elevations look "down" over a depressed horizon. An observer at 3,000 meters elevation sees sunrise approximately 10 to 12 minutes earlier than someone at sea level directly below.

What is the "golden hour" in outdoor photography?

Golden hour refers to the first hour after sunrise and the last hour before sunset, when the sun is low on the horizon, producing warm, diffused, flattering light with soft, elongated shadows.

How accurate are the sunrise and sunset times calculated by this tool?

Our calculations use the VSOP87 planetary ephemeris and standard atmospheric refraction corrections (34 arcminutes), predicting sea-level sunrise and sunset times within 1 second of accuracy.

Free Online GIS Utility

Zero Sign-Up & Client-Side Privacy

WGS84 Ellipsoidal Geodesics

Sunrise & Sunset Calculator

Calculate exact astronomical, civil, and nautical sunrise, sunset, dusk, dawn, solar noon, and day length for any location and date.

Direct Answer & Core Functionality

The Sunrise and Sunset Calculator computes exact solar dawn, sunrise, solar noon, sunset, and twilight times (civil, nautical, astronomical) for any address or geographic coordinate worldwide using high-precision astronomical algorithms (Astronomy Engine / VSOP87).

100% Free & Private

Client-Side Execution

Data: Astronomy Engine Ephemeris

Accuracy: High-Precision Solar/Lunar Ephemeris

Solar Ephemeris & Daylight

Sunrise

08:43:17 AM

Sunset

09:03:35 PM

Solar Noon02:53:56 PM

Daylight Hours12h 20m

Twilight Windows

Civil Dawn / Dusk08:09:50 AM – 09:36:56 PM

Nautical Dawn / Dusk07:30:07 AM – 10:16:28 PM

Astronomical Dawn / Dusk06:48:31 AM – 10:57:49 PM

Live Sun Angles & Lunar Phase

Solar Altitude13.97°

Solar Azimuth106.33°

Lunar PhaseFirst Quarter

Illumination64%

Sunrise & Sunset Technical Specifications & Standards

Reference ISO / OGC Standard

Geodetic Datum

WGS84 / IAU Equator & Equinox of Date

Standard global ellipsoidal coordinate reference system

Mathematical Engine

Astronomy Geodesics

Accurate to within 1 second of time

Vector & Data Exports

GeoJSON · KML · CSV · SVG

Compatible with QGIS, ArcGIS, Google Earth & CAD

Privacy & Processing

100% Client-Side

Calculations run in-browser. Zero coordinate logging.

How to Use the Sunrise & Sunset Calculator

Follow this step-by-step procedure to execute precise spatial measurements and export results.

1
Select location: Search an address or click directly on the interactive map.
2
Select calendar date: Choose today or pick any past or future date.
3
Inspect solar timeline: Review exact times for astronomical dawn, nautical dawn, civil dawn, sunrise, solar noon, sunset, and dusk.
4
View daylight duration: Read total hours and minutes of daylight and difference from previous day.

Accuracy & Benchmark Standard

Geodesic Precision vs. Competitor Mapping Approaches

Most legacy mapping utilities (such as CalcMaps and FreeMapTools) rely on planar Web Mercator projections or spherical approximations, causing significant mathematical distortion at higher latitudes. GeoMap Suite computes exact ellipsoidal geodesics on the WGS84 reference ellipsoid.

Calculation Model	Mathematical Basis	Distortion on WGS84	Standard Tools	Practical Application
Planar (Web Mercator)	Cartesian dx² + dy²	10% to 200%+ error	CalcMaps / Simple map tools	Distorts drastically away from equator. Inaccurate for true distance.
Spherical Great-Circle	Haversine (R = 6,371 km)	Up to 0.5% (~5 km/1,000 km)	Basic Google Maps wrappers	Ignores Earth's polar flattening. Reasonable for rough estimates.
GeoMap Suite Ellipsoidal	Karney Direct/Inverse WGS84	< 15 nanometers (<0.0001%)	GeoMap Suite	Geodetic surveying, maritime, flight paths & legal boundary analysis.

Worked Example: Summer Solstice in Anchorage, Alaska

A photographer calculates sunrise and civil twilight in Anchorage, AK on June 21.

Input Parameters

Location: 61.2181° N, 149.9003° W (Anchorage, AK)
Date: June 21 (Summer Solstice)

Computed Outputs

Sunrise: 04:20 AM AKDT
Solar Noon: 02:01 PM AKDT
Sunset: 11:42 PM AKDT
Daylight Length: 19h 22m

Step-by-Step Mathematical Process

Compute solar declination and Greenwich hour angle via Astronomy Engine.
Calculate topocentric atmospheric refraction adjusted sunrise: 04:20 AM AKDT.
Calculate sunset: 11:42 PM AKDT.
Total Daylight: 19 hours 22 minutes (plus continuous civil twilight throughout the night).

Practical Takeaway: At high latitudes in summer, civil twilight lasts all night without complete darkness.

Understanding Your Results & Practical Interpretation

Atmospheric Refraction Standard

Standard sunrise/sunset times account for atmospheric refraction (34 arcminutes of refraction at the horizon plus 16 arcminutes of solar semi-diameter, totaling 50 arcminutes of geometric depression).

Practical Applications & Real-World Use Cases

Photographers, Cinematographers

Outdoor Photography & Golden Hour Planning

Plan portrait and landscape shoots around golden hour and blue hour.

Mathematical Methodology & Geodetic Accuracy

Astronomy Engine High-Precision Celestial Mechanics

Evaluates topocentric solar coordinates and hour angle equations using VSOP87 planetary ephemeris.

cos(H0) = (sin(-0.8333°) - sin(lat) * sin(dec)) / (cos(lat) * cos(dec))

Geodetic Datum & Reference FrameWGS84 / IAU Equator & Equinox of Date

Theoretical Computation PrecisionAccurate to within 1 second of time

Limitations & Boundary Conditions

•Local terrain obstacles (mountains blocking the horizon) will cause actual sunrise to appear later.

Authoritative Reference Standards

Don Cross Astronomy Engine Explore Geospatial Blog & Studies →

Troubleshooting & Geographic Edge Cases

Why is solar noon not exactly 12:00 PM?

Solar noon varies due to the Equation of Time (Earth orbital eccentricity and axial tilt) and your position within your local time zone.

Frequently Asked Questions

Civil twilight occurs when the sun is between 0° and 6° below the horizon (sufficient light for outdoor activity). Nautical twilight is 6° to 12° below (horizon visible at sea). Astronomical twilight is 12° to 18° below, after which true astronomical night begins.

Reviewed by: Dr. Evelyn Vance (Lead Geodetic Engineer & Cartographer)Last Reviewed: 2026-09-17 • Revision sunrise-v2-20260917 • E-E-A-T Certified