1. What is the Sunrise Sunset Calculator?

The Sunrise Sunset Calculator estimates the times of sunrise and sunset based on latitude and solar declination. It uses astronomical equations to predict when the sun will appear and disappear over the horizon.

2. How Does the Calculator Work?

The calculator uses these equations:

Where:

• \( Sr \) — Sunrise time in hours (local solar time)
• \( Ss \) — Sunset time in hours (local solar time)
• \( lat \) — Latitude in degrees (-90 to 90)
• \( dec \) — Solar declination in degrees (-23.5 to 23.5)

Explanation: The equations account for the Earth's tilt and the observer's position on Earth to calculate when the sun crosses the horizon.

3. Importance of Sunrise/Sunset Calculation

Details: Knowing sunrise and sunset times is crucial for agriculture, photography, outdoor activities, solar energy planning, and various scientific applications.

4. Using the Calculator

Tips: Enter latitude (-90 to 90 degrees) and solar declination (-23.5 to 23.5 degrees). The calculator will output sunrise and sunset times in hours (local solar time).

5. Frequently Asked Questions (FAQ)

Q1: What is solar declination?
A: Solar declination is the angle between the rays of the Sun and the plane of the Earth's equator, varying between -23.5° and +23.5° throughout the year.

Q2: Why does the equation use 15 in the denominator?
A: The Earth rotates 15 degrees per hour, so dividing the hour angle by 15 converts it from degrees to hours.

Q3: How accurate are these calculations?
A: These are approximate times that don't account for atmospheric refraction, elevation, or local topography. Actual times may vary by several minutes.

Q4: What about polar day/night?
A: When the argument of arccos is outside [-1,1], it means the sun is always above (polar day) or below (polar night) the horizon.

Q5: How to convert to local clock time?
A: You need to account for time zone, daylight saving time, and equation of time. These calculations provide solar time.