1. What is a Sunlight Hours Calculator?

Definition: This calculator estimates the number of daylight hours at a specific location and date based on latitude and solar declination.

Purpose: It helps astronomers, gardeners, architects, and energy planners understand daylight duration for various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• Sunlight — Duration of daylight (hours)
• φ (phi) — Latitude of the location (degrees)
• δ (delta) — Solar declination angle (degrees)

Explanation: The formula calculates the fraction of the day that the sun is above the horizon based on Earth's axial tilt and the observer's latitude.

3. Importance of Sunlight Calculation

Details: Accurate sunlight duration estimation is crucial for solar energy systems, agriculture, architectural design, and understanding seasonal variations.

4. Using the Calculator

Tips:

• Enter latitude between -90° (South Pole) and 90° (North Pole)
• Solar declination ranges between -23.45° and +23.45° (Earth's axial tilt)
• For specific dates, use: δ ≈ 23.45° × sin(360° × (284 + n)/365) where n is day number

5. Frequently Asked Questions (FAQ)

Q1: What is solar declination?
A: The angle between the Sun's rays and Earth's equatorial plane, varying seasonally due to Earth's tilt.

Q2: Why does the formula give 24 hours at high latitudes in summer?
A: This represents the "midnight sun" phenomenon when the sun doesn't set for 24 hours.

Q3: How accurate is this calculation?
A: It provides theoretical maximum daylight hours. Actual sunlight may vary due to atmospheric conditions and terrain.

Q4: What's the solar declination on equinoxes?
A: Approximately 0° (March and September equinoxes).

Q5: How do I find my latitude?
A: Use GPS coordinates, online maps, or a smartphone mapping application.