1. What is the Length of Daylight Calculation?

The Length of Daylight calculation estimates the number of daylight hours at a given latitude on a specific date (determined by solar declination). It's based on astronomical principles of Earth's rotation and axial tilt.

2. How Does the Calculator Work?

The calculator uses the daylight length equation:

Where:

• \( DL \) — Daylight length in hours
• \( \phi \) — Latitude in degrees (-90 to 90)
• \( \delta \) — Solar declination in degrees (-23.5 to 23.5)

Explanation: The equation calculates the time between sunrise and sunset based on the Earth's geometry relative to the Sun.

3. Importance of Daylight Calculation

Details: Knowing daylight length is crucial for agriculture, solar energy planning, architectural design, and understanding seasonal changes in daylight patterns.

4. Using the Calculator

Tips: Enter latitude (-90 to 90 degrees) and solar declination (-23.5 to 23.5 degrees). Positive values are for northern hemisphere/summer declination, negative for southern hemisphere/winter declination.

5. Frequently Asked Questions (FAQ)

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

Q2: What's the maximum possible daylight hours?
A: At the poles during summer solstice, daylight can be 24 hours. At the equator, daylight is always about 12 hours.

Q3: How accurate is this calculation?
A: It provides theoretical daylight length. Actual sunrise/sunset times may vary slightly due to atmospheric refraction and local topography.

Q4: Can this calculate daylight for any date?
A: Yes, if you know the solar declination for your desired date (which changes throughout the year).

Q5: What about daylight saving time?
A: This calculates actual daylight hours. Daylight saving time adjustments are political and not accounted for in this astronomical calculation.