Sun Altitude Calculator

Latitude (φ in degrees):

Solar Declination (δ in degrees):

Calculate

Solar Altitude (A in degrees):

The sun altitude calculator helps determine the sun’s elevation angle at a specific location and time. This is crucial for various applications, including solar panel positioning, photography, astronomy, and agriculture. The altitude angle represents how high the sun appears in the sky from a given location.

Formula

The sun’s altitude angle can be calculated using the formula:

A = 90 − (φ − δ)

Where:

• A is the solar altitude angle in degrees.
• φ is the latitude of the observer in degrees.
• δ is the solar declination in degrees.

How to Use

1. Enter the latitude of your location.
2. Enter the solar declination for the specific day.
3. Click the Calculate button.
4. The calculator will display the sun’s altitude in degrees.

Example

If you are at a latitude of 40° and the solar declination for the given day is 23.5°, the altitude angle is:

A = 90 − (40 − 23.5)
A = 90 − 16.5
A = 73.5°

Thus, the sun is 73.5° above the horizon.

FAQs

1. What is the sun’s altitude?
   • The sun’s altitude is the angle between the sun and the observer’s horizon.
2. Why is the sun altitude important?
   • It helps in determining daylight hours, solar energy potential, and shading effects.
3. How does latitude affect sun altitude?
   • Higher latitudes experience lower sun angles, especially in winter.
4. What is solar declination?
   • It is the angle between the sun’s rays and the Earth’s equatorial plane, varying throughout the year.
5. How does time of day impact sun altitude?
   • The altitude is highest at solar noon and decreases toward sunrise and sunset.
6. Can this formula be used for any day of the year?
   • Yes, but the correct solar declination value for the day is required.
7. Where can I find solar declination values?
   • Solar declination can be found in almanacs or online solar position calculators.
8. Does the sun ever reach 90° altitude?
   • Yes, at the equator during the equinoxes and in tropical regions at certain times of the year.
9. Can this formula be used for the moon’s altitude?
   • No, the moon’s altitude depends on additional orbital factors.
10. How does atmospheric refraction affect sun altitude?

• Near the horizon, atmospheric refraction slightly increases the apparent altitude.

11. Is the altitude angle different for different hemispheres?

• Yes, the sun follows different paths in the Northern and Southern Hemispheres.

12. Why is solar altitude lower in winter?

• The Earth’s axial tilt causes the sun to appear lower in the sky during winter.

13. Does altitude affect sunrise and sunset times?

• Yes, locations at higher altitudes may see the sun earlier and for a longer duration.

14. What happens when the altitude angle is 0°?

• The sun is at the horizon, meaning it is either sunrise or sunset.

15. Can solar altitude be negative?

• Yes, when the sun is below the horizon, it results in negative values indicating nighttime.

16. What is the highest possible solar altitude?

• The maximum is 90°, occurring directly overhead at the subsolar point.

17. How do seasons impact solar altitude?

• Solar altitude is higher in summer and lower in winter.

18. How does solar altitude affect climate?

• Regions with higher solar altitude receive more direct sunlight and experience warmer temperatures.

19. Can solar altitude be used for solar panel placement?

• Yes, it helps in optimizing solar panel angles for maximum efficiency.

20. What is the difference between solar altitude and azimuth?

• Altitude measures height above the horizon, while azimuth measures the sun’s direction along the horizon.

Conclusion

The sun altitude calculator is a useful tool for determining how high the sun appears in the sky based on location and solar declination. Whether for astronomy, solar energy, or daily planning, understanding solar altitude is essential. Use the calculator above to find the sun’s altitude quickly and accurately.