How to Calculate Earth Curvature
What is Earth Curvature?
An Earth curvature calculator determines how far below the horizon the surface curves at a given distance. Earth's curvature is approximately 8 inches (20 cm) per mile squared: at 1 mile away, the ground is 8 inches below line of sight; at 10 miles, it is 66.7 feet below. This affects long-range visibility, laser leveling, and tower line-of-sight calculations.
Step-by-Step Guide
- 1Input viewing height above surface
- 2Calculate visible horizon distance
- 3Account for Earth's radius
Worked Examples
Input
35,000 feet altitude (plane)
Result
~235 miles visible horizon
Approximate range
Common Mistakes to Avoid
- ✕Not double-checking results
- ✕Ignoring edge cases
Frequently Asked Questions
What does this calculator do?
Input values
How do I use this calculator?
System calculates
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