Calculated Eclipse Summary
1. Eclipse Definition
Contact Times (UTC reference)
2. Observer Location
3. Local Visibility & Advanced Sky Geometry
4. Eclipse Path Map
5. Path Sampling & Timeline
| # | Latitude | Longitude | Distance from greatest eclipse | Approx. shadow offset | Center duration estimate |
|---|---|---|---|---|---|
| No samples generated. | |||||
6. Location Comparison & Trip Planning
| Location | Eclipse | Obscuration | Maximum | Central duration | Centerline distance | Boundary distance | Viewing score | Notes |
|---|---|---|---|---|---|---|---|---|
| No comparison locations added. | ||||||||
7. Eclipse Phase Visualization
Solar Viewing Safety
Never look directly at the Sun without appropriate solar protection. Ordinary sunglasses are not safe for eclipse viewing.
Use compliant eclipse viewers and front-mounted solar filters for optical equipment. During totality, follow authoritative guidance for the brief fully eclipsed phase only.
Understanding Solar Eclipse Paths
A solar eclipse path shows where the Moon’s shadow crosses Earth. During a total eclipse, observers inside the central path can experience complete coverage of the Sun for a short period. An annular eclipse also has a central path, but the Moon appears slightly smaller than the Sun. A bright ring remains visible around the Moon. People outside the central path may still observe a partial eclipse.
How This Calculator Works
This tool uses the greatest-eclipse coordinates, path bearing, modeled path length, and central-path width supplied by the user. It creates a sampled centerline and two approximate boundaries. Your observer coordinates are compared with those samples using great-circle distance. The nearest sampled centerline point is used to estimate path membership, boundary distance, and travel direction. Local obscuration is reduced gradually with distance from the centerline unless you provide a custom local value.
Using Eclipse Timing
Contact times describe important moments in the event. C1 marks the beginning of the partial phase. C2 begins totality or annularity when a central phase exists. Maximum eclipse occurs near the deepest alignment. C3 ends the central phase, while C4 ends the final partial phase. Times vary by location because the lunar shadow moves rapidly across Earth.
Planning a Viewing Location
For trip planning, compare several locations instead of relying on one point. Centerline locations often provide longer central phases, but weather, road access, elevation, crowding, and local horizon conditions also matter. The comparison table helps rank modeled locations by obscuration, path position, and solar altitude. The map can also show how far an observer lies from the centerline or path boundary.
Accuracy and Limitations
Professional eclipse predictions use detailed ephemerides and Besselian elements. This page does not replace those datasets. Its geometry is intentionally transparent and editable, making it useful for education, rough planning, demonstrations, and custom eclipse scenarios. Before travel, photography, or scientific work, verify timings and path limits with authoritative astronomical sources.
Common Eclipse Terms
| Term | Meaning | Why it matters |
|---|---|---|
| Centerline | Middle of the modeled central shadow path | Often near the longest central duration |
| Path width | Distance between northern and southern central limits | Shows how large the central viewing corridor is |
| Magnitude | Fraction of the Sun’s diameter covered | Describes eclipse depth |
| Obscuration | Percentage of the Sun’s apparent area covered | Describes visible solar area loss |
| Gamma | Shadow-axis distance from Earth’s center in Earth radii | Used in professional eclipse geometry |
Frequently Asked Questions
What is the path of totality?
It is the narrow region where the Moon completely covers the Sun during a total solar eclipse.
How wide is a solar eclipse path?
The width varies by eclipse and location. It can span well over one hundred kilometers for many total eclipses.
Can I see the eclipse from my location?
Enter your latitude and longitude. The calculator estimates whether you are inside the modeled central or partial viewing region.
What is eclipse magnitude?
Magnitude describes how much of the Sun’s apparent diameter is covered along the line through both disc centers.
What does obscuration percentage mean?
Obscuration is the percentage of the Sun’s apparent area covered by the Moon.
What are C1, C2, C3, and C4?
They are contact times marking the beginning and ending of partial and central eclipse phases.
Why does eclipse timing vary by location?
The Moon’s shadow moves across Earth, so each location intersects the shadow at different times.
How far am I from the centerline?
The tool finds the nearest sampled point on the modeled centerline and reports the great-circle distance.
Can this tool replace official eclipse predictions?
No. Use authoritative ephemeris-based predictions for exact contact times, scientific observations, and final travel decisions.
How can I safely observe a solar eclipse?
Use approved eclipse viewers or proper solar filters. Never rely on ordinary sunglasses for direct solar viewing.