Solar eclipse contact comparison
Compare the next local eclipse at two entered places. Start on 1 April 2024 to follow the North American eclipse; each table row gives its predicted UTC contact and Sun altitude.
Each location finds its next geometric local eclipse after 2024-04-01. Check the dates before comparing: widely separated places may meet different events. Each contact includes Sun altitude; a contact below the horizon cannot be observed there. C2/C3 exist for total or annular phases.
| Place | Type | Contact | Predicted UTC | Sun altitude | Visibility |
|---|---|---|---|---|---|
| A | total | C1 · partial begins | 2024-04-08 17:20:30 UTC | 60.8° | Above horizon |
| A | total | C2 · central phase begins | 2024-04-08 18:37:47 UTC | 65.83° | Above horizon |
| A | total | Maximum | 2024-04-08 18:40:00 UTC | 65.8° | Above horizon |
| A | total | C3 · central phase ends | 2024-04-08 18:42:14 UTC | 65.75° | Above horizon |
| A | total | C4 · partial ends | 2024-04-08 20:00:29 UTC | 58.16° | Above horizon |
| B | partial | C1 · partial begins | 2024-04-08 18:10:36 UTC | 53.12° | Above horizon |
| B | partial | Maximum | 2024-04-08 19:25:33 UTC | 43.37° | Above horizon |
| B | partial | C4 · partial ends | 2024-04-08 20:36:21 UTC | 31.42° | Above horizon |
Read this calculation
Contacts compare the apparent topocentric solar and lunar disks; the Moon’s moving shadow intersects a rotating curved surface.
On 8 April 2024, the published NASA centre-line prediction at 18:40 UTC was 31° 43.2′ N, 97° 22.2′ W, with central duration 4 min 23.7 s and a path about 192 km wide. Two minutes later the centre had moved to 32° 17.0′ N, 96° 42.0′ W. This moving geographic path is distinct from the sequence of contacts at one fixed observer.
The values above are predictions, not clocked observations. The National Solar Observatory team’s report documents observing totality at Eagle Pass, Texas, on 8 April, including clearing clouds and visible corona. Compare your own UTC-timed contact record with this table at your actual coordinates. The first/last bright limb, lunar mountains, clock offset and location shift the recorded contacts; preserve those details with the observation.
Local visibility requires the Sun to be above the horizon at each contact. Partial eclipses have no central C2/C3 phase. An annular phase leaves a bright solar ring, whereas a total phase blocks the full photosphere. Use appropriate solar viewing equipment during partial and annular phases; an ordinary camera viewfinder is not a safe solar viewer.
A clocked observation at the path edge
On 8 April 2024 near the northern limit at Stephenville, Texas, Quaglia, Irwin and Pessi recorded photospheric disappearance at 18:39:06.6 UTC and reappearance at 18:39:20.3 UTC: 13.7 seconds of totality. They used a GPS-referenced event timer while viewing the flash spectrum, with camera recordings as a further check.
| Same observation site | Totality duration |
|---|---|
| Clocked observation | 13.7 s |
| Authors’ terrain-aware prediction | 12.9 s |
| Prediction minus observation | −0.8 s |
The report discusses manual reaction uncertainty of roughly one to two seconds. Lunar limb relief and the adopted solar radius matter especially near the path limit. This is a comparison with the authors’ detailed prediction, not a calibration of the simple disk calculator above at an approximate city coordinate.
The observers’ report, Journal for Occultation Astronomy 2024-4, pages 3–9