Solar Eclipse Computer

U.S. Naval Observatory
Astronomical Applications Department

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Solar Eclipse of 2017 Aug. 21

Sun in Total Eclipse at this Location

Casper Mountain, Wyo. (Longitude W 106° 18' 52.0", Latitude N 42° 45' 9.0", Height 2480m)

August 21, 2017   Universal Time (UT1)Delta T: 69.4s
PhenomenonDayTime (UT1)Sun's Altitude (°)Sun's Azimuth (°)Position Angle (°)Vertex Angle (°)
Eclipse Begins2116:22:13.342.7118.1287.9329.4
Totality Begins2117:42:37.454.0142.6115.9143.1
Maximum Eclipse2117:43:50.154.1143.1
Totality Ends2117:45:05.054.2143.5283.1309.6
Eclipse Ends2119:09:28.559.1180.6110.9110.5


Duration2h 47m 15.2s
Duration of Totality2m 27.6s
Magnitude1.013
Obscuration100.0%

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