2023 October 14 Annular Solar Eclipse
The same summer [431 B.C.], at the beginning of a new lunar month, the only time by the way at which it appears possible, the sun was eclipsed after noon. After it had assumed the form of a crescent and some of the stars had come out, it returned to its natural shape.
— Thucydides.
History of the Peloponnesian War
, trans. R. Crawley (1910), New York: E. P. Dutton
On October 14, 2023, an annular solar eclipse will be visible to fortunate observers
in the United States, Central America, and South America along a narrow band, approximately 130 miles (209 km) wide,
that will cross fifteen states from Oregon to Texas and continue southward to Brazil and the Atlantic Ocean.
Calculate local circumstances
Major U.S. Cities in the path of annularity: Eugene OR; Albuquerque, NM; Santa Fe, NM; San Antonio, TX
Use the form below to calculate the local circumstances. To find coordinates of cities or towns in the U.S. or its territories, or to convert between Degrees-Minutes-Seconds (DMS) and Decimal Degrees, use the respective buttons.
For other eclipses, try our
Solar Eclipse Computer. Times are
given in UT1; for help converting them to local time, see
U.S. Time Zones. Notes on the local eclipse circumstances are located at the bottom of this page.
View global map and circumstances (Eclipses Online Portal)
The
Eclipses Online Portal
provides diagrams and animations showing the global
circumstances and local circumstances at selected locations. The Portal is a
joint effort with
His Majesty's Nautical Almanac Office
, United Kingdom Hydrographic Office.
Times are given in UT1; for help converting them to local time, see
World Time Zone Map.
View global visibility map (The Astronomical Almanac)
Preliminary Eclipse Visibility Map from The Astronomical Almanac
(explanation of map).
For visibility maps of other eclipses, see Eclipses of the Sun and Moon.
View local circumstances at Natá, Panama (maximum duration of annularity on land)
Local circumstance diagram for Natá, Panama (location of maximum duration of annularity on land) from
The USNO
Eclipse Portal
.
View local circumstances in the Gulf of Parita, 8° 9' 28" N latitude and 80° 19' 20" W longitude (maximum duration of annularity)
Local circumstance diagram for the Gulf of Parita, 8° 9' 28" N latitude and 80° 19' 20" W longitude (location of maximum duration of annularity) from
Eclipses Online Portal
.
General eclipse resources
Notes
The table of local circumstances gives the UT1 time of each eclipse "event"
that is visible from the location. The
altitude
and
azimuth
of the Sun at each of the events is given as well. The azimuth is reckoned eastward from North. The altitude is corrected for
refraction
assuming standard atmospheric conditions.
The computation of Eclipse Local Circumstances is started by iteratively computing
topocentric positions of the Sun and Moon to find the time of Maximum Eclipse.
Another series of position computations is performed going backwards and
forwards from the time of Maximum Eclipse to find the times of contacts. The
solar and lunar angular diameters are calculated at each position using radius values adopted by the International Astronomical Union (Sun 696000 km; Moon 1737.4 km) to determine if contact conditions
have occurred. Lunar limb profiles and center of mass/center of figure corrections are not used.
After contact times have been computed, a check is made to determine if Sunrise
and/or Sunset occurred during the course of the eclipse. If so, the time of
Sunrise and/or Sunset is computed.
The body of the table contains the time of each contact point, the Sun's
topocentric position at that time, and its Position and Vertex
Angles. The time of sunrise or sunset is also noted in the table if it
occurs during the eclipse. The summary at the bottom contains the
Duration, Magnitude, and Obscuration.
The Position Angle of a given contact point on the solar limb is
measured eastward (counterclockwise) around the solar limb, from the point on the
Sun that is farthest north.
Vertex Angle is similar to Position Angle, except that it is
measured from the point on the Sun that has the highest local altitude.
Duration is the amount of time from the beginning of the eclipse to the
end.
Duration of Totality is the amount of time from the beginning of the
central phase eclipse to the end of the central phase. For an annular solar eclipse,
it will read Duration of Annularity.
Magnitude of the eclipse is the fraction of the apparent diameter of
the solar disk covered by the Moon at the time of greatest phase, expressed in
units of solar diameter.
Obscuration is the percentage of the area of the apparent solar disk
obscured by the Moon at maximum eclipse.
Additional eclipse defintions are available in the
Astronomical Almanac Glossary
.
