Solar eclipse of December 14, 1917

{{short description|20th-century annular solar eclipse}}

{{Infobox solar eclipse|1917Dec14

| previous = Solar eclipse of July 19, 1917

| next = Solar eclipse of June 8, 1918

}}

An annular solar eclipse occurred at the Moon's ascending node of orbit on Friday, December 14, 1917,{{cite web|title=December 14, 1917 Annular Solar Eclipse|url=https://www.timeanddate.com/eclipse/solar/1917-december-14|publisher=timeanddate|access-date=1 August 2024}} with a magnitude of 0.9791. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring 4.6 days before apogee (on December 18, 1917, at 22:10 UTC), the Moon's apparent diameter was smaller.{{cite web|title=Moon Distances for London, United Kingdom, England|url=https://www.timeanddate.com/astronomy/moon/distance.html?year=1915&n=136|publisher=timeanddate|access-date=1 August 2024}}

This was the last of four solar eclipses in 1917, with the others occurring on January 23, June 19 and July 19.

The path of annularity crossed Antarctica. A partial eclipse was visible for parts of Antarctica, southern South America, and Australia. This annular eclipse is notable in that the path of annularity passed over the South Pole.

Eclipse details

Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.{{cite web|title=Annular Solar Eclipse of 1917 Dec 14|url=https://eclipsewise.com/solar/SEprime/1901-2000/SE1917Dec14Aprime.html|publisher=EclipseWise.com|access-date=1 August 2024}}

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|+December 14, 1917 Solar Eclipse Times

! Event

! Time (UTC)

First Penumbral External Contact

| 1917 December 14 at 07:09:48.7 UTC

First Umbral External Contact

| 1917 December 14 at 08:41:49.9 UTC

First Central Line

| 1917 December 14 at 08:43:56.6 UTC

Greatest Duration

| 1917 December 14 at 08:43:56.6 UTC

First Umbral Internal Contact

| 1917 December 14 at 08:46:08.6 UTC

Ecliptic Conjunction

| 1917 December 14 at 09:17:22.8 UTC

Equatorial Conjunction

| 1917 December 14 at 09:23:35.1 UTC

Greatest Eclipse

| 1917 December 14 at 09:27:19.7 UTC

Last Umbral Internal Contact

| 1917 December 14 at 10:08:36.2 UTC

Last Central Line

| 1917 December 14 at 10:10:45.3 UTC

Last Umbral External Contact

| 1917 December 14 at 10:12:49.1 UTC

Last Penumbral External Contact

| 1917 December 14 at 11:44:46.7 UTC

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|+December 14, 1917 Solar Eclipse Parameters

! Parameter

! Value

Eclipse Magnitude

| 0.97913

Eclipse Obscuration

| 0.95870

Gamma

| –0.91566

Sun Right Ascension

| 17h24m28.1s

Sun Declination

| -23°11'55.0"

Sun Semi-Diameter

| 16'15.0"

Sun Equatorial Horizontal Parallax

| 08.9"

Moon Right Ascension

| 17h24m36.7s

Moon Declination

| -24°04'53.4"

Moon Semi-Diameter

| 15'48.9"

Moon Equatorial Horizontal Parallax

| 0°58'02.6"

ΔT

| 20.2 s

{{clear}}

Eclipse season

{{See also|Eclipse cycle}}

This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.

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|+ Eclipse season of December 1917

! December 14
Ascending node (new moon) !! December 28
Descending node (full moon)

200px200px
align=center

| Annular solar eclipse
Solar Saros 121

Total lunar eclipse
Lunar Saros 133

Related eclipses

= Eclipses in 1917 =

= Metonic =

= Tzolkinex =

= Half-Saros =

= Tritos =

= Solar Saros 121 =

= Inex =

= Triad =

= Solar eclipses of 1916–1920 =

{{Solar eclipse set 1916–1920}}

= Saros 121 =

{{Solar Saros series 121}}

= Metonic series =

{{Solar Metonic series 1898–1982}}

= Tritos series =

{{Solar Tritos series 2005 April 8}}

= Inex series =

{{Solar Inex series 2004 October 14}}

Notes

{{reflist}}

References

{{Solar eclipse NASA reference|1901/SE1917Dec14A|19171214}}

{{Solar eclipses}}

1917 12 14

Category:1917 in science

1917 12 14

Category:December 1917