A total
solar eclipse
A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring the view of the Sun from a small part of Earth, totally or partially. Such an alignment occurs approximately every six months, during the eclipse season i ...
occurred at the Moon’s
descending node
An orbital node is either of the two points where an orbit intersects a plane of reference to which it is inclined. A non-inclined orbit, which is contained in the reference plane, has no nodes.
Planes of reference
Common planes of referenc ...
of orbit on Saturday, December 4, 2021,
with a
magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
of 1.0367. A total solar eclipse occurs when the Moon's
apparent diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular separation (in units of angle) describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the '' visual ...
is larger than the Sun's and the apparent path of the Sun and Moon intersect, blocking all direct sunlight and turning daylight into darkness; the Sun appears to be black with a halo around it. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring about 2.5 hours before
perigee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values.
Apsides perta ...
(on December 4, 2021, at 10:00 UTC), the Moon's apparent diameter was larger.
This eclipse was unusual as the path of the total eclipse moved from east to west across
West Antarctica, while most eclipse paths move from west to east. This reversal is only possible in polar regions. Its path across
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
crossed near
Berkner Island, traversed an arc over the continent and passed over
Shepard Island.
A partial eclipse was visible for parts of
Southern Africa
Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...
,
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
, and
Tasmania
Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...
.
Images
File:SE2021Dec04T.gif, Animated path
File:NASA's DSCOVR Satellite Spots Yesterday's Total Solar Eclipse Over Antartica (51727062271).png, NASA's DSCOVR Satellite photo
File:Royal Navy sailors observed 2021 partial solar eclipse off South Georgia (cropped).jpg, As observed by the Royal Navy (HMS Protector) off South Georgia
South Georgia is an island in the Atlantic Ocean, South Atlantic Ocean that is part of the British Overseas Territories, British Overseas Territory of South Georgia and the South Sandwich Islands. It lies around east of the Falkland Islands. ...
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.
Eclipse season
This eclipse is part of an
eclipse season
An eclipse season is a period, roughly every six months, when eclipses occur. Eclipse seasons are the result of the axial parallelism of the Orbit of the Moon, Moon's orbital plane (orbital inclination, tilted five degrees to the ecliptic, Earth ...
, 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
A fortnight is a unit of time equal to 14 days (two weeks). The word derives from the Old English term , meaning "" (or "fourteen days", since the Anglo-Saxons counted by nights).
Astronomy and tides
In astronomy, a ''lunar fortnight'' is hal ...
.
Related eclipses
Eclipses in 2021
*
A total lunar eclipse on May 26.
*
An annular solar eclipse on June 10.
*
A partial lunar eclipse on November 19.
* A total solar eclipse on December 4.
Metonic
* Preceded by:
Solar eclipse of February 15, 2018
* Followed by:
Solar eclipse of September 21, 2025
A partial solar eclipse will occur at the Moon’s descending node of orbit on Sunday, September 21, 2025, with a magnitude of 0.855. A solar eclipse occurs when the Moon passes between the Earth and the Sun, thereby totally or partly obscuring th ...
Tzolkinex
* Preceded by:
Solar eclipse of October 23, 2014
* Followed by:
Solar eclipse of January 14, 2029
Half-Saros
* Preceded by:
Lunar eclipse of November 28, 2012
* Followed by:
Lunar eclipse of December 9, 2030
Tritos
* Preceded by:
Solar eclipse of January 4, 2011
* Followed by:
Solar eclipse of November 3, 2032
Solar Saros 152
* Preceded by:
Solar eclipse of November 23, 2003
A total solar eclipse occurred at the Moon's descending node of orbit between Sunday, November 23 and Monday, November 24, 2003, with a magnitude of 1.0379. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or ...
* Followed by:
Solar eclipse of December 15, 2039
Inex
* Preceded by:
Solar eclipse of December 24, 1992
* Followed by:
Solar eclipse of November 14, 2050
Triad
* Preceded by:
Solar eclipse of February 3, 1935
A partial solar eclipse occurred at the Moon's ascending node of orbit on Sunday, February 3, 1935, with a magnitude of 0.739. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of ...
* Followed by:
Solar eclipse of October 5, 2108
Solar eclipses of 2018–2021
Saros 152
Metonic series
Tritos series
Inex series
Notes
References
solar-eclipse.de: ''The total solar eclipse of 12/04/2021''
{{commons category, Solar eclipse of 2021 December 4
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December 2021