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Related to Antarctic Circle: International Date Line
Antarctic Circle,imaginary circle on the surface of the earth at 66 1-2°S lat., i.e., 23 1-2° north of the South Pole. It marks the southernmost point at which the sun can be seen at the winter solsticesolstice
[Lat.,=sun stands still], in astronomy, either of the two points on the ecliptic that lie midway between the equinoxes (separated from them by an angular distance of 90°).
..... Click the link for more information. (about June 22) and the northernmost point of the southern polar regions at which the midnight sunmidnight sun,
phenomenon in which the sun remains visible in the sky continuously for 24 hr or longer, occurring only in the polar regions. The midnight sun is due to the fact that the plane of the earth's equator is tilted about 23 1-2° to the plane of the ecliptic (the
..... Click the link for more information. is visible.
Antarctic Circle[‚ant′ärd·ik ′sər·kəl]
The parallel of latitude approximately 66°32′ south of the Equator.
the imaginary circle around the earth, parallel to the equator, at latitude 66° 32ʹ S; it marks the southernmost point at which the sun appears above the level of the horizon at the winter solstice