To realign the calendar with the tropical year, a leap day is introduced (nearly) every four years. Eventually, the accumulated lag becomes so large that it falls on the following date. This means that the timing of the equinoxes and solstices slowly drifts apart from the Gregorian calendar, and the solstice happens about 6 hours later each year. However, our planet takes about 365.242199 days to orbit the Sun. Today's Gregorian calendar has 365 days in a common year and 366 days in a leap year. The date of the equinoxes and solstices varies because a year in our calendar does not exactly match the length of the tropical year-the time it takes the Earth to complete an orbit around the Sun. Local dates may vary depending on the time zone. Note: All dates refer to Coordinated Universal Time (UTC). A December 20 solstice is also rare, with the next one in the year 2080. The last December 23 solstice was in 1903 and the next one is in 2303. The December solstice can be on December 20, 21, 22, or 23.ĭecember 21 or 22 solstices happen more often than December 20 and 23 solstices. Find out why The December Solstice in the Calendar However, in most locations, the earliest sunset happens a few days before the solstice, while the latest sunrise occurs some days after it. The shortest day of the year is commonly associated with the latest sunrise and earliest sunset of the year. The December solstice marks the start of winter in the Northern Hemisphere and the start of summer in the Southern Hemisphere, according to one definition.Įquinox and solstice dates-years 1-2149 Sunrise and Sunset Times Lag Behind As the Earth travels toward the opposite side of its orbit, which it reaches in December, the Southern Hemisphere gradually receives more sunlight, and the subsolar point travels south.Įarth is tilted as it orbits the Sun, which is why equinoxes and solstices happen. In June, the Northern Hemisphere is tilted toward the Sun, and the subsolar point is north of the equator. The subsolar point moves north and south during the year because the Earth’s axis is tilted at an angle of about 23.4° in relation to the ecliptic, an imaginary plane created by Earth’s path around the Sun. The Sun: Our home star Why Does the Sun Move North and South? After that, the daily path of the Sun across the sky begins to creep northward again. On the day of the solstice, it reaches its southernmost point. In the months leading up to the December solstice, the position of sunrise and sunset creeps southward. Initially, the naming arose from observations of how the Sun’s apparent path across the sky changes slightly from one day to the next, which is caused by the same process as the subsolar point's movement described above. This is how the solstices got their name: the term comes from the Latin words sol and sistere, meaning “Sun” and “to stand still”. Why is the solstice so important for calendars? At the December solstice, which marks the southernmost point of its journey, it stops again to start its journey back toward the north.
Having reached its northernmost point at the June solstice, it starts moving southward until it crosses the equator on the day of the September equinox. Sun times at the South Pole in December What Does “Solstice” Mean?ĭuring the course of a year, the subsolar point-the spot on the Earth's surface directly beneath the Sun-slowly moves along a north-south axis. Places within the Antarctic Circle experience Midnight Sun, when the Sun does not set at night. Here, too, the effect is greater the farther a location is away from the equator. Longest Day in the SouthĬonversely, the day of the December solstice is the longest day of the year in the Southern Hemisphere. In tropical areas, the shortest day is just a little shorter than 12 hours in the temperate zone, it is significantly shorter and places within the Arctic Circle experience polar night, when the Sun does not rise at all. This effect is greatest in locations that are farther away from the equator. At the solstice, the North Pole's tilt away from the Sun is greatest, so this event marks the shortest day of the year north of the equator. Since the Northern Hemisphere is tilted away from the Sun in December, it receives less sunlight during the course of a day. Local times for this solstice worldwide.Sun rise/set and day length around this solstice.This corresponds to Friday, 22 December 2023, 03:27 UTC. In Odesa, Odessa, Ukraine: Friday, 22 December 2023, 05:27 EET (Change location) Business Date to Date (exclude holidays).
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