In meteorology, autumn begins on September 1, however, the September equinox ushers in astronomical autumn in the Northern Hemisphere and spring in the South.
According to calculations by the National Astronomical Observatory of Spain, autumn 2023 in the Northern Hemisphere will begin on Saturday, September 23 at 06:50 UTC. The season lasts approximately 89 days and 21 hours and ends on December 22 with the onset of winter.
The beginning of autumn in the Northern Hemisphere is defined by the instant the Earth passes through the point in its orbit from which the center of the Sun crosses the celestial equator in its apparent motion southward. On the day when this happens, the length of day and night practically coincide. This situation is also known as Autumnal Equinox.
By the time autumn begins in the Northern Hemisphere, spring begins in the Southern Hemisphere.
What astrological phenomena can be observed?
In the fall of 2023, there will be two eclipses, one of the Sun and one of the Moon. The solar eclipse will occur on October 14 and will be annular and visible in the United States. In Spain, it is partially visible in the western Canary Islands, but with much smaller quantities. A lunar eclipse will occur on October 28, will be partial, and will be visible in the eastern United States, Europe, Africa, Asia and Australia. The partial phase (visible in Spain) starts at 19:35 UTC and ends at 20:53.
Other events of astronomical interest in the fall of 2023 will be heavy meteor showers, with a maximum on October 8, the Orionids, with a maximum on October 21, the Leonids, with a maximum on November 17, and the Geminids, with a maximum on December 14. Autumn Full Moons on September 29, October 28 and will occur on November 27.
The beginning of autumn can occur on four different dates on the calendar (September 21 to 24). Throughout the 21st century, autumn begins on September 22 and 23 (the official Spanish date), with its earliest beginning in 2096 and its latest beginning in 2003. Variations from one year to the next The calendar sequence of years (some leap years, others not) matches the duration of each Earth’s orbit around the Sun.
Early autumn is the time when the length of the year decreases most rapidly. At peninsular latitudes, the sun rises one minute later in the morning than the previous day, and sets one minute earlier in the afternoon. As a result, at the beginning of autumn, the time the sun stays above the horizon decreases by almost three minutes each day.
