Ah, that enchanting time of year when the leaves turn gold and scarlet and the air becomes a little cooler and crisper. Autumn is a time of change, when nature prepares for the coming winter, and we can enjoy its beauty and unique mood. But when does this picturesque time of year actually start in 2024? Let's discover together when calendar and astronomical autumn begins , and what fascinating phenomena we can admire in the autumn sky.
Calendar autumn : a fixed point in the calendar
Calendar autumn is a period that always begins on September 23 and lasts until December 22, when the winter season arrives. This predetermined time is the same for the entire Northern Hemisphere, regardless of weather or weather conditions 
astronomical phenomena. This means that regardless of whether the outside temperature has already dropped significantly or we are still dealing with summer heat, on September 23 we can confidently announce the arrival of calendar autumn.
Astronomical autumn : a moving date related to the position of the Sun
Although the calendar autumn has a fixed date, the astronomical autumn is slightly more "moveable". Its beginning is determined by the position of the Sun relative to the Earth in the sky. Specifically, the moment when the Sun passes through the point of the autumn equinox, i.e. when day and night last the same length. In 2024, this event falls on September 23, coinciding with the first day of calendar autumn.
Autumn equinox: when day and night are of equal length
The autumn equinox is an extraordinary astronomical phenomenon that we observe every year around September 23. This is when the Sun passes through the equinox point, positioned on the celestial equator. At this point, day and night last the same length, then the days begin to gradually shorten and the nights lengthen - until the winter solstice.
Meteorological autumn : practical time frames
In addition to the calendar and astronomical autumn, we also distinguish meteorological autumn . This time of year, although slightly less "romantic", is extremely important from a practical point of view. Meteorologists define autumn 
meteorological period as the period from September 1 to November 30. Thanks to this, they can easily compare data from similar periods in different years, which is crucial in conducting statistics and analyses.
Thermal autumn : when the temperature drops below 15°C
Thermal autumn is another concept related to this time of year. This is the moment when average daily temperatures begin to fall between 5 and 15 degrees Celsius. This is when we can talk about the arrival of autumn in the meteorological and thermal sense, regardless of the calendar dates.
Phenological autumn : observing changes in nature
In addition to the calendar, astronomical and meteorological autumn, we also distinguish phenological autumn . It concerns changes occurring in nature, such as changes in the color of leaves, ripening of fruits or flights of birds. This is a fascinating period that we can observe and admire, tracing the changes taking place in the ecosystem around us.
Autumn nights full of attractions
As the days become shorter and the nights longer, we have a wonderful opportunity to observe various astronomical phenomena. Autumn is the time when we can admire meteor showers such as the Orionids and Draconids, as well as observe the oppositions of planets, including Jupiter and Uranus. There will also be opportunities to observe constellations typical of this time of year, such as Cassiopeus, Andromeda and Pegasus.
Galaxies, clusters and other cosmic wonders
The autumn sky hides many fascinating objects that we can admire even with the naked eye. These include such wonders as the spiral Andromeda Galaxy, the second brightest galaxy in the sky, and the globular cluster M15 
. Astronomy enthusiasts will also be able to observe the Pleiades and the brightest star in the autumn sky - Capella.
Sky observation: from the naked eye to the telescope
Although many objects in the autumn sky are visible to the naked eye, to take a closer look at them, it is worth using binoculars or a telescope. Even small astronomical telescopes will allow us to admire in their full glory such wonders as cloud bands in the atmosphere of Jupiter or the Andromeda Galaxy.
Autumn in the forest: a picturesque metamorphosis
Autumn is the time when the forest undergoes an extraordinary metamorphosis. First, the tree leaves begin to turn golden, scarlet and brown, and eventually fall, creating a picturesque carpet on the forest floor. It is a beautiful and magical time that is worth appreciating by walking among the trees and enjoying the charms of this unique season.
Autumn and children: time for nature observations
Autumn is a fascinating time also for the youngest. Children can independently observe the changes taking place in nature and even take a closer look at them using a microscope. For example, they can look at the structure of an autumn leaf, which is significantly different from a green summer leaf. This is a great opportunity to explain to them how all living organisms adapt to the passage of time.
Autumn people and compositions
Autumn is also a time when children can show their creativity by creating their own "autumn people" from chestnuts, acorns or other natural materials. It's great fun and at the same time an opportunity to learn about the characteristics of this season.
Welcome autumn with an open heart
Although we regret the end of summer, it is worth welcoming the coming autumn with an open heart. It is a time of change that brings extraordinary beauty and fascinating phenomena. Whether it's observing changes in nature, admiring the autumn sky, or creating autumn compositions - each of us can find a way to celebrate this special season. All you have to do is open your eyes and let yourself be enchanted by its magic.