Summer Solstice 2020 : the date is coming soon... to Understand the astronomical phenomenon in two minutes

SUMMER 2020. What is the date of the next summer solstice, which marks our entry into the season-titled ? How does this astronomical phenomenon... and why does

Summer Solstice 2020 : the date is coming soon... to Understand the astronomical phenomenon in two minutes

SUMMER 2020. What is the date of the next summer solstice, which marks our entry into the season-titled ? How does this astronomical phenomenon... and why does it not always place a "21" ? Explanations.

Summary Date of the summer solstice, summer Solstice 2020 summer Solstice and length of day summer Solstice and sunset times for Feast of the summer solstice, the Definition of the summer solstice summer Solstice or the longest day

[updated June 19, 2020 at 16h02] The date of the summer solstice does not correspond to a "21" in June, the proof is for the year 2020 : in our northern hemisphere, the astronomical phenomenon takes place Saturday, June 20, at close to midnight Paris local time (see details here). It will then mark both the entry in the season of summer, the longest day of the year and the beginning of the decline of the duration of the day... until the winter solstice, which takes place on December 21, 2020.

The "solstice" is when the sun is furthest from the equator, which rhyme alternately with the maximum or minimum period of the day on Earth. The summer has always held twice in the year, involving the seasons opposite in the northern and southern hemispheres (the summer solstice is to the end of December in the southern hemisphere). On the contrary the solstice, it is the equinox, fall or spring.

Programmed artificially by the scientists on June 1 of each year, the "summer weather" allows experts from the sky to perform their calculations more easily. The summer solstice, him, may, according to the year occur between 19 and 22 June. To understand in five minutes the shift in the dates of the solstice each year, click here.

What do we know about the date of the summer solstice ?

In our Northern hemisphere, the summer solstice corresponds to the longest days of the year. The period of time between sunrise and sunset can exceed 16 hours, compared to just 8 hours at the end of December at the time of the winter solstice. The phenomenon arises from the natural slope of the Earth relative to the plane on which it revolves around the Sun. Without this gap, the seasons as we know them on our planet would not exist ! In our world, the summer solstice sounds so the beginning of the summer season. mid-way between the equinoxes of spring and autumn , when night and day have exactly the same length. Make a date truly special.

The date of the summer solstice is usually the first information that we seek to know home gardeners, lovers of the hottest days, or simply for those who like to be fixed on the dance of the seasons. On this point, it is relatively simple : the summer solstice typically occurs on June 21. But be careful, there are exceptions. In 2016, for example, it was scheduled for Monday, June 20 at 22h34 GMT. France living in GMT+2 since the time change, it was held, in france in any case, June 21 at 00h34 . The previous year, the summer solstice took place on 21 June at 16: 37:55 U. T. C (18: 37 Paris time) exactly according to the figures provided by the Institut de mécanique céleste et de calcul des ephemerides (IMCCE).

The calendar year (365 days) does not match to the tropical year, that is to say, the exact amount of time that it takes for our sun to rotate around our star © Vadim Sadovski_123RF

But it may happen, as in 2008, 2012 or 2020, as the summer solstice to intervene on June 20. This phenomenon can also occur on the 22 June, as was the case in 1975 (the next occurrence will take place in... 2203). More rarely, the summer solstice may finally reach a June 19. This will be in 2488. Because the exact time of the solstice as it evolves each year. It is a good measure of the trajectory of the Earth relative to the Sun, and our ability to adapt our system to schedule and our schedule on these movements astronomical. In fact, the calendar year (365 days) does not match to the tropical year , that is to say, the exact amount of time that it takes for our sun to revolve around our star (365 days, 5 hours, 48 minutes and 45 seconds). If this "offset" is corrected by leap years, the elliptical path of the Earth also plays a role that shifts the solstice each year.

When is the summer solstice 2020 ?

on The side of our Northern hemisphere, in 2020, the summer solstice, which marks the 1st day of the summer season of our calendar, was held Saturday, June 20, 2020 (eve of the feast of music) 23h43 Paris time (21h43 universal time). The latest edition of the " summer solstice "fell" on Friday, June 21, at 15h54 (French time). In 2017, it wasn't for the date astronomical fall Tuesday, 20 June, the day of many events of bachelor that are already marked by the heat wave in several departments of France. The summer solstice has, this time, of place, June 20, when the date the most common for the occurrence of the phenomenon of astrological is that of 21 June.

Here is when are the summer solstices of the following years :

summer Solstice 2021 : June 21, summer Solstice, 2022 : June 21, summer Solstice, 2023 : June 21, summer Solstice 2024 : June 20, summer Solstice 2025 : June 21, summer Solstice 2026 : 21 June What is the link between the summer solstice and the day length ?

The most obvious impact of the phenomenon of the summer solstice is the lengthening of the maximum duration of the day visible. In Paris, in 2015, the duration between the sunrise and the sunset is 16 hours, 10 minutes and 48 seconds on June 21, its annual maximum. The star appeared to the east as soon 5h47 to disappear at 21h58. From the next day, the duration of the day started to go down gradually. At first imperceptibly, then faster and faster until the autumn equinox. The Latin etymology of the word solstice reflects this progression : sol (sun) and sistere (to stop) recall that it was at this time that the length of day is changing the least rapidly.

The next autumn equinox will take place on 22 September. © Aleksandr Prokopenko_123RF

If the length of the day reaches its peak on the occasion of the solstice, it is not the same everywhere. The more we approach the arctic circle, the more it increases. Therefore, and by way of example, during the summer solstice of 2015 always, in Perpignan, is the Sun at 15 hours and 19 minutes after being lifted on the 21st of June. In Lille, this difference reached 16 hours and 29 minutes. In Stockholm, in Sweden, the length of the day has reached 18 hours and 37 minutes. In Trondheim, north of Norway, the Sun shines for 20 hours and 35 minutes and is almost not lowered under the horizon : there was no night to speak of. There, the Sun stops outright lie from the summer solstice at the arctic circle. In the southern hemisphere, the phenomenon is reversed. At the time of the summer solstice in our world, Antarctica is plunged into darkness. however, be Careful : if it is theoretically at the time of the summer solstice the sun rises earlier in the morning or goes to bed later in the evening, this principle is not always rigorously accurate. In question, the race slightly elliptical Earth around the Sun, marked by accelerations and slowdowns. The irregular form of our planet also plays a role.

at what time the sun will go down there during the next summer solstice ?

Saturday, June 20, 2020, the day of the summer solstice this year but also the longest day, the sun will set at 21h53 in Paris , according to the website after having informed the capital for 16 hours 02. In Brest, the moon will lie squarely at 22h18 (for a duration of sunshine total of 15h58 in the day). In Marseille, the sun will draw his bow as soon 21h18 the same, June 20. To learn more about the hour of sunset depending on the cities, go on the specialized site

What is the history of the feast of the summer solstice ?

The summer solstice traditionally gives rise to the great feast of the fire of Saint Jean, which is celebrated every 24 June . This festival honors the summer season is inspired by the cult of the sun in Ancient times. A practice originally a pagan celebration of the harvest taken over by the catholic church, which has been christianized to be built in celebration of light, in particular thanks to the famous fires of St. John lighted at dusk.

► Visit our special page "Fête de la Saint-Jean"

What is the definition of the summer solstice ?

How to define the summer solstice ? It is the time of year when the path of the Sun, viewed from Earth, reaches its maximum northerly (in the northern hemisphere) or southern (in the southern hemisphere). In other words, during the summer solstice at our latitude, the Sun passes at its zenith at the Tropic of Cancer. In reality, this is not a movement of our star, which produces this phenomenon, but the revolution of the Earth around the Sun. In effect, the axis of our planet is inclined 23 degrees to the plane of the ecliptic, that is to say, the plane on which the Earth moves relative to the sun. So we have the illusion of a moving Sun in the sky. But a good drawing is sometimes better than a long speech...

The summer solstice is represented in the bottom left © Graphies.theca - Fotolia
Date Of Update: 19 June 2020, 10:57