According to calculations by the National Astronomical Observatory, dependent on the Geographic Institute, summer 2022 will finally arrive this Tuesday, June 21. Specifically at 11 hours, 13 minutes and 48 seconds (Spanish time). And it will remain with us for 94 days and 3 hours, until the autumn equinox occurs on September 23. But why do we land in the summer season on the 21st and not any other?
The summer solstice can occur on at most three different dates on the calendar: June 20, 21 and 22, although during the 21st century it will only occur on June 20 and 21. The earliest onset will occur in the year 2096, and the latest onset will occur in the year 2003. The variations from year to year are due to how the length of the Earth's orbit around the Sun (known as the tropic year) fits together. in the sequence of calendar leap years.
Because the beginnings of the seasons are not a whim, but are defined as those moments in which the Earth is in a certain position in its orbit around the Sun. In the case of summer, this position corresponds to the point at which The center of the Sun, seen from Earth, reaches its maximum northern declination (+23º 27′).
When that happens, the maximum height of the Sun at noon hardly changes for several days, a circumstance called the summer solstice (which means 'Sun still'). However, this is not a maxim for everyone: the seasons are opposite in the northern hemisphere and in the southern hemisphere, so when we welcome summer here, in the southern hemisphere they do the same but with winter.
More astronomical events
Summer will be loaded with spectacular stellar phenomena. On July 13, the so-called 'deer moon' will occur. The Moon will be located on the opposite side of the Earth, like the Sun, and its face will be fully illuminated early in the evening. In addition, that same month the Delta Aquarid meteor shower will occur: this meteor shower will have its maximum between July 28 and 29. Discovered by the Greek astronomer Ptolemy, its origin is in the comet 96p-Machholz, whose cosmic dust produces rain that can be 'enjoyed' throughout the month. However, its name comes from the constellation of Aquarius, where meteors are brightest. This is a constellation of the southern hemisphere, so the show will be more intense in more southern latitudes.
In August we can enjoy the last supermoon of the year, the 'grain moon', specifically on August 12. In addition, the famous Perseids will also return and, although they can be seen throughout the month, the days with the most 'shooting stars' (misnamed because they are not stars in any case, but rather meteoroids that cross the atmosphere) will be the August 12 and 13.
The Perseids, also known as 'Tears of Saint Lawrence' because they coincide with this holiday, are a meteor shower originating from the cloud of dust and rocks that the comet Swift-Tuttle has left behind in each of its orbits. around the Sun. This comet orbits the Sun approximately every 130 years, and was discovered in 1862. With a size of around 26 kilometers in diameter, it is currently the largest object that periodically approaches the Earth. Every year at this time the Earth crosses the trail of the comet and, when the small particles that were released from it touch the Earth's atmosphere, luminous traces are produced, which this year will be 'eclipsed' in some way by a moon almost full on peak day.
To say goodbye to summer, on September 16 we will be able to see Neptune in opposition. This planet will be at its closest approach to Earth and its face will be completely illuminated by the Sun. It will be brighter than at any other time of the year throughout the night. It will look like a small blue dot.