Our calendar year normally has 365 days, but the solar year – the time it takes for the Earth to orbit the Sun once – is about 365.24 days long.
This small difference accumulates over the years and must be balanced out. Therefore, every four years we have a leap year of 366 days to bring our calendar into line with the solar year.
These adjustments mean that the exact dates for events like the summer solstice can vary. 2024 is one such year in which the summer solstice occurs on June 20th.
This is based on precise astronomical calculations that determine the exact time when the sun reaches its highest point in the sky.
So over the years, the dates for the summer solstice may shift slightly. In some years it will be on June 21, in others, like 2024, on June 20. These shifts are normal and are the result of our calendar adjusting to the actual length of the year.
