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In this photograph in Las Fotos de los Lectores de La Vanguardia we can appreciate a sunrise from Esplugues de Llobregat looking towards Barcelona, where the sun promises another hot day in this almost summery spring.
With the change of season, the sun crosses the equator line of our planet and heads north. At the spring equinox, the duration of day and night is practically the same in all places on Earth.
The sun only rises in the east on the spring and fall equinoxes. In winter it comes, more or less, from the southwest (which is why we have few hours of natural light), while in summer it comes from the northeast direction.
The intense blue color of the sky on these spring days is due to the fact that sunlight, when it reaches the Earth's atmosphere, is scattered in all directions by gases and particles found in the air.
Blue light spreads more than other colors because it travels in shorter, smaller waves. This is the reason why we can appreciate blue colors more clearly.
