Revolution: the four seasons
The second movement of the Earth is revolution: the Earth travels around the Sun along a path called an orbit. One complete trip takes 365 days: one year. Revolution, together with the tilted axis, produces the four seasons.
The seasons in the Northern Hemisphere
Because the axis is tilted, for part of the year our hemisphere leans towards the Sun (more light and heat: summer) and for part of the year it leans away from it (less light and heat: winter).
Summer begins. It is the longest day of the year: the most hours of sunlight.
Winter begins. It is the shortest day of the year: the fewest hours of sunlight.
In the Southern Hemisphere the seasons are the opposite. When we have winter in Spain, children in Argentina or Australia have summer. Summer there begins around 21 December, so they can spend Christmas on the beach!
A trip around the Sun really takes 365 ¼ days. Those quarter days add up, so every four years we add an extra day: 29 February. That year has 366 days and it is called a leap year. 2024 was a leap year, and the next one is 2028.
To talk about the past we use the past simple. Many verbs add -ed: The summer solstice takes place on 21 June → The summer solstice took place on 21 June (irregular); Kepler improves the telescope → Kepler improved the telescope; Russia launches the first satellite → Russia launched the first satellite, Sputnik, in 1957.