Earth will move closer to the sun between tonight and tomorrow, Wednesday, January 3, 2024. This event is called perihelion, that is the point in the orbit of a planet or other astronomical body where it is closest to the sun.

Every year our planet reaches its closest point to the sun in an elliptical orbit. The phenomenon produces a maximum orbital velocity, accelerating 3,420 km per hour above average.

This amazing event, which takes place in early January, is known in meteorology as perihelion day. The Greek word literally means ‘around the sun’.

The point on the trajectory where the Earth is located the closest point to the sun is known as perihelion, while the farthest point on the path is known as aphelion. Because Earth is at perihelion, it will be about 3% closer to the Sun than in early July, when Earth is at its aphelion.

Is there a connection between the December solstice and January perihelion?

Although we wanted to relate the perihelion to the recent The December solstice, which occurred from December 21 to 23, 2023, It is purely coincidental that they fall within a period of about two weeks per year.

The December solstice marked the sun’s southernmost journey across our sky. During this solstice, Earth’s southern hemisphere is tilted more toward the sun. And now it is summer in this hemisphere. Meanwhile, the northern half of the globe is tilted more toward the sun during the December solstice. We normally say that winter begins on this solstice in our half of the world.

The date of Earth’s perihelion varies as the centuries pass. Although these two astronomical events are now about two weeks apart, they were closer a few centuries ago. In 1246 AD they even happened on the same day. Since then, the dates of perihelion and aphelion have changed by one day every 58 years. In the short term, dates can vary by up to two days from year to year.

Mathematicians and astronomers estimate that perihelion will coincide with the March equinox in 6430, 4000 years from now.

Beware of the sun

Although the variation in Earth’s distance from the Sun is not very great, during the Southern Hemisphere summer our planet receives more solar energy when it is closer to the Sun. Ultraviolet radiation must therefore be taken into account, which, according to the Ecuadorian Institute of Meteorology and Hydrology (Inamhi), will be at very high levels in much of the inter-Andean, Amazonian and insular region. (JO)