This Thursday, July 3rd, the Earth passed through the aphelion, the moment of the year when it is farthest from the Sun in its orbit.
The phenomenon, which occurs annually between July 2nd and 7th, happened exactly at 07:55 UTC, when the distance between both celestial bodies reached 152,098,455 kilometers.
This value contrasts with the perihelion, the point of closest approach to the Sun, which occurred on January 4th this year, at a distance of approximately 147.1 million kilometers. The difference between both orbital extremes is almost five million kilometers.
An elliptical orbit, not a perfect circle
As the state Astronomical Observatory reminds us, the Earth follows an elliptical orbit of 930 million kilometers, traveling at an average speed of 107,280 km/h, completing one revolution in 365 days and almost 6 hours, which explains the existence of leap years.
The speed is not constant: it increases when the planet approaches the Sun (perihelion) and decreases as it moves away (aphelion). This principle was formulated in the 17th century by the German astronomer Johannes Kepler, who stated that the imaginary line connecting a planet to the Sun sweeps equal areas in equal times.
Consequently:
- At perihelion, Earth can reach speeds of up to 110,700 km/h
- At aphelion, it decreases to around 103,536 km/h
This variation of over 7,000 km/h reflects the dynamic balance of solar gravity and the orbital momentum of our planet.
A barely noticeable yet key phenomenon
Although the aphelion does not cause appreciable seasonal changes —as the seasons are determined by the tilt of the Earth’s axis and not by the distance to the Sun—, this milestone illustrates how celestial mechanics condition fundamental rhythms in the life of the planet.
On average, Earth is 150 million kilometers from the Sun, a distance known as the astronomical unit, which serves as a parameter to measure other distances within the solar system.
For this reason, sunlight takes about eight minutes to reach the Earth’s surface, a reminder that even at its closest or farthest point, the astronomical scale places us in a cosmic dance of precision and proportion.
