Today, Thursday 3 July 2025at 21:54 Italian timethe earth is located in aphelionthat is, at the point of its orbit in which it is more far from the sun. It is an astronomical event that occurs every year in the first days of July, when our planet moves away until 152,087,738 kilometers from our star, about 4.94 million kilometers more Compared to the minimum distance achieved a Januaryduring the perihelion.
But there is a detail that may seem contradictory: Why right now, while we are further away from the sun, is the heat unbearable? The answer is not in the distance, but in the inclination of the Earth’s axisa determining factor for the seasons and for the intensity of the sun radiation we receive.
The terrestrial orbit is elliptical and the sun is not in the center: for this reason the distances change during the year
We are used to imagining the orbit of the earth as a perfect circle, but in reality it is one light ellipsejust as the first Kepler law. This means that the distance between the earth and the sun is not constantbut varies during the year. In aphelium, we are more distant; in Perdie, closer.
The Sun is not located in the center of the Ellissebut in one of the two fires. This is why between the closest point and the farthest one there is one difference of almost 5 million kilometersequal to about 3.5% of the average land-sell distancewhich is of 149.6 million kilometers.
A real difference, of course, but which translates only into a 6.5% less of solar energy received. In addition, the gravity of the other planets it can affect the form of the Earth’s orbit in a slightest part, causing small deviations From year to year: nothing, however, that has a significant impact on the climate or seasons.
The real cause is the inclination of the earth’s axis
The reason why It is hot despite the greatest distance from the sun is found in the inclination of the Earth’s axiswhich is inclined to 23 ° 27 ‘ with respect to the orbit plane. It is this inclination that determines The seasonsand above all the amount of solar energy per square meter which arrives in a certain point of the earth.
During the northern summer, the north hemisphere is more exposed to sunlightwho arrive more direct and with greater intensity. Even if we receive the 6.5% less energy Due to the distance, the high sun in the sky and the days very long They compensate this difference widely.
In our latitudes, between summer and winter solstice, we move from an inclination of the rays almost perpendicular to one much more oblique. This causes one difference in solar energy up to 250%: in summer, therefore, The radiation per square meter is more than double compared to winter.
An impressive fact, which makes it clear why July is among the hottest months of the year, even if the earth is at the point farthest from the sun. In short, to warm us less or more depending on the distancebut the angle with which he strikes us. And today, while we are in the heart of the Boreal summer, our hemisphere is inclined in the direction of the star, receiving all the energy necessary to make us sweat, even if we find ourselves in the aphelium.
