Earth at its maximum distance from the Sun: why it's still hot

Said like this, it may bring back sad memories of middle school to some, but it is simple: the Earth is tilted by 23.5 degrees and this causes the seasons: just take an apple, stand in front of the dining table, put another fruit on the table, for example an orange, which will be the Sun for us. With the apple, which will be our Earth, for six months we pass above the table, with about 23 degrees up to a maximum from which we descend and for another six we stay below in the same way, the visualization of the difference due to the inclination of the Earth is quickly done, however approximate. Incidentally, when we are with the apple on the table going down it will be the autumn equinox, in the opposite case the spring equinox,

Back to us. The point of maximum proximity, perihelion, is instead the point of the orbit in which the Earth is closest to the Sun, and this year it was on January 4, 2025, when it arrived at only 147.1 kilometers from the Sun, so 5 million kilometers less, about 3% difference.

Our misconception arises from figures like these, which we have been stumbling upon since the first grade and which are completely wrong: the Earth's orbit is indeed an ellipse, as prescribed by Kepler's laws, but it is almost a circle if the difference between perihelion and aphelion is so small!

From when we are kids, we get the idea in our heads that the Sun's orbit is shaped like an egg, which fortunately it isn't: it would cause us a lot of problems, in fact, if it were just like the picture.

A difference of 3% between the positions of minimum and maximum distance from the Sun corresponds to an increase in energy falling on the Earth from the Sun of about 6%, which is very little.