Today Is The Closest We Will Be to the Sun All Year!

The new year begins with planet Earth at the closest point in its orbit around the Sun, called perihelion, on January 2nd (today)! The Sun won’t appear noticeably larger in the sky – only about 3% larger. (Of course, you should never look at the Sun without proper eye protection. Remember, sunglasses are not sufficient for viewing the Sun.)

Reminder: Seasons are all due to the tilt of the earth, not the distance of the Earth from the Sun. During northern winter the north pole is tilted away from the Sun. Days are short and that makes it cold. According to NASA, The fact that we’re a little closer to the Sun in January doesn’t make much difference. Seasons are reversed in the southern hemisphere. When the north pole is tilted away from the Sun, as it is now, the south pole is tilted toward it. As a result, summer is in full swing south of the equator even as northerners are bracing for a long winter.

You may have learned in school that Earth orbits a certain distance from the Sun and that its orbit is nearly circular. The average distance from Earth to the Sun is called an astronomical unit, but since our orbit is not a perfect circle, it means sometimes we’re a bit closer to the Sun, and sometimes farther away. 

In fact, our distance from the Sun varies by around 3 million miles over the course of the year. That’s nearly 13 times the distance from Earth to the Moon.

At perihelion, Earth will be about 91.5 million miles from our local star. And when we’re at the farthest point, it’s called “aphelion.” That happens this year on July 5th, when we’ll be about 94.5 million miles away.

Between perihelion and six months later when the Earth is at its farthest from the Sun (aphelion) there is about a 6.7% difference in the intensity of the sunlight reaching the Earth. This is one of the reasons the seasons in the southern hemisphere are more extreme than in the northern hemisphere. Perihelion is also when the Earth is moving at its fastest in its orbit around the Sun, so if you run east at local midnight, you will be moving about as fast as you can (at least in Sun-centered coordinates) for your location.