In January, the Northern Hemisphere is tilted away from the Sun. This results in shorter days and less direct, weaker sunlight, causing winter weather despite being physically closer to the Sun.
The Earth's elliptical orbit affects the planet's distance from the Sun, but not the seasons. The seasons are determined by the amount of solar energy the Earth receives, which depends on the tilt of the Earth's axis and the time of day.
This short-term variation is primarily caused by the gravitational pull of the moon. The Earth and the moon orbit a common center of mass, called the barycenter. It is this barycenter, rather than the center of the Earth itself, that follows a smooth elliptical path around the sun. As the moon revolves around the Earth, it causes the Earth to wobble slightly ahead or behind in its orbital path, shifting the exact moment of perihelion by a few days.
The exact date and time of perihelion shift slightly from year to year. This is due to the gravitational influence of other planets, particularly the Moon and Jupiter, as well as the fact that our calendar doesn't align perfectly with Earth's orbit. Here is a short-term look at the event: during which month is the earth closest to the sun link
The Earth's orbit around the Sun is not a perfect circle, but rather an ellipse. This means that the distance between the Earth and the Sun varies throughout the year. At its closest point, the Earth is about 91.5 million miles (147 million kilometers) away from the Sun, and at its farthest point, it is about 94.5 million miles (152 million kilometers) away.
The word "perihelion" comes from the Greek words peri (near) and helios (sun). It refers to the specific point in a planet's orbit where it is physically closest to the star it revolves around.
| Feature | Perihelion | Aphelion | | :--- | :--- | :--- | | | Closest point to the Sun | Farthest point from the Sun | | Typical Month | Early January | Early July | | Average Distance | ~147.1 million km (91.4 million mi) | ~152.1 million km (94.5 million mi) | | Solar Radiation | ~7% more intense | ~7% less intense | In January, the Northern Hemisphere is tilted away
The 3% increase in solar intensity during perihelion does have a subtle effect, however. It makes winters in the Northern Hemisphere slightly milder than they would be if the orbit were perfectly circular, and it intensifies the summer heat in the Southern Hemisphere. The Changing Dates of Perihelion
Many people believe that the Earth is closest to the Sun during the summer months, but surprisingly, this is not the case. The Earth's orbit around the Sun is not a perfect circle, which means that the distance between the Earth and the Sun varies throughout the year. In fact, the Earth is closest to the Sun during a specific month that is often associated with cold weather.
To understand the orbit fully, you need two key vocabulary words: The seasons are determined by the amount of
While the difference in distance between perihelion and aphelion is only about , it still has minor impacts on our seasons:
You can also search for "Earth perihelion date" on NASA's main site or any reputable astronomy education page for confirmation.