Meet Aphelion, Earth's Farthest Point
Every year in early July, our planet reaches a point in its orbit called “aphelion.” The name comes from the Greek words ‘apo’ (away) and ‘helios’ (sun). On July 6, 2026, Earth will be at aphelion, putting it about 152.1 million kilometers (94.5 million miles)
away from the sun. This is more than 3 million miles farther than its closest point, or “perihelion,” which happens in early January. This occurs because Earth’s orbit isn’t a perfect circle; it’s a slight oval, or ellipse. While a few million miles sounds like a huge difference, it only changes our distance from the sun by a little over 3%. It’s a common and logical assumption that being closer to the sun makes us hotter, but aphelion’s timing during our summer proves this idea is a misconception.
The Real Reason for the Season: A Planetary Tilt
If distance isn't the main factor, what is? The answer lies not in our orbit’s shape, but in our planet’s posture. Earth is tilted on its axis by about 23.5 degrees. This tilt is the true engine of the seasons. As Earth journeys around the sun, this tilt means that for half the year, the Northern Hemisphere is angled more towards the sun, and for the other half, the Southern Hemisphere gets more direct exposure. This planetary lean is what causes summer and winter. When the Northern Hemisphere is tilted toward the sun, as it is around June, July, and August, we experience summer. Conversely, when it’s tilted away, we get the colder, shorter days of winter. The two hemispheres experience opposite seasons for this very reason.
Direct Sunlight and Longer Days
The tilt has two major effects that create summer’s warmth. First, it changes the angle at which sunlight hits the ground. During summer, the hemisphere tilted toward the sun receives sunlight more directly, almost like a flashlight shining straight down. This concentrates the sun's energy, leading to more effective heating. In winter, the same amount of sunlight is spread over a larger area because it arrives at a lower, more slanted angle, making it less intense. Second, the tilt gives us longer days. When your part of the world is leaning toward the sun, it spends more time in daylight during each 24-hour rotation. More hours of sunlight mean more time for the land, water, and air to heat up, and less time for them to cool down at night. This combination of direct rays and longer days is the powerful one-two punch that delivers summer heat, easily overpowering the minor cooling effect of being slightly farther from the sun.
Does Distance Have Any Effect at All?
While the axial tilt is the star of the show, the varying distance does play a minor role. Being at aphelion means Earth as a whole receives about 7% less solar energy than it does at perihelion. This has a subtle but noticeable impact on the seasons. For the Northern Hemisphere, having our summer during aphelion means our summers are slightly milder than they would be otherwise. Conversely, the Southern Hemisphere experiences summer during perihelion (its closest approach), which slightly intensifies its summer heat. The elliptical orbit essentially moderates the seasons in the north and exaggerates them in the south. However, the overwhelming driver of temperature remains the directness of the sun's rays, which is why we still sweat through July even when we're millions of miles farther from our star.
