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Earth farthest from the sun today

Earth farthest from the sun: Orange sunset over water, with a boat in the foreground.
View at EarthSky Community Photos. | Ragini Chaturvedi captured this sunset in late June from Sandy Hook, New Jersey. “Magnanimous it was,” she wrote. Thank you, Ragini!

Earth farthest from the sun

Planet Earth reached aphelion – our most distant point from the sun – at 7 UTC on July 4, 2022. That’s 2 a.m. Central Daylight Time in North America. It’s been a hot summer already in parts of the Northern Hemisphere. And Earth’s aphelion always comes in July, in the midst of Northern Hemisphere summer (and Southern Hemisphere winter). So you know our distance from the sun doesn’t cause Earth’s seasons.

Looking for Earth’s exact distance from the sun at 2022’s aphelion? It’s 94,509,598 miles (152,098,455 km).

The fact is, Earth’s orbit is almost, but not quite, circular. So our distance from the sun doesn’t change much percentagewise (a little over 3%). Today, we’re about 3 million miles (5 million km) farther from the sun than we will be six months from now. And it’s in contrast to our average distance from the sun of about 93 million miles (150 million km).

By the way, the word aphelion comes from the Greek words apo meaning away, off, apart and helios, for the Greek god of the sun. Apart from the sun. That’s us, around now.

What causes the seasons?

The seasons aren’t due to Earth’s changing distance from the sun. We’re always farthest from the sun in early July during northern summer and closest in January during northern winter.

Instead, the seasons result from Earth’s tilt on its axis. Right now, it’s summer in the Northern Hemisphere because the northern part of Earth is tilted most toward the sun. We’re receiving the sun’s rays most directly

Meanwhile, it’s winter in the Southern Hemisphere because the southern part of Earth is tilted most away from the sun. The more indirect sunlight causes cooler temperatures.

Read more: Why Earth has 4 seasons

Earth’s varying distance from the sun does affect the length of the seasons, though. That’s because, at our farthest from the sun, like now, Earth is traveling most slowly in its orbit. That makes summer the longest season in the Northern Hemisphere and winter the longest season on the southern half of the globe.

Conversely, winter is the shortest season in the Northern Hemisphere, and summer is the shortest in the Southern Hemisphere, in each instance by nearly five days.

Earth at perihelion and aphelion 2001 to 2100

Diagram showing Earth's orbit with aphelion and perihelion distances labeled.
Diagram showing aphelion and perihelion. Image via NASA.

Closest and farthest points tied to solstices?

The short answer is no. It’s true that Earth is farthest from the sun every year in early July, about two weeks after the June solstice. And it’s true that Earth is closest to the sun every early January, about two weeks after the December solstice. Is it a coincidence? Yes, it is. Over the long course of time, the dates of Earth’s closest and farthest points to the sun shift with respect to the solstices.

According to timeanddate.com:

Due to variations in the eccentricity of the Earth’s orbit, the dates when the Earth reaches its perihelion or aphelion are not fixed. In 1246, the December solstice was on the same day as the Earth reached its perihelion. Since then, the perihelion and aphelion dates have drifted by a day every 58 years. In the short term, the dates can vary up to two days from one year to another.

Mathematicians and astronomers estimate that in 6430, over 4000 years from now, the perihelion will coincide with the March equinox.

Visual size difference when Earth farthest from sun

Solid yellow circle with thin rim of gray around it.
At aphelion, our most distant point from the sun, the sun does appear a bit smaller in our sky. This composite image illustrates the difference. This image consists of 2 photos, taken just days away from a perihelion (Earth’s closest point to sun) in January 2016, and an aphelion (Earth’s farthest point from sun) in July 2017. The gray rim around the sun (actually the perihelion photo) illustrates that, as seen in our sky, the sun is about 3.6% bigger at perihelion than aphelion. This difference is, of course, too small to detect with the eye (and never look at the sun without proper filters). Photo by Peter Lowenstein of Mutare, Zimbabwe.
Three images of the sun appearing successively each a slightly different size.
Animation of the image above … the size difference of the sun between Earth’s perihelion (closest point) and aphelion (farthest point).

Bottom line: Planet Earth reaches its most distant point from the sun for 2022 on July 4. Astronomers call this yearly point in Earth’s orbit our aphelion.

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Why isn’t the hottest weather on the year’s longest day?

The post Earth farthest from the sun today first appeared on EarthSky.

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