Happy Aphelion 2020!
July is summer in the northern hemisphere and you might think this means we are closer to the Sun. This is a common misconception. Earth is actually farther from the Sun in July and on July 4th it is at its farther distance in orbit around the Sun. We call this aphelion.
This farthest point occurs July 4, 2020 at 7:34 am EDT or 11:34 am UTC. At that time the distance from Earth’s center to the Sun’s center will be 94,507,635 mi (152,095,295 km).
Earth orbit around the Sun is an ellipse. Its closest approach to the Sun in this orbit is called perihelion and its farthest is called aphelion.
Earth’s elliptical orbit around the Sun showing its closest (perihelion) and farthest (apihelion) approach. (credit: timeanddate.com)
The table below shows the date/time and distances for perihelion and aphelion from 2020 to 2024.
| Year | Perihelion | Distance | Aphelion | Distance |
|---|---|---|---|---|
| 2020 | January 5, 2020 2:47 am | 91,398,199 mi | July 4, 2020 7:34 am | 94,507,635 mi |
| 2021 | January 2, 2021 8:50 am | 91,399,454 mi | July 5, 2021 6:27 pm | 94,510,886 mi |
| 2022 | January 4, 2022 1:52 am | 91,406,842 mi | July 4, 2022 3:10 am | 94,509,598 mi |
| 2023 | January 4, 2023 11:17 am | 91,403,034 mi | July 6, 2023 4:06 pm | 94,506,364 mi |
| 2024 | January 2, 2024 7:38 pm | 91,404,095 mi | July 5, 2024 1:06 am | 94,510,539 mi |
| * All aphelion/perihelion times are in EDT. | ||||
You may ask yourself: Is there any relationship between perihelion/aphelion with the solstices, since they are kind of close to one another? Well yes, they always happen close to one another. Aphelion happens about 2 weeks after the July solstice and perihelion happens about 2 weeks after the December solstice.
One of the crazy things about the extremes in Earth’s orbit around the Sun is the Sun’s apparent size in the sky. During perihelion the Sun is a little closer to us and aphelion it is a little farther from us. So this means that the Sun’s apparent size in the sky changes very slightly, i.e. when it is closer (perihelion) it appears slightly larger and when it is farther (aphelion) it appears slightly smaller. This is just perspective. These size differences are almost unnoticeable. In fact you really need a telescope to see this different. (NOTE: Do not forget to never look at the Sun with the unaided eye and especially never look at the magnified Sun with binoculars or telescopes unless you have the correct special filters!!) The composite image below, taken with a special telescope, allows us to see this subtle size difference of the Sun between perihelion and aphelion.
This composite neatly compares two pictures of the Sun taken with the same telescope and camera on the dates of Perihelion (closest approach) and Aphelion in 2008. The image labels include Earth’s distance in kilometers from the Sun on the two dates. (credit: NASA APOD/Enrique Luque Cervigón)
So happy aphelion and your farthest distance from the Sun!
