A cartoon of the Sun swinging Earth. Earth orbiting around the Sun. credit: Cartoon via Sara Zimmerman at UnEarthed Comics. (shared by Earthsky.org)
Aphelion versus Perihelion. (Orbits exaggerated). Image credit: NOAA/NASA.
Credit: http://bit.ly/1pQn7wy
This diagram shows the relation between the line of solstice and the line of apsides of Earth’s elliptical orbit. The orbital ellipse (with eccentricity exaggerated for effect) goes through each of the six Earth images, which are sequentially the points of:
However, the times of greatest solar radiation on a hemisphere happen not because of the distance between the Earth and sun but the tilt of Earth’s rotation axis. These times are during the December and June solstices.
Year | Perihelion | Distance | Aphelion | Distance |
---|---|---|---|---|
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 |
2025 | January 4, 2025 8:28 am | 91,405,993 mi | July 3, 2025 3:54 pm | 94,502,939 mi |
2026 | January 3, 2026 12:15 pm | 91,403,637 mi | July 6, 2026 1:30 pm | 94,502,962 mi |
* All aphelion/perihelion times are in local Eastern time (ET). |
Credit: Richard Jaworski, shared by Astronomy Picture of the Day
Astronomy Picture of the Day explains: “Aphelion for 2021 occurred on July 5th. That’s the point in Earth’s elliptical orbit when it is farthest from the Sun. Of course, the distance from the Sun doesn’t determine the seasons. Those are governed by the tilt of Earth’s axis of rotation, so July is still summer in the north and winter in the southern hemisphere. But it does mean that on July 5 the Sun was at its smallest apparent size when viewed from planet Earth. This composite neatly compares two pictures of the Sun, both taken with the same telescope and camera. The left half was captured close to the date of the 2021 perihelion (January 2), the closest point in Earth’s orbit. The right was recorded just before the aphelion in 2021. Otherwise difficult to notice, the change in the Sun’s apparent diameter between perihelion and aphelion amounts to a little over 3 percent.”