Perihelion and Aphelion: When Earth Is Closest to and Farthest From the Sun
Earth is closest to the Sun around January 3, in the middle of northern winter. The distance changes by only about 3 percent, so tilt, not distance, makes the seasons.
Try it in the instrument
Set the sky to the date of Earth’s closest approach to the Sun.
Also called
apsides, closest point to the Sun, farthest point from the Sun
A simplified model
The drawings are computed from the numbers in the sources. They simplify the real sky. For exact times and dates, use official tables.
Earth does not circle the Sun at a fixed distance. Once a year it swings closest, and half a year later it is farthest. It is easy to guess that the closest point must fall in summer. It does not. It falls in early January, in the middle of the northern winter.
This guide gives the two terms, the official 2026 dates and the distances, and explains why distance is not what makes the seasons. It ends with a task in the Orbit Dial: finding the date of Earth's closest approach to the Sun.
What the two words mean
The U.S. Naval Observatory's glossary defines perihelion as the point in an orbit that is nearest to the Sun, and aphelion as the point that is most distant from the Sun. Together they are called the apsides of the orbit. NASA's Space Place uses plain words for the same thing: the point closest to the Sun and the point farthest from it.
The Naval Observatory measures the distance from the center of the Sun to the center of Earth. So perihelion and aphelion are not places you can see from the ground. They are moments in the year when that center-to-center distance is at its smallest and its largest.
The 2026 dates
The Naval Observatory's seasons and apsides service lists these events for 2026. Times are in Universal Time, the time at Greenwich.
| Event | Date in 2026 | Time (Universal Time) |
|---|---|---|
| Perihelion | January 3 | 17:15 |
| March equinox | March 20 | 14:46 |
| June solstice | June 21 | 08:24 |
| Aphelion | July 6 | 17:30 |
| September equinox | September 23 | 00:05 |
| December solstice | December 21 | 20:50 |
Convert the time to your own zone before you mark a calendar. The Naval Observatory gives U.S. Eastern Standard Time as 5 hours behind Universal Time, so perihelion falls at 12:15 p.m. there.
The same service covers every year from 1700 to 2100. Enter a year and it returns the date and time of each event, so you can check any year you like.
The table also shows how the apsides sit against the seasons. Perihelion comes about two weeks after the December solstice, as the Naval Observatory says. Aphelion in 2026 comes 15 days after the June solstice.
How far away is the Sun?
NASA's planetary fact sheets give the two extremes. NASA's Earth page and the National Weather Service give the average, about 93 million miles.
| Point | Distance from the Sun | In kilometers |
|---|---|---|
| Perihelion | 91.4 million miles | 147.1 million |
| Average | About 93 million miles | About 150 million |
| Aphelion | 94.5 million miles | 152.1 million |
The National Weather Service describes the same swing from the average: about 1.6 million miles closer in early January and about 1.6 million miles farther in early July. The Naval Observatory sums it up as a percentage. The distance to the Sun at perihelion is only about 3 percent less than at aphelion.
NASA lists Earth's orbital eccentricity as 0.0167. Eccentricity measures how stretched an orbit is, and zero would be a perfect circle. Earth's orbit is therefore close to a circle.
Use this check list for 2026:
- Closest point: January 3, 17:15 Universal Time, at 91.4 million miles (147.1 million kilometers).
- Farthest point: July 6, 17:30 Universal Time, at 94.5 million miles (152.1 million kilometers).
- Size of the swing: about 3 percent, according to the Naval Observatory.
- Cause of the seasons: the 23.4 degree tilt of Earth's axis, not the distance.
Why it happens in the northern winter
The surprise is the timing. In January the Northern Hemisphere has winter, and Earth is at its closest. NASA's Space Place points out exactly that: the north has winter when Earth is nearest the Sun, so distance cannot be the cause of the seasons.
The Naval Observatory names the real cause: the seasons come from the 23.4 degree tilt of Earth's axis. It says the effect of distance is too weak to cause the seasons, though it might have some influence over their severity. NASA adds that the change in distance does not make much difference to our weather.
The seasons are reversed in the Southern Hemisphere, as the Naval Observatory notes. So the south has summer in January, when Earth is nearest the Sun. The guide on the axial tilt shows how the tilt does the work, and the guide on the winter solstice covers the shortest day, which comes just before perihelion.
Why the dates move
The dates are not the same every year. The Naval Observatory explains that Earth and the Moon both orbit, once a month, around a shared point called the Earth-Moon barycenter. On average that point sits about 4,700 kilometers (2,900 miles) from Earth's center. Where Earth is in that monthly loop shifts the moment of perihelion and aphelion.
The Moon's position does not repeat on the same date from year to year. The result looks quasi-random, in the Naval Observatory's words. That is why 2026 has its aphelion on July 6, in the first week of July but not on a fixed day.
There is also a slow drift. The Naval Observatory says the date of perihelion moves later within the year by about one full day every 58 years. One reason is that the time from one perihelion to the next, called the anomalistic year, averages about 25 minutes longer than the tropical year from equinox to equinox.
Common mistakes
- Thinking summer means Earth is closer. Perihelion falls in the northern winter, and aphelion falls in the northern summer.
- Picturing a long, stretched oval. The distance changes by about 3 percent, and the eccentricity is 0.0167.
- Expecting the same date every year. The Moon pulls Earth around the barycenter, so the dates wander by a day or two. Use the year's table, not a memory.
- Reading Universal Time as local time. The Naval Observatory's 17:15 on January 3 is 12:15 p.m. in U.S. Eastern Standard Time.
- Confusing the words. Perihelion is the nearest point. Aphelion is the most distant one.
- Blaming distance for the weather. NASA and the Naval Observatory both say distance is not the cause of the seasons.
Try it in the instrument
Open the Orbit Dial and set the sky to the date of Earth's closest approach to the Sun. The dial takes a date in 2026 and a latitude, then shows the Sun's height at noon and the length of the day.
Set the date to January 3, 2026. That is the perihelion date in the Naval Observatory's table, at 17:15 Universal Time. The real date shifts from year to year, so a window of a day or two around January 3 is the sensible target.
Then look at the readouts and notice the surprise. At 49° N, the Naval Observatory lists 8 h 21 min of daylight on January 3, close to its winter low of 8 h 14 min. In the north, the closest day of the year looks like winter. If the dial prints a distance, compare it with NASA's 91.4 million miles (147.1 million kilometers), and allow for small differences, because the dial is a simplified model.
Questions people ask
When is Earth closest to the Sun in 2026?
On January 3, 2026, at 17:15 Universal Time, according to the U.S. Naval Observatory. Aphelion follows on July 6 at 17:30.
How far is Earth from the Sun at perihelion?
About 91.4 million miles (147.1 million kilometers), according to NASA. At aphelion it is about 94.5 million miles (152.1 million kilometers).
Does being closer make winter warmer?
Not much. The Naval Observatory says distance is too weak to cause the seasons, though it might influence their severity. NASA says the change does not make much difference to weather.
Why is perihelion not on the same date every year?
Earth and the Moon orbit a shared point, and the Moon's position does not repeat on the same date each year. That moves the moment of closest approach by a day or two.
Is Earth farthest from the Sun in summer?
In the Northern Hemisphere, yes. Aphelion falls in early July, which is 15 days after the June solstice in 2026.
Sources
- Earth's Seasons - Equinoxes, Solstices, Perihelion, and Aphelion, U.S. Naval Observatory. https://aa.usno.navy.mil/data/Earth_Seasons. Opened November 10, 2026.
- Glossary, U.S. Naval Observatory. https://aa.usno.navy.mil/faq/asa_glossary. Opened November 10, 2026.
- Variation in Times of Perihelion and Aphelion, U.S. Naval Observatory. https://aa.usno.navy.mil/faq/apsides. Opened November 10, 2026.
- The Seasons and the Earth's Orbit, U.S. Naval Observatory. https://aa.usno.navy.mil/faq/seasons_orbit. Opened November 10, 2026.
- Duration of Daylight/Darkness Table for One Year, U.S. Naval Observatory. https://aa.usno.navy.mil/data/Dur_OneYear. Opened November 10, 2026.
- Earth Fact Sheet, NASA Space Science Data Coordinated Archive (NSSDCA). https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html. Opened November 10, 2026.
- Planetary Fact Sheet - U.S. Units, NASA Space Science Data Coordinated Archive (NSSDCA). https://nssdc.gsfc.nasa.gov/planetary/factsheet/planet_table_british.html. Opened November 10, 2026.
- What Causes the Seasons? | NASA Space Place – NASA Science for Kids, NASA Space Place. https://spaceplace.nasa.gov/seasons/en/. Opened November 10, 2026.
- Facts About Earth, NASA Science. https://science.nasa.gov/earth/facts/. Opened November 10, 2026.
- The Astronomical Seasons Page, National Weather Service, Tucson. https://www.weather.gov/twc/Astronomical_Seasons. Opened November 10, 2026.
We opened each source ourselves on the date shown. The drawings are our own and were checked against the numbers in these sources.
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