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Earth's Seasons - Equinoxes, Solstices, Perihelion, and Aphelion

This data service provides the dates and times of the seasons ( equinoxes and solstices ) and apsides ( perihelion and aphelion ) of the orbit of the Earth for the years 1700 - 2100. Just type the year of interest in the space below and click on the "Get Data" button.

Year For example: 1986

Time Zone Example: 5 hours West of Greenwich (UTC-5) is Eastern Standard Time
Need a time zone?  Try the time zone map.

Account for US Daylight Saving Time? No Yes

Notes

The times of the equinoxes mark the beginning of spring and fall. The times of the solstices mark the beginning of summer and winter.

The seasons are hemisphere dependent. While the northern hemisphere experiences summer, the southern hemisphere is experiencing winter. That said, the conventional method for naming the solstices and equinoxes is by the seasons of the northern hemisphere. Therefore, the equinox in March is referred to as the Spring Equinox even though Fall is happening in the southern hemisphere.

The page on Variation in Times of Perihelion and Aphelion explains why the times of apsides appear to vary more than those of the seasons. The page on The Seasons and the Earth's Orbit discusses how all of these phenomena relate.

Time Zones

When using the "Need a US Time Zone" button, the service will fill the Time Zone hours field and set the Time Zone direction button according to the standard US time zone entered.

For locations that require it, you may enter the time zone in decimal hours. For example, for locations in India, you may enter 5.5 hours east of Greenwich for the time zone. The time zone field can accommodate up to five characters.

Daylight Saving Time

This service implements US daylight saving time (DST) rules for dates from 1967 through the present day in accordance with the Uniform Time Act of 1966 and subsequent legislation. If you set the "Account for US Daylight Saving Time" radio button on, the results will include a 1 hour offset to the given Time Zone hour if the requested date occurs during a DST period.

Application Programming Interface

This data service uses one of our Application Programming Interfaces (APIs). The API returns data in JavaScript Object Notation (JSON) format for users who wish to manipulate data into a customized format. For more information on the API, please see the documentation page.