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When and What Is the Summer Solstice?

The summer solstice is the longest day of the year. Solstices are opposite on either side of the equator, so the summer solstice in the Northern Hemisphere is the winter solstice in the Southern Hemisphere, and vice versa.

The Sun shining through the Stonehenge ancient monument.

Sunrise at Stonehenge at Summer Solstice.

Some believe that Stonehenge (2500 BCE) in England was built to help establish when the summer solstice occurred.

©iStockphoto.com/AndyRoland

Northern Hemisphere Summer Solstice

(North America, Central America, Europe, Asia, Northern Africa)

June Solstice in Washington DC, District of Columbia, USA is on
Friday, June 21, 2019 at 11:54 am EDT (Change city)

June Solstice in Universal Coordinated Time is on
Friday, June 21, 2019 at 15:54 UTC

Southern Hemisphere Summer Solstice

(Australia, New Zealand, South America, Southern Africa)

December Solstice in Washington DC, District of Columbia, USA is on
Friday, December 21, 2018 at 5:23 pm EST (Change city)

December Solstice in Universal Coordinated Time is on
Friday, December 21, 2018 at 22:23 UTC

First Day of Summer?

The first day of spring, summer, fall and winter can either be defined using astronomical events like solstices and equinoxes, or they can be determined based on meteorological factors, average temperatures.

In the USA and some other areas in the Northern Hemisphere, the summer solstice marks the first day of summer. However, the official date for the first day of summer varies depending on the country's climate.

Topics: Astronomy, Seasons, December, June, Sun, Solstice

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Winter & Summer Solstices

  1. What Is the June Solstice?
  2. June Solstice Facts
  3. What Is the December Solstice?
  4. December Solstice Facts
  5. When Is the Summer Solstice?
  6. When Is the Winter Solstice?
  7. June Solstice Celebrations
  8. December Solstice Celebrations

Equinox & Solstice Worldwide


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