The Northern Hemisphere will officially experience the first day of summer and the longest day of the year with the beginning of solstice this week. Conversely, those in the Southern Hemisphere can welcome the start of winter.

The solstice marks the transition of the seasons that Northern and Southern Hemispheres will experience. During this time, Earth’s axis will slightly shift with its northern axis tilting a little bit closer to the Sun. As a result, the Northern Hemisphere will experience more sunlight as well as a warmer temperature. The southern axis, on the other hand, will tilt farther away from the Sun.

This year’s summer solstice will officially begin on June 21. It will occur in the Southern Hemisphere at 3:54 pm UTC and 10:54 am CDT for those in the Northern Hemisphere, according to Earth Sky.

For ancient civilizations, the summer solstice was a significant yearly event because it was closely related to their daily practices and traditions.  

“The significance of the summer solstice to ancient cultures had many aspects, including calendaring, crop planting and agriculture, moving their camp or housing location for nomadic peoples, and annual cultural ceremonies, professor Aparna Venkatesan of the University of San Francisco said according to NBC Washington.

In modern times, the solstice is welcomed by different countries to celebrate the transition between seasons. California, for example, hosts a three-day festival in the city of Santa Barbara to celebrate the star of summer. The event features a mixture of music, parades and outdoor parties.

Aside from the momentous transition between the seasons, sky gazers will also be treated to the appearance of a couple of cosmic bodies within the next couple of days.

Currently, the most prominent planets that can be spotted from Earth are Mercury and Mars. Within the next few days, Mercury will be moving farther away from the Sun, making it easier to spot. It will reach its maximum distance from the Sun on June 23, National Geographic reported.

Just about a degree to the right of Mercury is Mars. Located above these two planets are the stars Castor and Pollux.

Summer Solstice People celebrate the summer solstice at the Kokino megalithic observatory, near the city of Kumanovo, Macedonia, June 21, 2016. Photo: REUTERS/Ognen Teofilvovski