THE SUN IN THE SKY Astronomical terms and tidbits

Meaning: The word solstice means “standing still sun.” Other references include litha, midsummer and St. John’s Feast, which marks the nativity of St. John the Baptist.

Summer solstice: An astronomical term for the moment when one hemisphere of the Earth is tilted the most toward the sun. Today, the sun is about 231⁄2 degrees above the celestial equator — its highest point of the year. In the Northern Hemisphere, the date is usually June 21 or 22. The day also has the longest period of daylight and the shortest of night; this occurs around six months from now for the Southern Hemisphere.

Winter solstice: Historically known as midwinter and occurs Dec. 21 or 22 in the Northern Hemisphere. It is the shortest day and longest night of the year and marks the astronomical beginning of winter.

Spring equinox: The first day of spring, March 20 or 21. In the Northern Hemisphere, the sun crosses the equator and moves northward. It is the beginning of a long period of sunlight at the pole. Day and night are of about equal length.

Autumn equinox: The first day of autumn, Sept. 22 or 23. In the Northern Hemisphere, the sun crosses the equator and moves southward. Day and night are of about equal length.

Ancient history: Many ancient cultures built important architecture — tombs, temples and observatories — so that they are aligned with solstices and equinoxes. Stonehenge in England is a perfect marker for solstices. The Druids saw the solstice as the wedding of heaven and earth.

On the calendar: Some solstice celebrations still center on June 24, which no longer is the longest day of the year. The difference between the Julian calendar year (365.2500 days) and the tropical year (365.2422 days) moved the day associated with the astronomical solstice forward about three days every four centuries until Pope Gregory XIII changed the calendar, bringing the solstice to June 21. The evening of June 23 is St. John’s Eve, the time before the celebration of the Feast Day of St. John the Baptist. This event coincides with the summer solstice, which technically can be from June 20-26. St. Patrick Church, 1420 Oak Hill, Youngstown, plans a St. John the Baptist bonfire celebration from 6:30 to 8:30 p.m. Sunday with food, music, crafts and children’s activities. A bonfire is a traditional element of midsummer observances in France, Portugal, Denmark, Lithuania, Finland, Germany and the United Kingdom.