Last night was the longest night of this year. Not only was the Moon eclipsed by the shadow of the Earth some 16 hours earlier yesterday, albeit invisibly here in Mallorca, but Winter started in the Northern Hemisphere as well. It’s cold enough everywhere in Europe to bear witness to this solar occurrence.

According to Wikipedia, “the winter solstice occurs exactly when the Earth’s axial tilt is farthest away from the sun at its maximum of 23° 26′. Though the winter solstice lasts only a moment in time, the term is also a turning point to midwinter or the first day of winter to refer to the day on which it occurs. More evident to those in high latitudes, this occurs on the shortest day, and longest night, and the sun’s daily maximum position in the sky is the lowest. The seasonal significance of the winter solstice is in the reversal of the gradual lengthening of nights and shortening of days. Depending on the shift of the calendar, the winter solstice occurs on December 21 or 22 each year in the Northern Hemisphere, and June 20 or 21 in the Southern Hemisphere. The 2010 winter solstice will occur on December 21, at 23:38 pm UTC“, i.e. last night. UTC time, by the way, is the same as Greenwich Mean Time and is one hour behind the current local time in Spain.

Strangely, Earth is now actually nearer the sun than it is in June, by about 4,500,000 kilometres. In midwinter, the Earth leans slightly on its axis by an angle off the perpendicular to the plane of orbit. Allow me to quote from candlegrove.com: “This planetary pose is what causes all the variety of our climate; all the drama and poetry of our seasons, since it determines how many hours and minutes each hemisphere receives precious sunlight.” Fascinating.

Every year since the early 17th century, the midwinter sun in Mallorca gives a spectacular performance in Palma’s cathedral, subject to weather conditions. The midwinter sun rises around 08h08 in the morning and reaches a horizontal position, allowing the sunlight to enter the cathedral’s easterly rose window in order to leave by the cathedral’s westerly roseton, thus illuminating the cathedral’s interior with the most beautiful exhibit of light. The cathedral is not open at that time of day and you wouldn’t see the striking effect from inside the temple anyway. The best place to watch would be from the terraces of the Baluard de Sant Pere (now the Baluard Museu d’Art Modern i Contemporary). The Societat Balear de Matemàtiques (Mathematical Society) organised a visit to see the sun perform its magic last Sunday but, heavy clouds interfered with any visibility of the sun at that early hour. Likewise, I doubt that the sun could penetrate the clouds earlier this morning. Saturday, December 25th, may offer another chance to clearly see the sun of the Winter Solstice do its alluring show in and out of Palma’s La Seu cathedral. Let’s hope that we can witness the beautiful solar attraction, then.

The photos were borrowed from the Internet, courtesy of xeix.org. The photo (top) was taken in Palma de Mallorca, Baleares, Spain. The date: December 4th, 2008. The time was 08:16:53. The photo (bottom) was taken in Palma de Mallorca, Baleares, Spain. The date: December 18th, 2010.

Moltes gràcies.