As June 21st approaches, the preparations for Summer Solstice for the year 2015 have geared up in the countries of Northern Hemisphere. It is the longest day of the year in terms of daylight. It also marks the beginning of summer in the Northern Hemisphere.
What is a Solstice?
The word ‘Solstice’ is derived from Latin terms sol (sun) and sistere (to stand still) as the relative position of sun in the sky at noon appears to be same during solstice and for few days following. But, during the rest of the days of the year, the position of the sun keeps changing.
A solstice is an astronomical event which is the result of change in the relative positions of the sun and the other celestial bodies. During a solstice, the sun reaches its highest or the lowest excursion, relative to the equator of the celestial body. This astronomical event is connected with seasons, as it marks the beginning of summer or winter.
The Solstice occurs twice a year!
The Sun reaches its highest or the lowest excursion, relative to the equator, twice a year – in June and December.
For an observer in the North Pole, the Sun reaches its highest position in June. On this day, the Sun reaches the northern most point of the equator. This day is also called June solstice day and marks the beginning of summer. But for the observer in South Pole, the sun will be at its lowest excursion. This day marks the beginning of winter in southern hemisphere, and hence it is called the winter solstice.
Similarly, the solstice in December will mark the beginning of winter in northern hemisphere and summer in southern hemisphere.
In 2015, solstice is on 21st June at 12:38 P.M EST and December 21, 11:48 P.M. EST.
Here is the link where you can find out the solstice time in your city!!
Solstice day is not the hottest or coldest day of the year.
Greatest portion of Earth’s surface is covered by water bodies. Water has the highest specific heat capacity. It means that it takes a while for water to get heated or cooled. Because of this, even when the sun is at its lowest point or highest point, the earth’s temperature doesn’t fall to lowest or raise to highest.
During winter solstice, the Sun’s position is at the lowest point in the sky. But the temperature doesn’t fall drastically. This is because, earth retains some summer heat which is lost gradually over the next one or two months and will reach a point where the lowest temperature is recorded. Hence, the shortest day of the year isn’t the coldest day!
The same holds good for the summer solstice. The vast water bodies on earth, which cover most of the earth’s surface, absorb the heat radiated by sun and it takes about six to eight weeks for earth’s temperature to catch up to the sun. Hence, the longest day of the year, isn’t the hottest either!
It is now, the time for celebrations in countries of northern hemisphere as summer solstice is only one day away. Countries around the world, celebrate summer solstice in their own way. Is it only the joy of celebrations or is there some science behind all of it? To find the answer, let us look at the effects of sunlight on human.
How do you feel on those dark winter days?
Do you feel the same on a bright sunny day?
The answers to these questions would make you realize the fact that sunlight lifts the spirits, gives positive energy and boosts health. Longer days and shorter nights bring several changes in the human behavior as it affects the circadian rhythm. The longer days with more sunlight is believed to affect the psychology of individuals, spread positive vibrations and is considered as an ideal time to make resolutions, strengthen relationships, start a new habit and stop bad ones.
Health benefits of sunlight
- Increases serotonin levels – lifts the mood
- Helps fight depression and stress
- Improves sleep
- Gives Vit-D, the sunshine vitamin which is needed for bone health
- Sunlight kills bad bacteria
- Lowers blood pressure, is known to cleanse blood vessels and arteries
- Strengthens immune system, increases height and helps in growth
- Known to decrease subcutaneous fat
- Electromagnetic radiations of sun is known to reduce the risk of various types of cancer
Listed above, are only few health benefits of sunlight. Modern research says there are many more ways in which sunlight may benefit human health. Our ancestors might have had a fair knowledge of these benefits. This is evident from the fact that many cultures around the world worshiped the sun and some even today.
In Indian mythology, Sun is worshiped as chief of the classical nine planets. There are temples built for sun worship, with Konark temple of Orissa, being the most famous.
Do let us know what your celebration plans are this Solstice Day.