Just a few hours ago (11:49 p.m. EDT March 19 or 0349 GMT March 20, 2020) spring arrived in the Northern Hemisphere. Officially it is spring, even though it may not feel like it where you live.
For the next three months, the days will continue to get longer as the Sun moves farther north. This year, the Sun reaches its greatest northern latitude on June 20 when it will be at its highest elevation in the Northern Hemisphere sky. In the Southern Hemisphere, it will be at its lowest elevation. The autumn equinox will arrive on September 22. Then, on December 21, the Southern Hemisphere will have the Sun directly overhead at 23 degrees south latitude while it will be at the lowest point in the north.
At Chichen Itza on the Yucatan Penninsula of Mexico, the Mayans built a huge pyramid to a serpent deity around A.D. 1000. They engineered the pyramid so that at the spring equinox, the Sun’s light resembles a huge snake slithering down the steps on the structure’s face. The Mayans called the equinox “the return of the Sun Serpent.” They recognized the reliable and consistent seasons that make life possible. They could not comprehend everything required to create that consistent reliability. They didn’t know the God who created all things.
Scientists today use SETI to search for intelligent life elsewhere in the universe. They use telescopes and space probes to look for an exoplanet suitable for life. So far, after millions of hours and unknown amounts of money spent searching for alien life, the results have been zero.
The orbit of the Earth around the Sun produces variations in the seasons with four orbital positions having particular significance. Today, March 19, 2020, the Sun will pass directly overhead at the equator. The exact time will be 11:49 p.m. EDT (0349 GMT March 20, 2020). We can rejoice that the vernal equinox arrives today!
This is the earliest equinox in the United States in 124 years! As you can see in the diagram, the usual date for the vernal equinox is March 20 or 21, depending on where you live on the Earth. The reason it arrives on the 19th this year in North America is somewhat complicated, but it has to do with leap years and daylight saving time. We won’t get into that, but I thought we should explain why the diagram differs from this year’s dates.
There is wonderful history of how the Greek scholar Eratosthenes of Alexandria used the equinox to measure the circumference of the Earth. He knew that on the equinox, a pole stuck vertically in the ground left little or no shadow at noon, depending on location. He compared the length of the shadow of a pole in Syene, a town in southern Egypt, with one in Alexandria in northern Egypt. Using the difference in the shadow lengths, he calculated the circumference of the Earth. His calculation was very close to the known circumference today, and it proved the Earth was round. He did that in 245 BC, long before Columbus sailed.
The four polar positions roughly predict the seasons that have been used by every culture to control planting, harvesting, and preparing the soil. In Genesis 1:14, God said, “Let there be lights in the expanse of space to divide the day from the night, and let them be for signs, and for seasons, and for days, and years.” God not only instituted day and night, but He also positioned the Sun and Moon so they could be used to mark the seasons we would need to live on this planet.
As the vernal equinox arrives today, we wish you a happy equinox!!Enjoy the season and the official end of winter in the Northern Hemisphere. We will have more on the spring equinox tomorrow.
Today, March 20, 2019, is a special day as the spring equinox arrives for the Northern Hemisphere. Today the Sun will set exactly in the west and tomorrow it will rise exactly in the east when observed from the Equator. The day will be exactly 12 hours long and night will be exactly 12 hours long. After today in the Northern Hemisphere, the days will be longer than the nights. Officially spring arrives today at 9:58 PM Greenwich Mean Time (5:58 PM Eastern Daylight Time where we live).
In reality, all of this is an exaggeration of the real situation.Don’t expect a balmy spring day if you live in Michigan (as we do) or other northern areas. Ice and snow have to melt, and the land has to warm up. Nevertheless, the equinox does remind us of Earth’s design and how many variables control our existence on this planet. What does happen on this day is that the Sun will be directly overhead at noon at the equator.
During the northern winter, Earth’s tilt has caused the Sun to be overhead south of the Equator. As the Earth moves around the Sun, the Sun’s location relative our planet will drift north until June. When the summer solstice occurs on June 21, the Sun will be overhead at 23 degrees north latitude. The more direct sunlight not only warms the Northern Hemisphere, but it avoids overheating the Southern Hemisphere.
If Earth did not have a 23-degree axis tilt, the Sun would beat down on the equator from directly overhead all year long. The Equator would become so hot that nothing could live there. The northern and southern latitudes would both freeze. Wind belts created by air rising violently at the equator would be hurricane force 24/7. We see that happening on planets in the solar system that do not have an axis tilt.
Ancient people knew that the position of the Sun changes throughout the year. They used elaborate but primitive observatories to determine the time to plant and harvest based on the Sun’s position. Unfortunately, this led many cultures to worship the Sun. Nowhere does the Bible encourage or condone the worship of any celestial bodies. The Bible recognizes the seasons and the role of the Sun as designed by God for human existence. (See Genesis 1:14-15).
The ancient psalmist David said it (Psalms 8:4) and the writer of Hebrews quoted it (Hebrews 2:6), “What is man that you keep him in mind or the son of man that you look after him?” The equinox is a good time to be reminded of God’s provisions for us and thankfully worship the Creator, not the creation.
We have just passed the autumn equinox and what we call “the first day of fall.” It will be late December before fall officially ends at the winter solstice. On the first day of fall here in Michigan, it was unseasonably hot, and people were griping about “where is the cool fall weather we are supposed to have?” Long before the first day of winter on December 20-21, we will have snow. Is there something wrong with the seasons, or is the trouble with our understanding?
“Equinox” suggests that the length of the day is equal to the length of the night. The Sun is overhead at the equator, and from now until December 20 it will be directly overhead at progressively greater southern latitudes until it reaches just past 23 degrees south latitude. Here in the north, the Sun’s elevation above the horizon will get progressively lower, meaning that less and less of the Sun’s energy will strike the Earth’s surface so the weather will get cooler.
The problem with this simple picture is that there is a lag in the seasons. During the summer months in the Northern Hemisphere the lakes and oceans warm from the sunshine. Water has a high specific heat, so that heat is stored and is released slowly. That means we stay warm longer than expected in the fall. In the Southern Hemisphere the picture is complicated by the fact that the Earth is closer to the Sun during their summertime, so the radiation is more intense. That might be a problem except that the Southern Hemisphere has more water than the Northern Hemisphere because oceans cover more of the southern Earth’s surface. With that greater storage and absorption capacity moderates the temperatures in the Southern Hemisphere.