March Night Sky
Sky events for this month & objects for observation can be found here.
Courtesy of Orion Telescopes & Binoculars
Click to enlarge. A larger printable version of this chart can also be found here.
MOST NAKED EYE PLANETS GATHER IN MORNING SKY
The planets Mercury, Venus, Jupiter, and Saturn appear to the west of the Sun in the morning sky for most of the month of March. In the chart above for mid-March, the colored arrows show the motion of each planet and the Sun during the month. The Moon is plotted for the evening dates in the Americas when it's waxing (right side Illuminated) or full, and for the morning dates when it's waning (left side illuminated). Sky & Telescope.
The Vernal Equinox Arrives
The March or vernal equinox signals the start of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. The equinox is a hallmark of the seasons. At this equinox, the Sun crosses the celestial equator moving from south to north. The March 2021 equinox falls on March 20 at 09:37 UTC. That’s 02:37 a.m. Pacific Daylight Time for us in the Pacific Northwest. The equinoxes and solstices are caused by Earth’s 23.5 degree tilt on its axis and ceaseless motion in orbit around the Sun.
The March or vernal equinox signals the start of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. The equinox is a hallmark of the seasons. At this equinox, the Sun crosses the celestial equator moving from south to north. The March 2021 equinox falls on March 20 at 09:37 UTC. That’s 02:37 a.m. Pacific Daylight Time for us in the Pacific Northwest. The equinoxes and solstices are caused by Earth’s 23.5 degree tilt on its axis and ceaseless motion in orbit around the Sun.
The tilt of the Earth axis creates the changes in solar altitude in the sky and results in the seasons.
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Change in the length of day due to the Earth's tilt in relation to its orbit around the Sun.
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At the equinox, Earth’s two hemispheres are receiving the sun’s rays equally. Night and day are often said to be equal in length. In fact, the word equinox comes from the Latin aequus (equal) and nox (night). For our ancestors, whose timekeeping was less precise than ours, they likely did seem equal. But now we know it’s not exactly so. Due to atmospheric refraction, and because the Sun is a very close star and has a disc rather than being a point of light, on the day of the equinox the day is slightly longer than the night from sunrise to sunset. Morning and evening twilight makes this even a little longer for full darkness to arrive.
Equilux is the word is used to describe the day on which day and night are equal. The equilux happens a few to several days before the spring equinox, and a few to several days after the autumn equinox. Much as earliest sunrises and latest sunsets vary with latitude, so the exact date of an equilux varies with latitude. That’s in contrast to the equinox itself, which is a whole-Earth event, happening at the same instant worldwide.
Another fact is that the Sun rises exactly due east and sets due west at the equinox. And that’s the case no matter where you live on Earth. If your local streets are laid out east and west, diving can be more hazardous with the glare of the Sun blinding you near sunrise and sunset. At the equinoxes, the Sun appears directly overhead at noon as seen from Earth’s equator. No matter where you are on Earth – except at the Earth’s North and South Poles – you have a due east and due west point on your horizon. That point marks the intersection of your horizon with the celestial equator – the imaginary line above the true equator of the Earth.
In the Northern Hemisphere, the March equinox will bring earlier sunrises, later sunsets, softer winds, and sprouting plants. Meanwhile, you’ll find the opposite season – later sunrises, earlier sunset, chillier winds, dry and falling leaves – south of the equator. Where can you look to see signs of the equinox in nature? Everywhere! Forget about the weather for a moment, and think only about the daylight. In terms of daylight, the knowledge that spring is here – and summer is coming – permeates the northern half of Earth’s globe. The arc of the Sun across the sky each day is shifting toward the north. Responding to the change in the length off day, birds and butterflies are migrating back northward, along with the path of the Sun. The longer days in the northern hemisphere bring with them warmer weather, and people are leaving their winter coats at home. Trees are budding, and plants are beginning a new cycle of growth. In many places, spring flowers are beginning to bloom.
Equilux is the word is used to describe the day on which day and night are equal. The equilux happens a few to several days before the spring equinox, and a few to several days after the autumn equinox. Much as earliest sunrises and latest sunsets vary with latitude, so the exact date of an equilux varies with latitude. That’s in contrast to the equinox itself, which is a whole-Earth event, happening at the same instant worldwide.
Another fact is that the Sun rises exactly due east and sets due west at the equinox. And that’s the case no matter where you live on Earth. If your local streets are laid out east and west, diving can be more hazardous with the glare of the Sun blinding you near sunrise and sunset. At the equinoxes, the Sun appears directly overhead at noon as seen from Earth’s equator. No matter where you are on Earth – except at the Earth’s North and South Poles – you have a due east and due west point on your horizon. That point marks the intersection of your horizon with the celestial equator – the imaginary line above the true equator of the Earth.
In the Northern Hemisphere, the March equinox will bring earlier sunrises, later sunsets, softer winds, and sprouting plants. Meanwhile, you’ll find the opposite season – later sunrises, earlier sunset, chillier winds, dry and falling leaves – south of the equator. Where can you look to see signs of the equinox in nature? Everywhere! Forget about the weather for a moment, and think only about the daylight. In terms of daylight, the knowledge that spring is here – and summer is coming – permeates the northern half of Earth’s globe. The arc of the Sun across the sky each day is shifting toward the north. Responding to the change in the length off day, birds and butterflies are migrating back northward, along with the path of the Sun. The longer days in the northern hemisphere bring with them warmer weather, and people are leaving their winter coats at home. Trees are budding, and plants are beginning a new cycle of growth. In many places, spring flowers are beginning to bloom.
Spring Equinox Traditions
Cultures and countries around the world mark spring equinox with various holidays. Here are a few of them:
Nowruz (Persian New Year): This is one of humanity's oldest celebrations, going back thousands of years. Nowruz is a word in the Farsi language of Iran, and it means new day. The United Nations says more than 300 million people celebrate Nowruz. This includes Iran as well as places that have felt Persian influence through the ages: the Balkans, the Black Sea Basin, the Caucasus, Central Asia and the Middle East. Despite the tradition predating the rise of Islam by many centuries, it's a national holiday in the Islamic Republic of Iran.
Vernal Equinox Day: On the other side of Asia from Iran is another country with a public holiday: Japan. The holiday has its roots in the ancient Shintoism religion. Adherents believed that every natural object possessed a spiritual force. During spring, trees and flowers thrive, so eventually the vernal equinox became the official day for celebrating.
The holiday is now a secular one. To celebrate, people will hold family reunions, visit shrines and seek out cherry blossoms and other natural wonders.
Holi: Yet another Asian religion -- Hinduism -- has an arrival-of-spring holiday. Holi is a very old festival. The first known mention of it is in a fourth century poem.
It's a national holiday in India, and it is celebrated on the day after the full moon in the Hindu month of Phalguna. It's not a uniform holiday -- the start and end dates can vary by region and the duration of the celebration can be different, too. For many Indians in 2019, Holi will start on Wednesday, March 20, and end the next day.
For many Westerners, the holiday is known for the vibrantly colored powders with which people cover themselves and others.
Easter: It's no coincidence that Christians around the world celebrate the resurrection of Jesus around the same time that spring brings a rebirth to nature (in the temperate zones of the Northern Hemisphere, at any rate). The date of each Easter is set on the first Sunday after the full moon that occurs on or after the spring equinox. That allows Easter to fall anywhere from March 22 to April 25.
Ancient Sites and Gatherings
Our ancestors had a keen awareness of the seasons and the movements of the sun and other stars. They built mysterious sites that have at least one obvious use: that of giant calendars, often aligned to prominently display shafts of sunlight during solstices and equinoxes.
Here are just a few of them:
Chichen Itza, Mexico: This complex of Mayan ruins on the Yucatan Peninsula of Mexico is popular all year but especially during the spring and autumn equinoxes.
At the "El Castillo" pyramid dedicated to Kukulcán (or Quetzalcoatl), the late afternoon sun creates the shadow illusion of a snake slowly sliding down the northern staircase. Thousands come here to witness this spectacle, and the day now has a carnival atmosphere, with music, dancers and more.
Mnajdra Temples, Malta: On the Mediterranean island of Malta, the Mnajdra complex consists of three temples. The buildings are estimated to date from 3600 B.C. to 2500 B.C.
During the spring and fall equinoxes, the rising sun is in exact alignment with the main doorway of the lower temple, which allows sunlight to fill the main corridor into the innermost altar. It's a celebrated event on the island.
Stonehenge, England: The most famous Neolithic structure in England if not the world is the gathering place for pagans, druids and the plain curious during spring equinox. You can arrange a tour during either of the equinoxes or solstices and watch the same awe-inspiring, clockwork sunrise that our ancient ancestors witnessed thousands of years ago.
Stonehenge - Salisbury Plain in Wiltshire, England.
