Autumn is a season of many changes, with some of the most notable including the dramatic multicolored displays that occur just prior to trees shedding their leaves. It’s also a time of year when many people feel reenergized by cooler temperatures and spend many hours outdoors enjoying all that fall has to offer.
Whether one is collecting leaves, picking apples, exploring corn mazes, or driving the countryside enjoying the foliage, autumn is full of fun facts that can make the season that much more enjoyable.
Autumn begins on the autumnal equinox, which occurs on or near Sept. 22 in the northern hemisphere. This year, Sept. 22 is the day when the sun crosses the celestial equator moving southward. When the equinox occurs, there are an equal number of daylight and nighttime hours.
Since ancient times, autumn has been an important time of year for many civilizations. Autumn is a main harvesting time in many areas, and a successful harvest was once necessary for survival. Many steps are, and have long been, taken to ensure a bountiful autumn harvest.
Fall is a time when trees and other plants prepare for dormancy during winter. As autumn progresses and the hours of daylight gradually decrease, trees begin to close down their food production systems and reduce the amount of chlorophyll in leaves. Chlorophyll is the chemical that makes tree leaves green, and as it declines, other chemicals become more prominent and shine through in the leaves. That is why leaves change color.
Some scientists believe that global climate change can impact autumn colors, such as delaying the change in trees. Also, red pigments may start to decline as trees use sugary fuel to grow new twigs rather than to cause red leaf displays.
Americans more readily refer to this time of year as ‘fall,’ while the British use ‘autumn.’ Both terms date back to around the 16th century. Prior to this period, autumn was known as ‘harvest.’
Much of the United States bids farewell to monarch butterflies in the fall. Each autumn, monarch butterflies migrate from the United States to Mexico and some parts of Southern California. They fly at speeds ranging between 12 and 25 miles per hour.
A study of U.S. centenarians born between 1880 to 1895 published in the Journal of Aging Research, found that babies born during autumn months are more likely to live to age 100 than those born during the rest of the year. Thirty percent of the centenarians followed were born during the fall.
Squash, pumpkins and other gourds are prominent in the fall. The largest squash grown on record belonged to Joel Jarvis of Ontario, and his huge winner weighed in at 1,486.6 pounds in 2011.
The many-colored leaves are not the only display one might see during the fall. The autumn equinox signals the aurora borealis, also called the Northern Lights. Besides the lengthening of nights and cool evening weather, which are great for stargazers, autumn is ‘aurora season,’ according to NASA. That’s because, during the fall, geomagnetic storms are about twice as frequent as the annual average.
Full moons are named for the month or season in which they rise. The Harvest Moon is the full moon closest to the autumnal equinox.