• Autumn has been called the “hectic beauty of death.”
  • Levels of testosterone in both men and women are at their highest in the fall. Scientists speculate the surge may be a result of ancient mating instincts (e.g., the fall “rutting season”) or that decreasing daylight somehow triggers it.
  • Since ancient times, autumn has ranked as one of the most important times of year as daylight begins to fade and cold, dark days lie ahead. Because a good harvest is necessary for survival, many societies tried to ensure a good harvest by honoring various gods and goddesses. Some societies, such as the Aztecs in ancient Mexico, even made human sacrifices to please the gods.
  • autumn
  • According to NASA, autumn is “aurora season” because geomagnetic storms are about twice as frequent as the annual average during the fall.
  • A “Harvest Moon” is the full moon closest to the autumn equinox. Before artificial lighting, such moonlight was essential to a farmer’s successful harvest.
  • During the fall, in response to colder temperatures and less light, leaves stop producing chlorophyll, the green pigment that helps capture sunlight to power photosynthesis. As the green fades, the leave’s other pigments shine through, such as orange and yellow carotenoids and vibrant red anthocyanin.
  • Scientists believe global warming could affect autumn colors. As the world warms, leaves may delay changing their colors. Additionally, trees may not use their sugars to create red pigments; rather, they might send that fuel to growing new twigs. Global warming may also alter the habitats of trees, such as the sugar maple, which creates some of the most vibrant fall colors.
  • Animals and plants respond to the light changes associated with autumn. For example, each autumn, the male Siberian hamster’s testes swell up to 17 times bigger than normal to prepare for mating.
  • Each fall, the black-capped chickadee’s tiny hippocampus enlarges by 30%, which enables it to remember where it collected seeds in different spots in trees and on the ground.
  • Researchers found that during the cooler months of autumn, men are more likely to cozy up with their sweethearts and watch romantic comedies. Feeling cold activates a yearning for warmth and comfort with others.
  • The autumnal equinox occurs on different dates each year, but usually falls on September 22 or 23. In 1931, the equinox fell on September 24 because the Gregorian calendar doesn’t always match up with the position of Earth in its orbit around the sun. The fall equinox won’t happen again on September 24 until 2303.
  • The term “equinox” is from the Latin meaning “equal night.”
  • Solstices and equinoxes are solar events that have to do with Earth’s position in relation to the sun at different times of the year. Solstices (summer and winter) are when the sun is at its northernmost or southernmost position in the sky. The equinox (fall and spring) is when day and night are (roughly) the same length all over the world.
  • Autumn begins when the center of the sun crosses Earth’s equator. As Earth continues its path around the sun, days become shorter and nights become longer, with the change most noticeable for those at higher latitudes.
  • Many birds prepare for winter migration during the fall. One of the longest migrations is the 11,000-mile journey by the Arctic Tern.
  • While Americans typically use the word “fall,” the British use the word “autumn,” though both terms date around the 16th century. Before these terms, the period was called “harvest.”