Seattle Gains 11 Extra Minutes of Daylight During Spring Equinox The spring equinox occurred at 7:46 a.m. PDT on Friday, marking the start of longer days for the northern hemisphere. While the idea that balancing an egg on its end is only possible during the equinox is a myth, the event does signal the beginning of the brightest six months of the year. The equinox happens twice annually when the sun’s rays strike the equator at a right angle, creating nearly equal periods of daylight and darkness. This occurs because Earth’s tilted axis causes the sun’s direct rays to cross the equator from south to north during the spring equinox, allowing the northern hemisphere to receive more sunlight for six months. The term “equinox” comes from Latin, meaning “equal night,” though in Seattle, the day is actually 12 minutes longer than 12 hours. This discrepancy arises due to atmospheric refraction, which bends sunlight and extends the visible daylight. A day with precisely 12 hours of daylight is called the equilux, which in Seattle coincided with St. Patrick’s Day. While the equinox itself doesn’t guarantee perfect day-night balance, it sets the stage for the gradual increase in daylight as spring progresses. As the season transitions, residents are encouraged to embrace the changing light and enjoy the extended hours of sunlight.#seattle #st_patrick_s_day #spring_equinox #equilux #atmospheric_refraction
A not-so-equal equinox: Why day beats night on the 1st day of spring The spring equinox marks the first day of spring today, but daylight actually lasts several minutes longer than night. Here's why the equinox doesn't appear perfectly equal. On March 20 at 10:46 a.m. Eastern Daylight Time, the vernal equinox occurs. At that moment, the sun aligns directly over the equator, casting equal light on both hemispheres. However, this moment is not the exact midpoint of day and night. For North Americans, spring officially begins on March 20, a shift from the traditional March 21. This change is due to the Earth’s elliptical orbit and the structure of the Gregorian calendar. From 1980 to 2102, the equinox will never fall later than March 20. In 2028, it will even occur on March 19 for the Western Hemisphere. The idea that days and nights are equal on the equinox is a common misconception. In reality, daylight is longer than darkness by several minutes. For example, in Pittsburgh, the equinox does not mark equal day and night but rather Saint Patrick’s Day. This discrepancy arises because sunrise and sunset times are calculated based on when the sun’s top edge appears on the horizon, not its center. The sun’s apparent diameter, about half a degree, contributes to this effect. Additionally, Earth’s atmosphere bends sunlight, creating an optical illusion. The U.S. Naval Observatory accounts for this refraction, noting that the sun’s geometric center is more than eight-tenths of a degree below the horizon at sunrise. As a result, we see the sun for a few minutes before it rises and after it sets. This atmospheric lens effect adds approximately six to seven minutes to daylight each day.#us_naval_observatory #pittsburgh #spring_equinox #earth_elliptical_orbit #joe_rao
Spring Equinox Marks the Start of Astronomical Spring The spring equinox is approaching and signals the beginning of astronomical spring in the northern hemisphere. This year, the event will occur on 20 March at 14:45, marking the moment when the Earth’s axis is tilted neither toward nor away from the Sun. This alignment results in nearly equal daylight and darkness across the globe, though the exact timing of equal day and night varies slightly due to atmospheric refraction. The equinox happens twice annually, once in March and once in September, and is determined by the Earth’s axial tilt of 23.5 degrees. As the planet orbits the Sun, this tilt shifts, leading to seasonal changes. During the equinox, sunlight is distributed equally between the northern and southern hemispheres. For regions south of the equator, the event heralds the start of autumn. The term "equinox" originates from Latin, combining "equi" (equal) and "nox" (night). While the equinox is often associated with equal day and night, this is not entirely accurate. In the UK, the actual day when daylight and darkness are precisely balanced occurs a few days earlier, on 18 March, known as the equilux. This discrepancy arises because the Sun’s position is measured from its center, and atmospheric refraction extends daylight beyond the moment the Sun disappears below the horizon. Astronomical spring officially begins on the equinox, whereas meteorological spring, used by weather forecasters, starts on 1 March. This distinction allows for more consistent annual comparisons of weather patterns. The months of March, April, and May are considered spring in the meteorological calendar, but the equinox marks the start of the astronomical season.#spring_equinox #earth_axis #sunlight_distribution #equilux #meteorological_spring
Easter's Floating Date Explained: 2026 Celebration and Traditions Easter is not fixed on a specific calendar date, unlike holidays such as Christmas on December 25 or Independence Day on July 4. Instead, it moves between late March and mid-April, always falling on a Sunday. The date is determined by a combination of astronomical and religious calculations. Specifically, Easter is set for the first Sunday following the first full moon after the spring equinox, which occurs on March 20. For 2026, this will place Easter on April 5, the first Sunday after the Paschal full moon on April 1. The variability of Easter’s date stems from its connection to the lunar calendar and the spring equinox. The earliest possible date for Easter is March 22, though this is rare. The last occurrence was in 1818, and the next will be in 2285. Conversely, the latest Easter can fall is April 25, which last happened in 1943 and will occur again in 2038. This shifting schedule reflects the interplay between the Gregorian calendar and the lunar cycle, a system rooted in early Christian traditions. Easter holds profound religious significance for Christians, marking the resurrection of Jesus Christ. According to Christian teachings, Jesus rose from the dead three days after his crucifixion and burial on Good Friday, symbolizing the triumph over death and the fulfillment of God’s plan for salvation. This event is central to Christian faith, representing divine love and redemption. Celebrations vary across denominations but often include church services. Protestant traditions in North America feature sunrise services, inspired by the Gospel accounts of Mary Magdalene discovering an empty tomb at dawn. Lutheran, Anglican, and Roman Catholic communities hold Easter Vigil services on Saturday evening, followed by Sunday services.#easter #spring_equinox #paschal_full_moon #easter_bunny #easter_egg
