The key points are temporarily unavailable. You can still read the full Story below.
Main Points
In many households the autumn season is traditionally marked as beginning on September 21, a date that has long been taught in schools and celebrated in calendars. However, astronomers and climatologists point out that this is a common misconception.
According to Martijn Peters, a science expert for HLN, the astronomical autumn does not start on September 21 this year. Instead, the autumnal equinox – the moment when day and night are of equal length – falls on September 23, 2024. This marks the official beginning of the astronomical season of autumn.
Peters explains that there are two widely accepted ways to divide the seasons. The first, the astronomical method, relies on the positions of the Earth relative to the Sun and the equinoxes and solstices. The second, the meteorological method, uses the calendar months, with autumn defined as September, October, and November. Because of this difference, the start date of autumn can vary depending on which system is referenced.
HLN’s science team highlighted that the confusion often arises from the overlap between the two systems. While the meteorological autumn begins on September 1, the astronomical autumn begins on the day of the equinox, which in 2024 occurs on September 23.
“It is a misunderstanding that still circulates widely,” said Peters. “The astronomical autumn starts on the equinox, which this year is on September 23, not on September 21.”
For those planning seasonal events or simply curious about the calendar, it is useful to remember that the astronomical definition of autumn is tied to the equinox, whereas the meteorological definition follows the calendar months.
Article source: www.hln.be | Image credit: www.hln.be
