Original Summary

Getty Images Astronomical autumn begins this week, with the autumn equinox taking place in the early hours of Wednesday. The equinox will occur at 01:06 BST on 23 September, according to Royal Museums Greenwich. It is a precise moment in time when the Sun crosses the celestial equator and neither hemisphere is tilted towards or away from the Sun, meaning day and night are roughly equal in length across the world. And while the equinox itself cannot be seen, the day has cultural and spiritual significance for some people. Gatherings take place at sites including Stonehenge, where people come together to mark the occasion and watch the Sun rise. Getty Images / Many people, including druids and pagans, gather at Stonehenge to take part in a autumn equinox celebration What is the difference between the equinox and equilux? The word "equinox" comes from Latin and means equal night. At the equinox, the daylight measurement is taken from the point when the centre of the Sun is at the horizon, and is 12 hours sunrise to sunset and 12 hours sunset to sunrise. However, it is the top edge of the Sun which is visible first at sunrise and last at sunset. Because of light refraction - light being bent by the atmosphere - there is still light for a time when the Sun is not directly visible. This adds extra time to daylight hours. In autumn, this means that the time when day and night are actually equal happens after the equinox. This is known as the "equilux", which means equal light. This year, that happens in the UK on Friday 25 or Saturday 26 September, depending on your latitude. Where in the UK are days getting shorter fastest? Although the equinox happens at the same moment everywhere, the change in hours of daylight is not the same across the UK. The further north you go, the bigger the difference between the long days of summer and the short days of winter. That means places in northern Scotland are losing daylight more quickly at this time of year than parts of southern England. Around the autumn equinox, the change is particularly noticeable as sunrise gets later and sunset earlier. BBC Weather Watchers/big blue bear / Sunrises like this one in Dunbar, East Lothian, will will get progressively later as autumn continues Does the equinox mean colder weather is on the way? The autumn equinox may mark the start of astronomical autumn, but it does not necessarily mean there will be a sudden change in the weather. As the Sun gets lower in the sky and the days shorten, temperatures generally fall as we head further into autumn. So far this September, UK mean temperatures have been above average overall, according to the Met Office. There is still some warmth in the forecast this week, particularly in the south-east of England, before rain moves across the UK on Wednesday, followed by fresher conditions on Thursday. Towards the end of September, changeable weather is expected, with temperatures likely to remain slightly above average overall. However, clearer and cooler nights could bring some fog and even frost in places.

中文概览

中文标题： 2026年秋分：何时到来及会发生什么

天文秋季本周开始，秋分将于英国夏令时9月23日01:06到来，届时太阳经过天球赤道，全球昼夜大致等长。受大气折射影响，昼夜真正等长的“equilux”出现在9月25或26日。秋分有文化与宗教意义，有人聚集巨石阵观看日出；越往北白昼缩短越快，秋分并不意味天气骤冷。

  • 情报分类：综合情报
  • 分类依据：秋分天文与天气科普，属综合资讯。
  • 信息来源：英语新闻 / BBC News Top Stories
  • 发布时间：2026/9/22 08:05:52