It’s time to pack away your jumpers and gloves – spring has officially sprung!
At precisely 14:46 GMT today we have the Vernal Equinox, marking the exact moment when the centre of the sun crosses the plane of Earth’s equator.
From today, observers anywhere on Earth will see the sun’s path in the sky continue its movement further north every day.
That will last until the summer solstice (21 June), after which the sun begins travelling south.
The arrival of the Vernal Equinox means we can finally wave goodbye to winter, and say hello to spring.
‘Equinoxes are associated with the changing seasons,’ NASA explained.
‘In March, Northern Hemisphere observers welcome the longer, warmer days heralded by their vernal, or spring, equinox.
‘But Southern Hemisphere observers note the shorter days – and longer, cooler nights – signaled by their autumnal, or fall, equinox. Come September, the reverse is true.’
At precisely 14:46 GMT today we have the Vernal Equinox, marking the exact moment when the centre of the sun crosses the plane of Earth’s equator
The equinox – from Latin, meaning equal (equi) night (nox) – occurs twice every year.
In 2026, the equinoxes will occur on 20 March at exactly 14:46 UTC, and again on 23 September, at 00:05 UTC.
During the event, the sun shines equally on both the Northern and Southern Hemisphere.
For this reason, it’s the only times of the year when the North and South Poles are simultaneously lit by sunlight!
While you might assume that the length of day and night on the equinox is equal, this isn’t actually the case.
‘The date for that split depends on your latitude, and may occur a few days earlier or later than the equinox itself,’ NASA explained.
‘The complicating factors? Our Sun and atmosphere!’
Our sun is a sphere and not a point light source, which means its edge is refracted by our atmosphere as it rises and sets.
‘Equinoxes are associated with the changing seasons,’ NASA explained. ‘In March, Northern Hemisphere observers welcome the longer, warmer days heralded by their vernal, or spring, equinox’
This adds several minutes of light to every day.
‘The Sun doesn’t neatly wink on and off at sunrise and sunset like a light bulb, and so there isn’t a perfect split of day and night on the equinox – but it’s very close,’ NASA added.
Some of you might be reading this story slightly confused, having thought that spring has already sprung.
Well, it already has – that is, if you go by the meteorological definition.
Rather than using the equnioxes, this method divides the year into four fixed seasons, each lasting three months, making it easier to track weather patterns and compare statistics.
‘In the UK, meteorological spring always begins on 1 March and ends on 31 May,’ the Met Office explains.
