The Spring Equinox and big moons
Post categories: weather
| 08:39 UK time, Tuesday, 22 March 2011
I have been away on holiday so this is my first blog for a while. If you thought the moon looked bigger and brighter than usual over the weekend - you weren't imagining things - it was! In fact it was the and a few of you caught it on camera.
Moon by Mike Davies
Sunday night also marked the Spring Equinox which occurred at 11.21pm in the UK. The equinox refers to the moment that the sun crosses directly overhead at the Earth's equator and some people consider this to be the first day of Spring in the northern hemisphere.
The word equinox derives from the Latin words aequus (equal) and nox (night). It means equal day and night. But in reality, the day is slightly longer than the night at an equinox.
This is because the sun is not a single point of light, but appears to be a disc. So when the centre of the sun is still below the horizon, the upper limb is already visible and emits light.
The atmosphere also refracts light downwards, so even when the upper limb of the sun is still below the horizon, its rays already reach around the horizon to the ground. This combination makes the day slightly longer than the night.
In Wales, day and night were almost equal on 17 March before the Spring Equinox.
At the North Pole, polar bears celebrated the first appearance of the sun in six months but at the South Pole the penguins are preparing for six months of darkness!
Weatherwise the next few days will be mostly dry with high pressure over us. Cloud amounts will vary from day to day but if you see some sunshine it will turn out warm with temperatures rising as high as 17 Celsius.
However, it looks like turning colder next weekend so we haven't seen the last of the frost just yet.
Comment number 1.
At 23rd Mar 2011, Steven wrote:I actually didn't notice a different in the size or brightness of the moon, but I have to admit I don't look at it all that much
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