It's the Autumnal Equilux today

[RayProudfoot]

Three days after the equinox we have the equilux today. I'm curious if sunrise / sunset times around the world are exactly the same as mine here in Cheshire.

Are yours?

Equilux.jpg

[Nossie]

This is mine from 185 miles away, does a few hundred make such a difference?


Dawn: 06:32 Sun Rise: 07:09 Moon Rise: 06:09 MoonVisible 0%
Dusk: 19:46 Sun Set: 19:09 Moon Set: 19:25
Daylight: 13:14 Day Length: 12:00 Moon Phase: New moon

[RayProudfoot]

@Nossie, shouldn't make any difference in the UK or even Europe. Check where you're getting those times from.

[sutne]

These times differ a lot between north and south.
Strictly I have not Equilux this autumn:

Rise 07:24
Dawn 06:41
Day length 11:59
Set 19:24
Dusk 20:06
Daylight length 13:24

[RayProudfoot]

These times differ a lot between north and south.
Strictly I have not Equilux this autumn:

Rise 07:24
Dawn 06:41
Day length 11:59
Set 19:24
Dusk 20:06
Daylight length 13:24

I’m confused why the sun should rise earlier in Norway than the UK if local times relative to your longitude are being used. Surely the whole point of the Equilux is that sunrise and sunset times are the same irrespective of where you are on the planet.

The Equilux is global. No one misses out.

[Mapantz]

I’m confused why the sun should rise earlier in Norway than the UK

You're kidding, right?

The sun doesn't rise at the same time for everyone lol

[RayProudfoot]

You're kidding, right?

The sun doesn't rise at the same time for everyone lol

It should rise at the same local time around the equinox / Equilux.

[Nossie]

I was questioning myself there! It's quite common for the north of Scotland to have darker nights than say cornwall so a few minutes difference from here to there is quite normal.

equinox or not, physics still functions.

[Mapantz]

It should rise at the same local time around the equinox / Equilux.

That's impossible..

Just as an example, sunset is 19:00 here, in Dover, it sets at 18:47.

[RayProudfoot]

That's impossible..

Just as an example, sunset is 19:00 here, in Dover, it sets at 18:47.

Okay, so lux = light. Same amount of light wherever you are. If there’s 12 hours between sunrise and sunset that’s correct. It’s just a coincidence my times are exactly 07:00 and 19:00.

[mcrossley]

The actual times will vary with your longitude within the timezone as well as how well the time zone is centred on the corresponding longitude.

[RayProudfoot]

The actual times will vary with your longitude within the timezone as well as how well the time zone is centred on the corresponding longitude.

Indeed Mark. One degree longitude = 4 mins and the whole of the British Isles is in one time zone. Lowestoft is close to 2°E and the west of NI 10°W. That’s 12° or 48 minutes - close to one time zone. What we all share is 12 hours of daylight for this day.

[sutne]

Here is some explanation:

https://www.timeanddate.com/news/astronomy/equilux-2022

And you can see from this that the lines are not straight:
https://www.timeanddate.com/worldclock/ ... 20925T2006

[mcrossley]

Yes, if you look at just the daylight length then they should all be about 12:00. The up to 24h difference in the day starting/ending depending where you are on the globe should make little difference. But the solar calculations used by most programs (including CMX) are simplifications and can be +/- 1 minute at mid latitudes increasing with latitude until they go what may be considered inaccurate above around 70 - iirc.

[AllyCat]

Hi,

Sunset and Sunrise are normally defined when the (top) Edge of the sun crosses the horizon, which is about half a degree from its centre. Also there is refraction in the atmosphere so that "Sunset" and "Sunrise" actually occur with the centre of the sun about 0.8 degree below the (mathematical) horizon. That's why this "Equilux" is a few days later than the "Equinox". But it rather depends how you define "Lux" and "Not Lux".

And of course "National Time" (e.g. BST) is certainly not the same as "Local Time" (dependent on the site Longitude), nor "Solar Time" (dependent also on the "Equation of Time").

Cheers, Alan.