Autumnal Equinox 2022
It’s almost that time of year again. The Autumnal Equinox (in the Northern hemisphere) takes place in the early hours of tomorrow morning (Friday 23nd September 2022) at 02.04 Irish Summer Time (01.04 UT). That is way past my bedtime so I thought I’d post this a few hours early.
Although the term `equinox’ refers to a situation in which day and night are of equal length, which implies that it’s a day rather than a specific time, the astronomical equinox is more accurately defined by a specific event, i.e. when the plane defined by Earth’s equator passes through the centre of the Sun’s disk (or, if you prefer, when the centre of the Sun passes through the plane defined by Earth’s equator). Day and night are not necessarily exactly equal on the equinox, but they’re the closest they get. From now on days in the Northern hemisphere will be shorter than nights and they’ll get shorter still until the Winter Solstice on 21st December at 21.48 Irish Time.
Many people take the autumnal equinox to be the end of summer. There is a saying around these parts, however, that `Summer is Summer to Michaelmas Day’ (September 29th), which is not until next week. I must say, though, though it doesn’t feel particularly summery today.
Anyway, this is Welcome Week in Maynooth and we’re due to start teaching first year students next week, on Monday 26th September. It seems to be a bumper year for our intake, with 113 so far registered. That’s more than we’ve had in the 1st year since I arrived here. Returning students commenced on Monday 19th. I already gave my first lecture on Vector Calculus and Fourier Series to this class yesterday; I have another with them tomorrow. We have about the same number of students in Year 2 this year as we had last year.
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In the Dark 
September 22, 2022 at 10:08 pm
That’s when the next episode of Rings of Power is released…
September 23, 2022 at 12:25 am
Although the equinox is thought by some to be the end of summer, in the Welsh language the end of summer is marked by the end of July or ‘gorffennaf’. The verb-noun Gorffen translates as finishing, and Haf is the Welsh for summer. So ‘gorffennaf’ is ‘summer finishing’.
In this system, summer is defined as 1st May to 31st July, autumn as 1st August to 31st October, winter 1st November to 31st January and spring as 1st February to 30th April. The equinoxes (equinoctes?) and solstices all fall in the middle month of each (Welsh) season.
September 23, 2022 at 9:24 am
This is the old Celtic calendar which survives also in Ireland. We have Bank Holidays to mark the cross-quarter days, half way between the equinoxes and the solstices:
https://telescoper.wordpress.com/2020/08/03/la-saoire-i-mi-lunasa/
September 23, 2022 at 6:12 pm
When summer ends depends on your definition of summer, obviously. And there is a hysteresis lag between insolation and warmth. I used to regard it as the end of the cricket season, but they have pushed that so late – unwisely as the county championship has often just sputtered out into rain – that I now take the end of August as my rule of thumb.
Whatever changes are made to the county championship, I’d love to see a climax no later than mid-September, after the last Test, and iwth the England-contracted players turning out for their counties. Strauss et al can hardly complain about the lack of 4-day viewers when the best players aren’t on view.
September 23, 2022 at 7:59 pm
There’s still another round of matches to go in the County Championship which seems very late. Still, David Lloyd won’t complain. He scored 313* for Glamorgan against Derbyshire this week.
September 23, 2022 at 8:36 pm
Six years ago there was a thrilling end to the championship on September 23rd in which if either of Middlesex or Yorkshire won the match between them then they’d win the championship, but otherwise Somerset would. Of course that match was always going to produce a result, no matter how contrived, and Middlsex took the honours. But in some subsequent series the championship has dwindled in late September due to rain.
I have seen a batsman complete a first-class triple century – Michael Hussey at Bristol for Northants in 2002.
September 23, 2022 at 8:39 pm
David Lloyd’s triple century broke several records including the highest score by someone called David Lloyd.