The equinox

[Michael Rolls]

I am puzzled. Normally the equinox surely occurs on the 21st or 22nd of March, but according to Google, this year (for my longitude) it will occur at 9:45 PM on Monday. That's not the real puzzle, though according to the 'local times' site it occurred in the early hours of this morning, because (I check the site daily', it tells my I have 12 hours and 1 minute of daylight – as does Hereford and London.

https://www.timeanddate.com/worldclock/@2655394

[klondike]

Google doesn't actually have much content of its own. I just links to websites and sometimes includes extracts from a site in the search results. Perhaps the site was wrong. The mass of migrants crossing the channel may have had an impact on the rotation speed of planet earth but it won't have had enough impact on our calendars to be measured nor on the earth's orbital parameters.

From what I can see all of the sites seem to be agreeing on 20th. I suspect the problem is down to our orbit not being an exact number of days but our calendar is with a (mostly) 4 yearly correction we call a leap year so fixed astronomical events will move by our calendar.