Well, if you're lucky you learn something new each day.
Currently in Gracemere (Rockhampton) and went to check out the local wall to mark the 'Tropic of Capricorn' as it's on a different corner (Further south) than shown on the town map.
Checked the latitude with my GPS Navigator and found that it wasn't at S 23d 30' as I was taught at school many, many decades ago.
Back to the van and Googled Tropic of Capricorn'.
We it was a revelation to learn that it changes each year and is currently at S 23d 26'16".
And is moving north at around 15 metres each year.
That means the wall in town and all those other monuments and signs on the highwyas throughout the country are incorrectly placed.
I'll be damned.
ozjohn

Well, thats a strange one, maybe with the earths crust moving all the time, hence the earthquakes, the Tropic of Capricorn has to change too.

I guess where we stood on it at Longreach would be wrong as well? Oh well, win some, loose some, and most wouldn't know the difference - particularly when we send the photos overseas.

Today is the equinox - that is, theoretically, equal hours of daylight and dark on the tropic. This also varies from year to year because of that variation. My birthday is the shortest day of the year, 21/06, and it's due to the lack of sunshine that I'm so short. Ha, ha, ha, ha.

all of the marking of the tropic of capricorn in rton were never geographically correct. the true line when i was a boy some 50 years ago was near the neerkol orphanage on the western highway. our major at the time rex pilman deceided that it would attract more tourist and so money to the town if it it was placed on the southern or bruce highway. so it sat on the bruce highway untill the main roads revamped the road and by passed the sign. so again the tropic of capricorn was moved to it present location at the tourist info centre. now you can say the line moves geographically some many metres a year. but for political and monitery reason it has been moved a lot more . brian & kerry 2010 a van mobile home

So does anyone know if there is such debate on the western side of the country?

Tourist "authorities" (for want of a better word) always work on the principle of never letting the truth get in the way of a good (sometimes outrageous) claim. In a bygone era there were some surveying errors when it came to marking these geographical features. At Cameron Corner the marker installed as part of a survey for the 1988 Bicentenary (I think) is a short distance from the previously surveyed NSW, Qld, SA border. The most notable example of this is the Vic-SA border that is a few kilometres from where it should be. As technology has advanced map datums have been updated and this may be a factor too. If you look up the precise latitude of the tropic, a simple exercise with a GPS would determine the validity of any claim. Equinoxes and Solstices have precise astronomic definitions and the date varies (+ or - a day) due to time zones and whether or not it is a leap year.