Circumpolar constellations

Simon,
I’m wondering if you have any words on the perceived 360° rotation of Ursa Minor?


As I understand, this perspective change is the result of Man’s Yearly Path in absolute space. As wiki says, people in the northern hemisphere will notice this seasonal change. I’ve noticed this myself before reading the Tychos and am now wondering how you would explain this in contrast to the Copernicans? Would it also be the case that the constellation Lyra will appear to rotate 360° for northern hemisphere viewers when Vega is the north star in the future? Is earth’s tilt a factor here?
Thank you

Dear babayaga,

I wish to warmly thank you for inspiring me to take a closer look at the yearly motions of Polaris (which of course is the ‘tip’ of the Little Dipper).

Yes, the Big Dipper revolves around Polaris daily and yearly - and that is equally accounted for by the Copernican and the Tychos models. In both models. of course, the Earth revolves counterclockwise around its polar axis every day - and also ‘ticks’ annually by ‘one extra’ 360° as it ‘follows’ the Sun : this is why the Earth actually revolves 366 times in a 365-day calendar year.

Yet, the Copernican model can not account for the observed oscillations of Polaris in RA (Right Ascension). Let me now try and illustrate what this means.

Year by year, the RA of Polaris is steadily increasing. For instance, in 2022 it was at about 3h of RA - and in 2100 (when Polaris will be as close to our polar line as it will ever get) it will be at 6h of RA. In the Tychos, of course, this is due to the Earth’s motion along its PVP orbit. However, as can be verified in the famed Stellarium simulator, Polaris regularly ‘retrogrades’ by about -3 (and up to -4 min) of RA between October and April of the following year. Here’s my best attempt at illustrating this with a 2-D graphic (click on image to enlarge) :


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As you can see, the Tychos has a way of explaining why Polaris is regularly observed to ‘retrograde’ by about 3min of RA between October and April every year (even though Polaris keeps moving ‘prograde’ over time - as we move from “LEFT” to “RIGHT” as of my above diagram): it is due to what I call “a Man’s Yearly Path” which reverses its course during those months.

Could the Copernicans explain this away by ascribing this to their claimed parallax of Polaris (7.54 mas)? Hardly: 7.54 mas (milliarcseconds) are equal to 0.000002094° - whereas 3 min of RA are equal to 0.75°.

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Now would this daily rotation be something like .98°, since it takes 365 days to make a full circle around the more distant Polaris? Does this also go for constellations/stars of a similar distance? Thanks.