What is the Solstice ?

There at least a dozen different important topics open for adjustment, modification and discussion in the NASA website aimed at children -

https://scijinks.gov/solstice/

The Northern European structures from antiquity still retain the Solstice alignments even though some of these structures are built centuries apart as in the case of Newgrange and Stonehenge. In other words the relationship between the North and South poles to the Sun and the circle of illumination remain the same today as they did many thousands of years ago thereby obliterating the notion of axial precession as a working principle and as a consequence of the precession of the Equinoxes.

I have no problem doing people's jobs for them in this corner of the internet but then again there is no appetite for anything other than flawed set pieces learned in the classrooms or schools and colleges and the lethargy which accompanies it.

The Solstice is explained using two intertwined rotations arising from intrinsic rotation with its traits and the second arises from the orbital motion with its separate traits.

The journey of the the North and South poles to their present position is fascinating and began 3 months ago on the Equinox. At the North pole the Sun appeared for the first time and circled the local horizon which amounts to a handful of miles as the surface point exited the circle of illumination -

https://www.youtube.com/watch?v=okw6Mu3mxdM

That circle where the Sun remains constantly in view will extend out to its maximum diameter next week with its circumference coincident with the Arctic circle and seen in the EPIC graphic beside the actual image of the Earth recently. The Solstice is therefore an astronomical event where the polar points are a maximum distance from the terminator -

https://epic.gsfc.nasa.gov/

The old solstice explanation trundled out this time every year would look facile to those who have some sense of this new approach to the seasons by focusing on the polar day/night cycle and its rotational cause . I would say to those who engage with the time lapse and imaging to just get on with the development and leave the 'tilting' Earth to those who can't be agile with their reasoning.