Our barycentre

Our planets might affect also the Sun. They do this by shifting the centre of mass for the entire Solar System, which shift then churns up the Sun's interior. So claimed PD Jose in 1965 for the planets then known - excluding the ninth planet of the day, the Pluto-Charon duet, at the time unconstrained and in anycase resonant with Neptune.

Now cometh Ian R. Edmonds of Brisbane. (Good eye, Turtle!) Edmonds implicates the Brown-Batygin Planet Nine, specifically in the solar cycles Hallstaatt (2400 years) and Gleissberg (88 years). There's also Jose's own 177 year periodicity; this, Edmonds erases by Phase Modulation, to which concept I confess ignorance.

Edmonds is able to improve predictability of the solar cycles, which is awesome for satellites and future spacecraft.

Also, heliographic longitude has increased from 50° in 1965 to 53° in 2022. It might constrain where we look. Although I am unsold that the orbit be circular.

To be reminded, Planet Nine may or may not have seen in the early 1980s, for its part at a high ecliptic latitude - although I haven't seen followups yet. If not Planet Nine herself (the likeliest name will be Proserpine, which is even likelier now) this body may at least be some resonant like Pluto for Neptune.