How much does this Great Conjunction shift the solar system barycentre? (i guess it must?)

[markse68]

From my understanding the Sun orbits a point outside of its sphere as a result of the combined shifting gravitational pull of the planets and that Jupiter being the most massive has the largest effect. But Saturn is next most massive so I guess a conjunction like this must shift the barycentre further from the sun? But by how far? (compared to say when they’re on opposite sides to one another?)

Mark

[RT65CB-SWL]

I guess it does, but by how much is any ones guess... maybe a few millimetres.

As we know, the Moon is moving further away from Earth at about 3.8cms per year... kind of puts it into perspective.

[robin_astro]

Was going to do a back of envelope calculation but decided the answer must be out there already 

https://www.youtube.com/watch?v=oauf6W3Uz04

The barycentre is currently outside the sun

Cheers

Robin

Edited December 21, 2020 by robin_astro

[markse68]

38 minutes ago, Philip R said:

maybe a few millimetres.

 

32 minutes ago, robin_astro said:

Was going to do a back of envelope calculation but decided the answer must be out there already 

thanks Philip and Robin!

From the look of that graphic Robin linked to it looks like quite a large change. Saturn is about 1/3 the mass of Jupiter and about twice the distance from the Sun so as gravity diminishes by the square of the distance I think it must have 1/12th the gravitational pull on the Sun as Jupiter? Still quite a lot. 

Mark