TheSkySearchers

Well, in this article, they did at least commit to answer the "within or outside the volume of the Sun" question. But not with any degree of accuracy: "...rather it is closer to the surface of the star."
(Which, if one scans the semantics, doesn't actually answer the inside vs outside question after all...)

seigell wrote: ↑Wed Jul 01, 2020 8:40 pm Well, in this article, they did at least commit to answer the "within or outside the volume of the Sun" question. But not with any degree of accuracy: "...rather it is closer to the surface of the star."
(Which, if one scans the semantics, doesn't actually answer the inside vs outside question after all...)

The purpose of the research is not to answer that question, though. In fact depending on the position of the planets it could be inside or outside the Sun's surface. In that context "closer to the surface" simply means that when it is inside it's closer to the surface and when it is outside it is closer to the surface.

The location of the solar system barycenter is dynamic and depends of how the planets are distributed at any given time. So it depends.

The original paper is here: https://arxiv.org/pdf/2001.00595.pdf

A Wikipedia link: https://en.wikipedia.org/wiki/Barycente ... e_the_Sun?

Interesting read - at least the methodology (statistics employed were over my head).

It still didn't express an opinion on the Intra/extra-Solarity of the SSB (not that I could see).

However, it is rather difficult to see how the non-Jovian Planets could exert much of an impact on the SSB. Saturn contributes only 1/11th the Gravitation of Jupiter, the Ice Planets even less.

seigell wrote: ↑Wed Jul 01, 2020 9:51 pm Interesting read - at least the methodology (statistics employed were over my head).

It still didn't express an opinion on the Intra/extra-Solarity of the SSB (not that I could see).

However, it is rather difficult to see how the non-Jovian Planets could exert much of an impact on the SSB. Saturn contributes only 1/11th the Gravitation of Jupiter, the Ice Planets even less.

As I said, depending on where the planets are, it’s possible for it to be inside or outside the solar surface.

It’s a conceptual error to consider mass alone. The product of the mass and the radius vector determines the position of the barycenter. If you multiply mass times the distance you’re going to see how it works.

like a spider sitting in stillness in the middle of her web

That conjures up quite a picture, a spider web the size of the solar system!

It will be interesting to see where NANOGrav goes with this as more data comes in.

Regards

Graeme

notFritzArgelander wrote: ↑Wed Jul 01, 2020 11:32 pm

seigell wrote: ↑Wed Jul 01, 2020 9:51 pm However, it is rather difficult to see how the non-Jovian Planets could exert much of an impact on the SSB. Saturn contributes only 1/11th the Gravitation of Jupiter, the Ice Planets even less.

It’s a conceptual error to consider mass alone. The product of the mass and the radius vector determines the position of the barycenter. If you multiply mass times the distance you’re going to see how it works.

Correct - only actually it is product of mass over radius vector squared. And that is how I derived the "1/11th of Jupiter's contribution" for Saturn (actually 1/11.018 - but who's counting?).
And the Ice Planets??
Uranus = 1/302.6th Jupiter
Neptune = 1/620.4th of Jupiter
Even if all the major Planets were lined-up behind Jupiter, they wouldn't contribute much to disturbing the SSB.
And we can discount the Kuiper and Oort objects, as their masses are distributed roughly equal around the Sun (netting zero).

seigell wrote: ↑Thu Jul 02, 2020 3:18 pm

notFritzArgelander wrote: ↑Wed Jul 01, 2020 11:32 pm

seigell wrote: ↑Wed Jul 01, 2020 9:51 pm However, it is rather difficult to see how the non-Jovian Planets could exert much of an impact on the SSB. Saturn contributes only 1/11th the Gravitation of Jupiter, the Ice Planets even less.

It’s a conceptual error to consider mass alone. The product of the mass and the radius vector determines the position of the barycenter. If you multiply mass times the distance you’re going to see how it works.

Correct - only actually it is product of mass over radius vector squared. And that is how I derived the "1/11th of Jupiter's contribution" for Saturn (actually 1/11.018 - but who's counting?).

No it is not the radius vector squared. It is the radius vector alone.

Squaring the radius vector gives the moment of inertia not the barycenter.

See this link for the correct definition https://en.wikipedia.org/wiki/Center_of ... oordinates

Which is different from the moment of inertia: https://en.wikipedia.org/wiki/Moment_of ... Point_mass
It's the moment of inertia that involves the square. The center of mass / barycenter involves only the first power.