The barycenter of our solar system is not the sun, but a changeable location outside of the center point of the sun. A often used diagram of that relation is shown below, originated from the Wikipedia article.

Does exist one or more practical quite observations that confirm the accordance of the real changing of position of the barycenter of the solar system in relation to the center point of the sun with the theoretical results?

center point of sun and barycenter of sun system

  • $\begingroup$ It's an interesting question! I don't believe that the relative position between the Sun's center of mass and the solar system's barycenter can be measured in any other way than taking all of the observational data of the motion of all of the solar system objects that we know about and calculating their center of mass. In other words, there isn't anything else to compare with. But maybe I'm not understanding your question correctly. $\endgroup$
    – uhoh
    Jan 11, 2020 at 10:27
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    $\begingroup$ Indeed an interesting question. If there are mesurements It means that we can reverse the question and find for missing planets on our calculation. $\endgroup$
    – Swike
    Jan 11, 2020 at 14:20
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    $\begingroup$ As @uhoh notes, the barycenter is a theoretical point, not necessarily an observable one. It's the center of the reference frame NASA uses to calculate planet positions, so, if we're too far off on where the barycenter is, our planetary calculations would be inaccurate. $\endgroup$
    – user21
    Jan 11, 2020 at 17:45

1 Answer 1


Yes, measurements do exist. JPL takes very precise observations of many objects in the solar system and tries to obtain a location for the solar system barycenter.

The solar system barycenter is a hot topic especially in terms of PTA's, or pulsar timing arrays - we need precise a precise location for the solar system barycenter to do work with these pulsar timing arrays. I'll put some links at the bottom as well to help.

JPL does get its own calculations of the solar system barycenter, and AFAIK, they do this with use of what they call the Solar System Ephemeris - see more here and here, at their Solar System Dynamics page. They get precise locations of many objects in the solar system and then try to calculate a center of mass from there.

A cool walk-through of the effect of the eight planets and Pluto (and some other stuff) on the movement of the Sun.

  • $\begingroup$ +1 To get a feel for the level of matching between measured data and the model based on those measurements, looking at plots of residuals for various bodies in (for example) DE430 or 431 in ipnpr.jpl.nasa.gov/progress_report/42-196/196C.pdf show values that range from single digit kilometers down to centimeters for the Moon. $\endgroup$
    – uhoh
    Jan 12, 2020 at 0:24
  • $\begingroup$ Thank you, this answers the title question. Maybe the results of the JPL calculations are not static, but are compared with the reality and are improved with more accurate measurement results over the time. It would be interesting to know whether the graphic on top is correct, but this would be an other question. $\endgroup$
    – gotwo
    Jan 24, 2020 at 10:05

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