Where can I find the best values to use for standard gravitational parameters of solar system bodies for numerical simulation experiments?

Here are two sets I've put together. The first set is from Wikipedia, the second set is from the a JPL progress report listing the masses used for the calculation of the DE421 ephemeris.

In addition to the Sun and planets, I've included Earth's Moon, and the three largest asteroids. I am not sure how I should handle the masses of the larger moons of the large planets; I assume they are not counted here and I should deal with them separately.

Is there a significantly better "master table" than the DE430/431 values, or is that about as good as it gets?

NOTE: units are MKS

            Wikipedia:        JPL: DE421          JPL: DE430/431
           (1) unless         (2) unless            (6) unless 
         otherwise noted     otherwise noted       otherwise noted
        -----------------  --------------------  --------------------
Sun     1.32712440018E+20  1.32712440040944E+20  1.32712440040944E+20
Mercury 2.2032E+13         2.203209E+13          2.203178E+13
Venus   3.24859E+14        3.24858592E+14        3.24858592E+14
Earth   3.986004418E+14    3.98600436233E+14     3.98600435436E+14
Moon    4.9048695E+12      4.902800076E+12       4.902800066E+12
Mars    4.282837E+13       4.2828375214E+13      4.2828375214E+13
Ceres   6.26325E+10        6.2178E+10            6.28093938E+10
Pallas  2.11E+20*G(4,5)    1.3402E+10            1.3923011E+10
Vesta   2.59076E+20*G(3,5) 1.7630E+10            1.7288009E+10
Jupiter 1.26686534E+17     1.267127648E+17       1.267127648E+17
Saturn  3.7931187E+16      3.79405852E+16        3.79405852E+16
Uranus  5.793939E+15       5.7945486E+15         5.7945486E+15
Neptune 6.836529E+15       6.836535E+15          6.83652719958E+15

G = 6.67408E-11 (5)
  • 1
    $\begingroup$ Looking at the sources on the Wikipedia page, I see that the Ceres figure is based on Dawn data from 2015, Mars from 2011, while some of the other sources date to 2005, so the data straddles that of DE 421. $\endgroup$ Sep 8 '17 at 14:03
  • 2
    $\begingroup$ naif.jpl.nasa.gov/pub/naif/JUNO/kernels/spk/de436s.bsp.lbl but, again, not really different. $\endgroup$
    – user7073
    Sep 8 '17 at 15:07
  • 5
    $\begingroup$ @uhoh, My apologies for not being clear in my comment, so let me offer two clarifications: 1) Gravitational Parameters and planetary ephemerides are inherently linked, so that they can change for any iteration of DE. I'm not sure if they are estimated every time, but they can be. 2) I didn't mean to imply that DE436 was the latest and greatest. JPL produces DE files specifically for missions at times, and the fact that the file path for the DE436 contains JUNO implies that it was produced for that mission, and not meant for general consumption. DE431 may be the official latest/greatest $\endgroup$ Sep 14 '17 at 20:39
  • 3
    $\begingroup$ I'll note that my understanding of the generation of the DE kernels is the same as that of @DuffBeerBaron. They are built for specific missions, but they encompass all of the objects known to be useful to that mission, and possibly more. However, these values can be refined over time: the more probe we send out, the more orbital determination solutions we can compute, and therefore the better the resolution of the GM values. I'll also note that DE438 has been released a few weeks ago, for JUNO as well. $\endgroup$
    – ChrisR
    Jul 21 '18 at 17:19
  • 4
    $\begingroup$ One reason for the discrepancy between the wikipedia vs DE values for Jupiter, Saturn, and Uranus is that the wikipedia values are for the planet only while the DE values are for the planetary system (the planet plus its moons). Even then, the wikipedia values appear to be off, and except for Uranus, those values are unreferenced (and the reference for Uranus is an old 1992 paper). OTOH, the wikipedia value for Neptune appears to be an unreferenced value for the Neptunian system as a whole. $\endgroup$ Oct 21 '18 at 11:28

If you consider the ephemeris files put out by JPL as the final say in terms of simulations, then the data they put in the PKC files alongside the SPK files are the authoritative value, because that's the data used in the simulations.

These values are available at https://naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/gm_de431.tpc

For completeness, JPL has a list of planetary satellite physical parameters at: https://ssd.jpl.nasa.gov/?sat_phys_par that is pretty comprehensive.

As a side note, I was looking for the GM value for Nerid, and it's listed on that page, but in the files found on the ftp site along with the SPK files, Nerid's value is set to 0. This suggests that there are discrepancies between the value used in the simulation and what you can find in this table.

  • $\begingroup$ Hi @uhoh, that depends on what/who you consider an authority. Or, in your case "The" authority. If you consider the ephemeris files put out by JPL as the final say in terms of simulations, then the data they put in the pkc files are the authoritative value, because that's the data used in the simulations (naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/gm_de431.tpc) $\endgroup$ Jul 22 '18 at 3:17
  • 1
    $\begingroup$ Thanks for all the helpful links! It's great when someone takes the time to revive an old question and then track down and post links to sources of helpful information. $\endgroup$
    – uhoh
    Jul 22 '18 at 15:53
  • 1
    $\begingroup$ @uhoh happy (and surprised) I could help, being a new comer and all :) $\endgroup$ Jul 23 '18 at 0:03
  • 5
    $\begingroup$ For reference, the numbering system in the first file linked by @KaushikGhose is as follows: Bodies 1 to 9 are Mercury, Venus, the Earth and the Moon, the Mars system, the Jovian system, the Saturnian system, the Uranian system, the Neptunian system, and the Plutonian system. BODY10 is the Sun. The file also lists values for the planets themselves and for key moons. Moons are prefixed by the 100 times the system number plus an index for the moon (e.g., the Moon is BODY301). The planets themselves are the 100 times system number plus 99 (e.g., the Earth is BODY399, and Pluto is BODY999). $\endgroup$ Oct 21 '18 at 11:50

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