Proposals for the masses of the three largest asteroids,the Moon-Earth mass ratio and the Astronomical Unit

We propose to the NSFA (the IAU Working Group on Numerical Standards for Fundamental Astronomy) the following representative values and realistic uncertainties for the masses of the three largest asteroids (Ceres, Pallas, Vesta), to be used as the current best estimates: Unlike the values previously adopted in the Astronomical Almanac, these are consistent with nearly all of the twenty or so modern accurate determinations from various authors. We also have proposed the following values for the Moon-Earth mass ratio and the astronomical unit in meters obtained from the ephemeris improvement processes at JPL in Pasadena and at IAA RAS in St.Petersburg: M _Moon/M _Earth =  0.0123000371(4) and AU =  149597870700(3) m. The numerical value of the AU in meters is identical in both the TDB-based and the TCB-based systems of units if one uses the conversion proposed by Irwin and Fukushima, Brumberg and Groten, Brumberg and Simon.