Summary for : (675) Ludmilla

DynT.TT.BT T.L B T.DDensity (g/cm^3)Δρ/ρDiameter (km)ΔD/DMass (kg)ΔM/MRefAvg.M
MBASS- | -Sw12.12 ± 22.43   (X)185 %67.7 ± 0.91.4 %1.97e+18 ± 3.64e+18185 %SEVM
MBASS- | -Sw5.18 ± 48.67   (E)940 %67.7 ± 0.91.4 %8.40e+17 ± 7.89e+18940 %Sw.avg
MBAS73.99 ± 15.05   (X)20 %67.7 ± 0.91.4 %1.20e+19 ± 2.40e+1820 %C?

Average asteroid densities (g/cm^3):
C = 1.3 ± 0.6, B = 2.4 ± 0.5, S = 2.7 ± 0.5, M = 3.5 ± 1.0, P = 2.8 ± 1.6, X = 1.9 ± 0.8, Xc = 4.9 ± 0.9, Xk = 4.2 ± 0.7 (Ref)

Object is a Gaia target for mass determination !

Additional resources:
3D Model | JPL New Horizons | Minor Planet Center | Wikipedia (these auto-generated links might not work)

Note: The density estimates have been ranked from (A) to (E), corresponding to the relative error: (B) less than 20%, (C) between 20 and 50%, (D) between 50 and 100%, and (E) more than 100%. (A) stands for (presumably) reliable estimates (accuracy better than 20%), based on more than 5 mass estimates and 5 diameter estimates, or a spacecraft encounter. Apparently unrealistic densities (ρ > 8) are tagged with (X).

EVM: average by using the Expected Value Method (Ref). w.avg: weighted average (with w = 1/err^2).

T.T: Tholen Tax Class. T.B: Bus & Binzel Tax Class. T T.L: S3OS2 Lazarro (Tholen) Tax Class. T.L B: S3OS2 Lazarro (Bus & Binzel) Tax Class. T.D: DeMeo Tax Class.

Ref: S = SiMDA, C = Carry (2012)

Diameter estimates

DesignationDiameter / Err (km)ΔD/DMethodYearRefNχ2Use
(675) Ludmilla67.66 ± 0.941.4 % STM2011D83 0.00 1

Notes (N):
1: This estimate is discarded for the average diameter (and derived density) calculation in Carry (2012).
2: This estimate is discarded for the average diameter (and derived density) calculation in SiMDA (catalog).

STM : Standard Thermal Model.


EVM diam. average D = (67.7 ± 0.94) km   (ΔD/D = 1%, SNR = 71.98) Derived bulk density ρ = (12.12 ± 22.43) g/cm3   (Δρ/ρ = 185%, SNR = 0.5)


References
D83(2011):Usui, F., Kuroda, D., Müller, T.G., Hasegawa, S., Ishiguro, M., Ootsubo, T., Ishihara, D., Kataza, H., Takita, S., Oyabu, S., Ueno, M., Matsuhara, H., Onaka, T., 2011. Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey. Publications of the Astronomical Society of Japan 63, 1117–1138.

Mass estimates

DesignationMass / Err (kg)ΔM/MMethodYearRefNχ2Use
(675) Ludmilla1.20e+19 ± 2.39e+1820 %Ephem 2010M93217.63 1
(675) Ludmilla6.47e+17 ± 3.14e+1749 %Ephem 2019M12617.63 2

plot, average mass and derived density

All

Notes (N):
1: This estimate is discarded for the average mass (and derived density) calculation in Carry (2012).
2: This estimate is discarded for the average mass (and derived density) calculation in SiMDA (catalog).
3: This estimate is an average of individual solutions listed before under the same reference (e.g. M125).

Ephem : Planetary ephemeris solution.


EVM mass average M = (1.966 ± 3.637) × 1018 kg   (ΔM/M = 185%, SNR = 0.5) Derived bulk density ρ = (12.12 ± 22.43) g/cm3   (Δρ/ρ = 185%, SNR = 0.5)


References
M93(2010):Fienga, A., Manche, H., Kuchynka, P., Laskar, J., Gastineau, M., 2010. INPOP10a. Scientific Notes.
M126(2019):Fienga, A., et. al, 2019. INPOP19a planetary ephemeris. Notes Scientifiques et Techniques de l'Institut de mécanique céleste,