Summary for : (747) Winchester

DynT.TT.BT T.L B T.DDensity (g/cm^3)Δρ/ρDiameter (km)ΔD/DMass (kg)ΔM/MRefAvg.M
MBAPCCB | B-0.10 ± 0.53   (X)535 %170.6 ± 4.92.9 %2.60e+17 ± 1.39e+18535 %SEVM
MBAPCCB | B-0.00 ± 1.75   (X)51578 %169.8 ± 5.93.5 %8.71e+15 ± 4.49e+1851578 %Sw.avg
MBAB1.47 ± 0.87   (D)59 %170.1 ± 6.73.9 %3.81e+18 ± 2.22e+1858 %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)

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
(747) Winchester171.71 ± 3.091.8 % STM2004D93 0.13 1
(747) Winchester159.14 ± 5.163.2 % STM2010D64 4.94 2
(747) Winchester185.98 ± 10.415.6 % NEATM2010D64 2.18 3
(747) Winchester171.00 ± 15.008.8 % MDM:LO2011D78 0.00 4
(747) Winchester170.08 ± 2.511.5 % STM2011D83 0.04 5

plot, average diameter and derived density

All

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).

MDM:LO : Multi-Data Modeling: Lightcurves + Occultations. NEATM : Near-Earth Asteroid Thermal Model. STM : Standard Thermal Model.


EVM diam. average D = (170.6 ± 4.90) km   (ΔD/D = 3%, SNR = 34.80) Derived bulk density ρ = (0.10 ± 0.53) g/cm3   (Δρ/ρ = 535%, SNR = 0.2)


References
D64(2010):Ryan, E.L., Woodward, C.E., 2010. Rectified Asteroid Albedos and Diameters from IRAS and MSX Photometry Catalogs. Astronomical Journal 140, 933–943.
D78(2011):Ďurech, J., Kaasalainen, M., Herald, D., Dunham, D., Timerson, B., Hanuš, J., Frappa, E., Talbot, J., Hayamizu, T., Warner, B.D., Pilcher, F., Galád, A., 2011. Combining asteroid models derived by lightcurve inversion with asteroidal occultation silhouettes. Icarus 214, 652–670.
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.
D93(2004):Tedesco, E.F., Noah, P.V., Noah, M.C., Price, S.D., 2004. IRAS Minor Planet Survey. NASA Planetary Data System. IRAS-A-FPA-3-RDR-IMPS-V6.0.

Mass estimates

DesignationMass / Err (kg)ΔM/MMethodYearRefNχ2Use
(747) Winchester7.96e+15 ± 3.98e+1550 %Ephem 2009M80124007.94 1
(747) Winchester2.94e+18 ± 2.94e+1710 %Ephem 2009M8683.10 2
(747) Winchester1.20e+19 ± 4.59e+1838 %Ephem 2010M9326.54 3
(747) Winchester8.10e+18 ± 5.86e+1872 %Deflec 2011M971.79 4
(747) Winchester4.31e+18 ± 4.65e+18108 %Deflec 2011M970.76 5
(747) Winchester5.25e+18 ± 4.47e+1885 %Deflec 2011M971.25 6
(747) Winchester1.33e+19 ± 1.47e+1811 %Ephem 2011M1001278.69 7
(747) Winchester5.38e+18 ± 9.33e+1717 %Ephem 2019M12630.15 8

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).

Deflec : Orbital deflection (close encounter) of one or several test asteroids (classical LSQ). Ephem : Planetary ephemeris solution.


EVM mass average M = (2.599 ± 13.895) × 1017 kg   (ΔM/M = 535%, SNR = 0.2) Derived bulk density ρ = (0.10 ± 0.53) g/cm3   (Δρ/ρ = 535%, SNR = 0.2)


References
M80(2009):Fienga, A., Laskar, J., Morley, T., Manche, H., Kuchynka, P., Le Poncin-Lafitte, C., Budnik, F., Gastineau, M., Somenzi, L., 2009. INPOP08, a 4-D planetary ephemeris: from asteroid and time-scale computations to ESA Mars Express and Venus Express contributions. Astronomy and Astrophysics 507, 1675–1686.
M86(2009):Folkner, W.M., Williams, J.G., Boggs, D.H., 2009. The planetary and lunar ephemeris de 421. IPN Progress Report 42, 1–34.
M93(2010):Fienga, A., Manche, H., Kuchynka, P., Laskar, J., Gastineau, M., 2010. INPOP10a. Scientific Notes.
M97(2011):Zielenbach, W., 2011. Mass Determination Studies of 104 Large Asteroids. Astronomical Journal 142, 120–128.
M100(2011):Fienga, A., Kuchynka, P., Laskar, J., Manche, H., Gastineau, M., 2011. Asteroid mass determinations with INPOP planetary ephemerides. EPSC-DPS Joint Meeting 2011 , 1879.
M126(2019):Fienga, A., et. al, 2019. INPOP19a planetary ephemeris. Notes Scientifiques et Techniques de l'Institut de mécanique céleste,