Summary for : (89) Julia

DynT.TT.BT T.L B T.DDensity (g/cm^3)Δρ/ρDiameter (km)ΔD/DMass (kg)ΔM/MRefAvg.M
MBASKS | Ld-9.77 ± 4.44   (X)45 %110.8 ± 11.710.6 %6.96e+18 ± 2.26e+1833 %SEVM
MBASKS | Ld-10.36 ± 7.72   (X)75 %109.4 ± 12.511.4 %7.09e+18 ± 4.69e+1866 %Sw.avg
MBAX3.98 ± 1.27   (C)32 %147.6 ± 8.35.6 %6.71e+18 ± 1.82e+1827 %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
(89) Julia151.46 ± 3.092.0 % STM2004D93 172.80 1
(89) Julia128.53 ± 3.032.4 % STM2004D9412 34.08 2
(89) Julia134.27 ± 4.003.0 % STM2010D642 34.31 3
(89) Julia99.88 ± 0.020.0 % STM2010D642 300357.56 4
(89) Julia160.84 ± 6.534.1 % NEATM2010D64 58.63 5
(89) Julia118.82 ± 0.020.0 % NEATM2010D642 159162.01 6
(89) Julia140.00 ± 10.007.1 % MDM:LO2011D78 8.50 7
(89) Julia146.77 ± 1.901.3 % STM2011D83 357.59 8
(89) Julia148.08 ± 10.076.8 % NEATM2011D72 13.68 9
(89) Julia142.00 ± 4.002.8 % ADAM2017D100 60.68 10

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).

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


EVM diam. average D = (110.8 ± 11.73) km   (ΔD/D = 11%, SNR = 9.45) Derived bulk density ρ = (9.77 ± 4.44) g/cm3   (Δρ/ρ = 45%, SNR = 2.2)


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.
D72(2011):Masiero, J.R., Mainzer, A.K., Grav, T., Bauer, J.M., Cutri, R.M., Dailey, J., Eisenhardt, P.R.M., McMillan, R.S., Spahr, T.B., Skrutskie, M.F., Tholen, D., Walker, R.G., Wright, E.L., DeBaun, E., Elsbury, D., Gautier, IV, T., Gomillion, S., Wilkins, A., 2011. Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters. Astrophysical Journal 741, 68.
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.
D94(2004):Tedesco, E.F., Egan, M.P., Price, S.D., 2004. MSX Infrared Minor Planet Survey. NASA Planetary Data System. MSX-A-SPIRIT3-5-SBN0003-MIMPS-V1.0.
D100(2017):Hanuš, J., Viikinkoski, M., Marchis, F., et al., 2017. Volumes and bulk densities of forty asteroids from ADAM shape modeling. Astronomy and Astrophysics 601, A114 (2017). DOI: 10.1051/0004-6361/201629956

Mass estimates

DesignationMass / Err (kg)ΔM/MMethodYearRefNχ2Use
(89) Julia7.14e+18 (+2.78e+17 / -2.78e+17)4 % / 4 %Ephem 2009M8020.40 1
(89) Julia8.32e+18 (+4.14e+18 / -4.14e+18)50 % / 50 %Ephem 2010M930.11 2
(89) Julia3.72e+17 (+3.24e+18 / -3.24e+18)871 % / 871 %Deflec 2011M974.14 3
(89) Julia8.55e+18 (+5.97e+17 / -5.97e+17)7 % / 7 %OrbFitN 2014M1237.06 4
(89) Julia3.74e+18 (+8.94e+17 / -8.94e+17)24 % / 24 %Ephem 2019M12612.98 5
(89) Julia1.83e+19 (+1.85e+19 / -1.31e+19)101 % / 72 %Defl-MC 2020M12820.51 6

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).
4: Values with asymmetric errors are currently just diplayed but disabled (unchecked) for the average calculation.

Defl-MC : Orbital deflection (close encounter) of one or several test asteroids (Markov Chain Monte Carlo, MCMC). Deflec : Orbital deflection (close encounter) of one or several test asteroids (classical LSQ). Ephem : Planetary ephemeris solution. OrbFitN : Simultaneous multi-asteroid astrometric orbit solution (similar to 'Ephem').


EVM mass average M = (6.964 ± 2.264) × 1018 kg   (ΔM/M = 33%, SNR = 3.1) Derived bulk density ρ = (9.77 ± 4.44) g/cm3   (Δρ/ρ = 45%, SNR = 2.2)


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.
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.
M123(2014):Goffin, E., 2014. Astrometric asteroid masses: a simultaneous determination. Astronomy & Astrophysics, Volume 565, id.A56, 8 pp.
M126(2019):Fienga, A., et. al, 2019. INPOP19a planetary ephemeris. Notes Scientifiques et Techniques de l'Institut de mécanique céleste,
M128(2020):Siltala, L., Granvik, M., 2020. Asteroid mass estimation with the robust adaptive Metropolis algorithm. Astronomy & Astrophysics, 633, A46.