Summary for : (14) Irene

DynT.TT.BT T.L B T.DDensity (g/cm^3)Δρ/ρDiameter (km)ΔD/DMass (kg)ΔM/MRefAvg.M
MBASS- | -S2.72 ± 1.65   (D)61 %147.5 ± 5.23.5 %4.57e+18 ± 2.73e+1860 %SEVM
MBASS- | -S1.56 ± 6.17   (E)397 %145.9 ± 6.84.7 %2.53e+18 ± 1.00e+19396 %Sw.avg
MBAS1.72 ± 1.12   (D)65 %147.8 ± 5.03.4 %2.91e+18 ± 1.88e+1865 %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
(14) Irene144.08 ± 1.941.3 % TPM2011D83 3.13 1
(14) Irene155.39 ± 4.382.8 % NEATM2011D72 3.23 2

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).

NEATM : Near-Earth Asteroid Thermal Model. TPM : Thermophysical Model.


EVM diam. average D = (147.5 ± 5.20) km   (ΔD/D = 4%, SNR = 28.36) Derived bulk density ρ = (2.72 ± 1.65) g/cm3   (Δρ/ρ = 61%, SNR = 1.6)


References
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.
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
(14) Irene8.21e+18 ± 1.45e+1818 %Deflec 2008M7216.30 1
(14) Irene1.41e+18 ± 1.99e+1714 %Ephem 2009M802252.21 2
(14) Irene5.21e+18 ± 5.21e+1710 %Ephem 2009M861.51 3
(14) Irene5.12e+19 ± 1.59e+1931 %Deflec 2010M92128.60 4
(14) Irene6.94e+18 ± 1.63e+1823 %Deflec 2011M952.11 5
(14) Irene3.80e+18 ± 1.61e+1842 %Ephem 2011M1030.23 6
(14) Irene4.81e+18 ± 2.85e+1859 %Deflec 2011M970.01 7
(14) Irene2.79e+18 ± 2.02e+1872 %Deflec 2011M970.78 8
(14) Irene1.93e+18 ± 2.00e+18104 %Deflec 2011M971.74 9
(14) Irene1.69e+19 ± 5.28e+1831 %Deflec 2011M97125.45 10
(14) Irene5.57e+18 ± 5.97e+1711 %OrbFitN 2014M1232.79 11
(14) Irene5.14e+18 ± 7.91e+1715 %Ephem 2019M1260.52 12

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. OrbFitN : Simultaneous multi-asteroid astrometric orbit solution (similar to 'Ephem').


EVM mass average M = (4.570 ± 2.733) × 1018 kg   (ΔM/M = 60%, SNR = 1.7) Derived bulk density ρ = (2.72 ± 1.65) g/cm3   (Δρ/ρ = 61%, SNR = 1.6)


References
M72(2008):Baer, J., Milani, A., Chesley, S.R., Matson, R.D., 2008. An Observational Error Model, and Application to Asteroid Mass Determination, in: Bulletin of the American Astronomical Society, p. 493.
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.
M92(2010):Somenzi, L., Fienga, A., Laskar, J., Kuchynka, P., 2010. Determination of asteroid masses from their close encounters with Mars. Planetary and Space Science 58, 858–863.
M95(2011):Baer, J., Chesley, S.R., Matson, R.D., 2011. Astrometric Masses of 26 Asteroids and Observations on Asteroid Porosity. Astronomical Journal 141, 143–155.
M97(2011):Zielenbach, W., 2011. Mass Determination Studies of 104 Large Asteroids. Astronomical Journal 142, 120–128.
M103(2011):Konopliv, A.S., Asmar, S.W., Folkner, W.M., Karatekin, Ö., Nunes, D.C., Smrekar, S.E., Yoder, C.F., Zuber, M.T., 2011. Mars high resolution gravity fields from MRO, Mars seasonal gravity, and other dynamical parameters. Icarus 211, 401–428.
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,