Summary for : (7) Iris

DynT.TT.BT T.L B T.DDensity (g/cm^3)Δρ/ρDiameter (km)ΔD/DMass (kg)ΔM/MRefAvg.M
MBASS- | -S2.83 ± 1.23   (C)43 %213.7 ± 22.910.7 %1.45e+19 ± 4.18e+1829 %SEVM
MBASS- | -S1.69 ± 0.72   (C)43 %242.5 ± 17.57.2 %1.26e+19 ± 4.65e+1837 %Sw.avg
MBAS2.14 ± 0.81   (C)38 %225.9 ± 25.911.5 %1.29e+19 ± 2.10e+1816 %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
(7) Iris199.83 ± 10.005.0 % STM2004D93 1.92 1
(7) Iris223.30 ± 37.2916.7 % Radar2010D69 0.07 2
(7) Iris190.46 ± 11.456.0 % STM2010D64 4.11 3
(7) Iris226.37 ± 10.944.8 % NEATM2010D64 1.35 4
(7) Iris198.00 ± 27.0013.6 % MDM:LO2011D78 0.34 5
(7) Iris199.00 ± 26.0013.1 % MDM:LO2011D78 0.32 6
(7) Iris254.19 ± 3.261.3 % STM2011D832 154.44 7

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. Radar : Radar imaging. STM : Standard Thermal Model.


EVM diam. average D = (213.7 ± 22.92) km   (ΔD/D = 11%, SNR = 9.32) Derived bulk density ρ = (2.83 ± 1.23) g/cm3   (Δρ/ρ = 43%, SNR = 2.3)


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.
D69(2010):Ostro, S.J., Magri, C., Benner, L.A.M., Giorgini, J.D., Nolan, M.C., Hine, A.A., Busch, M.W., Margot, J.L., 2010. Radar imaging of Asteroid 7 Iris. Icarus 207, 285–294.
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
(7) Iris3.98e+19 (+1.79e+19 / -1.79e+19)45 % / 45 %Deflec 1999M18122.00 1
(7) Iris1.19e+19 (+1.99e+18 / -1.99e+18)17 % / 17 %Deflec 2001M281.67 2
(7) Iris2.80e+19 (+2.78e+18 / -2.78e+18)10 % / 10 %Deflec 2002M311223.68 3
(7) Iris2.80e+19 (+2.78e+18 / -2.78e+18)10 % / 10 %Deflec 2004M421223.68 4
(7) Iris1.03e+19 (+1.59e+18 / -1.59e+18)15 % / 15 %Deflec 2004M396.88 5
(7) Iris1.25e+19 (+1.99e+17 / -1.99e+17)2 % / 2 %Deflec 2005M49298.10 6
(7) Iris1.79e+19 (+1.99e+18 / -1.99e+18)11 % / 11 %Ephem 2007M622.97 7
(7) Iris1.36e+19 (+9.94e+17 / -9.94e+17)7 % / 7 %Deflec 2008M720.77 8
(7) Iris4.77e+19 (+5.97e+18 / -5.97e+18)13 % / 13 %Deflec 2008M781230.98 9
(7) Iris1.15e+19 (+1.99e+17 / -1.99e+17)2 % / 2 %Ephem 2008M702222.89 10
(7) Iris1.19e+19 (+1.19e+18 / -1.19e+18)10 % / 10 %Ephem 2009M864.67 11
(7) Iris1.55e+19 (+2.27e+18 / -2.27e+18)15 % / 15 %Ephem 2010M930.21 12
(7) Iris1.62e+19 (+9.15e+17 / -9.15e+17)6 % / 6 %Deflec 2011M953.57 13
(7) Iris1.10e+19 (+2.63e+18 / -2.63e+18)24 % / 24 %Ephem 2011M1031.74 14
(7) Iris1.75e+19 (+1.88e+18 / -1.88e+18)11 % / 11 %Deflec 2011M972.60 15
(7) Iris1.72e+19 (+1.60e+18 / -1.60e+18)9 % / 9 %Deflec 2011M972.91 16
(7) Iris1.68e+19 (+1.59e+18 / -1.59e+18)9 % / 9 %Deflec 2011M972.15 17
(7) Iris2.33e+19 (+3.12e+18 / -3.12e+18)13 % / 13 %Deflec 2011M97128.01 18
(7) Iris1.13e+19 (+7.96e+17 / -7.96e+17)7 % / 7 %Ephem 2011M10015.87 19
(7) Iris1.39e+19 (+3.98e+17 / -3.98e+17)3 % / 3 %OrbFitN 2014M1231.92 20
(7) Iris2.19e+19 (+1.85e+18 / -1.85e+18)8 % / 8 %Deflec 2017M125216.00 21
(7) Iris1.52e+19 (+1.87e+18 / -1.87e+18)12 % / 12 %Deflec 2017M12520.13 22
(7) Iris2.19e+19 (+2.94e+18 / -2.94e+18)13 % / 13 %Deflec 2017M12526.33 23
(7) Iris3.28e+19 (+4.49e+18 / -4.49e+18)14 % / 14 %Deflec 2017M125216.68 24
(7) Iris1.17e+19 (+1.70e+18 / -1.70e+18)14 % / 14 %Deflec 2017M12522.60 25
(7) Iris1.04e+19 (+2.23e+18 / -2.23e+18)21 % / 21 %Deflec 2017M12523.33 26
(7) Iris2.96e+19 (+6.92e+18 / -6.92e+18)23 % / 23 %Deflec 2017M12524.80 27
(7) Iris1.65e+19 (+4.16e+18 / -4.16e+18)25 % / 25 %Deflec 2017M12520.23 28
(7) Iris1.98e+19 (+5.69e+18 / -5.69e+18)29 % / 29 %Deflec 2017M12520.86 29
(7) Iris2.52e+19 (+9.62e+18 / -9.62e+18)38 % / 38 %Deflec 2017M12521.26 30
(7) Iris1.63e+19 (+7.36e+18 / -7.36e+18)45 % / 45 %Deflec 2017M12520.06 31
(7) Iris1.41e+19 (+6.68e+18 / -6.68e+18)47 % / 47 %Deflec 2017M12520.00 32
(7) Iris1.66e+19 (+8.29e+17 / -8.29e+17)5 % / 5 %Deflec 2017M12536.47 33
(7) Iris4.18e+18 (+2.86e+18 / -3.18e+18)68 % / 76 %Defl-MC 2017M127211.61 34
(7) Iris1.23e+19 (+5.68e+17 / -5.68e+17)5 % / 5 %Ephem 2019M12614.34 35
(7) Iris6.28e+18 (+2.41e+18 / -2.43e+18)38 % / 39 %Defl-MC 2020M128211.46 36
(7) Iris1.24e+19 (+3.08e+18 / -3.18e+18)25 % / 26 %Defl-MC 2020M1280.44 37

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 = (1.447 ± 0.418) × 1019 kg   (ΔM/M = 29%, SNR = 3.5) Derived bulk density ρ = (2.83 ± 1.23) g/cm3   (Δρ/ρ = 43%, SNR = 2.3)


References
M18(1999):Vasiliev, M.V., Yagudina, E.I., 1999. Determination of masses for 26 selected minor planets from analysis of observations their mutual encounters with asteroids of lesser mass, in: Communications of IAA of RAS.
M28(2001):Krasinsky, G.A., Pitjeva, E.V., Vasiliev, M.V., Yagudina, E.I., 2001. Estimating masses of asteroids, in: Communications of IAA of RAS.
M31(2002):Chernetenko, Y.A., Kochetova, O.M., 2002. Masses of some large minor planets, in: B. Warmbein (Ed.), Asteroids, Comets, and Meteors: ACM 2002, pp. 437–440.
M39(2004):Pitjeva, E.V., 2004. Estimations of masses of the largest asteroids and the main asteroid belt from ranging to planets, Mars orbiters and landers, in: J.-P. Paillé (Ed.), 35th COSPAR Scientific Assembly, p. 2014.
M42(2004):Kochetova, O.M., 2004. Determination of Large Asteroid Masses by the Dynamical Method. Solar System Research 38, 66–75.
M49(2005):Pitjeva, E.V., 2005. High-Precision Ephemerides of Planets - EPM and Determination of Some Astronomical Constants. Solar System Research 39, 176–186.
M62(2007):Aslan, Z., Gumerov, R., Hudkova, L., Ivantsov, A., Khamitov, I., Pinigin, G., 2007. Mass Determination of Small Solar System Bodies with Ground-based Observations, in: O. Demircan, S. O. Selam, & B. Albayrak (Ed.), Solar and Stellar Physics Through Eclipses, pp. 52–58.
M70(2008):Fienga, A., Manche, H., Laskar, J., Gastineau, M., 2008. INPOP06: a new numerical planetary ephemeris. Astronomy and Astrophysics 477, 315–327.
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.
M78(2008):Ivantsov, A., 2008. Asteroid mass determination at Nikolaev Observatory. Planetary and Space Science 56, 1857–1861.
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.
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.
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.
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.
M125(2017):Baer, J., Chesley, S.R., 2017. Simultaneous Mass Determination for Gravitationally Coupled Asteroids. The Astronomical Journal, Volume 154, Issue 2, article id. 76, 11 pp.
M126(2019):Fienga, A., et. al, 2019. INPOP19a planetary ephemeris. Notes Scientifiques et Techniques de l'Institut de mécanique céleste,
M127(2017):Siltala, L., Granvik, M., 2017. Asteroid mass estimation using Markov-chain Monte Carlo. Icarus 297 (November 2017), 149-159. https://doi.org/10.1016/j.icarus.2017.06.028
M128(2020):Siltala, L., Granvik, M., 2020. Asteroid mass estimation with the robust adaptive Metropolis algorithm. Astronomy & Astrophysics, 633, A46.