SiMDA»Main

Summary for : (8) Flora

Dyn	T.T	T.B	T T.L B	T.D	Density (g/cm^3)	Δρ/ρ	Diameter (km)	ΔD/D	Mass (kg)	ΔM/M	Ref	Avg.M
MBA	S	-	- \| -	Sw	5.27 ± 1.64 (C)	31 %	138.8 ± 4.8	3.5 %	7.38e+18 ± 2.17e+18	29 %	S	EVM
MBA	S	-	- \| -	Sw	6.94 ± 1.43 (C)	21 %	137.1 ± 5.0	3.6 %	9.37e+18 ± 1.63e+18	17 %	S	w.avg
MBA	S				6.50 ± 1.28 (X)	20 %	139.1 ± 2.3	1.6 %	9.17e+18 ± 1.75e+18	19 %	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

Designation	Diameter / Err (km)	ΔD/D	Method	Year	Ref	N	χ²	Use
(8) Flora	135.88 ± 2.29	1.7 %	STM	2004	D93	2	1.63	1
(8) Flora	115.77 ± 2.65	2.3 %	STM	2010	D64	2	75.55	2
(8) Flora	145.76 ± 7.06	4.8 %	NEATM	2010	D64		0.97	3
(8) Flora	141.00 ± 10.00	7.1 %	MDM:LO	2011	D78		0.05	4
(8) Flora	140.00 ± 7.00	5.0 %	MDM:LO	2011	D78		0.03	5
(8) Flora	138.30 ± 1.37	1.0 %	STM	2011	D83		0.14	6
(8) Flora	140.00 ± 1.15	0.8 %	NEATM	2011	D72		1.08	7
(8) Flora	140.00 ± 4.00	2.9 %	ADAM	2017	D100		0.09	8

plot, average diameter and derived density

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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 = (138.8 ± 4.82) km (ΔD/D = 3%, SNR = 28.80) Derived bulk density ρ = (5.27 ± 1.64) g/cm³ (Δρ/ρ = 31%, SNR = 3.2)

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.
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

Designation	Mass / Err (kg)	ΔM/M	Method	Year	Ref	N	χ²	Use
(8) Flora	8.47e+18 ± 8.95e+17	11 %	Deflec	2008	M72	2	1.47	1
(8) Flora	1.06e+19 ± 9.95e+16	1 %	Ephem	2009	M80	2	1044.80	2
(8) Flora	3.54e+18 ± 3.54e+17	10 %	Ephem	2009	M86	1	117.90	3
(8) Flora	8.10e+18 ± 1.26e+18	16 %	Ephem	2010	M93	2	0.32	4
(8) Flora	6.62e+18 ± 8.35e+17	13 %	Deflec	2011	M95	2	0.84	5
(8) Flora	4.00e+18 ± 8.35e+17	21 %	Ephem	2011	M103	1	16.42	6
(8) Flora	8.44e+18 ± 1.49e+18	18 %	Deflec	2011	M97	2	0.50	7
(8) Flora	6.03e+18 ± 1.29e+18	21 %	Deflec	2011	M97	2	1.10	8
(8) Flora	7.35e+18 ± 1.31e+18	18 %	Deflec	2011	M97	2	0.00	9
(8) Flora	6.75e+18 ± 2.06e+18	31 %	Deflec	2011	M97	2	0.09	10
(8) Flora	6.66e+18 ± 5.97e+17	9 %	Ephem	2011	M100	2	1.47	11
(8) Flora	5.77e+18 ± 3.98e+17	7 %	OrbFitN	2014	M123	2	16.50	12
(8) Flora	9.31e+18 ± 8.75e+17	9 %	Deflec	2017	M125	2	4.83	13
(8) Flora	9.72e+18 ± 1.28e+18	13 %	Deflec	2017	M125	2	3.34	14
(8) Flora	9.44e+18 ± 7.22e+17	8 %	Deflec	2017	M125	32	8.15	15
(8) Flora	4.01e+18 ± 4.23e+17	11 %	Ephem	2019	M126		63.58	16

plot, average mass and derived density

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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 = (7.384 ± 2.167) × 10¹⁸ kg (ΔM/M = 29%, SNR = 3.4) Derived bulk density ρ = (5.27 ± 1.64) g/cm³ (Δρ/ρ = 31%, SNR = 3.2)

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.
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,

Size, Mass and Density of Asteroids (SiMDA)

Summary for : (8) Flora

Diameter estimates

Mass estimates