J/ApJ/741/68 Main Belt asteroids with WISE/NEOWISE. I. (Masiero+, 2011)
Main Belt asteroids with WISE/NEOWISE.
I. Preliminary albedos and diameters.
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.
<Astrophys. J., 741, 68 (2011)>
=2011ApJ...741...68M 2011ApJ...741...68M
ADC_Keywords: Minor planets ; Infrared sources ; Surveys
Keywords: infrared: general - minor planets, asteroids: general
Abstract:
We present initial results from the Wide-field Infrared Survey
Explorer (WISE), a four-band all-sky thermal infrared survey that
produces data well suited for measuring the physical properties of
asteroids, and the NEOWISE enhancement to the WISE mission allowing
for detailed study of solar system objects. Using a NEATM thermal
model fitting routine, we compute diameters for over 100000 Main Belt
asteroids (MBAs) from their IR thermal flux, with errors better than
10%. We then incorporate literature values of visible measurements (in
the form of the H absolute magnitude) to determine albedos. Using
these data we investigate the albedo and diameter distributions of the
Main Belt. As observed previously, we find a change in the average
albedo when comparing the inner, middle, and outer portions of the
Main Belt. We also confirm that the albedo distribution of each region
is strongly bimodal. We observe groupings of objects with similar
albedos in regions of the Main Belt associated with dynamical breakup
families. Asteroid families typically show a characteristic albedo for
all members, but there are notable exceptions to this.
Description:
Launched on 2009 December 14, WISE is a thermal infrared space
telescope that performed an all-sky survey from 2010 January 14 until
it exhausted the telescope-cooling hydrogen ice on 2010 August 5. The
survey continued during the warm-up of this secondary tank with
limited sensitivity in the longer wavelengths until the primary
coolant, responsible for maintaining detector temperature, was
exhausted on 2010 October 1. WISE subsequently entered a
Post-Cryogenic Mission to complete the survey of the largest MBAs,
continue discovering new near-Earth objects (NEOs), and complete a
second-pass survey of the inertial sky in the two shortest
wavelengths. During its cryogenic mission, WISE imaged the sky in four
infrared wavelengths simultaneously using dichroic beam splitters to
produce co-boresight images with band centers at 3.4um, 4.6um, 12um,
and 22um (W1, W2, W3, and W4, respectively).
In this paper, we consider only those MBAs detected by NEOWISE/WMOPS
during the cryogenic portion of the mission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 95 139480 *Thermal model fits for Main Belt Asteroids (MBA)
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Note on table1.dat: This table contains the preliminary thermal fit results
based on the First Pass version of the WISE data processing as described in
the text. The NEOWISE project plans to produce an updated final catalog of
physical properties based on the Second Pass processing of the WISE data using
the updated version of the WISE Science Data System, with a goal of delivering
this updated catalog to NASA's Planetary Data System.
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See also:
B/astorb : Orbits of Minor Planets (Bowell+ 2013)
II/190 : IRAS Minor Planet Survey (IMPS) (Tedesco 1992)
VII/91 : IRAS Asteroid and Comet Survey (Veeder+ 1986)
J/A+A/542/A11 : Main-belt asteroids polarimetry. III (Canada-Assandri+, 2012)
J/A+A/545/A131 : Photometry of 8 main belt asteroids (Marciniak+, 2012)
J/A+A/529/A86 : Polarimetric survey of main-belt asteroids (Gil-Hutton+, 2011)
J/A+A/529/A107 : Photometry of 4 main belt asteroids (Marciniak+, 2011)
J/A+A/498/313 : Photometry of 3 main belt asteroids (Marciniak+, 2009)
J/A+A/423/381 : Asteroidal I, J, K in the DENIS Survey (Baudrand+, 2004)
J/AJ/123/2070 : ISO deep asteroid search (Tedesco+, 2002)
J/A+A/375/275 : Asteroidal I, J, K in the DENIS Survey (Baudrand+ 2001)
http://www.minorplanetcenter.net/ : Minor Planet Center home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- MPC Asteroid name, in MPC packed format
9- 14 F6.3 mag HMag [4.06/19.8]?=-9.99 Absolute H band magnitude
16- 20 F5.2 --- G ?=-9.99 Magnitude slope parameter
22- 28 F7.3 km Diam [0.4/544] Asteroid diameter
30- 35 F6.3 km e_Diam Statistical error in Diam (1)
37- 43 F7.4 --- pV [0/1]?=-9.99 Visible geometrical albedo
45- 51 F7.4 --- e_pV ?=-9.99 Statistical error in pV (1)
53- 57 F5.3 --- eta Beaming parameter η (3)
59- 64 F6.3 --- e_eta ?=-9.99 Statistical error in eta (2)
66- 72 F7.4 --- pIR [0/1]?=-9.99 Infra-red geometrical albedo
74- 80 F7.4 --- e_pIR ?=-9.99 Statistical error in pIR (1)
82- 83 I2 --- N1 Number of WISE W1 (3.3um) observations
85- 87 I3 --- N2 Number of WISE W2 (4.6um) observations
89- 91 I3 --- N3 Number of WISE W3 (11.6um) observations
93- 95 I3 --- N4 Number of WISE W4 (22.1um) observations
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Note (1): Error values presented here represent the statistical errors on
the model fits, including Monte Carlo modeling of uncertainties for
the WISE magnitudes, H, G, and beaming and pIR when these two
parameters cannot be fit. Two calibration papers by Mainzer et al,
(2011ApJ...736..100M 2011ApJ...736..100M and 2011ApJ...737L...9M 2011ApJ...737L...9M) discuss the absolute
calibration of the WISE data for small Solar system bodies and should
be consulted before comparing with data derived from other sources.
The quoted precision for each parameter follows the object with the
most significant figures for the error on that value in the table.
H, G and albedo values of "-9.99" indicate that the objects have not
received visible light follow-up. Readers are encouraged to check the
WISE Explanatory Supplement by Cutri et al. 2011,
http://wise2.ipac.caltech.edu/docs/release/prelim/expsup/wise_prelrel_toc.html
for details and updates.
Note (2): Beaming value errors of "-9.99" indicate that the thermal fit
routine returned a maximum value of π or a minimum of 0.3, so
error cannot be properly determined.
Note (3): The beaming parameter η represents the deviation of the
thermal emission from that of a smooth non-rotating sphere due to
rotation and surface roughness, and is used to consolidate the
uncertainty in the values of the surface thermal properties, including
emissivity; in range [0,π].
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History:
From electronic version of the journal
References:
Masiero et al. 2012ApJ...759L...8M 2012ApJ...759L...8M
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 21-Feb-2013