J/AJ/134/1133 Fraction of contact binary trojan asteroids (Mann+, 2007)
Fraction of contact binary trojan asteroids.
Mann R.K., Jewitt D., Lacerda P.
<Astron. J., 134, 1133-1144 (2007)>
=2007AJ....134.1133M 2007AJ....134.1133M
ADC_Keywords: Surveys ; Planets
Keywords: minor planets, asteroids - solar system: general - surveys
Abstract:
We present the results of an optical light-curve survey of 114 Jovian
Trojan asteroids conducted to determine the fraction of contact
binaries. Sparse sampling was used to assess the photometric range of
the asteroids, and those showing the largest ranges were targeted for
detailed follow-up observations. This survey led to the discovery of
two Trojan asteroids, (17365) and (29314), displaying large
light-curve ranges (∼1mag) and long rotation periods (<2rotations/day)
consistent with a contact binary nature.
Description:
We obtained sparsely sampled optical light-curve data for the Jovian
Trojan asteroids using both the University of Hawaii (UH) 2.2m
telescope on Mauna Kea and the Lulin 1m Telescope (LOT) in Taiwan,
between 2005 Mar 7 and 2006 May 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 62 114 Photometry of Jovian Trojan asteroids
table3.dat 45 114 Geometric and photometric properties of Jovian
Trojan asteroids
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See also:
B/astorb : Orbits of Minor Planets (Bowell+ 2009)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Num ? Planet number
7- 17 A11 --- Name Trojan name
19- 21 A3 --- Tel Telescope used in observation (1)
23- 27 F5.2 mag RMAG Mean absolute R band magnitude
29- 33 F5.2 mag R1-R First R band magnitude minus Mean R band magnitude
35- 39 F5.2 mag R2-R Second R band magnitude minus Mean R band magnitude
41- 45 F5.2 mag R3-R Third R band magnitude minus Mean R band magnitude
47- 51 F5.2 mag R4-R Fourth R band magnitude minus Mean R band magnitude
53- 57 F5.2 mag R5-R ? Fifth R band magnitude minus Mean R band magnitude
59- 62 F4.2 mag DelR Photometric range in the R band
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Note (1): Telescope as follows:
UH = University of Hawaii 2.2-m telescope
LOT = Taiwan Lulin One-meter Telescope
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Num ? Planet number
7- 17 A11 --- Name Trojan name
19- 23 F5.2 mag MAG Absolute magnitude (1)
25- 28 F4.2 AU Hdist Heliocentric distance
30- 33 F4.2 AU Gdist Geocentric distance
35- 38 F4.1 deg alpha Phase angle
40- 42 I3 km De Effective diameter (2)
44- 45 A2 --- L4/L5 The L4 or L5 location
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Note (1): From equation
mR(1,1,0)=mR-5log(r{DELTA})-βα,
where α is the phase coefficient for which we used a value of
0.04mag/deg for the low-albedo Trojan asteroids.
Note (2): From equation
mR(1,1,0)=m☉-2.5log(p(De)2/(4*2.25*106))
where p is the geometric albedo, for which a value of 0.04
and m☉-27.1 is the apparent red magnitude of the Sun.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 03-Oct-2009