J/A+A/695/A139 Spins and shapes of 11 NEAs (Fatka+, 2025)
Spins and shapes of 11 near-Earth asteroids observed within the
NEOROCKS Project.
Fatka P., Pravec P., Scheirich P., Kusnirak P., Hornoch K., Kucakova H.,
Ergashev K.E., Souza de Joode M., Burkhonov O.A., Ehgamberdiev S.A.,
Galad A., Vilagi J., Reddy V., Dyvig R., Ries J.G., Snodgrass C.,
Donaldson A., Peixinho N., Khalouei E.
<Astron. Astrophys. 695, A139 (2025)>
=2025A&A...695A.139F 2025A&A...695A.139F (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Minor planets ; Photometry, CCD
Keywords: methods: data analysis - methods: observational -
minor planets, asteroids: individual: near-Earth asteroids
Abstract:
The discovery rate of near-Earth asteroids (NEAs) has steadily
increased over the past three decades, yet the physical
characterization of these objects has not kept pace.
In an effort to help address this gap, we combined targeted
photometric observations, archival data, and sparse photometric data
from the ATLAS survey to extract maximum information about NEAs'
rotation rates, spin-axis orientations, and shapes.
We selected 17 NEAs with a potential for shape reconstruction and
applied the lightcurve inversion method to derive their sidereal
rotation periods, spin-axis directions, and convex shape models.
We successfully determined unique spin and shape models for seven
NEAs: (5189) 1990 UQ, (6569) Ondaatje, (7025) 1993 QA, (8566) 1996 EN,
(86450) 2000 CK33, the Hayabusa2# flyby target (98943) 2001 CC21,
and (512245) 2016 AU8. For additional four asteroids' (66251) 1999
GJ2, (137199) 1999 KX4, (276786) 2004 KD1, and (495615) 2015
PQ291 - we constrained their sidereal periods, spin-axis
orientations, and in some cases, their shapes.
This study highlights the importance of integrating new photometric
data with archival dense lightcurves and sparse observations to
improve the physical characterization of NEAs, even when working with
suboptimal datasets. We constructed 11 NEA models, contributing to the
limited set of a few dozen models derived from space missions, radar
observations, and lightcurve inversions.
Description:
Directory "lcs" contains a subdirectory for each asteroid we attempted
to model. Each sub-directory contains all new lightcurves for given
asteroid. These lightcurves come from several telescopes and reported
magnitude uncertainties are formal. Magnitude uncertainties may be
missing for old observations. Observation in a single session (during
one night from one telescope) may be split into several files if
asteroid's apparent motion was high and more than one set of
comparison stars had to used for photometric reduction.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 69 95 Observational circumstances of studied asteroids
tablea2.dat 75 22 Overview of the modelling results
tablea3.dat 128 17 Summary of asteroids observation circumstances
and success rate in modelling
lcs/* . 17 Sub-directories with light curves
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See also:
B/astorb : Orbits of Minor Planets (Bowell+, 2014-)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Name ? Designation number of asteroid (if available)
8- 16 A9 --- AName Alternative/temporary asteroid designation
18- 27 A10 "date" Date-init Beginning of observing run series (DD-MM-YYYY)
29- 38 A10 "date" Date-end End of observing run series (DD-MM-YYYY)
40- 41 I2 --- Nsessions Number of observing sessions in the date span
43- 45 I3 deg PA-init Phase angle corresponding to date_init
47- 49 I3 deg PA-end Phase angle corresponding to date_fin
51- 65 A15 --- Inst Instrument
68- 69 I2 --- Ref ? Source of the data (1)
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Note (1): References as follows:
1 = Oey (2020, Minor Planet Bull., 47, 136)
2 = ATLAS, Tonry et al., 2018PASP..130f4505T 2018PASP..130f4505T
3 = Warner (2018, Minor Planet Bull., 45, 138)
4 = Warner & Stephens (2019, Minor Planet Bull., 46, 304)
5 = Warner et al. (2021, Minor Planet Bull., 48, 337)
6 = Pravec et al. (1996, Icarus, 124, 471)
7 = Waszczak et al. (2015AJ....150...75W 2015AJ....150...75W, Cat. J/5AJ/150/75)
8 = Warner & Stephens (2020, Minor Planet Bull., 47, 290)
9 = Schmalz et al. (2023, Minor Planet Bull., 50, 43)
10 = Warner & Stephens (2022, Minor Planet Bull., 49, 274)
11 = Krugly et al. (2002, Icarus, 158, 294)
12 = Pravec et al. (1998, Icarus, 136, 124)
13 = Franco et al. (2022, Minor Planet Bull., 49, 200)
14 = Warner & Stephens (2020, Minor Planet Bul., 47, 200)
15 = Warner (2015, Minor Planet Bull., 42, 172)
16 = Warner & Stephens (2022, Minor Planet Bull., 49, 176)
17 = Polishook (2012, Minor Planet Bull., 39, 187)
18 = Polishook & Brosch (2008, Icarus, 194, 111)
19 = Ries & Varadi (2007, in AAS/Division for Planetary Sciences Meeting 6
Abstracts, 39, AAS/Division for Planetary sciences Meeting Abstracts
#39, 35.16)
20 = Warner (2013, Minor Planet Bull., 40, 137)
21 = Carbognani (2014, Minor Planet Bull., 41, 4)
22 = Warner & Stephens (2020, Minor Planet Bull., 47, 105)
23 = Benishek (2021, Minor Planet Bull., 48, 77)
24 = Carbognani (2008, Minor Planet Bull., 35, 109)
25 = Warner (2014, Minor Planet Bull., 41, 41)
26 = Vaduvescu et al. (2022, Earth, Moon and Planets, 126, 6)
27 = Warner & Stephens (2019, Minor Planet Bull., 46, 144)
28 = Thirouin et al. (2016AJ....152..163T 2016AJ....152..163T, Cat. J/AJ/152/163)
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Name ? Designation number of asteroid (if available)
8- 16 A9 --- AName Alternative/temporary name of asteroid
18- 20 I3 --- Nper Number of possible sidereal periods
22 I1 --- Npole ?=- Number of possible rotational pole
directions
24- 32 F9.6 h Psid Best-fit sidereal period
34- 41 F8.6 h E_Psid Upper uncertainty of Psid (3 sigma)
43- 50 F8.6 h e_Psid Lower uncertainty of Psid (3 sigma)
52- 54 I3 deg lambda ?=- Ecliptic longitude
56- 58 I3 deg beta ?=- Ecliptic latitude
60- 61 I2 deg e_rpole ?=- Radius of pole uncertainty
63- 65 I3 deg epsilon ?=- Obliquity
67- 70 F4.2 deg a/b ?=- a/b axis ratios of surface-fit ellipsoids
72- 75 F4.2 deg a/c ?=- a/c axis ratios of surface-fit ellipsoids
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Name ? Designation number of asteroid (if available)
8- 16 A9 --- AName Alternative/temporary name of asteroid
18- 22 F5.2 h Psid Rough best-fit sidereal period
24- 26 I3 --- Nper Number of possible sidereal periods
28 I1 - Npole ?=- Number of possible rotational pole
directions
30- 33 F4.1 yr App-gap12 Gaps between apparitions 1 and 2
34 A1 --- --- [/]
35- 38 F4.1 yr App-gap23 ? Gaps between apparitions 2 and 3
39 A1 --- --- [/]
40- 42 F3.1 yr App-gap34 ? Gaps between apparitions 3 and 4
43 A1 --- --- [/]
44- 46 F3.1 yr App-gap45 ? Gaps between apparitions 4 and 5
47 A1 --- --- [/]
48- 50 F3.1 yr App-gap56 ? Gaps between apparitions 5 and 6
52- 55 I4 --- App-pts1 Number of data points for apparition 1
56 A1 --- --- [/]
57- 60 I4 --- App-pts2 Number of data points for apparition 2
61 A1 --- --- [/]
62- 64 I3 --- App-pts3 ? Number of data points for apparition 3
65 A1 --- --- [/]
66- 68 I3 --- App-pts4 ? Number of data points for apparition 4
69 A1 --- --- [/]
70- 72 I3 --- App-pts5 ? Number of data points for apparition 5
73 A1 --- --- [/]
74- 76 I3 --- App-pts6 ? Number of data points for apparition 6
78- 79 I2 % PABcov Phase angle bi-sector coverage
81- 84 F4.2 mag lcampl Observed lightcurve amplitude
86 I1 --- Rating [0/2] Rating of model successfulness (1)
88-116 A29 --- Comment Brief evaluation of model successfulness
118-125 A8 --- FileName Name of the directory with light curves
127-128 I2 --- Nfiles Number of files in the subdirectory
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Note (1): Rating model code as follows:
0 = full model, period, pole and shape well constrained
1 = partially successfully model, ambiguity in period or pole
2 = unsuccessful model, too many period aliases
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Byte-by-byte Description of file: lcs/*/*
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Bytes Format Units Label Explanations
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1- 13 F13.5 d JD Julian date (UT), no light-time correction
15- 20 F6.3 mag mag Relative brightness of target
22- 27 F6.3 mag e_mag ?=- Formal uncertainty of asteroid brightness
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Acknowledgements:
Petr Fatka, petr.fatka(at)asu.cas.cz
(End) Patricia Vannier [CDS] 18-Feb-2025