J/A+A/680/A41 Potentially hazardous asteroids observations (Perlbarg+, 2023)
NAROO program. Precovery observations of potentially hazardous asteroids.
Perlbarg A.-C., Desmars J., Robert V., Hestroffer D.
<Astron. Astrophys. 680, A41 (2023)>
=2023A&A...680A..41P 2023A&A...680A..41P (SIMBAD/NED BibCode)
ADC_Keywords: Minor planets ; Plate data ; Positional data ; Optical
Keywords: minor planets, asteroids: general -
astronomical databases: miscellaneous - astrometry - ephemerides
Abstract:
The New Astrometric Reduction of Old Observations (NAROO) program is
dedicated to the measurement of astrophotographic plates and the
analysis of old observations for scientific purposes. One of the
objectives of the NAROO program is to provide accurate positional
measurements of small Solar System bodies in order to improve our
knowledge of their orbits and dynamics.
Focused on potentially hazardous asteroids (PHAs), which are
near-Earth asteroids (NEAs) making very close encounters with the
Earth, this paper aims to emphasize the value of old photographic
plate observations. As they provide accurate astrometric measurements
over a large time interval, such observations are essential to
determine reliable orbits and to detect small accelerations, such as
the Yarkovsky effect.
Photographic plates consist of a substantial source of old
observations of Solar System objects.From existing databases, we
identified old and precovery observations of PHAs, which are
fortuitous observations made before their discovery. We used the NAROO
machine to digitize the plates, and we performed the astrometric
reduction with the Gaia DR3 reference star catalog. We added the
results to the observation dataset of PHAs in order to determine new
orbital solutions and possibly detect the Yarkovsky effect with the
Numerical Integration of the Motion of an Asteroid (NIMA) program. In
addition, we considered a possible timing error in the orbit
adjustment, which is generally not taken into account in such
problems, and show its influence.
We were able to find precovery observations of PHAs in photographic
plate databases. Their introduction in the dataset show a significant
improvement of the accuracy of the new orbital solutions. They also
help in detecting and measuring the Yarkovsky effect and improve its
accuracy. Hence, we demonstrate the interest of the reduction or new
reduction of old photographic plates for the orbit determination of
PHAs.
Description:
We present measured positions of a selection of PHAs on photographic
plates from Caussols (010), Palomar (261) and La Silla (809)
observatories.
We present measured positions of (152563) 1992 BF on photographic
plates from Palomar Observatory (261).
We present measured positions of (4179) Toutatis on photographic
plates from Caussols (010) and Palomar (261) observatories.
We measured the beginning and the ending positions of the asteroid on
each photographic plate observation. The columns of the table
correspond to the UT date and time; the observed right ascension and
declination (ICRF) in hour, minute, second and degree, arcminute,
arcsecond, respectively; the IAU observatory code; the covariance
matrix error on both spherical coordinates in arcseconds; the
correlation coefficient; and the measurement error on both coordinates
in arcseconds. We digitized photographic plates with the high
precision digitizer of the NAROO Program. The astrometric reduction
was performed with the Gaia DR3 reference star catalog.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
phas.dat 101 23 PHAs positions (table 2)
toutatis.dat 81 16 (4179) Toutatis positions (table 3)
1992bf.dat 79 4 (152563) 1992BF positions (table 4)
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See also:
B/astorb : Orbits of Minor Planets (Bowell+, 2014-)
Byte-by-byte Description of file: phas.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Object number and/or name and/or designation
20- 23 I4 yr Obs.Y Year of the observation (UT)
25- 26 I2 "month" Obs.M Month of the observation (UT)
28- 29 I2 d Obs.D Day of the observation (UT)
31- 32 I2 h Obs.h Hour of the observation (UT)
34- 35 I2 min Obs.m Minute of the observation (UT)
37- 38 I2 s Obs.s Seconde of the observation (UT)
40- 41 I2 h RAh Right ascension (ICRF) J2000
43- 44 I2 min RAm Right ascension (ICRF) J2000
46- 51 F6.3 s RAs Right ascension (ICRF) J2000
53 A1 --- DE- Declination sign (ICRF) J2000
54- 55 I2 deg DEd Declination (ICRF) J2000
57- 58 I2 arcmin DEm Declination (ICRF) J2000
60- 64 F5.2 arcsec DEs Declination (ICRF) J2000
66- 68 I3 --- Obs IAU observatory code
70- 74 F5.3 arcsec RACe Right ascension covariance matrix error
({DELTA}α.cosδ) (G1)
76- 81 F6.3 arcsec DECe Declination covariance matrix error
({DELTA}δ) (G1)
83- 89 F7.5 --- Ccoef Correlation coefficient (G1)
91- 95 F5.3 arcsec e_RAs Right ascension measurement error
({DELTA}α.cosδ) (G1)
97-101 F5.3 arcsec e_DEs Declination measurement error
({DELTA}δ) (G1)
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Byte-by-byte Description of file: toutatis.dat 1992bf.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Obs.Y Year of the observation (UT)
6- 7 I2 "month" Obs.M Month of the observation (UT)
9- 10 I2 d Obs.D Day of the observation (UT)
12- 13 I2 h Obs.h Hour of the observation (UT)
15- 16 I2 min Obs.m Minute of the observation (UT)
18- 19 I2 s Obs.s Seconde of the observation (UT)
21- 22 I2 h RAh Right ascension (ICRF) J2000
24- 25 I2 min RAm Right ascension (ICRF) J2000
27- 32 F6.3 s RAs Right ascension (ICRF) J2000
34 A1 --- DE- Declination sign (ICRF) J2000
35- 36 I2 deg DEd Declination (ICRF) J2000
38- 39 I2 arcmin DEm Declination (ICRF) J2000
41- 45 F5.2 arcsec DEs Declination (ICRF) J2000
47- 49 I3 --- Obs IAU observatory code
51- 55 F5.3 arcsec RACe Right ascension covariance matrix error
({DELTA}α.cosδ) (G1)
57- 61 F5.3 arcsec DECe Declination covariance matrix error
({DELTA}δ) (G1)
63- 69 F7.5 --- Ccoef Correlation coefficient (G1)
71- 75 F5.3 arcsec e_RAs Right ascension measurement error
({DELTA}α.cosδ) (G1)
77- 81 F5.3 arcsec e_DEs Declination measurement error
({DELTA}δ) (G1)
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Global notes:
Note (G1): See section 2.3 of the paper.
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History:
From Anne-Charlotte Perlbarg
Acknowledgements:
These positions outcome from the NAROO program which was
supported by the DIM-ACAV of Ile-de-France region, PSL Research
University, the Programme National GRAM (PNGRAM), the Programme
National de Planetologie (PNP) and the Programme National
Soleil-Terre (PNST) of CNRS/INSU with INP and IN2P3, co-funded by
CNES, and the Gaia Specific Action (AF Gaia) of Paris Observatory.
(End) A.-C. Perlbarg [IPSA, Obs. de Paris - IMCCE], PVannier [CDS] 23-Oct-2023