J/other/SoSyR/53.368 Observations of the Galilean moons (Narizhnaya+, 2019)
Observations of the Galilean Moons of Jupiter at Pulkovo in 2018.
Narizhnaya N.V., Khovrichev M.Yu., Bikulova D.A.
<Solar System Res., 53, 368 (2019)>
=2019SoSyR..53..368N 2019SoSyR..53..368N (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Planets ; Positional data
Keywords: Galilean moons of Jupiter - precise positions - planetary theories -
satellite motion theories - CCD observations
Abstract:
Results of observations of the Galilean moons of Jupiter were carried
out at the Normal Astrograph of the Pulkovo Observatory in 2018. We
obtained 452 positions of the Galilean moons of Jupiter in the Gaia
DR1 catalog system (ICRF, J2000.0) and 671 differential coordinates of
the satellites relative to each other. The obtained mean errors in the
satellites normal positions on the right ascension and declination,
which demonstrate the intrinsic convergence of the observational
results, are (eps)RA=0.003" and (eps)DE= 0.003", respectively, for the
entire observational period. The errors of one difference are
(sigm)RA=0.070", and (sigm)DE=0.067",respectively. The equatorial
coordinates of the moons were compared to eight motion theories of
planets and satellites. On average, the (O.C) residuals in the both
coordinates relative to the motion theories are 0.014". The best
agreement with observations is achieved by combination of all four
motion theories of satellites with the planetary theory EPM2017, which
yields average (O-C) residuals of approximately 0.01" for each of
them. The new results were compared to those of the 2016-2017
observational season. As in the past, peculiarities in the behavior of
the (O-C) residuals for Io and Ganymede have been noticed.
Description:
Our observations were carried out with the Normal Astrograph
(D/F=330mm/ 3467mm) at Pulkovo (code is 084). The CCD camera (SBIG
ST-L-11K 3 CCD Camera with the 35'x25' field of view and the
0.530"/pixel scale) was used as a radiation detector. In total, for
the observational season, we obtained and processed 2590 CCD frames
containing the images of the Galilean moons. The observations were
made with exposures of 10s, which allowed direct measurements of the
equatorial coordinates of these objects in each of the frames. The
number of the Gaia DR1 reference stars (Arenou et al.,
2017A&A...599A..50A 2017A&A...599A..50A) within a frame ranged from 17 to 46. The duration
of observations within one night reached several hours; consequently,
to calculate the normal places of objects, the positions obtained for
the objects were divided into groups by time intervals of 10 min.
To make the measurements of a large body of frames automatic, we
developed the JSA software package that allows the WCS parameters (a
set of constants to convert unambiguously from the pixel coordinates
to the equatorial ones and back) to be determined and introduced into
a metadata block for each of the frames. This method of image analysis
was considered in a series of papers by A. Refregier and his coauthors
(Refregier, 2003MNRAS.338...35R 2003MNRAS.338...35R; Refregier and Bacon,
2003MNRAS.338...48R 2003MNRAS.338...48R; Massey and Refregier, 2005MNRAS.363..197M 2005MNRAS.363..197M).
Astrometric reduction algorithm is based on Turner's method with using
Gaia DR1 catalog as reference one. Ephemerides for comparison are
given by web- server "Natural Satellites Ephemeride Server MULTI-SAT"
developed by N.V. Emelyanov
(http://lnfm1.sai.msu.ru/neb/nss/nssephmr.htm). Two catalogue are
presented: 452 normal positions of Galilean satellites, 671
differential mutual coordinates of Galilean satellites.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
satsdat.dat 72 452 Positions of Galilean satellites
(1-Io, 2- Europa, 3-Ganymede, 4-Callisto)
satsatd.dat 63 671 Differential mutual coordinates of
Galilean satellites
--------------------------------------------------------------------------------
See also:
J/other/SoSyR/45.523 : Saturnian satellites CCD observations (Grosheva+, 2011)
J/other/SoSyR/49.383 : Galilean satellites + Jupiter positions
(Narizhnaya, 2015)
J/other/SoSyR/50.344 : Galilean moons + Jupiter positions (Narizhnaya, 2016)
J/other/SoSyR/52.312 : Galilean moons positions (Narizhnaya+, 2018)
Byte-by-byte Description of file: satsdat.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- SatNo [1/4] Identification number of galilean
satellite (1)
3- 18 A16 "date" Obs.Date Mean observation date (YYYY/MM/DD.ddddd)
20- 21 I2 h RAh Right ascension (J2000.0) (2)
23- 24 I2 min RAm Right ascension (J2000.0) (2)
26- 31 F6.3 s RAs Right ascension (J2000.0) (2)
33 A1 --- DE- Declination sign (J2000.0) (2)
34- 35 I2 deg DEd Declination (J2000.0) (2)
37- 38 I2 arcmin DEm Declination (J2000.0) (2)
40- 44 F5.2 arcsec DEs Declination (J2000.0) (2)
46- 52 F7.4 arcsec (O-C)RA (O-C) residual in right ascension (3)
54- 60 F7.4 arcsec (O-C)DE (O-C) residual in declination (3)
62- 66 F5.3 arcsec e_(O-C)RA Error of mean O-C in right ascension
68- 72 F5.3 arcsec e_(O-C)DE Error of mean O-C in declination
--------------------------------------------------------------------------------
Note (1): Satellite number as follows:
1 = Io
2 = Europa
3 = Ganymede
4 = Callisto
Note (2): topocentric equatorial coordinates of Galilean satellites, J2000.0.
Note (3): "Observed-Calculated" residuals by web-sever "MULTI-SAT", calculated
from ephemerides within the EPM2017 and V.Lainey-V.2.0|V1.1 theories
--------------------------------------------------------------------------------
Byte-by-byte Description of file: satsatd.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Sats [12/34] Idenficiation numbers of galilean
satellites (1)
4- 19 A16 "date" Obs.Date Mean observation date (YYYY/MM/DD.ddddd)
21- 28 F8.3 arcsec dRAs Differential Right ascension (J2000.0) (2)
30- 37 F8.3 arcsec dDEs Differential Declination (J2000.0) (2)
39- 44 F6.3 arcsec (O-C)RA (O-C) residual in right ascension (3)
46- 51 F6.3 arcsec (O-C)DE (O-C) residual in declination (3)
53- 57 F5.3 arcsec e_(O-C)RA Error of mean O-C in right ascension
59- 63 F5.3 arcsec e_(O-C)DE Error of mean O-C in declination
--------------------------------------------------------------------------------
Note (1): Identification numbers of satellites which observations were used for
deriving differential mutual satellites coordinates relative to each other.
Note (2): Differential coordinates of Galilean satellites (J2000.0) relative
each other.
Note (3): "Observed-Calculated" residuals by web-sever "MULTI-SAT", calculated
from ephemerides within the EPM2017 and V.Lainey-V.2.0|V1.1 theories.
--------------------------------------------------------------------------------
Acknowledgements:
Natalia Narizhnaya, Narizhnaya.nat(at)yandex.ru
References:
Arenou F., Luri X., Babusiaux C., Fabricius C., Helmi A., Robin A.C.,
Vallenari A., Blanco- Cuaresma S., Cantataudin T., Findeisen K., Reyle C.,
Ruiz-Dern L., Sordo R., Turon C., Walton, N.A. et al., Gaia Data
Release 1: Catalogue validation, Astron. Astrophys., 2017, vol. 599,
no. 50, pp. 1-50, 2017A&A...599A..50A 2017A&A...599A..50A
Refregier A., Shapelets-I. A method for image analysis, Mon. Not. R. Astron.
Soc., 2003, vol. 338, no. 1, pp. 35-47, 2003MNRAS.338...35R 2003MNRAS.338...35R
Refregier A. and Bacon D., Shapelets-II. A method for weak lensing
measurements, Mon. Not. R. Astron. Soc., 2003, vol. 338, no. 1, pp. 48-56,
2003MNRAS.338...48R 2003MNRAS.338...48R
Massey R. and Refregier A., Polar shapelets, Mon. Not. R. Astron. Soc.,
2005, vol. 363, no. 1, pp. 197-210, 2005MNRAS.363..197M 2005MNRAS.363..197M
Morgado B.,Vieira-Martins R., Assafin M., Machado D.I., Camargo J.I.B.,
Sfair R., Malacarne M., Braga-Ribas F., Robert V., Bassallo T., Benedetti-
Rossi G., Boldrin L.A., Borderes-Motta G., Camargo B.C.B., Crispim A.,
Dias-Oliveira A., Gomes-Junior A.R., Lainey V., Miranda J.O., Moura T.S.,
Ribeiro F.K., Santana T., Santos-Filho S., Trabuco L.L., Winter O.C.,
Yamashita T.A.R. APPROX - mutual approximations between the Galilean
moons: the 2016-2018 observational campaign // Mon. Not. Roy. Astron. Soc.,
2019. V. 482. Issue 4. p. 5190-5200, 2019MNRAS.482.5190M 2019MNRAS.482.5190M
Narizhnaya N.V., Khovrichev M.Yu., Apetyan A.A., Bikulova D.A., Ershova A.P.,
Balyaev I.A., Kulikova A.M., O'Skina K.I., and Maksimova L.A.,
Astrometric observations of the Galilean Moons of Jupiter at the Pulkovo
normal astrograph in 2016.2017, Sol. Syst. Res., 2018, vol. 52, no. 4,
pp. 312-319, 2018SoSyR..52..312N 2018SoSyR..52..312N, Cat. J/other/SoSyR/52.312
(End) Natalia Narizhnaya [GAO, Russia], Patricia Vannier [CDS] 26-Nov-2019