J/MNRAS/449/2638 Precise CCD positions of Phoebe in 2011-2014 (Peng+, 2015)
Precise CCD positions of Phoebe in 2011-2014.
Peng Q.Y., Wang N., Vienne A., Zhang Q.F., Li Z., Meng X.H.
<Mon. Not. R. Astron. Soc., 449, 2638-2642 (2015)>
=2015MNRAS.449.2638P 2015MNRAS.449.2638P (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Positional data
Keywords: methods: observational - techniques: image processing - astrometry -
planets and satellites: general
Abstract:
346 new CCD observations during the years 2011-2014 have been reduced
to derive the precise positions of Phoebe, the ninth satellite of Saturn.
The observations were made by the 2.4 m telescope at Yunnan Observatory
over nine nights. Due to the use of a focal-reducer on the telescope,
its significant geometric distortion is solved for and removed for each
CCD field of view. The positions of Phoebe are measured with respect to
the stars in UCAC2 catalogue (Cat. I/289). The theoretical position of
Phoebe was retrieved from the Institute de Mechanique Celeste et de Calcul
des Ephemerides (IMCCE) ephemeris which includes the latest theory PH12
by Desmars et al. (2013, J/A+A/553/A36), while the position of Saturn was
obtained from the Jet Propulsion Laboratory ephemeris DE431. Our results
show that the mean O-Cs (observed minus computed) are -0.02 and
-0.07 arcsec in right ascension and declination, respectively. The
dispersions of our observations are estimated at about 0.04 arcsec in
each direction.
Description:
Since 2011, we have been engaged in a systematic observation of the
Saturnine satellite, Phoebe. All the observations were made with the
2.4 m telescope at Yunnan Observatory. The site (i.e. IAU code O44) is
at longitude E100°01'51", latitude N26°42'32" and height 3193 m
above sea level. A total of 346 frames of CCD images have been obtained
for the satellite as well as 331 frames of CCD calibration images. The
exposure time for each CCD frame ranged from 20 to 60 s, depending on
the meteorological conditions.
Table 6 lists an extract of the observed topocentric apparent
positions of Phoebe. The complete data can be obtained in the data
base of Natural Satellites of the IMCCE
(http://nsdb.imcce.fr/nsdb/home.html).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table6.dat 42 346 CDD observations of Phoebe in 2011-2014
--------------------------------------------------------------------------------
See also:
J/A+A/391/767 : CCD observations of Phoebe in 1998-1999 (Fienga+, 2002)
J/A+A/454/379 : 2003-2004 Phoebe CCD astrometry (Qiao+, 2006)
J/A+A/553/A36 : Catalogue of Observations of Phoebe (Desmars+, 2013)
J/A+A/575/A73 : Astrometry of the Saturnian satellites 2004-12
(Tajeddine+, 2015)
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 F14.6 d JD Julian Date of exposure middle time (UTC)
16- 17 I2 h RAh Hour of Right Ascension (J2000) (1)
19- 20 I2 min RAm Minute of Right Ascension (J2000) (1)
22- 28 F7.4 s RAs Second of Right Ascension (J2000) (1)
30 A1 --- DE- Sign of the Declination (J2000) (1)
31- 32 I2 deg DEd Degree of Declination (J2000) (1)
34- 35 I2 arcmin DEm Arcminute of Declination (J2000) (1)
37- 42 F6.3 arcsec DEs Arcsecond of Declination (J2000) (1)
--------------------------------------------------------------------------------
Note (1): Observed topocentric apparent positions of Phoebe.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 22-Nov-2019