J/other/PSS/260.06085 Major uranian sat. astrometric performance (Fang+, 2025)
Astrometric performance of the five major Uranian satellites using a
narrow-band Methane filter.
Fang X.Q., Peng Q.Y., Lu X., Guo B.F.
<Planetary and Space Science, 260, 106085 (2025)>
=2025P&SS..26006085F 2025P&SS..26006085F (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Planets ; Positional data
Abstract:
During ground-based observations of satellites near a bright planet,
the satellite images are often affected by the planet's halo,
introducing significant uncertainty in their astrometric positions. To
address this issue, we employed a narrow-band methane filter for
observations of the five major Uranian satellites, which makes them
easily discernible on CCD frames without requiring halo removal
procedures. We systematically evaluated the astrometric performance of
this Methane filter and compared it to that of the commonly used Clear
and Cousins-I filters. Totally, the positional precision for most of
the four brightest satellites is approximately 30mas in both right
ascension and declination, comparable to the Cousins-I filter and
superior to the Clear filter. On the other hand, the faint satellite
Miranda achieves a precision of better than 80mas after image
stacking in the methane band images. Based on our experiments, we
recommend using the Methane filter for observing objects with an
apparent visual magnitude brighter than 15, as it offers a sufficient
signal-to-noise ratio (SNR) of approximately 55 within a reasonable
exposure time of 200s using a 0.8m telescope.
Description:
We observed the five major Uranian satellites using two different
telescopes: a 0.8m azimuthal-mounted telescope at Yaoan Station,
Purple Mountain Observatory (IAU code O49, E101:10:51, N25:31:42,
H1943m), and a 1m equatorial-mounted telescope at Kunming Station,
Yunnan Observatory (IAU code 286, E102:47:18, N25:01:46, H1952m). The
0.8m telescope is equipped with a narrow-band methane filter centered
at 889nm and having a width of 15nm.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table.dat 57 860 Uranian satellites astrometry
--------------------------------------------------------------------------------
See also:
J/A+AS/107/559 : Position of Uranian satellites (Veiga+, 1994)
J/A+AS/113/557 : Uranian satellites (Veiga+, 1995)
J/A+AS/138/247 : Uranian satellites 1995-1998 (Veiga+, 1999)
J/A+A/391/775 : Uranian satellites in 1995/97 (Shen+, 2002)
J/A+A/454/683 : Position of Uranian satellites (Veiga+, 2006)
J/other/PSS/134.96 : 2007-2016 Pulkovo Uranian satellites obs. (Ershova+, 2017)
J/other/PSS/210.1 : Astrometry of the 5 largest Uranian sat. (Camargo+, 2022)
J/AJ/164/37 : 2008-2014 precise position of 5 Uranian satellites
(Zhang+, 2022)
J/ApJS/273/25 : Positions of 5 Uranian satellites from Yunnan obs.
(Zhang+, 2024)
Byte-by-byte Description of file: table.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Sat [U1 U2 U3 U4 U5] Uranian satellite
5- 20 F16.8 d JD Exposure middle time of each CCD frame in
Julian Date (UTC)
23- 24 I2 h RAh Observed topocentric astrometric position
in right ascension (J2000)
26- 27 I2 min RAm Observed topocentric astrometric position
in right ascension (J2000)
29- 35 F7.4 s RAs Observed topocentric astrometric position
in right ascension (J2000)
37 A1 --- DE- Observed topocentric astrometric position
in declination sign (J2000)
38- 39 I2 deg DEd Observed topocentric astrometric position
in declination (J2000)
41- 42 I2 arcmin DEm Observed topocentric astrometric position
in declination (J2000)
44- 49 F6.3 arcsec DEs Observed topocentric astrometric position
in declination (J2000)
52- 54 A3 --- ObsCode IAU code of the observatory
57 A1 --- Filt [MCI] Filter used (1)
--------------------------------------------------------------------------------
Note (1): Filters as follows:
M = Methane
C = Clear
I = Cousins-I
--------------------------------------------------------------------------------
Acknowledgements:
X.Q. Fang, xqfang(at)stu2020.jnu.edu.cn
(End) Patricia Vannier [CDS] 27-Feb-2025