- Observatory and telescope: Sylvester Robotic Observatory (SRO): 33cm f/4.5 Newtonian on Paramount GT-1100s mount - Detector: SRO: SBIG ST7e, 1.24 pixels, 15.8x10.5 FOV, cooled -10<T<-30{deg}C - Method of data reduction: Aperture photometry using MIRA, by Axiom Research - Method of minimum determination: Digital tracing paper method, bisection of chords, curve fitting, and (occasionally) Kwee and van Woerden (1956BAN....12..327K)
Astrometric positions of the first eight largest Saturnian satellites and the Lagrangian satellites Helene, Telesto and Calypso are presented from 493 CCD frames taken at the oppositions in 1995 through 1999. The images were obtained over 27 nights. Observed positions are compared with the calculated ones from Vienne and Duriez (1995A&A...297..588V) TASS 1.7 for the large satellites and from JPL positions for the Lagrangian satellites. The rms is about 0.12" for the former but 0.20" for Iapetus and 0.28" for Hyperion. For the Lagrangian satellites it is about 0.21" for Helene, 2.02" for Telesto and 0.60" for Calypso.
TY Pup is a well-known bright eclipsing binary with an orbital period of 0.8192 days. New light curves in B, V, (RI)_C_ bands were obtained with the 0.61 m reflector robotic telescope (PROMPT-8) at CTIO in Chile during 2015 and 2017. By analyzing those photometric data with the W-D method, it is found that TY Pup is a low-mass-ratio (q~0.184) and deep-contact binary with a high fill-out factor (84.3%). An investigation of all available times of minimum light including three new ones obtained with the 60 cm and the 1.0 m telescopes at Yunnan Observatories in China indicates that the period change of TY Pup is complex. An upward parabolic variation in the O-C diagram is detected to be superimposed on a cyclic oscillation. The upward parabolic change reveals a long-term continuous increase in the orbital period at a rate of dP/dt=5.57(+/-0.08)x10^-8^ days/yr. The period increase can be explained by mass transfer from the less massive component (M_2_~0.3 M_{sun}_) to the more massive one (M_1_~1.65 M_{sun}_). The binary will be merging when it meets the criterion that the orbital angular momentum is less than three times the total spin angular momentum, i.e., J_orb_<3J_rot_. This suggests that the system will finally merge into a rapid-rotating single star and may produce a luminous red nova. The cyclic oscillation in the O-C diagram can be interpreted by the light-travel time effect via the presence of a third body.
The file innerjov.dat contains 236 intersatellite positions of the inner Jovian moons Thebe, Amalthea, Adrastea and Metis derived from the observations made with the 2-m Zeiss RCC telescope of Terskol Observatory (Terskol peak, Northern Caucasus, long=42.50083{deg}, lat=43.27427{deg}, h=3100m) in October-November 1999 and in November 2000. The Two-Channel Focal Reducer of the Max-Planck Institute for Aeronomy (MPAe,Germany) was used for acquisition of the images. We provide {delta}({alpha}) and {delta}({delta}) of Thebe and Amalthea with respect to the Galilean satellites, while the positions of Adrastea and Metis are referred to either the Galilean moons or to Thebe or Amalthea. Astrometric topocentric coordinates J2000.0 of the Galilean satellites were used for scale and orientation angle determination. The array scale was corrected for differential refraction and differential aberration to first-order.
This paper give positions of Martian satellites system from CCD observations obtained at the Cassegrain focus of a 1.6m reflector for the years 1995 and 2003.
229 CCD positions of Nereid taken between 1993 and 1998 are presented. Many of the observations were taken near the periapsis. Considering also the other published positions we have a good distribution of the observations on the eccentric orbit of the satellite. Using a numeric integration method we fitted all these observations in order to determine one state vector for the orbit. The observed minus calculated standard deviation for all observations is 0.23", and for our observations it is 0.16".
In 1998 and 1999, we started observations of the 9th satellite of Saturn. We made 163 observations using the 120cm-telescope of Observatoire de Haute-Provence, France. We used the USNO A2 catalogue (Cat. <I/252>) of stars for the astrometric reduction. With the help of observations of optical counterparts of ICRF sources, a zonal correction to the USNO A2.0 catalogue was computed and applied to the Phoebe positions. A comparison to the most recent theories was made.
The astrometric positions of seven saturnian satellites are presented. Positions were derived from more then 5000 CCD frames taken with 26-inch Zeiss refractor at Pulkovo from Jan 2008 to may 2009. Astrometric reduction algorithm is based on Turner's method with using UCAC2 catalog as reference one. Observed positions were compared with theoretical ones from TASS 1.7 (Viennel & Duriez, 1995A&A...297..588V). The accuracy is about 0.05 arcsec. Also positions of Saturn were obtained from observations of satellites 2-6.
Astrometric positions of the Neptunian Satellite Triton are given for the opposition of Neptune for the years 1989 to 1994. These positions where measured on 433 CCD frames obtained at the Cassegrain focus of a 1.6 m reflector. They are compared with theoretical positions calculated from Jacobson et al. (1991A&A...247..565J). The observed minus calculated residuals referred to Neptune have standard deviations of the order of 0.11".
We present 18365 astrometric observations of 290 visual binaries obtained with the 26-inch refractor of Pulkovo Observatory during 2014-2019. The separation between components is from 1.3" to 37" with a median value of 4.8". For a single observation, the mean separation error is 0.013", and the mean position angle error is 0.44{deg}/rho, where rho is an angular distance in arcseconds. We compare the observations of sample stars with the data from the Gaia DR2 catalog and the results of the ground-based observations performed with other telescopes.
