Astrometric observations of the Uranian satellites with the Faulkes Telescope North in 2007 September

Abstract

The results of astrometric observations of the main Uranian satellites taken with the Faulkes Telescope North are presented. A median filter algorithm was applied to subtract a scattered‐light halo caused by Uranus. The Two‐Micron All‐Sky Survey (2MASS) and USNO‐B1.0 were used as reference catalogues. The mean value of the differences between the equatorial coordinates of the satellites determined with 2MASS and USNO‐B1.0 is close to 200 mas. A comparison of the observed equatorial coordinates of the satellites and their relative positions with ephemerides based on different combinations of theories of motion of Uranus and its satellites (DE405+GUST86, DE405+GUST06, INPOP+GUST86, INPOP+GUST06) was performed. The satellites' positions obtained with respect to 2MASS are in better agreement with theories. The values of (O−C) of the equatorial coordinates determined with the 2MASS are mainly less than 100 mas. The majority of (O−C) of relative positions are within ±50 mas. The mean values of the standard errors of (O−C) are within 20 to 60 mas.

Astrometric observations of the main Uranian satellites at the Pulkovo Observatory in 2007–2016

“…The CCD-images of four main Uranian satellites (Ariel, Umbriel, Titania and Oberon) are available for robust position determination. Final astrometric accuracy of the satellites' observations is similar to the positional precision presented in several recent studies (Camargo et al, 2015;Khovritchev, 2009). The fifth main satellite of Uranus (Miranda) is usually located within a small angular distance from the planet (with a bright part of scattered-light halo caused by Uranus).…”

CCD astrometric observations of the five major Uranian satellites made in 1998–2007 and comparison with theory★

“…In recent years, the focus on the Uranian system was above all concentrated on mutual events by the scientific community so that the regular observation of the five major Uranian satellites was a little neglected. Consequently, the Natural Satellite Data Base (NSDB) of the Institut de Mécanique Céleste et de Calcul des Ephémérides shows that only a few data were observed in the most recent years by Veiga & Bourget (2006), Izmailov et al (2007) and Khovritchev (2009).…”