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- ID:
- ivo://org.gavo.dc/apfs/res/apfs_new/gdr2query
- Title:
- APFS Gaia DR2 Simple Query
- Short Name:
- apfs_gaiaquery
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This service is an extension of the Apparent Places of Fundamental Stars (APFS) computing exact geocentric positions in both the CIO and equinox systems to stars from the Gaia DR2 result catalogue.
- ID:
- ivo://org.gavo.dc/apfs/res/apfs_new/hipquery
- Title:
- APFS HIP Simple Query
- Short Name:
- apfs_hipquery
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This service is an extension of the Apparent Places of Fundamental Stars (APFS) computing exact geocentric positions in both the CIO and equinox systems to stars from the Hipparcos catalogue.
- ID:
- ivo://org.gavo.dc/apfs/res/apfs_new/catquery
- Title:
- APFS Simple Query Form
- Short Name:
- apfs_catquery
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- The Apparent Places of Fundamental Stars (APFS) give exact geocentric positions for a selected set of FK6 stars.
- ID:
- ivo://CDS.VizieR/J/A+A/383/1054
- Title:
- Astrometry of Pluto and Saturn in 1995-2001
- Short Name:
- J/A+A/383/1054
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we publish astrometric positions of Pluto and satellites of Saturn obtained with the Bordeaux and Valinhos CCD meridian circles. These observations are used to test the DE403 and DE405 ephemerides.
- ID:
- ivo://CDS.VizieR/J/other/PSS/210.1
- Title:
- Astrometry of the 5 largest Uranian sat.
- Short Name:
- J/other/PSS/210.
- Date:
- 14 Dec 2021 08:12:44
- Publisher:
- CDS
- Description:
- We present the astrometry of the five largest satellites of Uranus from observations spread over almost three decades with photographic plates and CCDs (mainly), taken at the Pico dos Dias Observatory - Brazil. All positions presented here are obtained from the reanalysis of measurements and images used in previous publications. Reference stars are those from the Gaia Early Data Release 3 (Gaia EDR3) allowing, in addition to a higher accuracy, a larger number of positions of the largest satellites as compared to our previous works. From 1982 to 1987, positions were obtained from photographic plates. From 1989 to 2011, CCDs were used. On average, we obtained {Delta}{alpha}cos{delta}=-11(+/-52) milli-arcseconds and {delta}{delta}=-14 (+/-43) milli-arcseconds for the differences in the sense observation minus ephemerides (DE435+ura111). Comparisons with different ephemerides (DE440, INPOP21a, INPOP19a and NOE-7-2013-MAIN) and results from stellar occultations indicate a possible offset in the (Solar System) barycentric position of the Uranian system barycenter. Overall, our results are useful to improve dynamical models of the Uranian largest satellites as well as the orbit of Uranus.
- ID:
- ivo://CDS.VizieR/VI/140
- Title:
- Catalogue of Lunar Eclipse Crater Timings
- Short Name:
- VI/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue contains lunar eclipse crater timing observations made during 94 lunar eclipses in the period 1842 and 2011, together with a reduction of each observation.
- ID:
- ivo://CDS.VizieR/J/A+A/355/398
- Title:
- Celestial Ephemeris Origin definition
- Short Name:
- J/A+A/355/398
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The adoption of the International Celestial Reference System ICRS, and of the corresponding Frame, ICRF, by the 23rd General Assembly of the International Astronomical Union, calls for a redefinition of the departure point on the true equator. Several possibilities have been suggested. This paper considers the use of the non-rotating origin (Guinot, 1979, In: McCarthy D.D., Pilkington J.D. (eds.) Time and the Earth's Rotation. D. Reidel Pub. Co, p. 7). The ``Celestial Ephemeris Origin'' (CEO) is defined here as the non-rotating origin on the equator of the Celestial Ephemeris Pole (CEP). Developments valid at the microarcsecond, based on the best model for precession, nutation and pole offset at J2000.0 with respect to the pole of ICRF, are provided for computing the CEP coordinates and the position of the CEO. It is shown that an operational definition of UT1 based on the CEO leads to values which are insensitive at the microarcsecond level to future improvements of this model.
- ID:
- ivo://CDS.VizieR/J/A+A/400/1145
- Title:
- Celestial Intermediate Pole & Ephemeris Origin
- Short Name:
- J/A+A/400/1145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Expressions for the position of the Celestial Intermediate Pole (CIP) and the Celestial Ephemeris Origin (CEO) in the Geocentric Celestial Reference System (GCRS) have been computed using the IAU 2000A precession-nutation. These expressions are for use in the new transformation between the GCRS and the International Terrestrial Reference System (ITRS) which is recommended by IAU Resolution B1.8. Various comparisons and numerical checks have been performed between the classical and the new transformations based on the IAU 2000A precession-nutation. These comparisons revealed necessary improvements to be applied to the classical form of the transformation in order to achieve the required level of accuracy. Once these improvements are applied, the consistency between the positions of the CIP in the GCRS corresponding to the classical and the new transformations is at a level of a few microarcseconds after one century. This work has demonstrated that the new method, in addition to providing an explicit separation between precession-nutation of the equator from Earth rotation, is more simple, compact and direct than the classical one, achieving accuracies at the level of a few microarcseconds with greatly reduced scope for accidental misuse. The resulting expressions for X, Y and s have been included in the IERS Conventions 2000.
- ID:
- ivo://CDS.VizieR/VI/88
- Title:
- Ephemerides of Pluto (PLUTO95)
- Short Name:
- VI/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Pluto's motion has been represented with series resulting of an approximation by frequency analysis (see Chapront 1995) of JPL numerical integration DE200. Series represent the heliocentric coordinates of Pluto as functions of time between 1700 and 2100. This catalog completes the VSOP87 theories developed at the Bureau des Longitudes (see Cat. <VI/81>)
