相关论文: Connecting terrestrial to celestial reference fram…
In this paper we outline several problems related to the realization of the international celestial and terrestrial reference frames ICRF and ITRF at the millimeter level of accuracy, with emphasis on ICRF issues. The main topics considered…
The current state of the link problem between radio and optical celestial reference frames is considered. The main objectives of the investigations in this direction during the next few years are the preparation of a comparison and the…
The International Celestial Reference Frame (ICRF, Ma et al. 1998) is currently the best realization of a quasi-inertial reference system. It is based on more than 10 years of cumulated geodetic and astrometric VLBI observations of compact…
The goal of this presentation is to report the latest progress in creation of the next generation of VLBI-based International Celestial Reference Frame, ICRF3. Two main directions of ICRF3 development are improvement of the S/X-band frame…
The highly-accurate optical reference frame GCRF (Gaia Celestial Reference Frame) is expected to be available in several years. By the same time, a new version of radio reference frame ICRF (International Celestial Reference Frame) will be…
A new realization of the International Celestial Reference Frame (ICRF) is presented based on the work achieved by a working group of the International Astronomical Union (IAU) mandated for this purpose. This new realization, referred to as…
Reference systems and frames are crucial for high precision absolute astrometric work, and their foundations must be well-defined. The current frame, the International Celestial Reference Frame, will be discussed: its history, the use of…
The Gaia optical reference frame is intrinsically undefined with respect to global orientation and spin, so it needs to be anchored in the radio-based International Celestial Reference Frame (ICRF) to provide a referenced and quasi-inertial…
Context: We introduce the computation of global reference frames from Very Long Baseline Interferometry (VLBI) observations at the Vienna International VLBI Service for Geodesy and Astrometry (IVS) Analysis Center (VIE) in detail. We focus…
The fundamental celestial reference frame (CRF) is based on two catalogs of astrometric positions, the third realization of the International Celestial Reference Frame (ICRF3), and the much larger Gaia~CRF, built from the third data release…
The International VLBI Service for Geodesy & Astrometry (IVS) regularly provides high-quality data to produce Earth Orientation Parameters (EOP), and for the maintenance and realization of the International Terrestrial and Celestial…
The current realization of the International Celestial Reference Frame (ICRF) comprises a total of 717 extragalactic radio sources distributed over the entire sky. An observing program has been developed to densify the ICRF in the northern…
A possible method for linking the optical Gaia Celestial Reference Frame (GCRF) to the VLBI-based International Celestial Reference Frame (ICRF) is to use radio stars in a manner similar to that in the linking of the Hipparcos Celestial…
The third realization of the International Celestial Reference Frame (ICRF3) was adopted in August 2018 and includes positions of extragalactic objects at three frequencies: 8.4 GHz, 24 GHz, and 32 GHz. In this paper, we present celestial…
Optical positions from the SuperCOSMOS Sky Survey have been compared in detail with accurate radio positions that define the second realisation of the International Celestial Reference Frame (ICRF2). The comparison was limited to the IIIaJ…
This work introduces a novel three-fold classification of reference frames in General Relativity, distinguishing between Idealised Reference Frames (IRFs), Dynamical Reference Frames (DRFs), and Real Reference Frames (RRFs). By defining a…
Context. We present a celestial reference frame (CRF) based on the combination of independent, multifrequency radio source position catalogs using nearly 40 years of Very Long Baseline Interferometry observations at the standard geodetic…
Nowadays, tens of satellites carry hyperspectral spectrometers. Such instruments allow decomposing the light that exits the atmosphere from its top into hundreds to thousands of contiguous spectral channels. By analysis of the light…
The ICRF, currently based on the position of 717 extragalactic radio sources observed by VLBI, is the fundamental celestial reference frame adopted by the IAU in 1997. Within the next 10 years, the European space astrometry mission Gaia, to…
Using very long baseline interferometry data for the sources that comprise the third International Celestial Reference Frame (ICRF3), we examine the quality of the formal source position uncertainties of ICRF3 by determining the excess…