Results 61 to 70 of about 3,440 (204)

Consolidation of the Gaia catalogue with Chinese Space Station Telescope astrometry

Frontiers in Astronomy and Space Sciences, 2022
The issue of preservation and improvement of the Gaia catalogue throughout the next few decades is addressed. The goal of this study is to evaluate the feasibility of astrometric parameter update, for objects already in the catalogue, by inclusion of new
M. Gai, A. Vecchiato, D. Busonero, A. Riva, R. Cancelliere, M. Lattanzi, Z. Qi   +6 more
doaj   +1 more source

Tycho Astrometry and Photometry [PDF]

Symposium - International Astronomical Union, 1986
The HIPPARCOS Star Mappers were designed to determine the satellite attitude by observation of stars with known positions. ESA has now enhanced them so that the continuous photon counts from two photo multipliers with B and V response will be recorded.
openaire   +4 more sources

Isolated Neutron Stars as Science Validation for XMM2ATHENA: Ensuring Robust Data for Future X‐Ray Astronomy

Astronomische Nachrichten, Volume 346, Issue 3-4, March-May 2025.
ABSTRACT The discovery of radio‐quiet, x‐ray thermally emitting isolated neutron stars (XINSs) in the ROSAT All‐Sky Survey revealed a previously overlooked component of the neutron star population. Advancements in x‐ray instrumentation and the availability of deep, wide‐area optical surveys now enable us to explore XINSs at fainter x‐ray fluxes and ...
Adriana Mancini Pires, Christian Motch, Axel Schwope, Iris Traulsen, Jean Ballet, Sudip Chakraborty, David Homan, Jan Kurpas, Ada Nebot Gomez‐Moràn, François‐Xavier Pineau, Hugo Tranin, Natalie Webb   +11 more
wiley   +1 more source

An Updated View of the Milky Way from Maser Astrometry

Universe, 2022
Astrometric observations of maser sources in the Milky Way, using the Very Long Baseline Interferometry (VLBI) technique, have been exploited to determine the spiral structure of our Galaxy. Several major spiral arms have now been pinpointed in the first
Katharina Immer, Kazi L. J. Rygl
doaj   +1 more source

Uncertainties in Ground‐Based Visual Double Star Measures

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT Stellar masses are found from the orbital elements of binary systems which are, in turn, computed from weighted astrometric measures. Astrometric measures of double stars (their position angle and separation) rarely include uncertainties, and published binary star orbits rarely include the weighting systems used in the determination of the ...
Roderick R. Letchford, Graeme L. White
wiley   +1 more source

The Effect of Age on the Grouping of Open Clusters: II—Are There Old Binary Clusters?

Universe, 2022
In the present study, we continue testing the Primordial Group hypothesis (Casado 2022), which postulates that only sufficiently young open clusters can be binary or multiple, and old clusters are essentially single.
Juan Casado
doaj   +1 more source

JWST Imaging of the Closest Globular Clusters—V. The White Dwarfs Cooling Sequence of M4

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT We combine infrared (IR) observations collected by the James Webb Space Telescope with optical deep images by the Hubble Space Telescope taken ~20 years earlier to compute proper‐motion membership for the globular cluster (GC) M4 (NGC 6121) along its entire white dwarf (WD) cooling sequence (CS).
Luigi R. Bedin, Mattia Libralato, Maurizio Salaris, Domenico Nardiello, Michele Scalco, Massimo Griggio, Jay Anderson, Pierre Bergeron, Andrea Bellini, Roman Gerasimov, Adam J. Burgasser, Daniel Apai   +11 more
wiley   +1 more source

Integrity Assessment and Verification Procedure of Angle-only Data for Low Earth Orbit Space Objects with Optical Wide-field PatroLNetwork (OWL-Net)

Journal of Astronomy and Space Sciences, 2019
The Optical Wide-field patroL-Network (OWL-Net) is a global optical network for Space Situational Awareness in Korea. The primary operational goal of the OWL-Net is to track Low Earth Orbit (LEO) satellites operated by Korea and to monitor the ...
Jin Choi, Jung Hyun Jo, Sooyoung Kim
doaj   +1 more source

Pulsar Astrometry [PDF]

Symposium - International Astronomical Union, 1984
High precision measurements of the celestial coordinates of pulsars are desirable for a number of reasons. If carried out at several epochs, the measurements can yield angular proper motions; together with distance estimates based on dispersion measure, the proper motion of a pulsar reveals two of three components of its space velocity, and ...
Joseph H. Taylor, Carl R. Gwinn, Joel M. Weisberg, Lloyd A. Rawley   +3 more
openaire   +1 more source

Revisiting Variable Stars Near Globular Clusters South of −29° Declination

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT We review an often‐cited but seldom‐accessed catalogue by Fourcade and Laborde (1966) of 785 variable stars near 47 southern Galactic globular clusters, and recover the locations of 85 stars that were not incorporated into subsequent variable star catalogues and hence have become “lost” to the literature.
Andrew C. Layden, Julia Evangelista, Sakshi Gupta, Mithilesh Mittameda, Eva Mulloy, Sohan I. Muslim, Tiyinoluwa Olushola‐Alao, Akul Rishi   +7 more
wiley   +1 more source