Results 41 to 50 of about 4,915 (213)
24. Photographic Astrometry (Astrometrie Photographioue) [PDF]
Transactions of the International Astronomical Union, 1991 Despite some much publicized disappointments, the highlights of Astrometry during the past three year period are dominated by the successful launches of the ES A Hipparcos astrometric satellite and the NASA Hubble Space Telescope. For the past 15 to 20 years the research activities of many Commission members have been monopolized by the design and ...
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Globally Critical Infrastructure: The Unique Risks and Challenges
Risk Analysis, Volume 45, Issue 12, Page 4804-4817, December 2025.ABSTRACT Critical infrastructure is typically identified at the national level. However, disruption to certain infrastructure systems, facilities, and assets can have negative consequences for global societies. Such globally critical infrastructure entails a distinct risk profile for both countries dependent on the infrastructure, and countries that ...
Zachary Kallenborn, Henry H. Willis
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Odessa Astronomical Publications, 2017 This catalogue contains the results of 1321 right ascensions observations of 2dj Radio References Stars obtained al Odessa with the Repsold transit circle in 1990-1993.
A. P. Chelombit'ko
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Astronomische Nachrichten, Volume 346, Issue 9, November 2025.ABSTRACT We present James Webb Space Telescope observations of M 4—the closest globular cluster—that probe the lower Main Sequence down to the hydrogen‐burning limit. The unveiled stellar sequence reaches much fainter luminosities than previously possible, revealing a few extremely red objects that are consistent with brown dwarfs as cool as Teff∼1000K$
L. R. Bedin +10 more
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The Astronomical JournalR. A. Jacobson determined the orbits of the Uranian satellites, the masses of Uranus and its satellites, and the orientation of the pole of Uranus from Earth-based astrometry, Earth-based ring occultations, and observations acquired with the Voyager 2 ...
Robert A. Jacobson, Ryan S. Park
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Mining of the Milky Way Star Archive Gaia-DR2. Searching for Binary Stars in Planetary Nebulae
Proceedings, 2020 The aim of this work is to search for binary stars associated to planetary nebulae (ionized stellar envelopes in expansion), by mining the astronomical archive of Gaia DR2, that is composed by around 1.7 billion stellar sources.
Iker González-Santamaría +4 more
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Earth and Space Science, Volume 12, Issue 10, October 2025.Abstract High‐precision Earth Rotation Parameter (ERP) products often experience delays that range from several days to weeks. The use of precise forecasting models can effectively compensate for the impact of such delays. Based on a systematic analysis of the forecasting capabilities of the traditional harmonic least squares fitting and autoregressive
Chen Ren +4 more
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Astrometric star catalogues as combination of Hipparcos/Tycho catalogues with ground-based observations [PDF]
Serbian Astronomical Journal, 2004 The successful ESA mission Hipparcos provided very precise parallaxes positions and proper motions of many stars in optical wavelength. Therefore it is a primary representation of International Celestial Reference System in this wavelength.
Vondrák J.
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Speckle Interferometry at the OAN-SPM México: Multiband Astrometry of Double Stars Measured in 2018 and 2019 [PDF]
, 2021 C. A. Guerrero +11 more
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Macho Photometry and Astrometry [PDF]
Symposium - International Astronomical Union, 1995 MACHOs (Massive Astrophysical Compact Halo Objects) have been discovered by their relativistic amplification of light from distant stars as they crossed very near to the line-of-sight. The very few events were detected from more than a billion photometric measurements of millions of stars in the LMC.
Høg, E. +2 more
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