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Related papers: Empirical Uncertainty Estimators for Astrometry fr…

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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…

Instrumentation and Methods for Astrophysics · Physics 2024-08-05 Phil Cigan , Valeri Makarov , Nathan Secrest , David Gordon , Megan Johnson , Sebastien Lambert

Optimal error estimation is key to achieve accurate photometry and astrometry. Stellar fluxes and positions in high angular resolution images are typically measured with PSF fitting routines, such as StarFinder. However, the formal…

Instrumentation and Methods for Astrophysics · Physics 2022-08-12 E. Gallego-Cano , R. Schödel , A. T. Gallego-Calvente , A. M. Ghez

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…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Adam Schaefer , Richard Hunstead , Helen Johnston

The knowledge of the orbit or the ephemeris uncertainty of asteroid presents a particular interest for various purposes. These quantities are for instance useful for recovering asteroids, for identifying lost asteroids or for planning…

Earth and Planetary Astrophysics · Physics 2015-06-15 Josselin Desmars , David Bancelin , Daniel Hestroffer , William Thuillot

This paper investigates methods for estimating uncertainty in semantic segmentation predictions derived from satellite imagery. Estimating uncertainty for segmentation presents unique challenges compared to standard image classification,…

Computer Vision and Pattern Recognition · Computer Science 2025-10-23 Melanie Rey , Andriy Mnih , Maxim Neumann , Matt Overlan , Drew Purves

Between 1997 and 2004 several observing runs were conducted mainly with the CTIO 0.9 m to image ICRF counterparts (mostly QSOs) in order to determine accurate optical positions. Contemporary to these deep CCD images the same fields were…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Norbert Zacharias , Marion I. Zacharias

I discuss an issue arising in analyzing data from astronomical surveys: accounting for measurement uncertainties in the properties of individual sources detected in a survey when making inferences about the entire population of sources.…

Astrophysics · Physics 2009-11-10 Thomas J. Loredo

Precision geodesy relies on the stability of the International Celestial Reference Frame (ICRF), yet its reference sources, Active Galactic Nuclei (AGN), exhibit changes in source structure that can manifest as apparent shifts in their…

High Energy Astrophysical Phenomena · Physics 2026-05-20 Jeffrey A. Hodgson , Hana Krasna , Aletha de Witt , Pfesesani van Zyl , Janeth Valverde

Photometric redshifts play an important role as a measure of distance for various cosmological topics. Spectroscopic redshifts are only available for a very limited number of objects but can be used for creating statistical models. A broad…

Instrumentation and Methods for Astrophysics · Physics 2016-08-30 Kai Lars Polsterer , Antonio D'Isanto , Fabian Gieseke

The high accuracy of modern space astrometry requires the use of General Relativity to model the propagation of stellar light through the gravitational field encountered from a source to a given observer inside the Solar System. In this…

General Relativity and Quantum Cosmology · Physics 2009-02-17 Mariateresa Crosta , Alberto Vecchiato

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…

Astrophysics · Physics 2007-05-23 P. Charlot , A. L. Fey , C. S. Jacobs , C. Ma , O. J. Sovers , A. Baudry

To investigate objects without a describable notion of distance, one can gather ordinal information by asking triplet comparisons of the form "Is object $x$ closer to $y$ or is $x$ closer to $z$?" In order to learn from such data, the…

Machine Learning · Computer Science 2019-06-28 Michael Lohaus , Philipp Hennig , Ulrike von Luxburg

A new list of physical characteristics of 4261 astrometric radio sources, including all 717 ICRF-Ext.2 sources has been compiled. Comparison of our data of optical characteristics with the official International Earth Rotation and Reference…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Oleg Titov , Zinovy Malkin

Current methods based on Neural Radiance Fields (NeRF) significantly lack the capacity to quantify uncertainty in their predictions, particularly on the unseen space including the occluded and outside scene content. This limitation hinders…

Computer Vision and Pattern Recognition · Computer Science 2023-11-28 Jianxiong Shen , Ruijie Ren , Adria Ruiz , Francesc Moreno-Noguer

The precise determination of the arrival direction of cosmic rays is a fundamental prerequisite for the search for sources or the study of their anisotropies on the sky. One of the most important aspects to achieve an optimal measurement of…

Astrophysics · Physics 2010-04-15 C. Bonifazi , A. Letessier-Selvon , E. M. Santos

Datasets collected from the open world unavoidably suffer from various forms of randomness or noiseness, leading to the ubiquity of aleatoric (data) uncertainty. Quantifying such uncertainty is particularly pivotal for object detection,…

Computer Vision and Pattern Recognition · Computer Science 2024-11-28 Peng Cui , Guande He , Dan Zhang , Zhijie Deng , Yinpeng Dong , Jun Zhu

We show that ensembling effectively quantifies model uncertainty in Neural Radiance Fields (NeRFs) if a density-aware epistemic uncertainty term is considered. The naive ensembles investigated in prior work simply average rendered RGB…

Computer Vision and Pattern Recognition · Computer Science 2022-09-20 Niko Sünderhauf , Jad Abou-Chakra , Dimity Miller

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…

Astrophysics · Physics 2009-11-10 E. B. Fomalont

Uncertainty quantification is a critical missing component in radio interferometric imaging that will only become increasingly important as the big-data era of radio interferometry emerges. Statistical sampling approaches to perform…

Instrumentation and Methods for Astrophysics · Physics 2018-09-12 Xiaohao Cai , Marcelo Pereyra , Jason D. McEwen

We present a versatile inequality of uncertainty relations which are useful when one approximates an observable and/or estimates a physical parameter based on the measurement of another observable. It is shown that the optimal choice for…

Quantum Physics · Physics 2016-07-22 Jaeha Lee , Izumi Tsutsui
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