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Related papers: The astronomical units

200 papers

A body in Solar orbit beyond the Kuiper belt exhibits an annual parallax that exceeds its apparent proper motion by up to many orders of magnitude. Apparent motion of this body along the parallactic ellipse will deflect the angular position…

Astrophysics · Physics 2009-11-13 B. Scott Gaudi , Joshua S. Bloom

The age of the universe in the Big Bang model can be calculated from three parameters: Hubble's constant, h; the mass density of the universe, Omega_m; and the cosmological constant, Omega_lambda. Recent observations of the cosmic microwave…

Astrophysics · Physics 2009-06-16 Charles H. Lineweaver

Astrophysical measurements away from the 1 AU orbit of Earth can enable several astrophysical science cases that are challenging or impossible to perform from Earthbound platforms, including: building a detailed understanding of the…

Discussion of the designation of multiple-star components leads to a conclusion that, apart from components, we need to designate systems and centers-of-mass. The hierarchy is coded then by simple links to parent. This system is adopted in…

Astrophysics · Physics 2007-05-23 A. Tokovinin

In this review, the status of measurements of the matter density (Omega), the vaccuum energy density or cosmological constant (Lambda), the Hubble constant (H0), and ages of the oldest measured objects (t0) are summarized. Measurements of…

Astrophysics · Physics 2009-10-30 Wendy L. Freedman

During the last three decades, there has been a growing realization among physicists and cosmologists that the relation between particle physics and cosmology may constitute yet another successful example of the unity of science. However,…

Astrophysics · Physics 2007-05-23 Henrik Zinkernagel

The production of complex astronomical data is accelerating, especially with newer telescopes producing ever more large-scale surveys. The increased quantity, complexity, and variety of astronomical data demand a parallel increase in skill…

Instrumentation and Methods for Astrophysics · Physics 2024-11-25 Hyungsuk Tak , Yang Chen , Vinay L. Kashyap , Kaisey S. Mandel , Xiao-Li Meng , Aneta Siemiginowska , David A. van Dyk

The present naming convention for extrasolar planets used by the vast majority of researchers in the field is based upon an interpretation of the provisional I.A.U. standard for multiple star systems. With the existence of hundreds of…

Solar and Stellar Astrophysics · Physics 2010-12-06 F. V. Hessman , V. S. Dhillon , D. E. Winget , M. R. Schreiber , K. Horne , T. R. Marsh , E. Guenther , A. Schwope , U. Heber

The Hubble constant, which measures the expansion rate, together with the total energy density of the Universe, sets the size of the observable Universe, its age, and its radius of curvature. Excellent progress has been made recently toward…

Astrophysics · Physics 2008-11-26 Wendy L. Freedman

This document defines the high level metadata necessary to describe the physical parameter space of observed or simulated astronomical data sets, such as 2D-images, data cubes, X-ray event lists, IFU data, etc.. The Characterisation data…

Instrumentation and Methods for Astrophysics · Physics 2019-05-22 Mireille Louys , Anita Richards , Francois Bonnarel , Alberto Micol , Igor Chilingarian , Jonathan McDowell , the IVOA Data Model Working Group

A summary of various measurements of the mean matter density in the universe, Omega_m, is presented. Results from very different kinds of methods using various astronomical objects -- from supernovae to large-scale structure -- are shown.…

Astrophysics · Physics 2021-04-28 Sabine Schindler

We significantly constrain the sky position, distance, and mass of a possible additional, distant planet in the solar system by examining its influence on the distance between Earth and the Cassini Spacecraft. Our preferred region is…

Earth and Planetary Astrophysics · Physics 2016-10-05 Matthew J. Holman , Matthew J. Payne

We give an overview of the current understanding of Type Ia supernovae relevant for their use as cosmological distance indicators. We present the physical basis to understand their homogeneity of the observed light curves and spectra and…

Astrophysics · Physics 2015-06-24 P. Hoeflich , C. Gerardy , E. Linder , H. Marion

If the observed dark energy is a cosmological constant, the canonical state of the universe is de Sitter spacetime. In such a spacetime, quantum fluctuations that violate the null energy condition will create islands of matter that, if…

General Relativity and Quantum Cosmology · Physics 2009-04-30 Sourish Dutta , Tanmay Vachaspati

The treatment of angles within the SI is anomalous compared with other quantities, and there is a case for removing this anomaly by declaring plane angle to be an additional base quantity within the system. It is shown that this could bring…

Data Analysis, Statistics and Probability · Physics 2016-06-22 Paul Quincey , Richard J C Brown

It is considered the model of the homogeneous and isotropic universe. The scale of length is defined via the laboratory scale of time by the motion of photon. This leads to the appearance of the inertial forces. The properties of the space…

Astrophysics · Physics 2007-05-23 D. L. Khokhlov

The moon is receding from earth at an average rate of 3.8 cm/yr [6][7][9][12].This anomaly cannot be attributed to the well-known tidal exchange of angular momentum between earth and moon [8]. A secular change in the astronomical unit AU is…

General Physics · Physics 2010-01-09 M. Y. Amin

We review some results of the past 12 years derived from optical and infrared photometry of Type Ia supernovae. A combination of optical and infrared photometry allows us to determine accurately the extinction along the line of sight. The…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-01 Kevin Krisciunas

Recently collected SNIa data have been used to address the problem of measuring the cosmological parameters of the universe. Analysed in the framework of homogeneous models, they have yielded, as a primary result, a strictly positive…

Astrophysics · Physics 2007-05-23 Marie-Noëlle Célérier

Only astronomical observations can effectively probe in space-time the variabil ity of the physical dimensionless constants such as the fine structure constant and proton-to-electron mass ratio, \mu, which are related to fund amental forces…

Astrophysics · Physics 2007-12-31 Paolo Molaro
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