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arXiv · 1111.1325

Light Deflection for relativistic space astrometry in closed form

Stefano Bertone·Christophe Le Poncin-Lafitte
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Abstract

Given the extreme accuracy reached by future global space astrometry, one needs a global relativistic modeling of observations. A relativistic definition of astrometric observables is then essential to find uniquely coordinates, parallax and proper motion of a stellar object. The standard procedure is to explicitly solve the null geodesic equations to describe the trajectory of a photon emitted by a celestial object and received by a moving observing satellite. However, this task can be avoided if one builds an astrometric set up using the recent formalism of time transfer functions.

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Stefano Bertone, Christophe Le Poncin-Lafitte. 2011-11-05. Light Deflection for relativistic space astrometry in closed form. https://arxiv.org/abs/1111.1325

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