Mission to the Gravitational Focus of the Sun: A Critical Analysis

Geoffrey A. Landis

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arXiv · 1604.06351

Mission to the Gravitational Focus of the Sun: A Critical Analysis

Geoffrey A. Landis

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Abstract

The gravitational field of the sun will focus light from a distant source to a focal point at a minimal distance of 550 Astronomical Units from the sun. A proposed mission to this gravitational focus could use the sun as a very large lens, allowing (in principle) a large amplification of signal from the target, and a very high magnification. This article discusses some of the difficulties involved in using the sun as such a gravitational telescope for a candidate mission, that of imaging the surface of a previously-detected exoplanet. These difficulties include the pointing and focal length, and associated high magnification; the signal to noise ratio associated with the solar corona, and the focal blur. In addition, a method to calculate the signal gain and magnification is derived using the first-order deflection calculation and classical optics, showing that the gain is finite for an on-axis source of non-zero area.

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Geoffrey A. Landis. 2016-04-21. Mission to the Gravitational Focus of the Sun: A Critical Analysis. https://arxiv.org/abs/1604.06351

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