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arXiv · 1408.3039

Enabling Gaia observations of naked-eye stars

J. Martín-Fleitas·A. Mora·J. Sahlmann·R. Kohley·B. Massart·J. L'hermitte·M. Le Roy·P. Paulet
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Abstract

The ESA Gaia space astrometry mission will perform an all-sky survey of stellar objects complete in the nominal magnitude range G = [6.0 - 20.0]. The stars with G lower than 6.0, i.e. those visible to the unaided human eye, would thus not be observed by Gaia. We present an algorithm configuration for the Gaia on-board autonomous object observation system that makes it possible to observe very bright stars with G = [2.0-6.0). Its performance has been tested during the in-orbit commissioning phase achieving an observation completeness of ~94% at G = 3 - 5.7 and ~75% at G = 2 - 3. Furthermore, two targeted observation techniques for data acquisition of stars brighter than G = 2.0 were tested. The capabilities of these two techniques and the results of the in-flight tests are presented. Although the astrometric performance for stars with G lower than 6.0 has yet to be established, it is clear that several science cases will benefit from the results of the work presented here.

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J. Martín-Fleitas, A. Mora, J. Sahlmann, R. Kohley, B. Massart, J. L'hermitte, M. Le Roy, P. Paulet. 2014-08-13. Enabling Gaia observations of naked-eye stars. https://doi.org/10.1117/12.2056325

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