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Local Interstellar Matter: The Apex Cloud

P. C. Frisch
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Abstract

Several nearby individual low column density interstellar cloudlets have been identified based on kinematical features evident in high-resolution CaII observations near the Sun. One of these cloudlets, the ``Aquila-Ophiuchus'' cloud, is within 5 pc of the Sun and located in the solar apex direction. The velocity vector of this Apex Cloud is reevaluated and components at this velocity are found towards 17 stars with distances 1--60 pc, and located primarily in the galactic center hemisphere. The Apex Cloud is the most likely candidate for the ``next'' interstellar cloud to be encountered by the Sun.

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P. C. Frisch. 2003-05-03. Local Interstellar Matter: The Apex Cloud. https://doi.org/10.1086/376684

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