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Catching a ride: using hypervelocity stars for interstellar and intergalactic travel

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Abstract

Hypervelocity stars are unique among the stars in the galaxy for their extreme velocities relative to the galactic center, in some cases achieving galactic escape velocity. Dozens of hypervelocity star candidates have been identified so far. One population includes B-type stars apparently ejected from the galactic core. A second population has been identified within the plane of the galaxy with no single origin. As a fast-moving energy source, hypervelocity stars could be uniquely valuable property in the galaxy for advanced civilizations. Given their potential for transportation and exploration across the plane of the galaxy or to other galaxies, they could serve as prime objects for Search for Extraterrestrial Intelligence (SETI) searches or as long- duration transports for far-future human exploratory missions. In addition, some hypervelocity stars may be entering our galaxy from extragalactic sources, making them possible mechanisms by which intelligences in neighboring galaxies could be exploring ours.
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