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Exploring the Galaxy using space probes

Rasmus Bjoerk
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Abstract

This paper investigates the possible use of space probes to explore the Milky Way, as a means both of finding life elsewhere in the Galaxy and as finding an answer to the Fermi paradox. I simulate exploration of the Galaxy by first examining how long time it takes a given number of space probes to explore 40,000 stars in a box from -300 to 300 pc above the Galactic thin disk, as a function of Galactic radius. I then model the Galaxy to consist of $\sim{}260,000$ of these 40,000 stellar systems all located in a defined Galactic Habitable Zone and show how long time it takes to explore this zone. The result is that with 8 probes, each with 8 subprobes $\sim{}4%$ of the Galaxy can be explored in $2.92\cdot{}10^{8}$ years. Increasing the number of probes to 200, still with 8 subprobes each, reduces the exploration time to $1.52\cdot{}10^{7}$ years.

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Rasmus Bjoerk. 2007-04-23. Exploring the Galaxy using space probes. https://doi.org/10.1017/s1473550407003709

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