In article ,
Erik Max Francis writes:
From skimming papers on pulsar distances on Google, it looks like the
effective range is ~6 kpc, or perhaps ~2 kly.

Dropped a decimal the 6 kpc \approx 20000 LY. I agree with the
number, which is of course based on present Earth technology.

I think the point of the Pioneer and Voyager plaques was that any
advanced Galactic civilization would have a comprehensive map of
pulsars throughout the Galaxy and know their behavior over long spans
of time. _Given that information_, the probe's origin could be
located both in space and time.

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Steve Willner Phone 617-495-7123
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