What is the longest standard, systematically named unit routinely employed by astronomers?

Answer

Gigaparsec (Gpc)

The Gigaparsec, equivalent to one billion parsecs, is the largest systematically scaled unit commonly cited when mapping the largest known structures in the observable universe.

What is the longest standard, systematically named unit routinely employed by astronomers?

#Videos

What is Parsec ? How 1 parsec is measured? - YouTube

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