[1] : Jargon File (4.3.1, 29 Jun 2001)

attoparsec n. about an inch. `atto-' is the standard si prefix for
   multiplication by 10^-18. a parsec parallax-second is 3.26
   light-years; an attoparsec is thus 3.26  10^-18 light years, or about
   3.1 cm thus, 1 attoparsec/microfortnight equals about 1 inch/sec.
   this unit is reported to be in use though probably not very seriously
   among hackers in the u.k. see micro-.


see also:
microfortnight micro- 

[2] : The Free On-line Dictionary of Computing (27 SEP 03)

attoparsec
     
         about 31 mm one inch.  "atto-" is the
        standard si prefix for multiplication by 10^-18.  a parsec
        parallax-second is 3.26 light-years; an attoparsec is thus
        3.26  10^-18 light years.  thus, one attoparsec per
        microfortnight is about one inch per second.
     
        this unit is reported to be in use though probably not very
        seriously among hackers in the uk.
     
        jargon file
     
        1996-12-08
     
     
see also:
si prefix microfortnight jargon file 

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