zettametre

• (US) zettameter

zetta- +‎ metre

zettametre (plural zettametres)

1. 10²¹ metres
   • 1994, New Scientist - Volume 144, Issues 1951-1958, page 81:

     The largest known galaxy, at the centre of the Abell 2029 cluster in Virgo, has a diameter of around 53 zettametres.

   • 2015 August, Keith Atkin, “Time to ditch non-SI units in physics teaching?”, in Physics Education, volume 50, number 5:

     As one of my reviewers (SP Gray) puts it: '...I think that Andromeda will be a good deal closer to the Solar System than it is now, before we read of its distance in zettametres'

   • 2018, Margreth Tadie, Robert Pott, Neill Goosen, Petrie Van Wyk, Karin Elizabeth Wolff, “Expanding 1st year problem-solving skills through unit conversions and estimations”, in IEEE Global Engineering Education Conference (EDUCON):

     How many kiloparsecs are there in a zettametre (10²¹ m)?

• Zm (symbol)

• zettameter