Confusion regarding the term "nano-"

NASA Successfully Demonstrates Innovative Nanosatellite System

"The Mini AERCam prototype is just 7.5 inches in diameter and weighs only 10 pounds. The tiny free flyer is designed to be operated by on-orbit flight crews or by ground control personnel. Either could command the nanosatellite to fly automatic maneuvers."

Reader note: "NASA today issued a news release on its "Innovative Nanosatellite System." I was surprised that it was referring to the "volleyball-sized" Miniature Autonomous Extravehicular Robotic Camera. NASA should know better. A volleyball-sized machine is far from "nano" in scale."

Definitions of Nano on the Web:"A prefix meaning one-billionth."

Another reader notes that there is the set of satellite classifications for satellites listed on David Darling's (fascinating) website including:"nanosatellite: 1-10 Kg"

A note from Noel Hinners: "Keith: "Re the discussion about "confusion" in the usage of the term (prefix) "nano", there ought to be absolutely no confusion., especially in our profession. I've been railing in meetings against such prefix misuse for a couple of years now.

The Darling web site, however fascinating, perpetuates error with their particular and peculiar designation of satellite mass and equivalent terminology. The greatest sin there is using one order of magnitude difference to distinguish levels going from micro to nano to pico to femto. Students in science or engineering know those represent three orders of magnitude difference at each level. More to the point, it is a perversion of the prefixes to use them so out of context which is (usually) with reference to the International System of Units (SI) and mostly with reference to the meter or second or gram. Clearly what has happened is that some in NASA and elsewhere jumped on the pizzazz of nanotechnology in an attempt to be mod. After the problems with Mars Climate Orbiter and the units mix-up, one would think that NASA and the industry would abhor the misuse of the SI. Please refer your readers to the NIST website: http://physics.nist.gov/cuu/Units/prefixes.html for a neat table of prefixes and a link to prefixes for binary multiples (check out the kibibit). Thanks for listening - please help clear up this mess.

Noel" 

Reader comment: "The discussion about nanosatellites is interesting but for anyone working in the small satellite field there is no confusion about what a nanosatellite is. It is a spacecraft with a mass of 1 to 10 kilograms. It is a well accepted practice and if you review papers and conference proceedings from leading industry conferences such as the AIAA/USU Small Sat annual conference, the terms micro, nano and picosats are used all the time. http://www.smallsat.org/"