Wednesday, April 07, 2004

Really Tiny - Almost Ten To The Minus Avagadro
Scientists have developed a device able to measure the weight of a single cell, and they intend to weigh a virus next.

Made at Cornell University, it is a small cantilever whose vibration depends upon tiny masses placed on it.

The mass of a single cell of the E coli bacterium, they say in the Journal of Applied Physics, is 665 femtograms.

A femtogram is one-thousandth of a picogram, which is one-thousandth of a nanogram, which is a billionth of a gram.

The scale of the researcher's work is straining the number of prefixes needed to describe the world of the very small.

They have moved beyond the prefixes "nano", "pico" and "femto" to "atto," and now they have "zepto" in their sights. Officially zepto means one sextillionth of something, or one prefixed by 21 zeros.
Because they can?


Post a Comment

<< Home