The metric system is gaining new prefixes. Here’s what to know

Meet the metric system’s latest prefixes: ronna-, quetta-, ronto- and quecto-.

Adopted November 18 on the twenty seventh Normal Convention on Weights and Measures in Versailles, France, ronna- and quetta- describe exceedingly giant numbers whereas ronto- and quecto- describe the exceedingly small. That is the primary time that the Worldwide System of Items, or SI, has expanded since 1991, when the prefixes zetta-, yotta-, zepto and yocto- had been added (SN: 1/16/93).

Numerically, ronna- is 10²⁷ (that’s a digit adopted by 27 zeroes) and quetta- is 10³⁰ (30 zeroes). Their tiny counterparts ronto- and quecto- additionally confer with 27 and 30 zeroes, however these come after a decimal level. Till now, yotta- and yocto- (24 zeros) capped off the metric system’s vary.

Science News spoke with Richard Brown, head of metrology on the Nationwide Bodily Laboratory in Teddington, England, about what the most recent SI enlargement means for science. The next dialog has been edited for readability and brevity.

SN: Why do we’d like the brand new prefixes?

Brown: The amount of knowledge on the earth is growing exponentially. And we count on that to proceed to extend and doubtless speed up due to quantum computing, digitalization and issues like that. On the similar time, this amount of knowledge is beginning to get near the highest vary of the prefixes we at present use. Individuals begin to ask what comes subsequent?

SN: The place do the prefix names come from?

Brown: About 5 years in the past, I heard a BBC podcast about these new names for portions of knowledge. And the 2 that they talked about had been brontobyte and hellabyte. Brontobyte, I believe comes from brontosaurus being a giant dinosaur and hellabyte comes from “‘hell of a giant quantity.”

The issue with these from a metrology standpoint, or measurement standpoint, is they begin with letters B and H, which already are in use for different items and prefixes. So we are able to’t have these as names. [It was clear] that we needed to do one thing official as a result of folks had been beginning to want these prefixes. R and Q usually are not used for the rest, actually, by way of items or SI prefixes. [The prefix names themselves are] very, very loosely primarily based on the Greek and Latin names for 9 and 10.

SN: How will the prefixes be used?

Brown: The entire level of the Worldwide System of Items is it’s an accepted world system, which if you happen to use, you can be understood.

If you use a prefix with a unit, it signifies that the quantity related to the unit adjustments. And other people like small numbers that they will perceive. So you may categorical the mass of the Earth by way of ronnagrams; it’s six ronnagrams. And equally the mass of Jupiter is 2 quettagrams. Some good examples of [small numbers] are that the mass of an electron is about one rontogram, and the mass of 1 bit of knowledge as saved on a cell phone is round one quectogram.  

I believe using an appropriate prefix makes issues extra comprehensible. And I believe we shouldn’t neglect that even when there’s not all the time a direct scientific utilization instantly, they are going to achieve traction over time.