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That’s hella signatures

0.0000000000000001 helladollars?

By Michael Banks

“Yotta”, “zeta”, “exa” and “peta” could now be joined by a new number prefix, the “hella”, if a physics student from University of California, Davis, gets his way.

Austin Sendek has started a petition on the social networking site Facebook to establish a new, scientifically accepted prefix for 1027(that is 1 followed by 27 zeroes, or 1000000000000000000000000000).

Yotta (1024), which was established in 2001, is currently the largest number established in the International System of Units (SI) – the world’s most widely used system of measurement — with zeta (1021), exa (1018) and peta (1015) following close behind.

“Hella” comes from Californian slang for “very” or “a lot of”. Sendek says that by accepting the term the SI system can “not only rectify their failing prefix system but also honor the scientific progress of Northern California.”

The petition is gaining ground fast with over 20 0000 signatures (or “fans” on the Facebook page) – or 0.0000000000000000000002 hellafans.

So what could you use the hella for? Sendek claims it could be applied in many “crucial calculations”, including the wattage of the Sun (0.3 hellawatts), or the number of atoms in a large sample (6.02 hellaatoms in 120 kg of carbon-12).

Sendek has not said what he would like to call the number for 10-27 (10-24 is the yocto). So readers, any suggestions?

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  1. A. DeSouza

    For 1.0e-27, why not the “hello”? =)

  2. R. T. de Lima

    Hoola (10^-27)!

  3. (Chuckling)Yes, I agree why not ‘hello’?

  4. Mohammad Naisipour

    For 1.e27 I suggest “gapp” (گپ). It means very large in traditional persian language.

  5. Heh, it will lend to jokes about “hellava lot of ….”
    Perhaps “hilli” for the 10^-27?
    Mohammad: Since we’ve already got hella suggested for 10^27, try “gappa” (modified per comparison) for 10^30.

  6. Clayton

    1. Check your sig. figs. – I think it should be 6.02 hellaatoms, not 6 hellaatoms, in 120 kg of carbon-12; i.e. 3 sig. figs. in 120 kg?
    2. As for 1.e30, I like Mohammad’s suggestion, as modified by Neil. Mohammad, what’s the Persian term for ‘VERY small’? Maybe you could suggest it (keeping Neil’s idea in mind) for 1.e-27, and the Persian term for ‘extremely small’ for 1.e-30? What do you think?

  7. In 1994, Victor Mayes, writing in the Quarterly Journal of the Royal Astronomical Society (Vol.35, No.4) suggested a set of additional SI prefixes as follows:
    nava N (10^27),sansa S (10^30), besa B (10^33), vela (10^36), astra A (10^39), cata C (10^42), quinsa Q (10^45), and ultra U (10^48). He also advocated three new prefixes below yocto.
    These are: tiso t (10^-27), vindo v (10^-30), and weto w (10^-33).
    So we don’t need ‘hella’, as ‘nava’ will do nicely. Mayes derives these prefixes from various languages; e.g. ‘nava’ comes from the Sanskrit for nine. (10^27 = 1000^9). Examples of their use include: solar luminosity = 0.38 NW (NW = navawatt); electron rest mass = 0.91 tg (tg = tisogram). I have used these prefixes and found them very convenient. Let’s hope they can be made official.

  8. Joseph

    I think that is hella goes for 10^27 then 10^-27 should be cella or sella (as we already have cm). And Cellars are very useful!

  9. Sella’s good, but in the spirit of hella, surely 10^-27 should be lessa…

  10. smallsister

    What about a “whoppa”?

  11. There’s something wrong when you’re taking a dump and the only term that comes to mind is “Rock Lobster”


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