# Resource: Prefixes

All prefixes in the SI-system:^{[1,2]}

Prefixes | |||
---|---|---|---|

Yotta... | 1\,\mathrm Y\ldots | =10^{24}\ldots | 24 zeros (septillion) |

Zetta... | 1\,\mathrm Z\ldots | =10^{21}\ldots | 21 zeros (sextillion) |

Exa... | 1\,\mathrm E\ldots | =10^{18}\ldots | 18 zeros (quintillion) |

Peta... | 1\,\mathrm P\ldots | =10^{15}\ldots | 15 zeros (quadrillion) |

Tera... | 1\,\mathrm T\ldots | =10^{12}\ldots | 12 zeros (trillion) |

Giga... | 1\,\mathrm G\ldots | =10^{9}\ldots | 9 zeros (billion) |

Mega... | 1\,\mathrm M\ldots | =10^{6}\ldots | 6 zeros (million) |

Kilo... | 1\,\mathrm k\ldots | =10^{3}\ldots | 3 zeros (thousand) |

Hecto... | 1\,\mathrm h\ldots | =10^{2}\ldots | 2 zeros (hundred) |

Deka... | 1\,\mathrm {da}\ldots | =10^{1}\ldots | 1 zero (ten) |

Deci... | 1\,\mathrm {d}\ldots | =10^{-1}\ldots | 1 place after the point |

Centi... | 1\,\mathrm {c}\ldots | =10^{-2}\ldots | 2 places after the point |

Milli... | 1\,\mathrm {m}\ldots | =10^{-3}\ldots | 3 places after the point |

Micro... | 1\,\mathrm {\mu}\ldots | =10^{-6}\ldots | 6 places after the point |

Nano... | 1\,\mathrm {n}\ldots | =10^{-9}\ldots | 9 places after the point |

Pico... | 1\,\mathrm {p}\ldots | =10^{-12}\ldots | 12 places after the point |

Femto... | 1\,\mathrm {f}\ldots | =10^{-15}\ldots | 15 places after the point |

Atto... | 1\,\mathrm {a}\ldots | =10^{-18}\ldots | 18 places after the point |

Zepto... | 1\,\mathrm {z}\ldots | =10^{-21}\ldots | 21 places after the point |

Yocto... | 1\,\mathrm {y}\ldots | =10^{-24}\ldots | 24 places after the point |

Examples of magnitude scale for the prefixes (shown for size with the metre unit):^{1}

Size scale | ||
---|---|---|

Yottametres | \mathrm{Ym} | The universe^{5} |

Zettametres | \mathrm{Zm} | Galaxies^{4} |

Exametres | \mathrm{Em} | Nebulas^{[16]} |

Petametres | \mathrm{Pm} | Distance to nearest stars^{3} |

Terametres | \mathrm{Tm} | The solar system^{2} |

Gigametres | \mathrm{Gm} | The Sun^{[12]} |

Megametres | \mathrm{Mm} | The Earth^{[11]} |

Kilometres | \mathrm{km} | Mountains^{[10]} |

Hectometres | \mathrm{hm} | Buildings |

Dekametres | \mathrm{dam} | Trucks |

Decimetres | \mathrm{dm} | Books |

Centimetres | \mathrm{cm} | Coins |

Millimetres | \mathrm{mm} | Insects |

Micrometres | \mathrm{\mu m} | Bacteria^{[9]} |

Nanometres | \mathrm{nm} | Molecules^{[3]} |

Picometres | \mathrm{pm} | Atoms^{[3,8]} |

Femtometres | \mathrm{fm} | Protons^{[6,7]} |

Attometres | \mathrm{am} | Quarks^{[5]} |

Zeptometres | \mathrm{zm} | Smallest quark^{[4]} |

Yoctometres | \mathrm{ym} | Smallest particle^{[4,3]} |

A feeling of the size scale is shown in the Youtube video Power of Ten (1977) and can be interactively scrolled in in [4].

References:

- ‘
**The International System of Units (SI)**’ (book),*B. Inglis, J. Ullrich and others*, Bureau International des Poids et Mesures (BIPM), 9th ed., 2019, www.bipm.org/utils/common/pdf/si-brochure/SI-Brochure-9.pdf, chapter 3 - ‘
**Guide for the Use of the International System of Units (SI)**’ (article),*Ambler Thompson & Barry N. Taylor*, National Institute of Standards and Technology, 2008, physics.nist.gov/cuu/pdf/sp811.pdf - ‘
**Biotechnology**’ (book),*P. David Clark & Nanette J. Pazdernik*, Newnes, 2nd ed., 2015, books.google.de/books?id=osqcBAAAQBAJ, ISBN 9780123850164 - ‘
**The Scale of the Universe 2**’ (web page),*Cary Huang & Michael Huang*, htwins.net, 2012, www.htwins.net/scale2 (accessed May 3rd, 2019) - ‘
**Limits on the effective quark radius from inclusive ep scattering at HERA**’ (article),*H. Abramowicz, I. Abt and others*, Physics Letters B, vol. 757, 2016, linkinghub.elsevier.com/retrieve/pii/S0370269316300776, DOI 10.1016/j.physletb.2016.04.007 - ‘
**Electronics (+ and -) Protons, Photons, Neutrons, and Cosmic Rays**’ (book),*Robert Andrews Millikan*, Cambridge University Press, 1st ed., 1935, www.amazon.com/Electron-Protons-Photons-Neutron-Cosmic/dp/B00HSJGJTC - ‘
**The size of the proton**’ (web page),*Christine Nattrass*, Quantum Diaries, www.quantumdiaries.org/2010/07/12/the-size-of-the-proton (accessed May 3rd, 2019) - ‘
**Screening of membrane surface charges by divalent cations: an atomic representation**’ (article),*J. S. D’Arrigo*, American Journal of Physiology: Cell Physiology, vol. 235, issue 3, 1978, www.physiology.org/doi/10.1152/ajpcell.1978.235.3.C109, DOI 10.1152/ajpcell.1978.235.3.C109, pages 109–117 - ‘
**Small but Mighty: Cell Size and Bacteria**’ (article),*Petra Anne Levin (Department of Biology at Washington University) & Esther R. Angert (Department of Microbiology at Cornell University)*, Cold Spring Harbor Laboratory Press Biol, 2015, www.ncbi.nlm.nih.gov/pmc/articles/PMC4484965/pdf/cshperspect-CSZ-a019216.pdf, pages 2-3 - ‘
**Highest Mountain in the World**’ (web page), Geology.com, www.geology.com/records/highest-mountain-in-the-world.shtml (accessed May 3rd, 2019) - ‘
**How Big Is Earth?**’ (web page),*Tim Sharp*, Space.com, 2017, www.space.com/17638-how-big-is-earth.html (accessed May 3rd, 2019) - ‘
**The Sun**’ (web page), NASA, www.nasa.gov/sun (accessed May 3rd, 2019) - ‘
**Our Solar System, In Depth, Size and Distance**’ (web page), NASA, 2019, solarsystem.nasa.gov/solar-system/our-solar-system/in-depth (accessed May 3rd, 2019) - ‘
**PIA17046: Voyager Goes Interstellar**’ (web page), JPL-Caltech, NASA, Jet Propulsion Laboratory at California Institute of Technology, 2013, photojournal.jpl.nasa.gov/catalog/PIA17046 (accessed May 3rd, 2019) - ‘
**The Nearest Stars to Earth (Infographic)**’ (web page),*Karl Tate*, Space.com, 2012, www.space.com/18964-the-nearest-stars-to-earth-infographic.html (accessed May 3rd, 2019) - ‘
**30 Doradus (NGC 2070) (Tarantula Nebula)**’ (web page),*Robert Gendler*, Astrophotography by Robert Gendler, 2016, www.robgendlerastropics.com/30doradustext.html (accessed May 3rd, 2019) - ‘
**Our Milky Way Galaxy: How Big is Space?**’ (web page),*Pat Brennan*, NASA Exoplanet Exploration, 2019, exoplanets.nasa.gov/blog/1563/our-milky-way-galaxy-how-big-is-space (accessed May 3rd, 2019) - ‘
**Sizes of Galaxies**’ (web page), Sun.org, www.sun.org/images/sizes-of-galaxies (accessed May 3rd, 2019) - ‘
**Misconceptions about the Big Bang**’ (article),*Charles H. Lineweaver & Ramara M. Davis*, Scientific American, 2005, www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf, pages 36–45

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