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  • Measure for Measure
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An anniversary annum

Nature Physics volume 22, page 172 (2026)Cite this article

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As our metrology column turns ten years, there is no better way to celebrate than to look at the definitions of a year, finds Stefanie Reichert.

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References

  1. Richards, E. G. in Explanatory Supplement to the Astronomical Almanac (eds Urban, S. E. & Seidelman, P. K.) 585–624 (University Science Books, 2012).

  2. Longstaff, A. Calendars from Around the World (National Maritime Museum, 2005); https://go.nature.com/4oYHQgE

  3. Gregorian calendar. PTB https://go.nature.com/48IMF91

  4. Sims, A. Saudi Arabia switches to ‘Western’ Gregorian calendar so it can pay workers less and save money. Independent (3 October 2016); https://go.nature.com/4qhmkER

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  1. Nature Physics https://www.nature.com/nphys/

    Stefanie Reichert

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  1. Stefanie Reichert
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Correspondence to Stefanie Reichert.

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Reichert, S. An anniversary annum. Nat. Phys. 22, 172 (2026). https://doi.org/10.1038/s41567-025-03152-9

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