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Crafted by the UK’s National Physical Laboratory in 2017, this tiny Christmas card is a huge deal. It’s said to be the world’s smallest seasonal greeting; it’s so small, in fact, that you can’t even see it without looking through a powerful microscope.

Measuring 15 micrometers wide and 20 micrometers tall, the card is 200 million times smaller than an ordinary postage stamp. The card is made from a 200-nanometer membrane of silicon nitride (typically used in ball bearings and integrated circuits) and coated with a 10-nanometer platinum layer. (A micrometer is a millionth of a meter, while a nanometer is a billionth of a meter.)

The card bears a snowman and “Seasons Greetings” on its front cover, and the message “Seasons Greetings From NPL” inside. The design and the text were engraved on the card using a focused ion beam.

Aside from showcasing the incredible tools that are used to work on small-scale materials and technologies, the researchers also crafted the card as “a fun way to mark the festive season.” (Hardly surprising, considering that this is the same institute that made the world’s smallest snowman—about 1/5 the width of a human hair—back in 2009.)

Today’s Science History Milestone: On December 27, 1831, Charles Darwin set sail aboard the 𝘏𝘔𝘚 𝘉𝘦𝘢𝘨𝘭𝘦, embarking on a five-year journey that enabled him to formulate his theory of evolution by natural selection.

Still remember your 5th-grade science classes? Test your knowledge and see if you still remember these facts and fundamental concepts in human anatomy, biology, botany, and other branches of science. Click here to try the “Are You Smarter Than A Pinoy Fifth-Grader” Challenge.

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  • https://www.livescience.com/61255-smallest-christmas-card.html
  • https://www.cnet.com/news/worlds-smallest-christmas-card-microscopic-national-physical-laboratory/
  • https://nypost.com/2017/12/18/this-might-be-the-worlds-smallest-christmas-card/
  • https://www.theengineer.co.uk/npl-makes-worlds-smallest-snowman/

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Author: Mikael Angelo Francisco

Bitten by the science writing bug, Mikael has years of writing and editorial experience under his belt. As the editor-in-chief of FlipScience, Mikael has sworn to help make science more fun and interesting for geeky readers and casual audiences alike.