Joe Palca Joe Palca is a science correspondent for NPR.
Joe Palca, photographed for NPR, 17 January 2019, in Washington DC.
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Joe Palca

Mars Has A New Visitor From Earth

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In this artist concept provided by NASA, the MAVEN spacecraft approaches Mars on a mission to study its upper atmosphere. AP hide caption

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AP

Mission To Study Mars' Climate Enters Red Planet's Orbit

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All folded up and ready to magnify: The Foldscope weighs less than two nickels, is small enough to fit in your back pocket and offers more than 2,000-fold magnification. TED/YouTube hide caption

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TED/YouTube

A $1 Microscope Folds From Paper With A Drop Of Glue

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The MD Brush has an unusual grip that automatically angles the brush head at 45 degrees. Meredith Rizzo/NPR hide caption

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Meredith Rizzo/NPR

Build A Toothbrush, Change The World. Or Not

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At The Nano Level, Wrinkles Aren't Always A No-No

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A prosthetic eye is a work of art custom-crafted for an individual. Rebecca Davis/NPR hide caption

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Rebecca Davis/NPR

Where We Learn That Artificial Eyes Really Aren't Round At All

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This little guy changes from flat sheet of paper to critter in about four minutes. Seth Kroll/Wyss Institute hide caption

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Seth Kroll/Wyss Institute

Transformer Paper Turns Itself Into A Robot. Cool!

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Scientists say a brief burst of radio activity has been detected at the Arecibo radio telescope in Puerto Rico. This new report resembles previous activity detected in Australia, which has scientist debating possible causes, including solar flares, blitzars, or something even more mysterious. Brian Negin/iStockphoto hide caption

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Brian Negin/iStockphoto

Close Encounters Of The Radio Kind? Mystery Bursts Baffle Astronomers

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Rosetta Spacecraft Readies For Rendezvous With Comet

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The solar panels of the International Space Station (ISS) are just one example of the many kinds of fragile scientific instruments that require inventive packing and deployment tricks. NASA hide caption

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NASA

To Make A Spacecraft That Folds And Unfolds, Try Origami

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Why Theories On Black Holes Are Full Of Holes

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Nasa Bends The Rules To Get Two Rovers To Mars

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If They Want To Make Anything, Proteins Must Know How To Fold

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The CRISPR enzyme (green and red) binds to a stretch of double-stranded DNA (purple and red), preparing to snip out the faulty part. Illustration courtesy of Jennifer Doudna/UC Berkeley hide caption

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Illustration courtesy of Jennifer Doudna/UC Berkeley

A CRISPR Way To Fix Faulty Genes

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One of 30 copies of the first protoype meter made by the International Bureau of Weights and Measures (BIPM) in Sevres, France. 1875-1889 NIST Museum Collection hide caption

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NIST Museum Collection

How Did The Meter Get Its Length?

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