Browsing: Physics

Here’s a surprising fact: We don’t know what makes up 80 percent of the matter in the universe. I don’t mean that the matter is made of atoms, and we just don’t know which kind of atoms. What I mean is that four-fifths of the universe appears to be made of something that isn’t atoms at all, or more to the point, it’s not made from any of the fundamental particles that we know of. Why do we think that this mystery matter exists? The short answer is that Albert Einstein’s theory of gravity, general relativity, has painted us into a corner. When we look through telescopes at stars and galaxies moving through the universe, something we can’t see is…

Marie Curie is perhaps the most famous woman of 20th century science. Major motion pictures and best-selling biographies have chronicled her discovery of the radioactive elements polonium and radium, for which she shared the Nobel Prize in physics in 1903 and then received a second Nobel Prize, this time in chemistry, in 1911. Very little note, however, has been made of her leadership role in the development of radioactivity standards. In 1910, she was asked by her peers to prepare the world’s first radium standard: a glass ampoule containing 21.99 milligrams of radium chloride, whose mass and radioactivity had been carefully measured. She agreed, on the advice of Nobel laureate Ernest Rutherford, that this international standard would not be kept in…

In case you haven’t already heard, if you wanted to give your loved one that special, once-in-a-lifetime gift by naming one of the elements in row 7 of the Periodic Table after him or her, it’s too late (and probably against the rules anyway, but more on that later). With the recently announced official names for elements with atomic numbers 113 (nihonium), 115 (moscovium), 117 (tennessine) and 118 (oganesson), the all-radioactive row 7 of the Periodic Table is now complete. Included are two (thorium and uranium) found naturally, five that result from the radioactive decay of other elements—such as everyone’s favorite cinematic time machine fuel, plutonium—and 25 that can only be synthesized in the laboratory. The good news for those…

I’ve worked with many valuable materials in my career. Precious metals like gold and platinum, rare engineered nanomaterials, and fragile gemstones nearly as old as the Earth itself. But the unassuming jars of fine gray-brown powder I found myself holding last year left them all in the dust, so to speak. I think I probably kicked up some dust, too, when my colleague Ed Garboczi called to ask if I wanted to help him make some measurements of particles that the Apollo 11 and 14 astronauts had collected during their lunar landings. After all, when you get a call like that, you don’t walk, you run. Ed, a NIST Fellow and researcher in the Material Measurement Laboratory, and Jay Goguen of…

A catchphrase from a popular reality show goes: “One day you’re in. And the next day, you’re out.” For the purposes of the show, the host is referencing fashion. But the same could be said about science. With each new discovery or advance, an old theory or idea often becomes obsolete … or at least less important. We here in the NIST public affairs office thought it might be fun to list some of the NIST-relevant scientific ideas that we think are on their way in and out in 2017. While the items on the list below may not be as monumental as the discoveries that led to this year’s Nobel Prizes, MacArthur Foundation “genius” grants or Breakthrough Prizes, we…

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