Intercontinental optical clock comparison sets stage to redefine the second

Researchers from around the world have completed the world’s largest, most demanding head-to-head comparison of clocks in history to build confidence for the upcoming redefinition of the second. The duration of a single second is currently defined by caesium (Cs) atomic clocks. Lasers ‘count’ the radiation emitted by Cs atoms in these devices to measure … Read more

In a first, enamel proteins 18-20 million years old from tropical, High Arctic sites unravel palaeobiology of extinct taxa

If obtaining sequences from ancient proteins found in fossils was previously limited to samples no older than four million years, two studies published in the journal Nature on Wednesday (July 9, 2025) have pushed back this timescale to more than 20 million years. The enamel proteins from extinct mammals are a staggering ten-fold older compared with the … Read more

ISRO successfully conducts hot tests of Gaganyaan propulsion system

According to ISRO, the Gaganyaan programme aims to demonstrate India’s capability to launch a crewed spacecraft into low Earth orbit. File. | Photo Credit: Reuters ISRO has successfully conducted two hot tests of the Gaganyaan Service Module Propulsion System (SMPS) at the space agency’s Propulsion Complex in Mahendragiri on July 3. The short-duration tests, lasting … Read more

How do atoms form? – The Hindu

Richard Feynman, a famous theoretical physicist who won the Nobel Prize, said that if he could pass on only one piece of scientific information to future generations, it would be that all things are made of atoms. Understanding how atoms form is a fundamental and important question, since they make up everything with mass. The … Read more

Rare earths emerge as a geopolitical lynchpin in the rising China-U.S. rivalry

“They’re going to deliver rare earths to us,” U.S. Commerce Secretary Howard Lutnick said in an interview on June 27. “And once they do that, we’ll take down our countermeasures.” Mr. Lutnick’s remarks came just a day after a White House official confirmed that the U.S. and China had reached “an additional understanding” to implement … Read more