World Timekeepers Decide to Kill the Leap Second - CNET

Governments have voted to abolish the leap second immediately and replace it with a leap hour. Metrologists retire the leap second immediately, instead of by 2035. Credit: Alejandro Martinez Velez/Europa Press via GettyTime discrepancies that used to be adjusted by a jump of a second around once every 1.5 years will now wait until an hour needs correcting instead. Leap seconds serve to align time given by the sun’s position in the sky, which is based on Earth’s unsteady natural rotation, with the more stable ticking of atomic clocks, known as Universal Coordinated Time (UTC). But the rogue seconds have been a thorn in timekeepers' sides, disrupting computing systems and causing misalignment between clocks on the day they are implemented. Their replacement — a shift of an hour once Earth time and atomic time drift apart by 3,600 seconds — likely won’t be needed for thousands of years, effectively pushing the issue onto future generations. The leap second is dead. Long live the leap hour? Member states of the General Conference on Weights and Measures (CGPM) voted to pass the resolution at their 28th meeting, outside Paris, on 15 October.

Lawrence Livermore National Laboratory researcher Isaiah Santistevan led the development of three-dimensional simulations exploring how a nuclear device could deflect or disrupt an asteroid threatening Earth. Credit: Blaise Douros/LLNL Lawrence Livermore National Laboratory (LLNL) researchers are developing three-dimensional simulations to examine how a nuclear device could be used to deflect or potentially disrupt an asteroid threatening Earth.

Orcas are hunting great White Sharks around the world, scientists confirmThe killing of great whites by orcas has been reported in the waters of South Africa, California, and Australia, and the implications that the hunting behaviour would have on the marine ecosystem have been considered. In fact, it all started back on May 3, 2017, when the body of a female great white, weighing 1,100 kilograms, washed ashore in Gansbaai, close to Cape Town, with a deep gash through which its 90-kilogram liver had been extracted. Five more corpses of great whites appeared with similar wounds in the coming months, as claimed by shark biologist Alison Towner of Rhodes University. Two adult males, called Port and Starboard, who are supposed to be brothers judging by their dorsal fins that fold differently, were identified as the most probable perpetrators. The connection was officially established in 2022 based on video footage of a drone that caught three orcas chasing and biting a 3-meter great white off Mossel Bay. The sharks quickly disappeared from Dyer Island, one of the best places in the world to witness a great white.

Milky Way’s first microblazar candidate sits 12,000 light-years away, offering a rare ground-level lab for studying relativistic jetsA black hole 12,000 light-years away is firing a jet of plasma almost directly toward Earth. At that distance, no known or expected danger to Earth has been identified by the researchers or the institutions involved. What astronomers have actually found is rarer and more interesting than a threat. Researchers have identified IRAS 18293-0941 as a compelling candidate for the Milky Way’s first microblazar, a class of object that gives astrophysicists a close-up laboratory for studying some of the most violent physics in the galaxy. What Astronomers FoundThe discovery centers on a binary system whose black hole expels plasma jets at close to three-quarters the speed of light, pointed almost directly toward Earth. The system pairs a hot, massive star with a black hole that completes a full orbit roughly every 11.38 days. Material drawn from the companion star feeds the black hole, and some of that matter gets expelled outward as opposing jets traveling at approximately three-quarters the speed of light. Terminology matters here.

Forests that stood on Mozambique's coast thousands of years ago now lie beneath shallow seas, and they have become fish-filled "peat reefs" with marine life comparable to coral reefs, researchers report in Scientific Reports. A team from the Bazaruto Center for Scientific Studies (BCSS) Ocean Observatory, led by Mario Lebrato, documented the submerged peat in the Bazaruto Archipelago in the Western Indian Ocean. BCSS, founded in 2017, describes itself as Africa's first permanent ocean observatory. Working with universities and institutions in the U. K., U. S. and Canada, the team believes it has carried out the first ecological study of peat reefs anywhere in the tropics. Old forests, new seafloorRadiocarbon dating shows the peat formed between about 300 and 5,000 years ago, and chemical analysis indicates it came mostly from coastal land plants and trees. Some samples contain up to 40% organic carbon by dry weight. Lebrato said the coastline has very little natural hard seabed, mostly shifting sand. As rising seas expose the old peat layers, they create rare solid habitat where marine life can settle, hide and feed.