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Astronomers using the Vera C. Rubin Observatory have discovered a record-setting asteroid, known as 2025 MN45, nearly half a mile wide and spinning once every 1.88 minutes -- the fastest known rotation for an object of its size. "This is now the fastest-spinning asteroid that we know of, larger than 500 meters," said Sarah Greenstreet, University of Washington astronomer and lead author of the study. The findings have been published in the The Astrophysical Journal Letters. GeekWire reports: 2025 MN45 is one of more than 2,100 solar system objects that were detected during the observatory's commissioning phase. Over time, the LSST Camera tracked variations in the light reflected by those objects. Greenstreet and her colleagues analyzed those variations to determine the size, distance, composition and rate of rotation for 76 asteroids, all but one of which are in the main asteroid belt between the orbits of Mars and Jupiter. (The other asteroid is a near-Earth object.)
The team found 16 "super-fast rotators" spinning at rates ranging between 13 minutes and 2.2 hours per revolution -- plus three "ultra-fast rotators," including 2025 MN45, that make a full revolution in less than five minutes. Greenstreet said 2025 MN45 appears to consist of solid rock, as opposed to the "rubble pile" material that most asteroids are thought to be made of. "We also believe that it's likely a collisionary fragment of a much larger parent body that, early in the solar system's history, was heated enough that the material internal to it melted and differentiated," Greenstreet said. She and her colleagues suggest that the primordial collision blasted 2025 MN45 from the dense core of the parent body and sent it whirling into space.
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You must transfer at least $100,000 in assets to get a 4% match, with a minimum hold of 5 years to get the full payout (they break it up into installments with the last one being paid March 2031). Max funding is $2,000,000. You must transfer at least $2,000 in assets to get a 3% match, also with a minimum hold of 5 years. 4% is a very high bonus, but it is a long hold period. Be sure to read all the terms and conditions.
Longtime Slashdot reader schwit1 shares a report from Autoblog: ... the problem is that the federal brightness standards for automotive headlights have not changed for decades. The Federal Motor Vehicle Safety Standard No. 108 hasn't had significant updates since 1986, with an addition allowing Adaptive Driving Beam (ADB) headlights coming only in 2022. The NHTSA last investigated (PDF) the issue of headlamp glare in 2003. The current standards include huge loopholes for auto manufacturers to emit as much light as desired, as long as the manufacturer meets the requirements of the other parts of the regulation.
LEDs can be made to focus light using lasers, and auto manufacturers use this ability to their advantage. The regulatory standard prohibits excessive light in certain areas by referencing old technologies, but manufacturers design the areas in question to be shaded so that the total light output can still be increased greatly overall. Manufacturers want as much light as possible in order to get a high score for the IIHS headlight safety ratings. [...] Although the U.S. finally approved the ADB technology in 2022, manufacturers are wary of implementing it because of conflicting regulations, with a few exceptions, such as Rivian.
To fix this problem, the first step is to update Standard 108 with a cap on the maximum allowable brightness for LED technology. Next, states should begin requiring headlight alignment inspection during vehicle inspections. Finally, NHTSA should enforce a ban against the sale of aftermarket LEDs that exceed the allowed brightness, at least for on-road use. The Soft Lights Foundation has collected over 77,000 signatures calling for federal action to limit headlight brightness. People are frustrated with being temporarily blinded while driving, and it's high time some regulation was put into place. Vehicles have become cleaner and safer through smart regulation; the same just needs to be done with headlights.
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An anonymous reader quotes a report from the Associated Press: Japan's nuclear watchdog said Wednesday it is scrapping the safety screening for two reactors at the Hamaoka nuclear power plant in central Japan, after its operator was found to have fabricated data about earthquake risks. It was a setback to Japan's attempts to accelerate nuclear reactor restarts. Less than a quarter of commercial nuclear reactors are operational in the wake of the 2011 Fukushima Daiichi meltdowns, but rising energy costs and pressure to reduce carbon emissions have pushed the government to prioritize nuclear power.
Chubu Electric Power Co. had applied for safety screening to resume operations at the No. 3 and 4 reactors at the Hamaoka plant in 2014 and 2015. Two other reactors at the plant are being decommissioned, and a fifth is idle. The plant, about 200 kilometers (125 miles) west of Tokyo, is located on a coastal area known for potential risks from so-called Nankai Trough megaquakes. The Nuclear Regulation Authority said it started an internal investigation last February, after receiving a tip from a whistleblower that the utility had for years provided fabricated data that underestimated potential seismic risks. The regulator suspended the screening for the reactors after it confirmed the falsification and the utility acknowledged the fabrication in mid-December, said Shinsuke Yamanaka, the watchdog's chair. The NRA is also considering inspecting the utility headquarters.
[...] The scandal surfaced Monday when Chubu Electric President Kingo Hayashi acknowledged that workers at the utility used inappropriate seismic data with an alleged intention to underestimate seismic risks. He apologized and pledged to establish an independent panel for investigation. The screening, including data that had been approved earlier, would have to start from scratch or possibly be rejected entirely, Yamanaka said. The NRA will decide on the case next week, without waiting for the utility's probe results, he said. "Ensuring safety is the first and foremost responsibility for nuclear plant operators," Yamanaka said. "It is outrageous and it's a serious challenge to safety regulation."
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