A new Nature Climate Change study suggests airborne microplastics -- especially darker and colored particles -- are likely contributing to atmospheric warming by absorbing more heat than they reflect. Researchers estimate the effect could be roughly one-sixth that of black carbon, though outside experts say the uncertainties remain large and more study is needed before drawing firm policy conclusions. "We can say with confidence that overall they are warming agents," said Drew Shindell, a Duke University earth science professor and co-author of the study. "To me, that's the big advance." The Washington Post reports: To undertake their study, a group led by researchers at Fudan University in China examined how different colors and sizes of microplastics interact with light across the spectrum, while combining that information with simulations of how particles get dispersed in the air across the planet. "Black, yellow, blue and red [particles] absorb sunlight much more strongly than the white particles," Yu Liu, a Fudan professor and study co-author, said in a call with reporters. In fact, the study details how black and colored particles showed "absorption levels nearly 75 times higher than pristine, non-pigmented plastics." The scientists also found that different sizes of particles absorb light at different intensities -- and that how they absorb light can change as they age. The authors estimate that microplastics suspended in the atmosphere could be contributing to global warming at about one-sixth the amount of black carbon, also known as soot, a pollutant generated largely from burning fossil fuels. If the latest estimates are right, Shindell said, microplastics might not be an enormous source of atmospheric warming, compared with massive contributors such as cars and trucks, belching industrial plants or even burping cows. "But not a trivial one, either," he said. By his calculation, the effect of one year's microplastic emissions globally is approximately equivalent to 200 coal-fired power plants running for that year. But that rough estimate does not factor the longer-term repercussions of microplastics decaying and persisting in the environment for decades to come. Whatever the exact impact, the topic deserves further study, the authors say, because current climate modeling does not account for any additional warming that these tiny particles might be causing.

Read more of this story at Slashdot.

"The Associated Press is reporting on a new study in Nature Astronomy suggesting that a tiny, icy world beyond Pluto harbors a thin, delicate atmosphere that may have been created by volcanic eruptions or a comet strike," writes longtime Slashdot reader fahrbot-bot. From the report: Just 300 miles (500 kilometers) or so across, this mini Pluto is thought to be the solar system's smallest object yet with a clearly detected global atmosphere bound by gravity, said lead researcher Ko Arimatsu of the National Astronomical Observatory of Japan. This so-called minor planet -- formally known as (612533) 2002 XV93 -- is considered a plutino, circling the sun twice in the time it takes Neptune to complete three solar orbits. At the time of the study, it was more than 3.4 billion miles (5.5 billion kilometers) away, farther than even Pluto, the only other object in the Kuiper Belt with an observed atmosphere. This cosmic iceball's atmosphere is believed to be 5 million to 10 million times thinner than Earth's protective atmosphere, according to the the study [...]. It's 50 to 100 times thinner than even Pluto's tenuous atmosphere. The likeliest atmospheric chemicals are methane, nitrogen or carbon monoxide, any of which could reproduce the observed dimming as the object passed before the star, according to Arimatsu. Further observations, especially by NASA's Webb Space Telescope, could verify the makeup of the atmosphere, according to Arimatsu.

Read more of this story at Slashdot.

OpenAI president Greg Brockman's testimony dominated the fifth day of the trial for Elon Musk's lawsuit against the AI company. Brockman took the witness stand on Monday, disclosing that his stake in OpenAI is worth nearly $30 billion, despite not personally investing money in OpenAI. The judge also declined to admit a pretrial text in which Musk allegedly warned Brockman that he and Altman would become "the most hated men in America." From a report: Brockman's disclosure would put him on the Forbes list of the world's richest people, with wealth comparable to Melinda French Gates. [...] Late Sunday, OpenAI lawyers tried to admit as evidence a text message Musk sent to Brockman two days before the trial began. According to a court filing -- which did not include the actual text exchange -- Musk sent a message to Brockman to gauge interest in settlement. When Brockman replied that both sides should drop their respective claims, Musk shot back, according to the filing, "By the end of this week, you and Sam will be the most hated men in America. If you insist, so it will be." Judge Yvonne Gonzalez Rogers, who is overseeing the trial, did not admit the text exchange as evidence. Brockman acknowledged that he had promised to personally donate $100,000 to OpenAI's charity but never did. In explaining the delay, Brockman put the onus on Altman: "I asked Sam when I should donate this, and he said he would let me know," reports Business Insider. The first witness to testify on Monday was Stuart Russell, an artificial intelligence expert who teaches computer science at the University of California, Berkeley. "The most memorable part of Russell's testimony was when he talked about how much Musk's legal team paid him," notes Business Insider. "He received an eye-popping $5,000 per hour for 40 hours of preparatory work. Expert witnesses in high-profile cases typically make between $500 to $1,000 per hour." Recap: Musk Concludes Testimony At OpenAI Trial (Day Four) Elon Musk Says OpenAI Betrayed Him, Clashes With Company's Attorney (Day Three) Musk Testifies OpenAI Was Created As Nonprofit To Counter Google (Day Two) Elon Musk and OpenAI CEO Sam Altman Head To Court (Day One)

Read more of this story at Slashdot.