"One way to help eliminate carbon emissions and thereby fight global warming may be to exploit fusion, the energy source of the sun and stars..." argues a new article in Bulletin of the Atomic Scientists (shared by Slashdot reader DanDrollette).

Though fusion energy would involve controllng a "plasma" gas of positively charged nuclei and negatively charged electrons heated to 150 million degrees Celsius, progress is being made — and the upside could be tremendous: One major advantage of using fusion as an energy source is that its underlying physics precludes either a fuel meltdown — such as what happened at Three Mile Island and Fukushima Daichi — or a runaway reaction, such as at Chernobyl. Furthermore, the amount of radioactive material that could be released in an accident in a fusion power plant system is much less than in a fission reactor. Consequently, a fusion system has much less capability to damage itself, and any damage would have much less dangerous consequences. As a result, current concepts for fusion systems may not necessitate an evacuation plan beyond the site boundary. Another advantage of fusion is that neither the fuel nor its products create the very long-lived radioactive waste that fission does, which means that fusion does not require long-term, geological storage...

When and how can fusion contribute to mitigating climate change? Private companies are in a hurry to develop fusion, and many say that they will be able to put commercial fusion power on the US electric grid in the early 2030s. The total private financing in this sector is impressive, at about $2 billion... After looking over the state of publicly and privately funded fusion research, the National Academies recommended that the United States embark upon a program to develop multiple preliminary designs for a fusion pilot plant by 2028, with the goal of putting a modest amount of net electricity on the U.S. electrical grid from a pilot plant starting sometime in the years between 2035 and 2040, use the pilot plant to study and develop technologies for fusion, and have a first-of-a-kind commercial fusion power plant operational by 2050. The United Kingdom has recently announced a plan to build a prototype fusion power plant by 2040. China has a plan to begin operation of a fusion engineering test reactor in the 2030s, while the European Union foresees operation of a demonstration fusion power plant in the 2050s...

We must look beyond the 2035 timeframe to see how fusion can make a major contribution, and how it can complement renewables... [P]roviding low-carbon electricity in the world market, including later in the century, is of great importance for holding climate change at bay.

An anonymous reader quotes a report from Phys.org: NASA and the nation's top federal nuclear research lab on Friday put out a request for proposals for a fission surface power system. NASA is collaborating with the U.S. Department of Energy's Idaho National Laboratory to establish a sun-independent power source for missions to the moon by the end of the decade. If successful in supporting a sustained human presence on the moon, the next objective would be Mars. NASA says fission surface power could provide sustained, abundant power no matter the environmental conditions on the moon or Mars. The reactor would be built on Earth and then sent to the moon.

Submitted plans for the fission surface power system should include a uranium-fueled reactor core, a system to convert the nuclear power into usable energy, a thermal management system to keep the reactor cool, and a distribution system providing no less than 40 kilowatts of continuous electric power for 10 years in the lunar environment. Some other requirements include that it be capable of turning itself off and on without human help, that it be able to operate from the deck of a lunar lander, and that it can be removed from the lander and run on a mobile system and be transported to a different lunar site for operation. Additionally, when launched from Earth to the moon, it should fit inside a 12-foot (4-meter) diameter cylinder that's 18 feet (6 meters) long. It should not weigh more than 13,200 pounds (6,000 kilograms). The proposal requests are for an initial system design and must be submitted by Feb. 19.

A new space mission to hunt for potentially habitable planets around Earth's closest neighbouring star system is under way. From a report: In a project with echoes of the 2009 film Avatar, an international collaboration of scientists in Australia and the US will search in the Alpha Centauri star system for earth-like planets that could sustain life. Alpha Centauri -- Earth's closest neighbouring star system -- consists of two sun-like stars, known as Alpha Centauri A and B, and a more distant red dwarf star. The Toliman mission, named after the ancient Arabic-derived name for the star system, will search for potential planets orbiting Alpha Centauri A and B.

The Toliman telescope, which is under construction, is set to be launched into low-earth orbit in 2023. It seeks to discover new planets in the "Goldilocks orbit" -- at the right distance, so the planet is neither too hot nor too cold to sustain life. Project leader Prof Peter Tuthill, of the University of Sydney, said: "If we're looking for life as we know it, usually the gold standard is a planet where liquid water could be present at the surface of the planet â" so it's not like a frozen snowball, and it doesn't boil all the water up into the atmosphere." "We know that life has evolved at least once, around a sun-like star on an earth-like planet," Tuthill said. "We try to look for other examples that are as close to that configuration as possible."

It's one of the most intriguing questions about the Solar System from the last five years: Is there a large planet, lurking out in the cold dark reaches, on an orbit so wide it could take 20,000 years to complete? The answer has proven elusive, but a new study reveals what could be traces of the mysterious hypothetical object's existence. From a report: Astronomer Michael Rowan-Robinson of Imperial College London in the UK conducted an analysis of data collected by the Infrared Astronomical Satellite (IRAS) in 1983, and found a trio of point sources that just might be Planet Nine. This, Rowan-Robinson concludes in his preprint paper, is actually fairly unlikely to be a real detection, but the possibility does mean that it could be used to model where the planet might be now in order to conduct a more targeted search, in the quest to confirm or rule out its existence. "Given the poor quality of the IRAS detections, at the very limit of the survey, and in a very difficult part of the sky for far infrared detections, the probability of the candidate being real is not overwhelming," he wrote.

"However, given the great interest of the Planet 9 hypothesis, it would be worthwhile to check whether an object with the proposed parameters and in the region of sky proposed, is inconsistent with the planetary ephemerides." Speculation about the existence of a hidden planet in the outer reaches of the Solar System has swirled for decades, but it reached a new pitch in 2016 with the publication of a paper proposing new evidence. Astronomers Mike Brown and Konstantin Batygin of Caltech found that small objects in the outer Solar System's Kuiper Belt were orbiting oddly, as though pushed into a pattern under the gravitational influence of something large.

But finding the dratted thing is a lot more complicated than it might sound. If it is out there, it could be five to 10 times the mass of Earth, orbiting at a distance somewhere between 400 and 800 astronomical units (an astronomical unit is the average distance between Earth and the Sun; Pluto, for context, is around 40 astronomical units from the Sun). This object is very far away, and quite small and cold and probably not reflecting much sunlight at all; and, moreover, we don't know exactly where in the very large sky it is. So the jury is out on whether it is real or not, and the topic is one of pretty intense and interesting debate. IRAS operated for 10 months from January 1983, taking a far-infrared survey of 96 percent of the sky. In this wavelength, small, cool objects like Planet Nine might be detectable, so Rowan-Robinson decided to re-analyze the data using parameters consistent with Planet Nine.

Scientists have identified what appears to be a small chunk of the moon that is tracking the Earth's orbit around the Sun. From a report: The asteroid, named Kamo'oalewa, was discovered in 2016 but until now relatively little has been known about it. New observations suggest it could be a fragment from the moon that was thrown into space by an ancient lunar collision. Kamo'oalewa is one of Earth's quasi-satellites, a category of asteroid that orbits the Sun, but remains relatively close to the planet -- in this case about 9m miles away.

Despite being close in astronomical terms, the asteroid is about the size of a ferris wheel and about 4m times fainter than the faintest star that can be seen with the naked eye. Consequently, the Earth's most powerful telescopes are needed to make observations. Using the Large Binocular Telescope on Mount Graham in southern Arizona, astronomers found the spectrum of reflected light from Kamo'oalewa closely matched lunar rocks from Nasa's Apollo missions, suggesting it originated from the moon. They had initially compared the light with that reflected off other near-Earth asteroids, but drawn a blank. "I looked through every near-Earth asteroid spectrum we had access to, and nothing matched," said Ben Sharkey, a PhD student at the University of Arizona and the paper's lead author.

nickwinlund77 shares a report from SciTechDaily: Since the first observation of merging black holes by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015, astronomers have been repeatedly surprised by their large masses. Though they emit no light, black hole mergers are observed through their emission of gravitational waves -- ripples in the fabric of spacetime that were predicted by Einstein's theory of general relativity. Physicists originally expected that black holes would have masses less than about 40 times that of the Sun, because merging black holes arise from massive stars, which can't hold themselves together if they get too big. The LIGO and Virgo observatories, however, have found many black holes with masses greater than that of 50 suns, with some as massive as 100 suns. Numerous formation scenarios have been proposed to produce such large black holes, but no single scenario has been able to explain the diversity of black hole mergers observed so far, and there is no agreement on which combination of formation scenarios is physically viable. This new study, published in the Astrophysical Journal Letters, is the first to show that both large and small black hole masses can result from a single pathway, wherein the black holes gain mass from the expansion of the universe itself.

Astronomers typically model black holes inside a universe that cannot expand. "It's an assumption that simplifies Einstein's equations because a universe that doesn't grow has much less to keep track of," said Kevin Croker, a professor at the UH Mnoa Department of Physics and Astronomy. "There is a trade-off though: predictions may only be reasonable for a limited amount of time." Because the individual events detectable by LIGO-Virgo only last a few seconds, when analyzing any single event, this simplification is sensible. But these same mergers are potentially billions of years in the making. During the time between the formation of a pair of black holes and their eventual merger, the universe grows profoundly. If the more subtle aspects of Einstein's theory are carefully considered, then a startling possibility emerges: the masses of black holes could grow in lockstep with the universe, a phenomenon that Croker and his team call cosmological coupling. The most well-known example of cosmologically-coupled material is light itself, which loses energy as the universe grows. "We thought to consider the opposite effect," said research co-author and UH Manoa Physics and Astronomy Professor Duncan Farrah. "What would LIGO -- Virgo observe if black holes were cosmologically coupled and gained energy without needing to consume other stars or gas?"

Long-time Slashdot reader fahrbot-bot shared this report from the New York Times about a "particularly unusual" star about 150 light-years away that's orbited by three planets: What's unusual is the inclinations of the outer two planets, HD 3167 c and d. Whereas in our solar system all the planets orbit in the same flat plane around the sun, these two are in polar orbits. That is, they go above and below their star's poles, rather than around the equator as Earth and the other planets in our system do.

Now scientists have discovered the system is even weirder than they thought. Researchers measured the orbit of the innermost planet, HD 3167 b, for the first time — and it doesn't match the other two. It instead orbits in the star's flat plane, like planets in our solar system, and perpendicular to HD 3167 c and d. This star system is the first one known to act like this...

The unusual configuration of HD 3167 highlights just how weird and wonderful other stars and their planets can be. "It puts in perspective again what we think we know about the formation of planetary systems," said Vincent Bourrier from the University of Geneva in Switzerland, who led the discovery published last month in the journal Astronomy & Astrophysics.

"Planets can evolve in really, really different ways."

Hecate Energy's plans for a 500-acre solar farm in upstate New York were cut by 50% "after facing an outcry from some in the community who feared the installation would mar the bucolic setting," reports the New York Times. (Alternate URL here.) The Copake fight mirrors similar battles raging across the country in rural areas like Lake County, Oregon; Clinton County, Ohio; and Troy, Texas. Developers say industrial-scale solar farms are needed to meet the nation's goals to mitigate the rise of climate change, but locals are fighting back against what they see as an encroachment on their pastoral settings, the loss of agricultural land and a decline in property values.

Until recently, most farms were built in the West, where abundant sunshine powers industrial-scale solar arrays and installations were farther away from sight lines. But now, with federal and state governments committing to a reduction in fossil fuels, joined by corporate giants like Amazon and Microsoft, the industry is seeking solar installations in areas where the calculus is more complicated... Improvements in the capabilities of the panels — including the development of so-called bifacial panels that capture the sun on both sides of a panel — allow for greater electricity generation in fewer panels, meaning a smaller footprint. Nonetheless, finding appropriate sites with sufficient sunlight, proximity to the grid and up-to-date infrastructure is challenging. Approximately 0.5 percent of U.S. land would need to be covered with solar panels to achieve the decarbonization goals proposed by the Biden administration in April, according to a study by the Energy Department. Urban settings usually lack enough space for significant projects; as a result, 90 percent of the suitable land sits in rural areas.

But even rural land is not entirely suitable. It needs to be in proximity to the electricity infrastructure that can add more power. The grade of land matters: Steeper slopes can be less efficient in the energy captured than flatter land. And wetlands are usually protected by federal or state law.

More important, development depends on owners willing to lease their property often for decades over the objection of neighbors.

theodp writes: Chicago Public School (CPS) teachers were 'blindsided' after access to popular classroom software was yanked due to CPS's interpretation of Illinois' Student Online Personal Protection Act (SOPPA), the Chicago Sun-Times reports. Sneha Dey writes, "Among the software products that violate the law, CPS now says, are programs like Code.org, which is widely used in computer science classes, and Adobe applications used for artistic design and newspaper page layouts. That left has many high school newspapers unable to produce their print editions. Also off limits is Scratch, software to create interactive stores, animations and games. CPS had partnered with the Scratch Foundation to hold family coding nights, among other events."

The Blueprint's Karen Buecking has more on how the new student data protection law has upended the computer science curriculum at CPS, noting that CPS teachers received an email from tech-backed Code.org explaining the situation: "We've already signed student data protection agreements with over 150 districts across the state to comply with the new law," said the Code.org representative. "The bad news is CPS's agreement and application process contains onerous requirements unrelated to student privacy that make it prohibitive for organizations like Code.org to agree to CPS's requirements as written."

A major solar flare erupted from the sun on Thursday in the strongest storm yet of our star's current weather cycle. Space.com reports: The sun fired off an X1-class solar flare, its most powerful kind of flare, that peaked at 11:35 a.m. EDT (1535 GMT), according to an alert from the U.S. Space Weather Prediction Center (SWPC), which tracks space weather events. The flare caused a temporary, but strong, radio blackout across the sunlit side of Earth centered on South America, the group wrote in an statement. NASA officials called the solar eruption a "significant solar flare," adding that it was captured in real-time video by the space agency's Solar Dynamics Observatory.

A coronal mass ejection from the flare, a huge eruption of charged particles, could reach Earth by Saturday or Sunday (Oct. 30-31), just in time for Halloween, SpaceWeather.com reported. The eruption could supercharge Earth's northern lights and potentially interfere with satellite-based communications. [...] Thursday's flare appeared to also spawn a coronal mass ejection, SWPC officials said. [...] The sun is in the early days of its current solar activity cycle, each of which lasts 11 years. The current cycle, called solar cycle 25, began in December 2019.

A possible Saturn-sized planet identified in the distant Whirlpool Galaxy could be the first exoplanet to be detected outside the Milky Way. From a report: The exoplanet candidate appears to be orbiting an X-ray binary -- made up of a normal star and a collapsed star or black hole -- with its distance from this binary roughly equivalent to the distance of Uranus from the sun. The discovery opens up a new window to search for exoplanets -- planets orbiting stars beyond our Sun -- at greater distances than ever before. Although nearly 5,000 exoplanets have been detected so far, all of them are in the Milky Way galaxy -- with few further than about 3,000 light years from Earth.

An exoplanet in the spiral Messier 51 (M51) galaxy -- also called the Whirlpool Galaxy because of its distinctive shape -- would be about 28m light years away. Dr Rosanne Di Stefano of the Center for Astrophysics at Harvard and Smithsonian in Cambridge, US, who led the research, said: "Since the 1750s, it has been conjectured that the dim distant nebulas, now called galaxies, are island universes: large, gravitationally-bound stellar populations similar to our home, the Milky Way. Our discovery of the planet candidate ... gives us the first peek into external populations of planetary systems, extending the reach of planet searches to distances roughly 10,000 times more distant."

"Humanity will return to the lunar surface in 2024 as part of the Artemis program," writes the Auto Evolution site. "However, before NASA begins shuttling people to our natural satellite, it has to build a network there that will go beyond Earth's low orbit and connect space to Earth in a sort of Internet connection..." The network's name? LunaNet: Astronauts will be able to use the LunaNet via numerous nodes and communicate with the crew on and around the Moon in the same manner that we use Wi-Fi here on Earth. In addition, missions using the network will have access to position and time signals, allowing astronauts and rovers to navigate the rugged lunar terrain and return to their base. LunaNet will also use space-weather instruments to identify potentially dangerous solar activity, such as flares that erupt from the Sun and send harsh radiation towards the astronauts. With this new connectivity, the crew can be directly alerted. This will cut down the time it takes for network management on Earth to do so. These warnings will be comparable to the ones we receive on our phones when there is hazardous weather. The architecture's capabilities will also include a lunar search and rescue capability...

Researchers could also use LunaNet antennas to peer into deep space and search for radio signals from distant celestial objects. Altogether, the architecture's capabilities will give scientists a new platform to test space theories, allowing them to extend their scientific knowledge. Recently, NASA released the "Draft LunaNet Interoperability Specification" in order to kickstart the development of this new "lunar internet." Technical discussions among industry experts from around the world are expected to follow.

"In our new paper, published in Nature, we report the discovery of the first known exoplanet to survive the death of its star without having its orbit altered by other planets moving around -- circling a distance comparable to those between the Sun and the Solar System planets," writes one of the study's authors, Dimitri Veras, in an article for The Conversation. From the report: This new exoplanet, which we discovered with the Keck Observatory in Hawaii, is particularly similar to Jupiter in both mass and orbital separation, and provides us with a crucial snapshot into planetary survivors around dying stars. A star's transformation into a white dwarf involves a violent phase in which it becomes a bloated "red giant," also known as a "giant branch" star, hundreds of times bigger than before. We believe that this exoplanet only just survived: if it was initially closer to its parent star, it would have been engulfed by the star's expansion. When the Sun eventually becomes a red giant, its radius will actually reach outwards to Earth's current orbit. That means the Sun will (probably) engulf Mercury and Venus, and possibly the Earth -- but we are not sure.

Jupiter, and its moons, have been expected to survive, although we previously didn't know for sure. But with our discovery of this new exoplanet, we can now be more certain that Jupiter really will make it. Moreover, the margin of error in the position of this exoplanet could mean that it is almost half as close to the white dwarf as Jupiter currently is to the Sun. If so, that is additional evidence for assuming that Jupiter, and Mars, will make it. So could any life survive this transformation? A white dwarf could power life on moons or planets that end up being very close to it (about one-tenth the distance between the Sun and Mercury) for the first few billion years. After that, there wouldn't be enough radiation to sustain anything. [...]

The new white dwarf exoplanet was found with what is known as the microlensing detection method. This looks at how light bends due to a strong gravitational field, which happens when a star momentarily aligns with a more distant star, as seen from Earth. The gravity from the foreground star magnifies the light from the star behind it. Any planets orbiting the star in the foreground will bend and warp this magnified light, which is how we can detect them. The white dwarf we investigated is one-quarter of the way towards the centre of the Milky Way galaxy, or about 6,500 light years away from our Solar System, and the more distant star is in the centre of the galaxy.

China's Five-hundred-meter Aperture Spherical radio Telescope has detected more than 1,600 fast radio bursts from a single enigmatic system. From a report: Fast radio bursts, or FRBs, are one of the greatest mysteries of our universe. Coming from deep space, these outbursts can flash and fade in a matter of milliseconds, yet in each instance can release as much energy as the sun does in a year. They pop up all across the sky multiple times a day, but most appear to be one-off events and are thus hard to catch. First discovered in 2007, FRBs have challenged and tantalized scientists seeking to uncover their obscure origins and to use them as unique tools for probing the depths of intergalactic space. Now, using the world's largest single-dish radio telescope, an international team has reported the largest set of FRB events ever detected in history.

According to their paper published in Nature today, between August and October 2019 the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwestern China recorded a total of 1,652 such brief and bright outbursts from a single repeating FRB source in a dwarf galaxy three billion light years away. Besides dramatically boosting the total number of known FRB events, the observations also revealed a very wide range of brightnesses among the recorded events, offering new clues about the astrophysical nature of their mysterious source. "The study is very thorough, with a level of details and sensitivity we've never had before," says astrophysicist Emily Petroff from the University of Amsterdam in the Netherlands and McGill University in Canada, who is not involved in the research. "Such in-depth analyses of individual sources will be a top priority in FRB research in the near future."

Amid an escalating crisis, the power source offers a dream -- or a pipe dream -- of limitless clean energy. From a report: Let's say that you've devoted your entire adult life to developing a carbon-free way to power a household for a year on the fuel of a single glass of water, and that you've had moments, even years, when you were pretty sure you would succeed. Let's say also that you're not crazy. This is a reasonable description of many of the physicists working in the field of nuclear fusion. In order to reach this goal, they had to find a way to heat matter to temperatures hotter than the center of the sun, so hot that atoms essentially melt into a cloud of charged particles known as plasma; they did that. They had to conceive of and build containers that could hold those plasmas; they did that, too, by making "bottles" out of strong magnetic fields. When those magnetic bottles leaked -- because, as one scientist explained, trying to contain plasma in a magnetic bottle is like trying to wrap a jelly in twine -- they had to devise further ingenious solutions, and, again and again, they did. Over decades, in the pursuit of nuclear fusion, scientists and engineers built giant metal doughnuts and Gehryesque twisted coils, they "pinched" plasmas with lasers, and they constructed fusion devices in garages. For thirty-six years, they have been planning and building an experimental fusion device in Provence. And yet commercially viable nuclear-fusion energy has always remained just a bit farther on.

As the White Queen, in "Through the Looking Glass," said to Alice, it is never jam today, it is always jam tomorrow. The accelerating climate crisis makes fusion's elusiveness more than cutely maddening. Solar energy gets more efficient and affordable each year, but it's not continuously available, and it still relies on gas power plants for distribution. The same is true for wind power. Conventional nuclear power has extremely well-known disadvantages. Carbon capture, which is like a toothbrush for the sky, is compelling, but after you capture a teraton or two of carbon there's nowhere to put it. All these tools figure extensively in decarbonization plans laid out by groups like the Intergovernmental Panel on Climate Change, but, according to those plans, even when combined with one another the tools are insufficient. Fusion remains the great clean-energy dream -- or, depending on whom you ask, pipe dream. Fusion, theoretically, has no scarcity issues; our planet has enough of fusion's primary fuels, heavy hydrogen and lithium, which are found in seawater, to last thirty million years.

Fusion requires no major advances in batteries, it would be available on demand, it wouldn't cause the next Fukushima, and it wouldn't be too pricey -- if only we could figure out all the "details." (A joke I heard is that fusion operates according to the law of the "conservation of difficulty": when one problem is solved, a new one of equal difficulty emerges to take its place.) The details are tremendously complex, and the people who work to figure them out have for years been dealing with their own scarcities -- scarcities of funding and scarcities of faith. Fusion, as of now, has no place in the Green New Deal. In 1976, the U.S. Energy Research and Development Administration published a study predicting how quickly nuclear fusion could become a reality, depending on how much money was invested in the field. For around nine billion a year in today's dollars -- described as the "Maximum Effective Effort" -- it projected reaching fusion energy by 1990. The scale descended to about a billion dollars a year, which the study projected would lead to "Fusion Never." "And that's about what's been spent," the British physicist Steven Cowley told me. "Pretty close to the maximum amount you could spend in order to never get there."

It's been 10 years since the death of Steve Jobs. Michael Dell talks about his memories of the tech icon, including when Jobs tried to convince Dell to license Mac software to run on Intel-based PCs. CNET reports: Fast forward to 1993. Jobs, ousted from Apple after a fallout with the company's board in 1985, had started a new company, called Next, and created a beautiful (but expensive) workstation, with its own operating system, as well as software called WebObjects for building web-based applications. Dell says Jobs came to his house in Texas several times that year, trying to convince him to use the Next operating system on Dell PCs, by arguing that it was better than Microsoft's Windows software and could undermine the Unix workstation market being touted by Sun Microsystems. The problem, Dell says he told Jobs, was that there were no applications for it and zero customer interest. Still, Dell's company worked a little bit with Next and used WebObjects to build its first online store in the mid-'90s.

In 1997, Jobs rejoined a struggling Apple after it acquired Next for $429 million, and he pitched Dell on another business proposal (as Jobs was evaluating Apple's Mac clone licensing project, which he ultimately shut down). Jobs and his team had ported the Mac software, based on Next's Mach operating system, and had it running on the Intel x86 chips that powered Dell PCs. Jobs offered to license the Mac OS to Dell, telling him he could give PC buyers a choice of Apple's software or Microsoft's Windows OS installed on their machine. "He said, look at this -- we've got this Dell desktop and it's running Mac OS," Dell tells me. "Why don't you license the Mac OS?" Dell thought it was a great idea and told Jobs he'd pay a licensing fee for every PC sold with the Mac OS. But Jobs had a counteroffer: He was worried that licensing scheme might undermine Apple's own Mac computer sales because Dell computers were less costly. Instead, Dell says, Jobs suggested he just load the Mac OS alongside Windows on every Dell PC and let customers decide which software to use -- and then pay Apple for every Dell PC sold.

Dell smiles when he tells the story. "The royalty he was talking about would amount to hundreds of millions of dollars, and the math just didn't work, because most of our customers, especially larger business customers, didn't really want the Mac operating system," he writes. "Steve's proposal would have been interesting if it was just us saying, "OK, we'll pay you every time we use the Mac OS" -- but to pay him for every time we didn't use it ... well, nice try, Steve!" Another problem: Jobs wouldn't guarantee access to the Mac OS three, four or five years later "even on the same bad terms." That could leave customers who were using Mac OS out of luck as the software evolved, leaving Dell Inc. no way to ensure it could support those users. Still, Dell acknowledges the deal was a what-could-have-been moment in history. [...] That different direction led to Jobs continuing to evolve the Next-inspired Mac OS and retooling the Mac product line, including adding the candy-colored iMac in mid-1998.

Earth is losing some of its glow, a study published in Geophysical Research Letters last week shows. It appears climate change and a natural climate shift have essentially scuffed up our planet. From a report: The study takes a look at earthshine, or the light reflected from the planet that casts a faint light on the surface of the Moon. It's also known as the Da Vinci Glow, because Leonardo da Vinci was the first person to formally write about it. Research has advanced quite a bit since da Vinci's writing 500 years ago, and the new findings use two decades of earthshine data collected at Big Bear Solar Observatory using a special type of telescope to view the Moon. The best time to observe earthshine is when the Moon is waxing or waning. Look at the Moon then, and you may be able to make out a faint outline of the whole Moon in addition to the sliver brightly illuminated by the Sun. That ghostly outline is thanks to earthshine, caused by the sunlight reflecting off our planet.

The observatory is perfectly situated to measure earthshine for 40% of the planet, spanning the Pacific and parts of North America. Analyzing the data for roughly 800 nights between 1998 and 2017 showed a small but significant decline in earthshine. There were some year-to-year shifts, but the paper notes that those are "quite muted, with a long-term decline dominating the time series." The scientists used satellite data to gauge what drove the dimming. Land, ice, clouds, and open ocean all have different levels of reflectivity that contribute to earthshine. (The reflectivity of different surfaces is also referred to as albedo.) The findings point to the disappearance of clouds in the tropical Pacific as the culprit in dulling Earth's shine. "The albedo drop was such a surprise to us when we analyzed the last three years of data after 17 years of nearly flat albedo," said Philip Goode, a researcher at New Jersey Institute of Technology and the lead author of the report, in a statement.

A spacecraft bound for the planet Mercury will take a first look at the target tonight, when it makes its first-ever flyby of the small rocky world during an incredibly close encounter tonight. Space.com reports: The mission, called BepiColombo, is a joint project of the European Space Agency (ESA) and the Japanese Aerospace Exploration Agency (JAXA). It is only the second mission in history sent to orbit Mercury, the smallest and innermost planet of the solar system. BepiColombo's flyby tonight (Oct. 1) will bring the spacecraft within just 124 miles (200 kilometers) of the surface of Mercury, the closest the probe will ever get to the planet during its mission. The first images from the encounter are expected to reach Earth early Saturday (Oct. 2) and will be the first close images of Mercury's scorched surface since the end of NASA's Messenger orbiter mission in 2015.

BepiColombo will make its closest approach to Mercury at 7:34 p.m. EDT (2334 GMT) today (Oct.1), ESA said in a statement. The spacecraft will then continue on its winding trajectory around the sun. This close pass is one of nine gravity-assist flybys, maneuvers that use the gravity of celestial bodies to adjust a spacecraft's trajectory, that BepiColombo needs to perform before it can enter its target orbit around the planet. This flyby, however, will take the spacecraft even closer to the scorched planet's surface, than its ultimate scientific orbit of 300 to 930 miles (480 to 1,500 kilometers). The $750 million BepiColombo mission will be able to make measurements of the environment around the planet and take images with its black and white 'selfie' cameras, which provide a 1024 by 1024 pixel resolution (comparable to an early-2000s flip phone.) [...] After tonight's close pass, it will take four more flybys of Mercury by BepiColombo before the spacecraft is in the correct position to finally enter the planet's orbit, which is set to happen in 2025.

GW Ori is a star system 1,300 light years from Earth in the constellation of Orion. It is surrounded by a huge disk of dust and gas, a common feature of young star systems that are forming planets. But fascinatingly, it is a system with not one star, but three. From a report: As if that were not intriguing enough, GW Ori's disk is split in two, almost like Saturn's rings if they had a massive gap in between. And to make it even more bizarre, the outer ring is tilted at about 38 degrees. Scientists have been trying to explain what is going on there. Some hypothesized that the gap in the disk could be the result of one or more planets forming in the system. If so, this would be the first known planet that orbits three stars at once, also known as a circumtriple planet.

Now the GW Ori system has been modeled in greater detail, and researchers say a planet -- a gassy world as massive as Jupiter -- is the best explanation for the gap in the dust cloud. Although the planet itself cannot be seen, astronomers may be witnessing it carve out its orbit in its first million years of its existence. A paper on the finding was published in September in the Monthly Notices of the Royal Astronomical Society. The scientists say it disproves an alternative explanation -- that the gravitational torque of the stars cleared the space in the disk. Their paper suggests there is not enough turbulence in the disk, known as its viscosity, for this explanation to suffice The finding also highlights how much more there is to learn about the unexpected ways in which planets can form.

America's federally-owned electric utility, the Tennessee Valley Authority, has spent billions of dollars with nothing to show for it, reports the Chattanooga Times Free Press.

"Nearly 47 years after construction began on the Bellefonte Nuclear Power Plant in Northeast Alabama, the Tennessee Valley Authority is giving up its construction permit for America's biggest unfinished nuclear plant and abandoning any plans to complete the twin-reactor facility..." Giving up the construction permit at Bellefonte signals the end of any new nuclear plant construction at TVA with only seven of the 17 nuclear reactors the utility once planned to build ever completed.... Since the 1970s, a total of 95 nuclear reactors proposed to be built by U.S. utilities have been canceled due to rising construction costs, slowing power demand and cheapening power alternatives.

The NRC now regulates 93 remaining commercial nuclear reactors at 56 nuclear power plants, including TVA's Sequoyah and Watts Bar nuclear plants in East Tennessee and the Browns Ferry nuclear plant in Athens, Alabama. Collectively, those nuclear plants provide more than 40% of TVA's power and over 20% of the nation's electricity supply... TVA spokesman Jim Hopson said in the past two decades, the growth in power demand in the Tennessee Valley has continued to slow as more energy efficiency measures have been adopted and the price of natural gas, solar power and additional hydroelectric generation has declined in competition with nuclear.
Thanks to long-time Slashdot reader The Real Dr John for sharing the story. And today the Chattanooga Times Free Press opinions editor offered this suggestion: TVA still owns the 1,600-acre site, as well as the plant that has never — and likely now will never — generate the first spark of nuclear-produced electricity. But that doesn't mean it can't make power some other way. A gas plant? Uggh. A wind field? Seems unlikely given the stillness of North Alabama. A solar plant? That could be more of a possibility. All of the transmission equipment and the electrical grid is at the ready...

By now — after siting, building, scrapping, building again, abandoning, putting up for sale, agreeing to sell for pennies on the dollar and finally going to court to defend not selling the Bellefonte Nuclear Plant — TVA ratepayers and taxpayers have lost somewhere between $6 billion (according to TVA) and $9 billion (according to a 2018 letter from five congressmen)... TVA spokesman Jim Hopson said Wednesday that TVA is making no decisions immediately. "But we're not taking anything off the table," he added...

Hopson said TVA's May 2021 "strategic intent and guiding principles" notes the utility has solar commitments to date of more than 2,300 megawatts of solar capacity expected to come online by the end of 2023. Including those projects, TVA expects to add 10,000 megawatts of solar power by 2035 — a 24-fold increase from today.

That 10,000 megawatts of solar power would be equal to more than eight would-be Bellefonte reactors.