An anonymous reader quotes a report from Interesting Engineering: A student has successfully developed a small nuclear fusion reactor as part of his A-Levels. The 17-year-old built the reactor to generate neutrons as part of his Extended Project Qualification (EPQ). Notably, Cesare Mencarini's work is claimed to be the only nuclear reactor built in a school environment. Showcased at the Cambridge Science Festival recently, the nuclear reactor achieved plasma a few months ago. It also gave Mencarini an A* in his A-Level results, according to reports. [...] Mencarini maintained that the goal of the reactor is to create conditions that are required for fusion. However, the project couldn't get same pressure that's generated by the Sun due to its own gravity. Therefore, to make atoms hot enough, the teen used high voltage.

The reactor achieved plasma in June. "Two days ago I achieved plasma, which was brilliant and I'm massively happy about this," wrote Mencarini in a LinkedIn post. "The system is running thanks to a Leybold Trivac E2 roughing pump, which allows me to achieve a minimum pressure of 8E-3 Torr." At that time, he mentioned that Pfeiffer TPH062 would be used later to achieve fusion. "This turbomolecular pump is currently isolated by a VAT Throttling Valve." "The grid is then attached to a 30kV rated High Voltage Feedthrough connected to a 5kV Unilab power supply, which allows me to use the fusor in my school (It is limited to a 2mA output). While running the fusor I experimented with 2 grids which you can see in the images," added Mencarini in the post.

Ars Technica's John Timmer reports: [T]he International Astronomical Union has a resolution that calls for a "Lunar Celestial Reference System" and "Lunar Coordinate Time" to handle things there. On Monday, two researchers at the National institute of Standards and Technology, Neil Ashby and Bijunath Patla, did the math to show how this might work. [...] Ashby and Patla worked on developing a system where anything can be calculated in reference to the center of mass of the Earth/Moon system. Or, as they put it in the paper, their mathematical system "enables us to compare clock rates on the Moon and cislunar Lagrange points with respect to clocks on Earth by using a metric appropriate for a locally freely falling frame such as the center of mass of the Earth-Moon system in the Sun's gravitational field." What does this look like? Well, a lot of deriving equations. The paper's body has 55 of them, and there are another 67 in the appendices. So, a lot of the paper ends up looking like this.

Things get complicated because there are so many factors to consider. There are tidal effects from the Sun and other planets. Anything on the surface of the Earth or Moon is moving due to rotation; other objects are moving while in orbit. The gravitational influence on time will depend on where an object is located. So, there's a lot to keep track of. Ashby and Patla don't have to take everything into account in all circumstances. Some of these factors are so small they'll only be detectable with an extremely high-precision clock. Others tend to cancel each other out. Still, using their system, they're able to calculate that an object near the surface of the Moon will pick up an extra 56 microseconds every day, which is a problem in situations where we may be relying on measuring time with nanosecond precision. And the researchers say that their approach, while focused on the Earth/Moon system, is still generalizable. Which means that it should be possible to modify it and create a frame of reference that would work on both Earth and anywhere else in the Solar System. Which, given the pace at which we've sent things beyond low-Earth orbit, is probably a healthy amount of future-proofing. The findings have been published in the Astronomical Journal. A National Institute of Standards and Technology (NIST) press release announcing the work can be found here.

sciencehabit shares a report from Science.org: For years, astronomers thought it was the Milky Way's destiny to collide with its near neighbor the Andromeda galaxy a few billion years from now. But a new simulation finds a 50% chance the impending crunch will end up a near-miss, at least for the next 10 billion years. It's been known that Andromeda is heading toward our home Galaxy since 1912, heading pretty much straight at the Milky Way at a speed of 110 kilometers per second. Such galaxy mergers, which can be seen in progress elsewhere in the universe, are spectacularly messy affairs. Although most stars survive unscathed, the galaxies' spiral structures are obliterated, sending streams of stars spinning off into space. After billions of years, the merged galaxies typically settle into a single elliptical galaxy: a giant featureless blob of stars. A study from 2008 suggested a Milky Way-Andromeda merger was inevitable within the next 5 billion years, and that in the process the Sun and Earth would get gravitationally grabbed by Andromeda for a time before ending up in the distant outer suburbs of the resulting elliptical, which the researchers dub "Milkomeda."

In the new simulation, researchers made use of the most recent and best estimates of the motion and mass of the four largest galaxies in the Local Group. They then plugged those into simulations developed by the Institute for Computational Cosmology at Durham University. First, they ran the simulation including just the Milky Way and Andromeda and found that they merged in slightly less than half of the cases -- lower odds than other recent estimates. When they included the effect of the Triangulum galaxy, the Local Group's third largest, the merger probability increased to about two-thirds. But with the inclusion of the Large Magellanic Cloud, a satellite galaxy of the Milky Way that is the fourth largest in the Local Group, those chances dropped back down to a coin flip. And if the cosmic smashup does happen, it won't be for about 8 billion years. "As it stands, proclamations of the impending demise of our Galaxy appear greatly exaggerated," the researchers write. Meanwhile, if the accelerating expansion of the universe continues unabated, all other galaxies will disappear beyond our cosmic event horizon, leaving Milkomeda as the sole occupant of the visible universe. The study is available as a preprint on arXiv.

Slashdot reader sciencehabit shared this report from Science magazine: One of the classic tropes of science fiction is terraforming Mars: warming up our cold neighbor so it could support human civilization. The idea might not be so far-fetched, research published today in Science Advances suggests...

Samaneh Ansari [a Ph.D. student at Northwestern University and lead author on the new study] and her colleagues wanted to test the heat-trapping abilities of a substance Mars holds in abundance: dust. Martian dust is rich in iron and aluminum, which give it its characteristic red hue. But its microscopic size and roughly spherical shape are not conducive to absorbing radiation or reflecting it back to the surface. So the researchers brainstormed a different particle: using the iron and aluminum in the dust to manufacture 9-micrometer-long rods, about twice as big as a speck of martian dust and smaller than commercially available glitter. Ansari designed a simulation to test how these theoretical particles would interact with light. She found "unexpectedly huge effects" in how they absorbed infrared radiation from the surface and how they scattered that radiation back down to Mars — key factors that determine whether an aerosol particle creates a greenhouse effect.

Collaborators at the University of Chicago and the University of Central Florida then fed the particles into computer models of Mars's climate. They examined the effect of annually injecting 2 million tons of the rods 10 to 100 meters above the surface, where they would be lofted to higher altitudes by turbulent winds and settle out of the atmosphere 10 times more slowly than natural Mars dust. Mars could warm by about 10 degreesC within a matter of months, the team found, despite requiring 5000 times less material than other proposed greenhouse gas schemes...

Still, "Increasing the temperature of the planet is just one of the things that we would need to do in order to live on Mars without any assistance," says Juan Alday, a postdoctoral planetary science researcher at the Open University not involved with the work. For one, the amount of oxygen in Mars's atmosphere is only 0.1%, compared with 21% on Earth. The pressure on Mars is also 150 times lower than on Earth, which would cause human blood to boil. And Mars has no ozone layer, which means there is no protection from the Sun's harmful ultraviolet radiation. What's more, even once warmed, martian soils may still be too salty or toxic to grow crops. In other words, McInnes says, upping the temperature "isn't some kind of magic switch" that would make Mars habitable.

That isn't stopping Ansari and her colleagues from investigating the possibilities.

According to a recent study, SpaceX's new Starlink direct-to-cell (DTC) satellites are nearly five times brighter than traditional Starlinks due to their lower orbit. While these satellites offer the promise of widespread connectivity, their increased brightness poses challenges for astronomical observations, prompting SpaceX to consider applying brightness mitigation techniques. Space.com reports: The higher luminosity of these DTCs compared to regular Starlinks is partly because they circle Earth at just 217 miles (350 kilometers) above the surface, which is lower than traditional Starlink internet satellites, whose altitude is 340 miles (550 kilometers), the study reported. [...] At the time the study was conducted, SpaceX had not yet applied its routine brightness mitigation techniques to the DTCs, such as adjusting their chassis and solar panels to reduce the portion of spacecraft illuminated by the sun, study lead author Anthony Mallama of the IAU Centre for the Protection of Dark and Quiet Skies from Satellite Constellation Interference (IAU-CPS) told Space.com.

SpaceX began applying brightness mitigation techniques to regular Starlinks in 2020, after astronomers voiced serious concerns about the satellites' trails streaking across telescope images, rendering them unusable. Prior to launch, the company now applies a mirror-like dielectric surface to the underside of each Starlink chassis, to help reflect sunlight into space rather than scattering it toward Earth. Post launch, the company adjusts spacecraft chassis and solar panels to further reduce luminosity. Together, these techniques are very effective, reducing Starlink satellites' brightness by a factor of 10, Mallama said. If SpaceX applies these brightness mitigation techniques to the DTCs, which are nearly the same size as the regular Starlinks, the DTCs would still be 2.6 times brighter than their traditional counterparts, Mallama and his colleagues reported in the recent study, which was reviewed internally by IAU-CPS and posted to the preprint server arXiv last month.

However, while DTCs are brighter objects, they move at a faster apparent rate and spend more time in Earth's shadow than regular Starlinks, which would offset some of their negative impact on astronomy observations, the study noted. "I see it as a tradeoff in parameters rather than an absolute better/worse kind of situation," John Barentine, a principal consultant at Arizona-based Dark Sky Consulting who was not involved with the new study, told Space.com.

Scientists studying lunar samples brought back by the Apollo missions have determined that the moon's thin atmosphere is produced largely by meteorite impacts. "Our findings provide a clearer picture of how the moon's surface and atmosphere interact over long timescales, [and] enhance our understanding of space weathering processes," said Dr Nicole Nie, the co-author of the new study based at MIT's department of Earth, atmospheric, and planetary sciences. The Guardian reports: Writing in the journal Science Advances, Nie and her colleagues describe how the lunar atmosphere must be constantly replenished because its atoms are continuously being lost to space, primarily because of the moon's weak gravity, or trapped on the lunar surface. Ultraviolet photons from the sun can rerelease the latter, but the researchers say replenishment of the atmosphere is thought to rely on atoms being released from within lunar minerals -- either via vaporisation by meteorite impacts, or by solar wind sputtering, a process in which charged particles from the sun hit the moon and eject atoms. But which of the two factors dominates had been unclear, with data from Nasa's lunar atmosphere and dust environment explorer, launched in 2013, suggesting both were at play.

Nie and colleagues unpicked the conundrum by studying the different forms, or isotopes, of potassium and rubidium in 10 samples of lunar soil from the Apollo missions. The team say meteorite impacts and solar wind sputtering both favor the release of lighter forms of the elements, but that the actual proportion of heavy to light isotopes that end up in the lunar atmosphere and soil would differ depending on the process. "After measuring the isotopic compositions of lunar soils, we built a mathematical model taking into account various space weathering processes, and solve for the contribution of each of them by matching the measured isotopic compositions," said Nie. The results suggest about 70% of the moon's atmosphere is down to impact vaporization and 30% to solar wind sputtering.

Longtime Slashdot reader Uncle_Meataxe shares a report from the Sacramento Bee: California's power grid handled a nearly three week long record-setting heat wave with few issues. The heat wave was the hottest 20-day period on record around Sacramento and set an all-time temperature record of 124 degrees in Palm Springs. Emergency alerts and calls for voluntary conservation were avoided this time around. Officials credit years of investment in renewable energy, especially battery storage that store solar power for use when the sun stops shining.

CAISO last issued calls for voluntary conservation two years ago, during a 2022 bout of extreme heat. Since then, roughly 11,600 megawatts of new renewable energy sources have come onto California's electricity grid. That includes 10,000 megawatts of battery power, enough to power 10 million homes for a few hours. California is now home to the most grid batteries in the world outside of China, [said Elliot Mainzer, president and CEO of California Independent System Operator (CAISO)].

"Batteries performed very well in this event, they were charged and ready at the right times for optimization on the grid," he added. "That made a big, big difference." [...] Apart from battery storage, Mainzer also credited that success to less extreme temperatures in Southern California as well as noticeable slightly lower electricity consumption in the peak demand hours, from 4 p.m. to 9 p.m.

An anonymous reader shared this report from ScienceAlert: NASA's Parker Solar Probe, tasked with taking a close-up look at the Sun's outer corona, has just equalled the record for the fastest-moving human-made object ever. The previous record holder? The Parker Solar Probe, again. The probe was recorded traveling at 635,266 kilometers (394,736 miles) per hour on June 29, the second time it's reached that speed since it launched in 2018. We're talking around 500 times faster than the speed of sound here. It's on course to get even faster too, with a top speed of around 692,000 kph (430,000 mph) expected when it makes its closest approach to the Sun in 2025.
It's the probe's 20th approach to the sun, according to the article, with the probe using Venus "to create a sort of gravity-powered slingshot," according to the article. (NASA has created a nice interactive 3D model of the probe...)

Besides collecting particle samples in 2021, "The probe is eventually going to get nice and close to the swirling mass of ultra-hot plasma surrounding the Sun, and take a wealth of different measurements to help improve our scientific understanding of it."

A group of astronomers want to change the definition of a planet. Their new proposed definition wouldn't bring Pluto back into the planetary fold, but it could reclassify thousands of celestial bodies across the universe. From a report: The International Astronomical Union's (IAU) current definition of a planet, established in 2006, includes only celestial bodies that are nearly round, are gravitationally dominant and orbit our Sun. This Sun-centric definition excludes all of the bodies we've discovered outside our solar system, even if they may fit all other parameters. They are instead considered exoplanets. Those behind the new proposal critiqued the IAU's definition in an upcoming paper in the Planetary Science Journal, arguing it's vague, not quantitative and unnecessarily exclusionary.

Their new proposal would instead classify planets based on their mass, considering a planet to be any celestial body that:
1. orbits one or more stars, brown dwarfs or stellar remnants and,
is more massive than 10ÂÂ kilograms (kg) and,
is less massive than 13 Jupiter masses (2.5 X 10^28Âkg).

What if across the bottom of the Atlantic Ocean, six high-voltage power cables stretched — each over 2,000 miles long.

CNN reports that a group of entrepreneurs "wants to build what would be the world's largest subsea energy interconnector between continents, linking Europe and North America...to connect places like the United Kingdom's west with eastern Canada, and potentially New York with western France...

"The Europe-US cables could send 6 gigawatts of energy in both directions at the speed of light, said Laurent Segalen, founder of the London-based Megawatt-X renewable energy firm, who is also part of the trio proposing the transatlantic interconnector. That's equivalent to what six large-scale nuclear power plants can generate, transmitted in near-real time." The interconnector would send renewable energy both east and west, taking advantage of the sun's diurnal journey across the sky. "When the sun is at its zenith, we probably have more power in Europe than we can really use," said Simon Ludlam, founder and CEO of Etchea Energy, and one of the trio of Europeans leading the project. "We've got wind and we've also got too much solar. That's a good time to send it to a demand center, like the East Coast of the United States. Five, six hours later, it's the zenith in the East Coast, and obviously, we in Europe have come back for dinner, and we get the reverse flow," he added.

The transatlantic interconnector is still a proposal, but networks of green energy cables are starting to sprawl across the world's sea beds. They are fast becoming part of a global climate solution, transmitting large amounts of renewable energy to countries struggling to make the green transition alone. But they are also forging new relations that are reshaping the geopolitical map and shifting some of the world's energy wars down to the depths of the ocean...

Already, energy cables run between several countries in Europe, most of them allied neighbors. Not all of them carry renewable power exclusively — that's sometimes determined by what makes up each country's energy grid — âbut new ones are typically being built for a green energy future. The UK, where land space for power plants is limited, is already connected with Belgium, Norway, the Netherlands and Denmark under the sea. It has signed up to a solar and wind link with Morocco to take advantage of the North African country's many hours of sunlight and strong trade winds that run across the equator. Similar proposals are popping up around the globe. A project called Sun Cable seeks to send solar power from sunny Australia, where land is abundant, to the Southeast Asian nation of Singapore, which also has plenty of sun but very little room for solar farms. India and Saudi Arabia plan to link their respective power grids via the Arabian Sea, part of a broader economic corridor plan to connect Asia, the Middle East and Europe.

In November of 2022, "More than 800 people were selected to participate in the Denver Basic Income Project," reports the Colorado Sun, "while they were living on the streets, in shelters, on friends' couches or in vehicles.

One group received $1,000 a month, according to the article, while a second group received $6,500 in the first month, and then $500 for the next 11 months. (And a "control" group received $50 a month.) Amazingly, about 45% of participants in all three groups "were living in a house or apartment that they rented or owned by the study's 10-month check-in point, according to the research." The number of nights spent in shelters among participants in the first and second groups decreased by half. And participants in those two groups reported an increase in full-time work, while the control group reported decreased full-time employment. The project also saved tax dollars, according to the report. Researchers tallied an estimated $589,214 in savings on public services, including ambulance rides, visits to hospital emergency departments, jail stays and shelter nights...

The study, which began in November 2022 with payments to the first group of participants, has been extended for an additional eight months, until September, and organizers are attempting to raise money to extend it further.

"The Short Happy Reign of the CD-ROM" was just one article in a Fast Company series called 1994 Week. As the week rolled along they also re-visited Yahoo, Netscape, and how the U.S. Congress "forced the videogame industry to grow up."

But another article argues that it's in web pages from 1994 that "you can start to see in those weird, formative years some surprising signs of what the web would be, and what it could be." It's hard to say precisely when the tipping point was. Many point to September '93, when AOL users first flooded Usenet. But the web entered a new phase the following year. According to an MIT study, at the start of 1994, there were just 623 web servers. By year's end, it was estimated there were at least 10,000, hosting new sites including Yahoo!, the White House, the Library of Congress, Snopes, the BBC, sex.com, and something called The Amazing FishCam. The number of servers globally was doubling every two months. No one had seen growth quite like that before. According to a press release announcing the start of the World Wide Web Foundation that October, this network of pages "was widely considered to be the fastest-growing network phenomenon of all time."

As the year began, Web pages were by and large personal and intimate, made by research institutions, communities, or individuals, not companies or brands. Many pages embodied the spirit, or extended the presence, of newsgroups on Usenet, or "User's Net." (Snopes and the Internet Movie Database, which landed on the Web in 1993, began as crowd-sourced projects on Usenet.) But a number of big companies, including Microsoft, Sun, Apple, IBM, and Wells Fargo, established their first modest Web outposts in 1994, a hint of the shopping malls and content farms and slop factories and strip mines to come. 1994 also marked the start of banner ads and online transactions (a CD, pizzas), and the birth of spam and phishing...

[B]ack in '94, the salesmen and oilmen and land-grabbers and developers had barely arrived. In the calm before the storm, the Web was still weird, unruly, unpredictable, and fascinating to look at and get lost in. People around the world weren't just writing and illustrating these pages, they were coding and designing them. For the most part, the design was non-design. With a few eye-popping exceptions, formatting and layout choices were simple, haphazard, personal, and — in contrast to most of today's web — irrepressibly charming. There were no table layouts yet; cascading style sheets, though first proposed in October 1994 by Norwegian programmer Håkon Wium Lie, wouldn't arrive until December 1996... The highways and megalopolises would come later, courtesy of some of the world's biggest corporations and increasingly peopled by bots, but in 1994 the internet was still intimate, made by and for individuals... Soon, many people would add "under construction" signs to their Web pages, like a friendly request to pardon our dust. It was a reminder that someone was working on it — another indication of the craft and care that was going into this never-ending quilt of knowledge.
The article includes screenshots of Netscape in action from browser-emulating site OldWeb.Today (albeit without using a 14.4 kbps modems). "Look in and think about how and why this web grew the way it did, and what could have been. Or try to imagine what life was like when the web wasn't worldwide yet, and no one knew what it really was."

Slashdot reader tedlistens calls it "a trip down memory lane," offering "some telling glimpses of the future, and some lessons for it too." The article revisits 1994 sites like Global Network Navigator, Time-Warner's Pathfinder, and Wired's online site HotWired as well as 30-year-old versions of the home pages for Wells Fargo and Microsoft.

What did they miss? Share your own memories in the comments.

What do you remember about the web in 1994?

Jonathan O'Callaghan reports via Scientific American: Despite more than a century of efforts to show otherwise, it seems Albert Einstein can still do no wrong. Or at least that's the case for his special theory of relativity, which predicts that time ticks slower for objects moving at extremely high speeds. Called time dilation, this effect grows in intensity the closer to the speed of light that something travels, but it is strangely subjective: a passenger on an accelerating starship would experience time passing normally, but external observers would see the starship moving ever slower as its speed approached that of light. As counterintuitive as this effect may be, it has been checked and confirmed in the motions of everything from Earth-orbiting satellites far-distant galaxies. Now a group of scientists have taken such tests one step further by observing more than 1,500 supernovae across the universe to reveal time dilation's effects on a staggering cosmic scale. The researchers' findings, once again, reach an all-too-familiar conclusion. "Einstein is right one more time," says Geraint Lewis of the University of Sydney, a co-author of the study.

In the paper, posted earlier this month on the preprint server arXiv.org, Ryan White of the University of Queensland in Australia and his colleagues used data from the Dark Energy Survey (DES) to investigate time dilation. For the past decade, researchers involved with DES had used the Victor M. Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile to study particular exploding stars called Type 1a supernovae across billions of years of cosmic history. [...] Type 1a supernovae are keystone cosmic explosions caused when a white dwarf -- the slowly cooling corpse of a midsized star -- siphons so much material from a companion that it ignites a thermonuclear reaction and explodes. This explosion occurs once the growing white dwarf reaches about 1.44 times the mass of our sun, a threshold known as the Chandrasekhar limit. This physical baseline imbues all Type 1a supernovae with a fairly consistent brightness, making them useful cosmic beacons for gauging intergalactic distances. "They should all be essentially the same kind of event no matter where you look in the universe," White says. "They all come from exploding white dwarf stars, which happens at almost exactly the same mass no matter where they are."

The steadfastness of these supernovae across the entire observable universe is what makes them potent probes of time dilation -- nothing else, in principle, should so radically and precisely slow their apparent progression in lockstep with ever-greater distances. Using the dataset of 1,504 supernovae from DES, White's paper shows with astonishing accuracy that this correlation holds true out to a redshift of 1.2, a time when the universe was about five billion years old. "This is the most precise measurement" of cosmological time dilation yet, White says, up to seven times more precise than previous measurements of cosmological time dilation that used fewer supernovae. [...] This particular supernova-focused facet of the Dark Energy Survey has concluded, so until a new dataset is taken, White's measurement of cosmological time dilation is unlikely to be beaten. "It's a pretty definitive measurement," says [Tamara Davis of the University of Queensland, a co-author of the paper]. "You don't really need to do any better." Jonathan O'Callaghan is an award-winning freelance journalist covering astronomy, astrophysics, commercial spaceflight and space exploration.

Ancient Slashdot reader ewhac writes: On June 19, 1984, Robert Scheifler announced on MIT's Project Athena mailing list a new graphical windowing system he'd put together. Having cribbed a fair bit of code from the existing windowing toolkit called W, Scheifler named his new system X, thus giving birth to the X Window System. Scheifler prophetically wrote at the time, "The code seems fairly solid at this point, although there are still some deficiencies to be fixed up."

The 1980's and 1990's saw tremendous activity in the development of graphical displays and user interfaces, and X was right in the middle of it all, alongside Apple, Sun, Xerox, Apollo, Silicon Graphics, NeXT, and many others. Despite the fierce, well-funded competition, and heated arguments about how many buttons a mouse should have, X managed to survive, due in large part to its Open Source licensing and its flexible design, allowing it to continue to work well even as graphical hardware rapidly advanced. As such, it was ported to dozens of platforms over the years (including a port to the Amiga computer by Dale Luck in the late 1980's). 40 years later, despite its warts, inconsistencies, age, and Wayland promising for the last ten years to be coming Real Soon Now, X remains the windowing system for UNIX-like platforms.

Astronomers are observing the sudden awakening of a giant black hole in the constellation of Virgo. "Decades of observations found nothing remarkable about the distant galaxy in the constellation of Virgo, but that changed at the end of 2019 when astronomers noticed a dramatic surge in its luminosity that persists to this day," reports The Guardian. "Researchers now believe they are witnessing changes that have never been seen before, with the black hole at the galaxy's core putting on an extreme cosmic light show as vast amounts of material fall into it." From the report: The galaxy, which goes by the snappy codename SDSS1335+0728 and lies 300m light years away, was flagged to astronomers in December 2019 when an observatory in California called the Zwicky Transient Facility recorded a sudden rise in its brightness. The alert prompted a flurry of new observations and checks of archived measurements from ground- and space-based telescopes to understand more about the galaxy and its past behavior.

The scientists discovered the galaxy had recently doubled in brightness in mid-infrared wavelengths, become four times brighter in the ultraviolet, and at least 10 times brighter in the X-ray range. What triggered the sudden brightening is unclear, but writing in Astronomy and Astrophysics, the researchers say the most likely explanation is the creation of an "active galactic nucleus" where a vast black hole at the centre of a galaxy starts actively consuming the material around it.

Active galactic nuclei emit a broad spectrum of light as gas around the black hole heats up and glows, and surrounding dust particles absorb some wavelengths and re-radiate others. But it is not the only possibility. The team has not ruled out an exotic form of "tidal disruption event," a highly restrained phrase to describe a star that is ripped apart after straying too close to a black hole. Tidal disruption events tend to be brief affairs, brightening a galaxy for no more than a few hundred days, but more measurements are needed to rule out the process.

Slashdot reader hackertourist shared this announcement from NASA's Jet Propulsion Laboratory: Edward C. Stone, former director of NASA's Jet Propulsion Laboratory and project scientist of the Voyager mission for 50 years, died on June 9, 2024. He was age 88...

Stone served on nine NASA missions as either principal investigator or a science instrument lead, and on five others as a co-investigator (a key science instrument team member). These roles primarily involved studying energetic ions from the Sun and cosmic rays from the galaxy. He had the distinction of being one of the few scientists involved with both the mission that has come closest to the Sun (NASA's Parker Solar Probe) and the one that has traveled farthest from it (Voyager).

Stone is best known for his work on NASA's longest-running mission, Voyager, whose twin spacecraft launched in 1977 and are still exploring deep space today. He served as Voyager's sole project scientist from 1972 until his retirement in 2022. Under Stone's leadership, the mission took advantage of a celestial alignment that occurs just once every 176 years to visit Jupiter, Saturn, Uranus, and Neptune. During their journeys, the spacecraft revealed the first active volcanoes beyond Earth, on Jupiter's moon Io, and an atmosphere rich with organic molecules on Saturn's moon Titan. Voyager 2 remains the only spacecraft to fly by Uranus and Neptune, revealing Uranus' unusual tipped magnetic poles, and the icy geysers erupting from Neptune's moon Triton.
The mission "transformed our understanding of the solar system, and is still providing useful data today," writes hackertourist. (Watch Stone speak in this 2018 video about the Voyager 2 spacecraft.) NASA's announcement also includes stories of Stone's desire to engage the public and his thoughtfulness in considering the true boundary of interstellar space. As director of JPL, Stone was responsible for more than two dozen other missions, including landing NASA's Pathfinder mission with the first Mars rover in 1996. "Ed Stone was a trailblazer who dared mighty things in space. He was a dear friend to all who knew him, and a cherished mentor to me personally," said Nicola Fox, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington.

"Ed took humanity on a planetary tour of our solar system and beyond, sending NASA where no spacecraft had gone before. His legacy has left a tremendous and profound impact on NASA, the scientific community, and the world."

The sun fired off a volley of radiation-riddled outbursts in May. When they slammed into Earth's magnetic bubble, the world was treated to iridescent displays of the northern and southern lights. But our planet wasn't the only one in the solar firing line. From a report: A few days after Earth's light show, another series of eruptions screamed out of the sun. This time, on May 20, Mars was blitzed by a beast of a storm. Observed from Mars, "this was the strongest solar energetic particle event we've seen to date," said Shannon Curry, the principal investigator of NASA's Mars Atmosphere and Volatile Evolution orbiter, or MAVEN, at the University of Colorado, Boulder.

When the barrage arrived, it set off an aurora that enveloped Mars from pole to pole in a shimmering glow. If they were standing on the Martian surface, "astronauts could see these auroras," Dr. Curry said. Based on scientific knowledge of atmospheric chemistry, she and other scientists say, observers on Mars would have seen a jade-green light show, although no color cameras picked it up on the surface. But it's very fortunate that no astronauts were there. Mars's thin atmosphere and the absence of a global magnetic shield meant that its surface, as registered by NASA's Curiosity rover, was showered by a radiation dose equivalent to 30 chest X-rays -- not a lethal dose, but certainly not pleasant to the human constitution.

The dream of perpetual, emissionless flight is getting closer to reality. Aviation giants, telecoms, investors, and military agencies are pouring millions into developing these prototypes, which could revolutionize aerial surveillance, emergency communications, and more.

Solar planes absorb energy via panels covering their wings and bodies, allowing them to fly indefinitely as long as the sun shines. Advances in battery technology now enable longer flights and overnight operation, albeit with less power than jet fuel. These slow, lightweight aircraft can fly at altitudes and durations impossible for humans, making them ideal for monitoring, telecom, and disaster response. Companies like BAE Systems, Airbus, and Skydweller are racing to commercialize solar planes, with hopes of offering services by 2026-2027. The unregulated stratosphere is a key focus, with planes acting as "steerable satellites." WSJ adds: Most of the companies trying to commercialize solar planes are building aircraft that are lightweight, autonomous and can fly at altitudes and for lengths of time that humans can't tolerate. Unlike balloons, solar planes are steerable, a big advantage for monitoring a target on the ground or providing telecom coverage without being blown off course. They are also cheaper and closer to Earth than satellites, putting them in a sweet spot for services that can't currently be offered by either, executives in charge of solar-aircraft projects say. The planes can capture higher resolution photos or video than satellites, or deliver broadband internet from the air, another thing satellites can't do.

"The first European Space Agency instrument to land on the Moon has detected the presence of negative ions on the lunar surface produced through interactions with the solar wind," according to a statement from the agency, collecting over three hours of data, "three times more than what the science teams needed for mission success..." The solar wind is a constant flow of radiation and particles from the Sun. Earth's magnetic field acts as a shield. In contrast, the Moon has no magnetic field and a very tenuous atmosphere, called the exosphere. When the solar wind hits the Moon,âthe surface reacts, kicking up secondary particles... While the positively charged particles have been measured from orbit before, measuring negative particles was a challenge. Negative ions are short-lived and cannot make it to orbit.
The instrument was dropped off by China's Chang'e-6 lunar lander, and Europe's ground stations are also providing support for that mission. Futurism reports: Within just over 48 hours, China's Chang'e-6 lunar touched down on the far side of the Moon, successfully scooped up samples, and kicked off once again. It was an extraordinary feat, representing the first-ever samples ever collected from the side of the Moon that permanently faces away from us. During its brief visit, the lander also dropped off several scientific payloads on the lunar service, including the European Space Agency's Negative Ions at the Lunar Surface instrument.
The lander also unfurled China's red and gold flag for the first time on the far side of the moon, according to the Associated Press. And then... Its ascender lifted off Tuesday morning at 7:38 a.m. Beijing time, with its engine burning for about six minutes as it entered a preset orbit around the moon, the China National Space Administration said. The agency said the spacecraft withstood a high temperature test on the lunar surface, and acquired the samples using both drilling and surface collection before stowing them in a container inside the ascender of the probe as planned. The container will be transferred to a reentry capsule that is due to return to Earth in the deserts of China's Inner Mongolia region about June 25.
The samples "could help researchers figure out why the moon's two sides are so starkly different," writes Science News: Spacecraft observations of the farside show very little volcanic activity. Some scientists suspect that this is because the nearside crust is much thinner, which would have allowed more magma to come up from below the surface, says Kerri Donaldson Hanna, a planetary geologist at the University of Central Florida in Orlando.

There is evidence that some volcanism occurred in the South Pole-Aitken basin and in Apollo crater, though it appears this activity happened roughly 3.5 billion years ago. It's possible the impact that created both Aiken and Apollo weakened the lunar crust, forming fractures and allowing magma to flow. The samples onboard Chang'e-6 could contain clues as to whether or not this happened.

Both Chinese and international researchers will be able to study the material. Donaldson Hanna is looking forward to seeing what insights will be gleaned from Chang'e-6 as well as future landers, such as those in NASA's Commercial Lunar Payload Services program.
Thanks to Slashdot reader cusco for sharing the news.

The 34-year-old Hubble Space Telescope is now operating with its final two working gyroscopes, necessitating a switch to a less productive "one-gyro" mode to extend its operational life. This contingency plan will reduce Hubble's productivity by over 12%, limit its ability to track fast-moving objects, and decrease the portion of the sky it can observe. That said, NASA expects it to keep functioning through 2035. Science.org reports: Normally, Hubble measures its location in space with a system that includes three gyroscopes -- rapidly spinning wheels that can sense forces in three directions. But in a 4 June press conference, NASA officials said one of the telescope's three remaining gyroscopes is on the fritz. The agency is now invoking a contingency plan: a "one-gyro" mode that keeps the other functioning gyroscope in reserve. The mode will reduce the telescope's productivity by more than 12% but preserve its ability to observe for years to come, Mark Clampin, NASA's astrophysics division director, said at the press conference. "We believe this is our best approach to support Hubble science through this decade and into the next."

Hubble's gyroscopes, which spin at 19,200 revolutions per minute, are extremely precise but finicky. The agency has flown a total of 22 gyroscopes across various servicing missions and is now down to the last two of the six currently onboard. In one-gyro mode, Hubble must rely on its less precise star trackers and other sensors to verify its position, a slower process that leads to reduced productivity. "It will take us more time to slew from one target attitude to the next, and to be able to lock on to that science target," said Patrick Crouse, Hubble's project manager at NASA's Goddard Space Flight Center.

A one-gyro Hubble will also struggle to track fast-moving targets, such as asteroids within the orbit of Mars, and to swivel to spot transient distant phenomena such as supernovae, according to a 2016 report (PDF) from the Space Telescope Science Institute, which operates Hubble. In addition, the inefficiencies of one-gyro mode will reduce the portion of the sky that Hubble can safely point to at any given moment, from 82% to roughly 40%, including a larger avoidance zone near the Sun. It won't be able to observe Venus or the Moon, nor will it be able to reliably spot comets when they're near the Sun. Its ability to scrutinize distant exoplanets will also be hampered, especially in gathering the spectral measurements used to discern alien atmospheres. Furthermore, a one-gyro Hubble won't be able to perform as many simultaneous observations with the new JWST space observatory. Moving forward, the two telescopes' fields of view at any given moment may overlap by less than 20%, according to a 2019 estimate anticipating this event from a Hubble advisory committee.