"NASA's Juno Jupiter probe has captured unprecedented views of the largest moon in the solar system," reports Space.com: During a close flyby of Jupiter on Dec. 26, 2019, Juno mapped the north polar regions of the icy satellite Ganymede in infrared light, something no other spacecraft had done before. The data, which Juno gathered using its Jovian Infrared Auroral Mapper (JIRAM) instrument, show that Ganymede's northern reaches are very different than locales closer to the equator of the moon, which is bigger than the planet Mercury. "The JIRAM data show the ice at and surrounding Ganymede's north pole has been modified by the precipitation of plasma," Alessandro Mura, a Juno co-investigator at the National Institute for Astrophysics in Rome, said in a statement.

"It is a phenomenon that we have been able to learn about for the first time with Juno because we are able to see the north pole in its entirety."

This plasma consists of charged particles from the sun, which have been trapped by Jupiter's powerful magnetic field. Unlike any other moon, the 3,274-mile-wide (5,269 kilometers) Ganymede has a magnetic field of its own, which funnels the plasma toward its poles. A similar phenomenon occurs here on Earth, which explains why the auroras occur at high latitudes on our planet. But Ganymede has no atmosphere to obstruct and be lit up by these particles, so they slam hard into the ice at and around both poles.
The article notes that the $1.1 billion Juno probe "launched in August 2011 and arrived at Jupiter in July 2016."

"A European and NASA spacecraft has snapped the closest pictures ever taken of the sun," reports the Associated Press, "revealing countless little 'campfires" flaring everywhere. Scientists on Thursday released the first images taken by Solar Orbiter, launched from Cape Canaveral in February. The orbiter was about 48 million miles from the sun — about halfway between Earth and the sun — when it took the stunning high-resolution pictures last month... European Space Agency project scientist Daniel Muller described the observed multitude of "campfires" shooting into the corona, or sun's crown-like outer atmosphere, as quite possibly "the tiny cousins of the solar flares that we already know." Millions if not billions of times smaller, these tiny flares may be heating the corona, he said, long known to be hundreds of times hotter than the actual solar surface for unknown reasons... These so-called campfires, Berghmans noted, are "literally everywhere we look." Not yet well understood, they could be mini explosions, or nanoflares. More measurements are planned.

The $1.5 billion spacecraft will tilt its orbit as the mission goes on, providing unprecedented views of the sun's poles. This vantage point will allow it to capture the first pictures of the solar poles.

IEEE Spectrum reports: There's still plenty that can disrupt radio communications... Rather than waiting for a human on Earth to tell the radio how to adapt its systems — during which the commands may have already become outdated — a radio with a neural network can do it on the fly. Such a device is called a cognitive radio. Its neural network autonomously senses the changes in its environment, adjusts its settings accordingly — and then, most important of all, learns from the experience... Worcester Polytechnic Institute and Penn State University, in cooperation with NASA, recently tested the first cognitive radios designed to operate in space and keep missions in contact with Earth. In our tests, even the most basic cognitive radios maintained a clear signal between the International Space Station (ISS) and the ground. We believe that with further research, more advanced, more capable cognitive radios can play an integral part in successful deep-space missions in the future, where there will be no margin for error...

Our own effort to create a proof-of-concept cognitive radio for space communications was possible only because of the state-of-the-art Space Communications and Navigation (SCaN) test bed on the ISS. NASA's Glenn Research Center created the SCaN test bed specifically to study the use of software-defined radios in space. The test bed was launched by the Japan Aerospace Exploration Agency and installed on the main lattice frame of the space station in July 2012... Ours would be the first-ever cognitive radio experiments conducted in space...

During the tests, the cognitive radio clearly showed that it could learn how to maintain a communications link. The radio autonomously selected settings to avoid losing contact, and the link remained stable even as the radio adjusted itself...

Overall, the success of our tests on the SCaN test bed demonstrated that cognitive radios could be used for deep-space missions.

"The U.S. wants to build nuclear power plants that will work on the moon and Mars, and on Friday put out a request for ideas from the private sector on how to do that," reports Time magazine: The U.S. Department of Energy put out the formal request to build what it calls a fission surface power system that could allow humans to live for long periods in harsh space environments.

The Idaho National Laboratory, a nuclear research facility in eastern Idaho, the Energy Department and NASA will evaluate the ideas for developing the reactor. The lab has been leading the way in the U.S. on advanced reactors, some of them micro reactors and others that can operate without water for cooling. Water-cooled nuclear reactors are the vast majority of reactors on Earth. "Small nuclear reactors can provide the power capability necessary for space exploration missions of interest to the Federal government," the Energy Department wrote in the notice published Friday...

The goal is to have a reactor, flight system and lander ready to go by the end of 2026... Officials say operating a nuclear reactor on the moon would be a first step to building a modified version to operate in the different conditions found on Mars.

"A photo and film restoration specialist, who goes by the name of DutchSteamMachine, has worked some AI magic to enhance original Apollo film, creating strikingly clear and vivid video clips and images," reports Universe Today: Take a look at this enhanced footage from an Apollo 16 lunar rover traverse with Charlie Duke and John Young, where the footage that was originally shot with 12 frames per second (FPS) has been increased to 60 FPS... And I was blown away by the crisp view of the Moon's surface in this enhanced view of Apollo 15's landing site at Hadley Rille... Or take a look at how clearly Neil Armstrong is visible in this enhanced version of the often-seen "first step" video from Apollo 11 taken by a 16mm video camera inside the Lunar Module...

The AI that DutchSteamMachine uses is called Depth-Aware video frame INterpolation, or DAIN for short. This AI is open source, free and constantly being developed and improved upon... "People have used the same AI programs to bring old film recordings from the 1900s back to life, in high definition and colour," he said. "This technique seemed like a great thing to apply to much newer footage...."

DutchSteamMachine does this work in his spare time, and posts it for free on his YouTube page. His tagline is "Preserving the past for the future..." And he's planning to keep it all coming. "I plan to improve tons of Apollo footage like this," he said. "A lot more space and history-related footage is going to be published on my YT channel continuously." He also has a Flickr page with more enhanced imagery. [And a Patreon page...]
Long-time Slashdot reader schwit1 calls it "similar to what Peter Jackson did with old World War I footage for They Shall Not Grow Old ."

"Comet Neowise has been the brightest and most visible space snowball in a generation, but it's also the first naked-eye comet to visit us in the new era of satellite mega-constellations like SpaceX's Starlink," writes CNET.

"In just the latest episode of Starlink 'trains' irritating astronomers, a number of images have been circulating of the satellites photo-bombing Comet Neowise glamour shots..."

Live Science explains: Visible just above the horizon right now, the comet appears faint and small to the naked eye, but can be seen clearly through cameras with long, telephoto lenses. Usually, when photographers capture objects like this in the night sky they use long exposure times, leaving the camera aperture open to collect light over the course of several seconds. But now comet-chasers report that a new fleet of SpaceX's Starlink satellites is leaving bright smears across their NEOWISE snaps, as the shiny orbiters streak through their frames during long exposures.

Long-time Slashdot reader schwit1 shared this article from HealthDay: In earlier studies, patients have pegged CPR survival rates at between 19% and 75%. But the real rate of survival is about 12% for cardiac arrests that occur outside hospitals and between 24% and 40% for those that happen in the hospital, according to the report published online July 13 in the Emergency Medicine Journal.

For the new study, Bandolin's team surveyed 500 emergency department patients and their companions. Fifty-three percent said they had done or witnessed CPR, and 64% had taken a CPR course. Ninety-five percent said their main source of CPR information was television. About half said the success rate of CPR topped 75%. And nine out of 10 said they wanted to receive CPR if it was needed.

But only 28% had discussed CPR with a doctor, the investigators noted in a journal news release.

"Researchers have spotted large waves of martian sand migrating for the first time," reports Science magazine.

"The discovery dispels the long-held belief that these 'megaripples' haven't moved since they formed hundreds of thousands of years ago. They're also evidence of stronger-than-expected winds on the Red Planet." It's pretty staggering that humans can detect these changes on Mars, says Ralph Lorenz, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory who was not involved in the research. "We can now measure processes on the surface of another planet that are just a couple times faster than our hair grows...."

Since the early 2000s, Mars rovers and orbiters have repeatedly spotted megaripples on the Red Planet. But they didn't seem to change in any measurable way, which led some scientists to think they were relics from Mars's past, when its thicker atmosphere permitted stronger winds. Now, using images captured by NASA's Mars Reconnaissance Orbiter, Simone Silvestro, a planetary scientist at Italy's National Institute of Astrophysics in Naples, and his colleagues have shown that some megaripples do creep along — just very slowly. The researchers focused on two sites near the equator of Mars... Megaripples in both regions advanced by about 10 centimeters per year, the team reports in the Journal of Geophysical Research: Planets...

It's a surprise that megaripples move at all on Mars, says Jim Zimbelman, a planetary geologist at the Smithsonian Institution's Air and Space Museum. Just a few decades ago, there was no evidence that sands on Mars were mobile, he says. "None of us thought that the winds were strong enough...." Atmospheric models of Mars suggest winds capable of moving sand are rare. This discovery of migrating megaripples will force those models to be revised, the team suggests....

Megaripples on the move are beacons of windy conditions, which might in turn kick-start dust storms, the researchers suggest. Airborne dust can blanket solar panels, reducing their efficiency, and it can also gum up mechanical parts like gears. That's bad news for Mars rovers and human habitats alike.

When asked for the most efficient way to sort a million 32-bit integers in 2008, then-presidential candidate Barack Obama answered, "I think the bubble sort would be the wrong way to go."

But people are still searching for the best possible sorting algorithms, explains Slashdot reader scandum: Long has the conviction been held that quicksort is faster than merge sort. Timsort (derived from merge sort and insertion sort) was introduced in 2002 and while slower than quicksort for random data, Timsort performs better on ordered data.

Quadsort (derived from merge sort) was introduced in 2020 and is faster than quicksort for random data, and slightly faster than Timsort on ordered data.

Also of notice is the significant performance difference on small arrays, quadsort is on average two times faster than Timsort on data sets between 10 and 1000 elements. Quadsort achieves this performance through several optimizations spread out over 1500 lines of code that get the maximum performance out of merge sort.
Quadsort's GitHub page explains: After the first round of sorting a single if check determines if the four swap variables are sorted in order, if that's the case the swap finishes up immediately. Next it checks if the swap variables are sorted in reverse-order, if that's the case the sort finishes up immediately. If both checks fail...two checks remain to determine the final order.

The New York Times has created a surprising interactive analysis of the number of coronavirus cases (per million residents) in different countries: With its cases surging since mid-June, the United States is squarely in the top 10. Leading the outbreak now are countries in the Persian Gulf, where the virus has spread rapidly among foreign laborers. [Oman, Bahrain, and Kuwait.] Rounding out the top 10 are South Africa, Israel and several countries in Latin America. [Panama, Brazil, Colombia, Bolivia]

The current U.S. outbreak is especially stark when compared to other large, high-income countries. All have few cases today compared to the United States... Italy and Spain saw some of the worst early outbreaks, before strict control measures brought cases down. Now, some schools are open, adults are back at work and tourists are on vacation. Even Sweden, where cases surged after the government chose to forgo the strict lockdowns of its neighbors, has seen cases drop.

The surge in the United States is so extreme that, once adjusted for population, these 10 states are recording more new cases than any country in the world. [Florida, Louisiana, Mississippi, Nevada, Arizona, Alabama, South Carolina, Texas, Idaho, and Tennessee].

An anonymous reader shares a report: The anecdotes are alarming. A woman in Los Angeles seemed to recover from Covid-19, but weeks later took a turn for the worse and tested positive again. A New Jersey doctor claimed several patients healed from one bout only to become reinfected with the coronavirus. And another doctor said a second round of illness was a reality for some people, and was much more severe. These recent accounts tap into people's deepest anxieties that they are destined to succumb to Covid-19 over and over, feeling progressively sicker, and will never emerge from this nightmarish pandemic. And these stories fuel fears that we won't be able to reach herd immunity -- the ultimate destination where the virus can no longer find enough victims to pose a deadly threat.

But the anecdotes are just that -- stories without evidence of reinfections, according to nearly a dozen experts who study viruses. "I haven't heard of a case where it's been truly unambiguously demonstrated," said Marc Lipsitch, an epidemiologist at the Harvard T.H. Chan School of Public Health. Other experts were even more reassuring. While little is definitively known about the coronavirus, just seven months into the pandemic, the new virus is behaving like most others, they said, lending credence to the belief that herd immunity can be achieved with a vaccine. It may be possible for the coronavirus to strike the same person twice, but it's highly unlikely that it would do so in such a short window or to make people sicker the second time, they said. What's more likely is that some people have a drawn-out course of infection, with the virus taking a slow toll weeks to months after their initial exposure. People infected with the coronavirus typically produce immune molecules called antibodies. Several teams have recently reported that the levels of these antibodies decline in two to three months, causing some consternation. But a drop in antibodies is perfectly normal after an acute infection subsides, said Dr. Michael Mina, an immunologist at Harvard University.

NASA has announced that the often delayed James Webb space telescope (JWST) is to be delayed once more. Instead of a launch on 30 March 2021, the mission has now slipped to 31 October 2021. From a report: The seven-month delay is the result of impacts from the coronavirus pandemic, as well as technical challenges. The spacecraft is currently being tested at Northrop Grumman, NASA's main industrial partner on the mission, in Redondo Beach, California. A recently completed risk assessment exercise recommended the delay. Once ready, JWST will be transported to Europe's spaceport in Kourou, French Guiana, where it will be launched by the European Space Agency on an Ariane 5 ECA rocket. Touted as the successor to the Hubble space telescope, JWST has had a troubled development characterised by major cost overruns and delays. Development work started in the late 1990s, with a launch date set for 2007.

AmiMoJo shares a report from the BBC: China has launched its first rover mission to Mars. The six-wheeled robot, encapsulated in a protective probe, was lifted off Earth by a Long March 5 rocket from the Wenchang spaceport on Hainan Island at 12:40 local time (04:40 GMT). It should arrive in orbit around the Red Planet in February. Called Tianwen-1, or "Questions to Heaven," the rover won't actually try to land on the surface for a further two to three months. This wait-and-see strategy was used successfully by the American Viking landers in the 1970s. It will allow engineers to assess the atmospheric conditions on Mars before attempting what will be a hazardous descent. Tianwen-1 is one of three missions setting off to Mars in the space of 11 days. On Monday, the United Arab Emirates (UAE) launched its Hope satellite towards the Red Planet. And in a week from now, the U.S. space agency (Nasa) aims to despatch its next-generation rover, Perseverance.

AleRunner writes: The United States on Tuesday recorded more than 1,000 daily deaths from COVID-19 for the first time since May, according to Politico. This trend continued and actually increased on Wednesday with over 1,200 deaths. Whilst there have been suggestions that the increase in cases in the US was an artifact of greater testing, the new data on deaths makes it starkly clear that these suggestions were wrong and that cases are increasing at a greater rate than testing, meaning that the official death rate is going to continue increasing for some time. Even these shocking numbers are likely an underestimate with reputable researchers having shown that many COVID-19 deaths have been registered under other causes. More than half a million people worldwide are dead and 15 million are infected, however the U.S. remains world leader in coronavirus cases with Brazil still far behind in second place.

The UK and US have accused Russia of launching a weapon-like projectile from a satellite in space. Joe2020 shares a report: In a statement, the head of the UK's space directorate said: "We are concerned by the manner in which Russia tested one of its satellites by launching a projectile with the characteristics of a weapon." The statement said actions like this "threaten the peaceful use of space." The US has previously raised concerns about this Russian satellite. In his statement, Air Vice Marshal Harvey Smyth, head of the UK's space directorate, said: "Actions like this threaten the peaceful use of space and risk causing debris that could pose a threat to satellites and the space systems on which the world depends. We call on Russia to avoid any further such testing. We also urge Russia to continue to work constructively with the UK and other partners to encourage responsible behaviour in space."

In a new report on Science Advances, Minwoo Choi and a team of scientists in Electronic Engineering and Materials Science in the Republic of Korea, developed a wearable, full-colour OLED display using a two-dimensional (2-D) material-based backplane transistor. Phys.Org reports: They engineered an 18-by-18 thin-film transistor array on a thin molybdenum disulfide (MoS2) film and transferred it to an aluminium oxide (Al2O3)/polyethylene terephthalate (PET) surface. Choi et al. then deposited red, green and blue OLED pixels on the device surface and observed excellent mechanical and electrical properties of the 2-D material. The surface could drive circuits to control the OLED pixels to form an ultrathin, wearable device.

In this work, Choi et al. developed a large-area MoS2 TFT array to operate 324 pixels in a 2-inch RGB OLED, in which the full-color display demonstrated an active-matrix configuration. The RGB OLEDs were made of different optoelectronic characteristics, therefore the team designed the backplane TFTs to control each color pixel. The experimental setup was promising as a wearable display and functioned steadily on human skin without adverse effects. The team used heterogenous material designs to form optoelectronics in the present work. [...] The low stiffness of the ultrathin device prevented the deterioration of optical and electrical properties during substantial mechanical deformation reflexes -- after its transfer to a human hand. Based on the current-voltage characteristics (I-V), the current level did not change during skin shrinkage or skin stretching exercises and the on-state also did not fluctuate during active-matrix display operation. While the device stability is still in development, the team aim to conduct further engineering to improve the MoS2 film for practical applications as a wearable, full-color AMOLED display.

A reader shares a report from Live Science: After five years of peering into the deepest reaches of space, researchers have released what they call the "largest three-dimensional map of the universe" ever. No, you cannot see your house. The mind-boggling map is the result of an ongoing project called the Sloan Digital Sky Survey (SDSS) -- an ambitious, international quest to map the expansion of the observable universe, and hopefully solve a few cosmic conundrums in the process. With this newest update, the project has mapped and measured more than 2 million galaxies, stretching from our Milky Way to ancient objects more than 11 billion light-years away.

The detailed new map will help astronomers piece together a murky period of the universe's expansion known as "the gap." The gap begins a few billion years after the Big Bang. Scientists are able to measure the rate of the universe's expansion before this thanks to the cosmic microwave background -- ancient radiation left over from the infancy of the universe that researchers can still detect; and they can calculate recent expansion by measuring how the distance between Earth and nearby galaxies increases over time. But expansion in the middle period has been little studied because the light of galaxies more than a few hundred million light-years away can be incredibly faint. To fill in the gap, a team of more than 100 scientists from around the world looked at not just distant galaxies, but also bright-burning quasars (extremely luminous objects powered by the hungriest black holes in the cosmos). The astronomers described their findings in 23 new studies released on July 20. The press release from the Sloan Digital Sky Survey (SDSS) can be viewed here.

An anonymous reader quotes a report from Scientific American: For years scientists have sought to create the ultimate cancer-screening test -- one that can reliably detect a malignancy early, before tumor cells spread and when treatments are more effective. A new method reported today in Nature Communications brings researchers a step closer to that goal. By using a blood test, the international team was able to diagnose cancer long before symptoms appeared in nearly all the people it tested who went on to develop cancer. [...] Kun Zhang, a bioengineer at the University of California, San Diego, and a co-author of the study, and his colleagues began collecting samples from people before they had any signs that they had cancer. In 2007 the researchers began recruiting more than 123,000 healthy individuals in Taizhou, China, to undergo annual health checks -- an effort that required building a specialized warehouse to store the more than 1.6 million samples they eventually accrued. Around 1,000 participants developed cancer over the next 10 years.

Zhang and his colleagues focused on developing a test for five of the most common types of cancer: stomach, esophageal, colorectal, lung and liver malignancies. The test they developed, called PanSeer, detects methylation patterns in which a chemical group is added to DNA to alter genetic activity. Past studies have shown that abnormal methylation can signal various types of cancer, including pancreatic and colon cancer. The PanSeer test works by isolating DNA from a blood sample and measuring DNA methylation at 500 locations previously identified as having the greatest chance of signaling the presence of cancer. A machine-learning algorithm compiles the findings into a single score that indicates a person's likelihood of having the disease. The researchers tested blood samples from 191 participants who eventually developed cancer, paired with the same number of matching healthy individuals. They were able to detect cancer up to four years before symptoms appeared with roughly 90 percent accuracy and a 5 percent false-positive rate.

Scott K. Johnson writes via Ars Technica: One of the most important numbers in climate science is 3C. This isn't about a projection of future warming or the impacts that come with it, though. It's about how much warming you get if you double the amount of greenhouse gasses in the atmosphere. That value can be made more general as a metric known as "climate sensitivity," which describes how much warming you get for a given amount of emissions. If the number is small, we can burn a lot of fossil fuels with minimal consequences. If the number is extremely high, emissions are extraordinarily dangerous. This number is commonly defined against a doubling of the concentration of CO2 in the air, in part because CO2's effect is logarithmic and each doubling is roughly equivalent. Calculations of this value go back to the turn of the 20th century, when the Swedish scientist Svante Arrhenius came up with numbers in the 4-6C range. But a major milestone was reached in 1979, when a group of scientists released a climate report that included this value. The scientists wrote, "We estimate the most probable global warming for a doubling of CO2 to be near 3C with a probable error of +/-1.5C."

Despite all the scientific progress since then, that answer (1.5-4.5ÂC) has held up. The 2007 Intergovernmental Panel on Climate Change report tightened it up a bit to 2.0-4.5C, but then a handful of studies released just before their 2013 report caused confusion that led to a return to the old 1.5-4.5C range. Shrinking that range has been a goal of climate scientists, though the problem has proved stubborn. In a notable step forward, a group of 25 climate scientists published a study this week that presents a new synthesis of the evidence. And they conclude that a narrower range is warranted.

An anonymous reader quotes a report from Bloomberg: Scores of Russia's business and political elite have been given early access to an experimental vaccine against Covid-19, according to people familiar with the effort, as the country races to be among the first to develop an inoculation. Top executives at companies including aluminum giant United Co. Rusal, as well as billionaire tycoons and government officials began getting shots developed by the state-run Gamaleya Institute in Moscow as early as April, the people said. They declined to be identified as the information isn't public.

Kremlin spokesman Dmitry Peskov, who recovered from Covid-19 after being hospitalized with the virus in May, said he doesn't know the names of anyone who's received the institute's vaccine. Peskov's comments followed a Health Ministry statement that said only participants in Gamaleya's trials are currently eligible for the jabs. While the new shots are "safe" because they're based on proven vaccines for other diseases, their effectiveness has yet to be determined, according to Sergei Netesov, a former executive at Vector, a state-run virology center in Novosibirsk, Siberia, that's also working on an inoculation. "Those who take it do so at their own risk," Netesov said.