United States

A Case Against Making Daylight Saving Time Permanent: We've Tried this Before and It Didn't Go Over Well (washingtonpost.com) 256

Aaron Blake, writing at The Washington Post: Americans turned their clocks forward an hour earlier this week for what some hope will be the last time, as bipartisan momentum builds for making daylight saving time permanent. As The Post's Capital Weather Gang notes, a bill spearheaded by Sen. Marco Rubio (R-Fla.) has united lawmakers from opposite parties who can't agree on much of anything these days. It also builds upon legislation already passed in 16 states -- both red and blue -- and current debates in states such as Nevada. All of it reflects apparently real momentum behind the effort. But as most of us bemoan our messed-up sleep schedules on the first Monday after losing an hour, it's worth a little history lesson: We've tried this before, and it didn't go over well. Whatever momentary mental anguish you're experiencing right now, there are huge trade-offs that many or most Americans have previously decided aren't worth the switch.

The year was 1973, and the United States was experiencing an energy crisis. Among the proposals put forward by President Richard M. Nixon in a November address was making daylight saving time permanent for the next two winters. Despite scant evidence of daylight saving time's past benefit on the energy supply (dating back to DST's various introductions since World War I), Americans really liked the idea. Polling in November and December 1973 showed strong and in some cases overwhelming support -- 57 percent in a Gallup poll, 74 percent in a Louis Harris and Associates poll, and 73 percent in a poll from the Roper Organization. The policy was quickly implemented in early January 1974. But it just as quickly fell out of favor. In a Roper poll conducted in February and March, just 30 percent remained in favor of year-round daylight saving time, while a majority favored switching times again. Louis Harris polling in March showed just 19 percent of people said it had been a good idea, while about twice as many -- 43 percent -- said it was a bad one.

A big reason for the about-face? Whatever benefits might have been gleaned by giving people more sunlight in the evening during the winter, it also meant longer, darker mornings. Parents were suddenly sending their kids to school in the cold and the dark for months on end. As the Capital Weather Gang noted, such a change means the sun wouldn't rise before 8 a.m. in Washington for more than two and a half months, between late November and mid-February. The morning darkness would linger even longer farther north. Polling later that year -- after the dark mornings had waned -- was more mixed, with an Opinion Research poll in September showing 31 percent of people strongly favored the idea and 42 percent strongly opposed it. But even that wasn't good. And the idea was abandoned shortly before the next round of morning darkness would descend in the winter of 1974-1975. A Department of Transportation study at the time concluded that the change actually had minimal impact on saving energy and might have actually increased gasoline consumption.

Space

Astronomer Makes Navigation System For Interstellar Space Travel (sciencealert.com) 68

rushtobugment shares a report from ScienceAlert: Using the positions and shifting light of stars, both near and far, astronomer Coryn A.L. Bailer-Jones has demonstrated the feasibility of autonomous, on-the-fly navigation for spacecraft traveling far beyond the Solar System. "When traveling to the nearest stars, signals will be far too weak and light travel times will be of order years," Bailer-Jones wrote in his paper, which is currently available on the preprint server arXiv, where it awaits peer review from the astronomy community. "An interstellar spacecraft will therefore have to navigate autonomously, and use this information to decide when to make course corrections or to switch on instruments. Such a spacecraft needs to be able to determine its position and velocity using only onboard measurements."

With a catalog of stars, Bailer-Jones was able to show that it's possible to work out a spacecraft's coordinates in six dimensions -- three in space and three in velocity -- to a high accuracy, based on the way the positions of those stars changes from the spacecraft's point of view. "As a spacecraft moves away from the Sun, the observed positions and velocities of the stars will change relative to those in a Earth-based catalog due to parallax, aberration, and the Doppler effect," he wrote. "By measuring just the angular distances between pairs of stars, and comparing these to the catalog, we can infer the coordinates of the spacecraft via an iterative forward-modeling process."

Bailer-Jones tested his system using a simulated star catalog, and then on nearby stars from the Hipparcos catalog compiled in 1997, at relativistic spacecraft speeds. Although this is not as accurate as Gaia, that's not terribly important - the aim was to test that the navigation system can work. With just 20 stars, the system can determine the position and velocity of a spacecraft to within 3 astronomical units and 2 kilometers per second (1.24 miles per second). This accuracy can be improved inverse to the square root of the number of stars; with 100 stars, the accuracy came down to 1.3 astronomical units and 0.7 kilometers per second. [...] The system hasn't taken stellar binaries into consideration, nor has it considered the instrumentation. The aim was to show that it could be done, as a first step towards actualizing it. It's even possible that it could be used in tandem with pulsar navigation so that the two systems might be able to minimize each other's flaws.

Space

The Myth of the Mutiny in Space (bbc.com) 9

It's been almost half a century since the three astronauts on board the Skylab 4 space mission famously fell out with mission control. Soon afterwards, reports began to circulate that they went on strike. But Ed Gibson, the only one of the crew still alive, says the idea that they stopped work is a myth. From a report: Bill Pogue got sick soon after the three astronauts arrived at the space station. It came as a surprise because Bill had been nicknamed "Iron Belly" during training at the Johnson Space Center in Houston, Texas. He could endlessly tolerate sitting in a rapidly rotating chair while moving his head backwards and forwards and side to side, without being sick. But this was the first time the three men had been in space and evidently resistance to motion sickness back on Earth didn't mean much up there.

Commander Jerry Carr suggested Bill eat a can of tomatoes to settle his stomach. Ed Gibson was sitting between the two men, and remembers the can floating past from left to right before his eyes. "Then I remember some bad noises coming from Bill, and a barf bag floating back from right to left," he says. "We felt discouraged because we knew we had so much work to do -- that's when we made our first mistake." Ed is 84 now and the Skylab 4 mission began in November 1973 but time hasn't dulled his most vivid memories -- the Earth from space, the blazing corona of the sun and the silence of a spacewalk. He's the last one of the astronauts able to share the story, because Jerry Carr and Bill Pogue have both died -- Carr last summer and Pogue in 2014. The Skylab space station was a research platform in orbit where astronauts helped scientists to study the human body's response to space flight, carried out experiments and made observations of the Sun and Earth. Skylab 4 was the final mission and as a result it had a long list of tasks to fulfil. The 84-day mission -- the longest ever at that point -- was on a tight schedule. Nasa was very concerned about someone getting sick, which would have meant losing precious time.

Nasa accepts that mission planners had not given the crew the typical period of adjustment to acclimatise to working weightlessly in orbit and had packed their schedules with large amounts of work. The number of spacewalks was also doubled, to four, to observe a newly discovered comet, Kohoutek. So the astronauts were already under pressure when they made their first bad decision. "We wanted to get organised before starting a big flurry with the ground so we decided to delay telling them about Bill being sick," says Ed. But they had forgotten that everything they said on board was being recorded, and that mission control was listening in. It wasn't long before the voice of Astronaut Office chief Alan Shepard came crackling over the radio from down in mission control, an exchange also broadcast to the public. "He got on the line and read us the riot act for not telling them immediately," says Ed. "Al was OK, we just didn't like being chewed out in front of the whole world."

Space

Scientists Believe 'Oumuamua Was Chunk of Extrasolar Pluto-Like Planet (phys.org) 66

lazarus shares a report from Phys.org: Two Arizona State University astrophysicists, Steven Desch and Alan Jackson of the School of Earth and Space Exploration, set out to explain the odd features of 'Oumuamua and have determined that it is likely a piece of a Pluto-like planet from another solar system. Desch and Jackson hypothesized that the object was made of different ices and calculated how quickly these ices would sublimate (passing from a solid to a gas) as 'Oumuamua passed by the sun. From there, they calculated the rocket effect, the object's mass and shape, and the reflectivity of the ices.

The scientists found one ice in particular -- solid nitrogen -- that provided an exact match to all the object's features simultaneously. And since solid nitrogen ice can be seen on the surface of Pluto, it is possible that a comet-like object could be made of the same material. "We knew we had hit on the right idea when we completed the calculation for what albedo (how reflective the body is) would make the motion of 'Oumuamua match the observations," said Jackson, who is a research scientist and an Exploration Fellow at ASU. "That value came out as being the same as we observe on the surface of Pluto or Triton, bodies covered in nitrogen ice."

They then calculated the rate at which chunks of solid nitrogen ice would have been knocked off the surfaces of Pluto and similar bodies early in our solar system's history. And they calculated the probability that chunks of solid nitrogen ice from other solar systems would reach ours. "It was likely knocked off the surface by an impact about half a billion years ago and thrown out of its parent system," Jackson said. "Being made of frozen nitrogen also explains the unusual shape of 'Oumuamua. As the outer layers of nitrogen ice evaporated, the shape of the body would have become progressively more flattened, just like a bar of soap does as the outer layers get rubbed off through use."

Space

Universe's Oldest Known Quasar Discovered 13 Billion Light-Years Away 38

Astronomers have found the farthest known source of radio emissions in the universe: a quasar 13 billion light-years from Earth spewing jets of particles at nearly the speed of light. Live Science reports: Quasars are some of the oldest, most distant, most massive and brightest objects in the universe. They make up the cores of galaxies where a rapidly spinning supermassive black hole gorges on all the matter that's unable to escape its gravitational grasp. While the black hole is devouring this matter, it's also blasting out an enormous amount of radiation that collectively can be more than a trillion times more luminous than the brightest stars, making quasars the brightest objects in the observable universe.

This quasar in particular, named P172+18, is a relic from around 780 million years after the Big Bang and reveals clues about one of the earliest ages of the universe -- the epoch of reionization. At the start of this period, the universe was darkly veiled by a mostly uniform cloud of hydrogen gas. Scientists refer to this time as the universe's dark ages, because most light emitted was quickly absorbed by the neutrally charged gas. Eventually, gravity collapsed the primordial gas into the first stars and quasars, which began to heat and ionize the surrounding gases, allowing light to pass through. [...] Further observations from telescopes [...] showed that P172+18 is nearly 300 million times more massive than the sun and is among the fastest-growing quasars ever discovered. The problem is, scientists don't know how a black hole became so massive this early on in the universe. The radio jets could be an explanation.
The researchers' findings will be published in The Astrophysical Journal.
Power

Saudi Arabia's Bold Plan To Rule the $700 Billion Hydrogen Market (bloomberg.com) 70

The kingdom is building a $5 billion plant to make green fuel for export and lessen the country's dependence on petrodollars. From a report: Sun-scorched expanses and steady Red Sea breezes make the northwest tip of Saudi Arabia prime real estate for what the kingdom hopes will become a global hub for green hydrogen. As governments and industries seek less-polluting alternatives to hydrocarbons, the world's biggest crude exporter doesn't want to cede the burgeoning hydrogen business to China, Europe or Australia and lose a potentially massive source of income. So it's building a $5 billion plant powered entirely by sun and wind that will be among the world's biggest green hydrogen makers when it opens in the planned megacity of Neom in 2025. The task of turning a patch of desert the size of Belgium into a metropolis powered by renewable energy falls to Peter Terium, the former chief executive officer of RWE AG, Germany's biggest utility, and clean-energy spinoff Innogy SE. His performance will help determine whether a country dependent on petrodollars can transition into a supplier of non-polluting fuels.

"There's nothing I've ever seen or heard of this dimension or challenge," Terium said. "I've been spending the last two years wrapping my mind around 'from scratch,' and now we're very much in execution mode." Hydrogen is morphing from a niche power source -- used in zeppelins, rockets and nuclear weapons == into big business, with the European Union alone committing $500 billion to scale up its infrastructure. Huge obstacles remain to the gas becoming a major part of the energy transition, and skeptics point to Saudi Arabia's weak track record so far capitalizing on what should be a competitive edge in the renewables business, especially solar, where there are many plans but few operational projects. But countries are jostling for position in a future global market, and hydrogen experts list the kingdom as one to watch.

The U.K. is hosting 10 projects to heat buildings with the gas, China is deploying fuel-cell buses and commercial vehicles, and Japan is planning to use the gas in steelmaking. U.S. presidential climate envoy John Kerry urged the domestic oil and gas industry to embrace hydrogen's "huge opportunities." That should mean plenty of potential customers for the plant called Helios Green Fuels. Saudi Arabia is setting its sights on becoming the world's largest supplier of hydrogen -- a market that BloombergNEF estimates could be worth as much as $700 billion by 2050. "You're seeing a more diversified portfolio of energy exports that is more resilient," said Shihab Elborai, a Dubai-based partner at consultant Strategy&. "It's diversified against any uncertainties in the rate and timing of the energy transition." Blueprints are being drawn and strategies are being announced, but it's still early days for the industry. Hydrogen is expensive to make without expelling greenhouse gases, difficult to store and highly combustible. Green hydrogen is produced by using renewable energy rather than fossil fuels. The current cost of producing a kilogram is a little under $5, according to the International Renewable Energy Agency.

Earth

Most Life on Earth Will Be Killed by Lack of Oxygen in a Billion Years (newscientist.com) 165

One billion years from now, Earth's atmosphere will contain very little oxygen, making it uninhabitable for complex aerobic life. From a report: Today, oxygen makes up around 21 per cent of Earth's atmosphere. Its oxygen-rich nature is ideal for large and complex organisms, like humans, that require the gas to survive. But early in Earth's history, oxygen levels were much lower -- and they are likely to be low again in the distant future. Kazumi Ozaki at Toho University in Funabashi, Japan, and Chris Reinhard at the Georgia Institute of Technology in Atlanta modelled Earth's climatic, biological and geological systems to predict how atmospheric conditions on Earth will change. The researchers say that Earth's atmosphere will maintain high levels of oxygen for the next billion years before dramatically returning to low levels reminiscent of those that existed prior to what is known as the Great Oxidation Event of about 2.4 billion years ago. "We find that the Earth's oxygenated atmosphere will not be a permanent feature," says Ozaki. One central reason for the shift is that, as our sun ages, it will become hotter and release more energy.

The researchers calculate that this will lead to a decrease in the amount of carbon dioxide in the atmosphere as CO2 absorbs heat and then breaks down. Ozaki and Reinhard estimate that in a billion years, carbon dioxide levels will become so low that photosynthesising organisms -- including plants -- will be unable to survive and produce oxygen. The mass extinction of these photosynthetic organisms will be the primary cause of the huge reduction in oxygen. "The drop in oxygen is very, very extreme -- we're talking around a million times less oxygen than there is today," says Reinhard.

Space

Space Hurricane Seen Above Magnetic North Pole Was Raining Electrons (businessinsider.com) 42

The first space hurricane ever was spotted in August 2014, consisting of "an eddy of plasma, a type of superhot, charged gas found throughout the solar system," reports Business Insider. "And instead of rain, this storm brought showers of electrons." From the report: In August 2014, satellites observed a swirling mass with a quiet center more than 125 miles above the North Pole. The space hurricane was more than 620 miles wide and high in the sky -- it formed in the ionosphere, between 50 and 600 miles up. Lockwood and his coauthors used the satellite data to create a 3D model of the storm. The space hurricane lasted eight hours, swirling counterclockwise. The researchers said it had several spiral arms snaking out from its center, a bit like a spiral galaxy. By plugging the satellite data into a computer model, Lockwood and his collaborators were able to reproduce the storm and figure out what caused it. They found that charged particles emitted by the sun's upper atmosphere, the corona, were to blame.

This steady stream of solar particles and coronal plasma is known as solar wind. It moves at about 1 million miles an hour. As solar wind reaches Earth, it encounters the planet's magnetic field. Earth has such a field because of the swirling liquid iron and nickel in its outer core, which gives rise to electric currents. The magnetosphere protects the planet from deadly radiation from the sun but also retains a tiny layer of plasma from that solar wind. Typically, solar winds glance off this protective sheath. But sometimes the incoming charged particles and plasma interact with either the trapped plasma or the electrical currents generating the field. Such interactions create disturbances in the magnetosphere. The 2014 space hurricane was one such disturbance.

Usually, magnetic fields don't mix. But if they do come close, portions of the fields can get realigned and even merge, forming a new pattern of magnetic energy. That's what likely happened on the day of the space storm: An influx of solar wind energy formed a new pattern above Earth's magnetic north pole. The storm acted as a channel from space into Earth's atmosphere, funneling some electrons down past the planet's armor. This particle rain could have wreaked havoc on our high-frequency radio communications, radar-detection systems, or satellite technology, the study's authors said. That's because charged solar particles that seep through Earth's magnetic field can cause malfunctions in computers and circuitry on satellites and the International Space Station. Luckily, in this case, no issues were observed.

Science

Asteroid Dust Found in Crater Closes Case of Dinosaur Extinction (phys.org) 56

Phys.org shares an announcement from the University of Texas at Austin: Researchers believe they have closed the case of what killed the dinosaurs, definitively linking their extinction with an asteroid that slammed into Earth 66 million years ago by finding a key piece of evidence: asteroid dust inside the impact crater.

Death by asteroid rather than by a series of volcanic eruptions or some other global calamity has been the leading hypothesis since the 1980s, when scientists found asteroid dust in the geologic layer that marks the extinction of the dinosaurs. This discovery painted an apocalyptic picture of dust from the vaporized asteroid and rocks from impact circling the planet, blocking out the sun and bringing about mass death through a dark, sustained global winter — all before drifting back to Earth to form the layer enriched in asteroid material that's visible today. In the 1990s, the connection was strengthened with the discovery of a 125-mile-wide Chicxulub impact crater beneath the Gulf of Mexico that is the same age as the rock layer.

The new study seals the deal, researchers said, by finding asteroid dust with a matching chemical fingerprint within that crater at the precise geological location that marks the time of the extinction... The telltale sign of asteroid dust is the element iridium — which is rare in the Earth's crust, but present at elevated levels in certain types of asteroids... In the crater, the sediment layer deposited in the days to years after the strike is so thick that scientists were able to precisely date the dust to a mere two decades after impact.

"We are now at the level of coincidence that geologically doesn't happen without causation," said co-author Sean Gulick, a research professor at the UT Jackson School of Geosciences who co-led the 2016 expedition with Joanna Morgan of Imperial College London...

The dust is all that remains of the 7-mile-wide asteroid that slammed into the planet millions of years ago, triggering the extinction of 75% of life on Earth, including all nonavian dinosaurs.

Space

The Dream of Sending a Submarine Through the Methane Seas of Saturn's Moon Titan (nytimes.com) 51

"Mars, Shmars; this voyager is looking forward to a submarine ride under the icebergs on Saturn's strange moon," says the New York Times, introducing a piece by cosmic affairs correspondent Dennis Overbye: What could be more exciting than flying a helicopter over the deserts of Mars? How about playing Captain Nemo on Saturn's large, foggy moon Titan — plumbing the depths of a methane ocean, dodging hydrocarbon icebergs and exploring an ancient, frigid shoreline of organic goo a billion miles from the sun? Those are the visions that danced through my head recently...diverted to the farther reaches of the solar system by the news that Kraken Mare, an ocean of methane on Titan, had recently been gauged for depth and probably went at least 1,000 feet down. That is as deep as nuclear submarines will admit to going. The news rekindled my dreams of what I think would be the most romantic of space missions: a voyage on, and ultimately even under, the oceans of Titan...

NASA recently announced that it would launch a drone called Dragonfly to the Saturnian moon in 2026. Proposals have also circulated for an orbiter, a floating probe that could splash down in a lake, even a robotic submarine. "The Titan submarine is still going," said Dr. Valerio Poggiali, research associate at the Cornell Center for Astrophysics and Planetary Science, in an email — although it is unlikely to happen before Titan's next summer, around 2047. By then, he said, there will be more ambient light and the submarine conceivably could communicate on a direct line to Earth with no need of an orbiting radio relay.

Titan is the weirdest place in the solar system, in some regards, and also the world most like our own. Like Earth, it has a thick atmosphere of mostly nitrogen (the only moon that has much of an atmosphere at all), and like Earth, it has weather, rain, rivers and seas. But on this world, when it rains, it rains gasoline. Hydrocarbon material drifts down like snow and is shaped into dunes by nitrogen winds. Rivers have carved canyons through mountains of frozen soot, and layers of ice float on subsurface oceans of ammonia. The prevailing surface temperature is minus 290 degrees Fahrenheit. A chemical sludge that optimistic astronomers call "prebiotic" creeps along under an oppressive brown sky. Besides Earth, Titan is the only world in the universe that is known to harbor liquid on its surface — with everything that could imply.

Mars

The Mars Perseverance Rover's Parachute Contained a Secret Message (apnews.com) 14

"The huge parachute used by NASA's Perseverance rover to land on Mars contained a secret message," reports the Associated Press — thanks to the rover's puzzle-loving systems engineer Ian Clark.

"During a live stream discussing the landing, one Nasa commentator said: 'Sometimes we leave messages in our work for others to find. So we invite you all to give it a shot and show your work,'" reports the Guardian.

One Reddit user actually deciphered the message using Python code.

Long-time Slashdot reader rufey writes that "Decoded the slogan is 'Dare Mighty Things' — a line from President Theodore Roosevelt — which is a mantra at JPL and adorns many of the center's walls." The orange sections of the 70-foot (21-meter) parachute represented ones in binary code, while the yellow sections represented zeroes. (So the letter "A" becomes yellow-yellow-yellow-yellow-yellow-yellow-orange...) The Associated Press reports: Clark also included the GPS coordinates for the mission's headquarters at the Jet Propulsion Laboratory in Pasadena, California. Clark, a crossword hobbyist, came up with the idea two years ago. Engineers wanted an unusual pattern in the nylon fabric to know how the parachute was oriented during descent. Turning it into a secret message was "super fun," he said Tuesday. Only about six people knew about the encoded message before Thursday's landing, according to Clark. They waited until the parachute images came back before putting out a teaser during a televised news conference Monday...

Another added touch not widely known until touchdown: Perseverance bears a plaque depicting all five of NASA's Mars rovers in increasing size over the years — similar to the family car decals seen on Earth.

Deputy project manager Matt Wallace promises more so-called hidden Easter eggs...

The official Twitter feed for the rover has already revealed that it's carrying another message hidden in a plaque with a logo of the sun — "Explore as One," written in Morse code.

Some other interesting facts about the rover:
Earth

Could Earth's Reversing Magnetic Poles Accelerate Climate Change? (cnn.com) 91

A team of researchers from Sydney's University of New South Wales and the South Australian Museum have investigated how the reversal of Earth's magnetic pole about 42,000 years could have changed earth's atmosphere. CNN reports: "Using the ancient trees we could measure, and date, the spike in atmospheric radiocarbon levels caused by the collapse of Earth's magnetic field," Chris Turney, a professor at UNSW Science, director of the university's Earth and Sustainability Science Research Center and co-lead author of the study, said in a statement. The team compared their new timescale with site records from caves, ice cores and peat bogs around the world. Researchers found that the reversal led to "pronounced climate change." Their modeling showed that ice sheet and glacier growth in North America and shifts in major wind belts and tropical storm systems could be traced back to the period of the magnetic pole switch, which scientists named the "Adams Event."

"Effectively, the Earth's magnetic field almost disappeared, and it opened the planet up to all these high energy particles from outer space. It would've been an incredibly scary time, almost like the end of days," Turney said. Researchers say the Adams Event could explain many of Earth's evolutionary mysteries, including the extinction of Neanderthals and the sudden widespread appearance of figurative art in caves worldwide... [T]he ionized air would've increased the frequency of electrical storms — something that scientists think caused humans to seek shelter in caves...

In the paper, published in the journal Science, experts say there is currently rapid movement of the north magnetic pole across the Northern Hemisphere — which could signal another reversal is on the cards. "This speed — alongside the weakening of Earth's magnetic field by around nine per cent in the past 170 years — could indicate an upcoming reversal," said Alan Cooper, honorary researcher at the South Australian Museum. "If a similar event happened today, the consequences would be huge for modern society. Incoming cosmic radiation would destroy our electric power grids and satellite networks," he said.

Human activity has already pushed carbon in the atmosphere to levels "never seen by humanity before," Cooper said. "A magnetic pole reversal or extreme change in Sun activity would be unprecedented climate change accelerants. We urgently need to get carbon emissions down before such a random event happens again," he added.

Space

Earth To Voyager 2: After a Year in the Darkness, We Can Talk To You Again (nytimes.com) 70

necro81 writes: Back in March 2020, NASA shut down the Australia dish in its Deep Space Network for repairs and upgrades. For the duration of the outage, NASA had no means for communicating with Voyager 2. From the NYTimes:

On Friday, Earth's haunting silence will come to an end as NASA switches that communications channel back on, restoring humanity's ability to say hello to its distant explorer.

Because of the direction in which it is flying out of the solar system, Voyager 2 can only receive commands from Earth via one antenna in the entire world. It's called DSS 43 and it is in Canberra, Australia. It is part of the Deep Space Network, or DSN, which along with stations in California and Spain, is how NASA and allied space agencies stay in touch with the armada of robotic spacecraft exploring everything from the sun's corona to the regions of the Kuiper belt beyond the orbit of Pluto. (Voyager 2's twin, Voyager 1, is able to communicate with the other two stations.)

A round-trip communication with Voyager 2 takes about 35 hours --17 hours and 35 minutes each way....

While Voyager 2 was able to call home on the Canberra site's smaller dishes during the shutdown, none of them could send commands to the probe....

NASA ... did send one test message to the spacecraft at the end of October when the antenna was mostly reassembled.


Science

Scientists Develop Transparent Wood That Is Stronger, Lighter Than Glass (www.cbc.ca) 91

Researchers at the University of Maryland have turned ordinary sheets of wood into transparent material that is nearly as clear as glass, but stronger and with better insulating properties. It could become an energy efficient building material in the future. CBC.ca reports: Wood is made of two basic ingredients: cellulose, which are tiny fibres, and lignin, which bonds those fibres together to give it strength. Tear a paper towel in half and look closely along the edge. You will see the little cellulose fibres sticking up. Lignin is a glue-like material that bonds the fibres together, a little like the plastic resin in fibreglass or carbon fibre. The lignin also contains molecules called chromophores, which give the wood its brown colour and prevent light from passing through.

Early attempts to make transparent wood involved removing the lignin, but this involved hazardous chemicals, high temperatures and a lot of time, making the product expensive and somewhat brittle. The new technique is so cheap and easy it could literally be done in a backyard. Starting with planks of wood a metre long and one millimetre thick, the scientists simply brushed on a solution of hydrogen peroxide using an ordinary paint brush. When left in the sun, or under a UV lamp for an hour or so, the peroxide bleached out the brown chromophores but left the lignin intact, so the wood turned white.

Next, they infused the wood with a tough transparent epoxy designed for marine use, which filled in the spaces and pores in the wood and then hardened. This made the white wood transparent. You can see a similar effect by taking that same piece of paper towel, dip half of it in water and place it on a patterned surface. The white paper towel will become translucent with light passing through the water and cellulose fibres without being scattered by refraction. The epoxy in the wood does an even better job, allowing 90 per cent of visible light to pass through. The result is a long piece of what looks like glass, with the strength and flexibility of wood.
The findings have been published in the journal Science Advances.
Transportation

German Institute Develops 'Powerpaste' That Stores Hydrogen Energy At 10x the Density of a Lithium Battery (hackaday.com) 124

A German research organization has developed a magnesium-based "Powerpaste" with an energy density ten times more than current battery technology. Hackaday reports: We've been promised hydrogen-powered engines for some time now. One downside though is the need for hydrogen vehicles to have heavy high-pressure tanks. While a 700 bar tank and the accompanying fuel cell is acceptable for a city bus or a truck, it becomes problematic with smaller vehicles, especially ones such as scooters or even full-sized motorcycles. The Fraunhofer Institute wants to run smaller vehicles on magnesium hydride in a paste form that they call POWERPASTE.

The idea is that the paste effectively stores hydrogen at normal temperature and pressure. At 250C, the paste decomposes and releases its hydrogen. While your motorcycle may seem hot when parked in the sun, it isn't getting quite to 250C. Interestingly, the paste only provides half the available hydrogen. The rest is from water added start a reaction to release the hydrogen. Fraunhofer claims the energy density available is greater than that of a 700 bar tank in a conventional hydrogen system and ten times more than current battery technology.

One thing that's attractive is that the paste is easy to store and pump. A gas station, for example, could invest $20-30,000 and dispense the paste from a metal drum to meet low demand and then scale up as needed. A hydrogen pumping setup starts at about $1.2 million. Fraunhofer is building a pilot production plant that will produce about four tons of the material a year.

Space

Why Do We Assume Extraterrestrials Might Want To Visit Us? (scientificamerican.com) 259

Avi Loeb, former chair of the astronomy department at Harvard University and who chairs the Board on Physics and Astronomy of the National Academies, writing at Scientific American: It is presumptuous to assume that we are worthy of special attention from advanced species in the Milky Way. We may be a phenomenon as uninteresting to them as ants are to us; after all, when we're walking down the sidewalk we rarely if ever examine every ant along our path. Our sun formed at the tail end of the star formation history [PDF] of the universe. Most stars are billions of years older than ours. So much older, in fact that many sunlike stars have already consumed their nuclear fuel and cooled off to a compact Earth-size remnant known as a white dwarf. We also learned recently that of order half [PDF] of all sunlike stars host an Earth-size planet in their habitable zone, allowing for liquid water and for the chemistry of life.

Since the dice of life were rolled in billions of other locations within the Milky Way under similar conditions to those on Earth, life as we know it is likely common. If that is indeed the case, some intelligent species may well be billions of years ahead of us in their technological development. When weighing the risks involved in interactions with less-developed cultures such as ours, these advanced civilizations may choose to refrain from contact. The silence implied by Fermi's paradox ("Where is everybody?") may mean that we are not the most attention-worthy cookies in the jar.

Space

Darkened SpaceX Satellites Can Still Disrupt Astronomy, New Research Suggests (gizmodo.com) 64

"SpaceX's attempt to reduce the reflectivity of Starlink satellites is working, but not to the degree required by astronomers," reports Gizmodo: Starlink satellites with an anti-reflective coating are half as bright as the standard version, according to research published in The Astrophysical Journal. It's an improvement, but still not good enough, according to the team, led by astronomer Takashi Horiuchi from the National Astronomical Observatory in Japan. These "DarkSats," as they're called, also continue to cause problems at other wavelengths of light [and] were included in a batch of satellites launched by SpaceX on January 7, 2020. The new study aimed to evaluate the effectiveness of that dark coating...

The scientists found that the "albedo of DarkSat is about a half of that of STARLINK-1113," as they wrote in their paper. That's a decent improvement in the visual spectrum, but still not great. What's more, problems persist at other wavelengths. "The darkening paint on DarkSat certainly halves reflection of sunlight compared to the ordinary Starlink satellites, but [the constellation's] negative impact on astronomical observations still remains," Horiuchi told Physics World. He said the mitigating effect is "good in the UV/optical region" of the spectrum, but "the black coating raises the surface temperature of DarkSat and affects intermediate infrared observations."

A third version of Starlink is supposed to be even dimmer. Called "VisorSats," they feature a sun visor that will "dim the satellites once they reach their operational altitude," according to Sky and Telescope. SpaceX launched some VisorSats last year, but the degree to which their albedo is lessened compared to the original version is still not known, or if these versions will exhibit elevated surface temperatures.

Horiuchi told Physics World that SpaceX should seriously consider lifting the altitude of the Starlink constellation to further reduce the brightness of these objects.

. The article ends with a quote from an astronomer at Harvard-Smithsonian Center for Astrophysics and an expert on satellites. He'd told Gizmodo's reporter back in January of 2020 that "SpaceX is making a good-faith effort to fix the problem," and that he believes the company "can get the satellites fainter than what the naked eye can see."
Math

Quixotic Californian Crusade To Officially Recognize the Hellabyte (theregister.com) 128

An anonymous reader quotes a report from The Register: In 2010, Austin Sendek, then a physics student at UC Davis, created a petition seeking recognition for prefix "hella-" as an official International System of Units (SI) measurement representing 10^27. "Northern California is home to many influential research institutions, including the University of California, Davis, the University of California, Berkeley, Stanford University, and the Lawrence Livermore and Lawrence Berkeley National Laboratories," he argued. "However, science isn't all that sets Northern California apart from the rest of the world. The area is also the only region in the world currently practicing widespread usage of the English slang 'hella,' which typically means 'very,' or can refer to a large quantity (e.g. 'there are hella stars out tonight')."

To this day, the SI describes prefixes for quantities for up to 10^24. Those with that many bytes have a yottabyte. If you only have 10^21 bytes, you have a zettabyte. There's also exabyte (10^18), petabyte (10^15), terabyte (10^12), gigabyte(10^9), and so on. Support for "hella-" would allow you to talk about hellabytes of data, he argues, pointing out that this would make the number of atoms in 12 kg of carbon-12 would be simplified from 600 yottaatoms to 0.6 hellaatoms. Similarly, the sun (mass of 2.2 hellatons) would release energy at 0.3 hellawatts, rather than 300 yottawatts. [...] The soonest [a proposal for a "hella-" SI could be officially adopted] is in November 2022, at the quadrennial meeting of the International Bureau of Weights and Measures (BIPM)'s General Conference on Weight and Measures, where changes to the SI usually must be agreed upon.
The report notes that Google customized its search engine in 2010 to let you convert "bytes to hellabytes." A year later, Wolfram Alpha added support for "hella-" calculations.

"Sendek said 'hellabyte' initially started as a joke with some college friends but became a more genuine concern as he looked into how measurements get defined and as his proposal garnered support," reports The Register. He believes it could be useful for astronomical measurements.
Microsoft

Microsoft Planning 'Sweeping Visual Rejuvenation of Windows' (theverge.com) 284

Microsoft is planning a "sweeping visual rejuvenation of Windows" that is designed to signal to users of the operating system that "Windows is BACK." From a report: That's according to a job listing posted by Microsoft recently, advertising for a software engineering role in the Windows Core User Experiences team: "On this team, you'll work with our key platform, Surface, and OEM partners to orchestrate and deliver a sweeping visual rejuvenation of Windows experiences to signal to our customers that Windows is BACK and ensure that Windows is considered the best user OS experience for customers." Microsoft quietly removed references to this "sweeping visual rejuvenation" this morning, after several Windows enthusiasts spotted the job listing over the weekend.
Medicine

Among 2020's Most Underreported Stories: Pharmaceutical Profiteering May Accelerate Superbugs (projectcensored.org) 86

Since 1976 "Project Censored," a U.S.-based nonprofit media watchdog organization, has been identifying "the news that didn't make the news," the most significant stories it believes are being systematically overlooked. Slashdot ran stories about its annual list of the year's most censored news stories in 1999, 2003, 2004, and in 2007, when they'd presciently warned that the media was ignoring the issue of net neutrality.

But their latest list of underreported stories includes this disturbing headline: "Antibiotic Abuse: Pharmaceutical Profiteering Accelerates Superbugs." Pharmaceutical giants Abbott and Sun Pharma are providing dangerous amounts of antibiotics to unlicensed doctors in India and incentivizing them to overprescribe. In August 2019 the Bureau of Investigative Journalism (BIJ) reported that these unethical business practices are leading to a rise in superbugs, or bacterial infections that are resistant to antibiotic treatment. Bacteria naturally evolve a resistance to antibiotics over time, but the widespread and inappropriate use of antibiotics accelerates this process. Superbugs are killing at least 58,000 babies each year and rendering a growing number of patients untreatable with all available drugs.

India's unlicensed medical practitioners, known as "quack" doctors, are being courted by Abbott and Sun Pharma, billion-dollar companies that do business in more than one hundred countries, including the United States. The incentives these companies provide to quack doctors to sell antibiotics have included free medical equipment, gift cards, televisions, travel, and cash, earning some doctors nearly a quarter of their salary. "Sales representatives would also offer extra pills or money as an incentive to buy more antibiotics, encouraging potentially dangerous overprescription," a Sun Pharma sales representative revealed to an undercover BIJ reporter... [P]atients without access to better care often turn to quack doctors for treatment, and many are unaware that their local medical "professionals" have no formal training and are being bribed to sell unnecessary antibiotics.

In September 2019, the BIJ reported on similar problems with broken healthcare systems, medical corruption, and dangerous superbugs in Cambodia. Their account describes how patients often request antibiotics for common colds, to pour onto wounds, and to feed to animals. Illegally practicing doctors and pharmacists in Cambodia admitted that they would often prescribe based on customer requests rather than appropriate medical guidelines. As the BIJ noted, "This kind of misuse speeds up the creation of drug resistant bacteria, or superbugs, which are predicted to kill 10 million people by 2050 if no action is taken...."

Although superbugs have attracted some attention, their cause and importance remain poorly understood by the public. The Independent and BuzzFlash republished the Bureau of Investigative Journalism's report; otherwise, the role of pharmaceutical companies in the rise of dangerous superbugs has been drastically underreported.

The site's list of the top 25 censored stories of 2019 - 2020 also includes:

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