schwit1 shares a report from New Atlas: UCF researchers say they've trapped a sustained explosive detonation, fixed in place, for the first time, channeling its enormous power into thrust in a new oblique wave detonation engine that could propel an aircraft up to 17 times the speed of sound, potentially beating the scramjet as a hypersonic propulsion method. [...] Rotating detonation engines, in which the shockwaves from one detonation are tuned to trigger further detonations within a ring-shaped channel, were thought of as impossible to build right up until researchers at the University of Central Florida (UCF) went ahead and demonstrated a prototype last year in sustained operation. Due for testing in a rocket launch by around 2025, rotating detonation engines should be more efficient than pulse detonation engines simply because the combustion chamber doesn't need to be cleared out between detonations.

Now, another team from UCF, including some of the same researchers that built the rotating detonation engine last year, says it's managed a world-first demonstration of an elusive third type of detonation engine that could out-punch them all, theoretically opening up a pathway to aircraft flying at speeds up to 13,000 mph (21,000 km/h), or 17 times the speedThe UCF team claims it has successfully stabilized a detonation wave under hypersonic flow conditions, keeping it in place rather than having it move upstream (where it could cause the fuel source to explode) or downstream (where it would lose its explosive advantage and fizzle out into a deflagration). [...] Where a detonation typically lasts only a matter of micro- or milliseconds, the UCF team managed to sustain this one experimentally until the fuel was turned off after around three seconds. That's long enough to prove the device works [...]. The paper is open-access at PNAS.

Elon Musk-founded SpaceX is in the process of rolling out Starlink as a satellite internet provider around the world. As part of a new partnership, Google Cloud data centers will be home to key Starlink infrastructure in order to let enterprise users better access key services. 9to5Google reports: This partnership starts with SpaceX building Starlink ground stations inside Google data centers for "secure, low-latency, and reliable delivery of data" from existing fiber networks to space and back to end users. There are currently over 1,500 Starlink satellites in orbit, with more launching on a regular basis aboard Falcon 9 rockets. The end goal is to make cloud services, data, and applications available to businesses in rural or remote areas: "Connectivity from Starlink's constellation of low-Earth-orbit satellites provides a path for these organizations to deliver data and applications to teams distributed across countries and continents, quickly and securely." The first Google Cloud and Starlink customers will be able to benefit from this partnership in the second half of 2021.

Computer hardware maker MSI is warning gamers not to visit a website that's impersonating the brand and its graphics card overclocking software, Afterburner, to push malware. From a report: On Thursday, MSI published a press release warning of "a malicious software being disguised as the official MSI Afterburner." "The malicious software is being unlawfully hosted on a suspicious website impersonating as MSI's official website with the domain name https:// afterburner - msi [ . ] space," the company wrote. "MSI has no relation with this website or the aforementioned domain. [...] This webpage is hosting software which may contain virus, trojan, keylogger, or other type of malicious program that have been disguised to look like MSI Afterburner," the company added. "DO NOT DOWNLOAD ANY SOFTWARE FROM THIS WEBSITE."

The beauty and misery of private RSS feeds. An anonymous reader shares a report: There's only supposed to be one way to hear exclusive podcast content from sports host Scott Wetzel: by paying $5 a month to subscribe to his Patreon. But the show's also been available on a smaller podcasting app for free. In fact, leaked podcast feeds from dozens of subscription-only shows, including Wetzel's and The Last Podcast On The Left, are available to stream through Castbox, a smaller app for both iOS and Android, just by searching for them.

Two people in the podcast space tell me they've reached out to Castbox multiple times, only for the company to remove a show and then have it pop up again, an infuriating cycle for someone trying to charge for their content. "It's a little bit like playing whack-a-mole with them," says one source, who asked to remain anonymous because of their ongoing work in the space. Podcast subscriptions have existed for years, but they've gained wider attention this past month. Apple, which makes the dominant podcasting app, introduced in-app subscriptions with a button that lets people directly subscribe to a show from the app. Spotify announced its own subscription product, too, but with caveats -- the main one being there's no actual in-app button.

System76 today unveiled its newest product -- the "Launch Configurable Keyboard." It is a mechanical keyboard made in the USA with a focus on open source. The Launch has both open source firmware and hardware. Even the configuration software -- which runs on Linux, Windows, and macOS -- is open source. From a report: "With a wide swath of customization options, the Launch is flexible to a variety of needs and use cases. The keyboard's thoughtful design keeps everything within reach, vastly reducing awkward hand contortions. Launch comes with additional keycaps and a convenient keycap puller, meaning one can swap keys based on personal workflow preferences to maximize efficiency. Launch also features a novel split Space Bar, which allows the user to swap out one Space Bar keycap for Shift, Backspace, or Function to reduce hand fatigue while typing. Launch uses only three keycap sizes to vastly expand configuration options," says System76. The keyboard, which has a removable USB-C cable for connectivity, is priced at $285.

NASA and Houston-based Axiom Space have signed a "mission order" setting the stage for four civilians to visit the International Space Station early next year, the first fully commercial flight to the orbiting lab complex, agency managers said Monday. CBS News reports: Axiom's "AX-1" mission and an upcoming charity-driven flight to low-Earth orbit, both aboard SpaceX Crew Dragon capsules, represent "a renaissance in U.S. human spaceflight," said Phil McAlister, NASA's director of commercial spaceflight development. "I think that's the perfect word for what we're experiencing," he said of the growing commercial space market, which includes the anticipated certification of Boeing's CST-100 Starliner and upcoming sub-orbital flights by Blue Origin and Virgin Galactic. "This is a real inflection point, I think, with human spaceflight."

Axiom Space, led by Mike Suffredini, NASA's former space station program manager, announced last year that it plans to launch a four-man crew to the space station aboard a SpaceX Crew Dragon capsule. The launch is currently targeted for a January timeframe. Axiom Vice President Mike Lopez-Alegria, a former NASA astronaut and space station commander, will serve as commander of the AX-1 mission, which is expected to last about 10 days. Joining him will be Larry Connor, an American entrepreneur, Canadian investor and philanthropist Mark Pathy and Israeli investor Eytan Stibbe, a former fighter pilot.

Lopez-Alegria on Monday told reporters that the crew will participate in centrifuge training and flights to simulate weightlessness starting next week, followed by a camping trip to Alaska in July for "bonding and leadership training." Lopez-Alegria and Connor, the mission pilot, will begin SpaceX flight training shortly thereafter before the entire crew begins space station familiarization at the Johnson Space Center in October. [...] Axiom is not paying list price for the AX-1 mission, in part because planning began before the new price guidelines were determined and because the company will be providing services to NASA that the agency would otherwise have to pay for. The mission order announced Monday covers just $1.69 million. Additional agreements remain to be negotiated.

An anonymous reader quotes a report from Ars Technica: This week, the academic community provided a rather impressive example of the promise of neural implants. Using an implant, a paralyzed individual managed to type out roughly 90 characters per minute simply by imagining that he was writing those characters out by hand. Somewhere in our writing thought process, we form the intention of using a specific character, and using an implant to track this intention could potentially work. Unfortunately, the process is not especially well understood. Downstream of that intention, a decision is transmitted to the motor cortex, where it's translated into actions. Again, there's an intent stage, where the motor cortex determines it will form the letter (by typing or writing, for example), which is then translated into the specific muscle motions required to perform the action. These processes are much better understood, and they're what the research team targeted for their new work. Specifically, the researchers placed two implants in the premotor cortex of a paralyzed person. This area is thought to be involved in forming the intentions to perform movements. Catching these intentions is much more likely to produce a clear signal than catching the movements themselves, which are likely to be complex (any movement involves multiple muscles) and depend on context (where your hand is relative to the page you're writing on, etc.). With the implants in the right place, the researchers asked the participant to imagine writing letters on a page and recorded the neural activity as he did so.

Altogether, there were roughly 200 electrodes in the participant's premotor cortex. Not all of them were informative for letter-writing. But for those that were, the authors performed a principal component analysis, which identified the features of the neural recordings that differed the most when various letters were imagined. Converting these recordings into a two-dimensional plot, it was obvious that the activity seen when writing a single character always clustered together. And physically similar characters -- p and b, for example, or h, n, and r -- formed clusters near each other. (The researchers also asked the participant to do punctuation marks like a comma and question mark and used a > to indicate a space and a tilde for a period.) Overall, the researchers found they could decipher the appropriate character with an accuracy of a bit over 94 percent, but the system required a relatively slow analysis after the neural data was recorded. To get things working in real time, the researchers trained a recurrent neural network to estimate the probability of a signal corresponding to each letter.

Despite working with a relatively small amount of data (only 242 sentences' worth of characters), the system worked remarkably well. The lag between the thought and a character appearing on screen was only about half a second, and the participant was able to produce about 90 characters per minute, easily topping the previous record for implant-driven typing, which was about 25 characters per minute. The raw error rate was only about 5 percent, and applying a system like a typing autocorrect could drop the error rate down to only 1 percent. The tests were all done with prepared sentences. Once the system was validated, however, the researchers asked the participant to type out free-form answers to questions. Here, the speed went down a bit (to 75 characters a minute) and errors went up to 2 percent after autocorrection, but the system still worked. The findings have been published in the journal Nature.

In Vizio's first public earnings report today, the company revealed that in the first three months of 2021, profits from its Platform+ business -- the part that sells viewer data and advertising space via the SmartCast platform -- were $38.4 million. Engadget reports: As execs said on the call, the company continues to court relationships with brands and agencies, following the same plan laid out six years ago with a business built on its Inscape Automated Content Recognition tech. Its device business (the part that sells TVs, sound bars and the like) had a gross profit of $48.2 million in the same period, up from $32.5 million last year. While the hardware business has significantly more revenue, profits from data and advertising spiked 152 percent from last year, and are quickly catching up.

Vizio did say that hardware profits were affected by products getting stuck at ports due to a shipping glut that has impacted many companies over the last year, buts forecast is that Platform+ revenue and profit will continue to grow in Q2, as device profit margins "trend toward the single digits." Vizio said it now has 13.4 million active SmartCast accounts, with viewers spending 52 percent of their viewing time on SmartCast inputs (the built-in apps, or casting from another device). 34 percent of viewing time went to linear TV, with 7 percent for game consoles or over the top devices. If you have a Vizio TV, you can opt out of anonymized tracking by following these steps.

NASA engineers are getting one last look at the James Webb Space Telescope (JWST): a final test to show that its 18 gold-tinted mirror segments can unfold into a precise honeycomb configuration. From a report: After the test concludes this week, the giant instrument will be folded up, packed into a shipping container, and shipped off to French Guiana, where it will launch into space on 31 October. The 6.5-meter-wide JWST is the agency's next great observatory, the successor to the Hubble Space Telescope.

In a NASA briefing this week, Program Scientist Eric Smith told reporters it was born out of a realization in the mid-1990s that, no matter how long it stared into deep space, Hubble would never be able to see the universe's very first stars and galaxies and learn how they formed and evolved. The expanding universe has "redshifted" the light of those primordial objects out of the visible spectrum; NASA needed a space telescope that worked in the infrared. "So the idea of Webb was born," Smith says. Since then, astronomers have discovered thousands of exoplanets. Smith says JWST will be able to probe their atmospheres for molecules such as carbon dioxide, water, methane, and others that could suggest the presence of life.

Getting the $9 billion contraption to the point of departure has taken NASA much more time and money than it or Congress ever suspected. The construction of JWST proved to be the most complex and difficult science project in the agency's history. The process of testing the telescope's folding mirror, multilayered sunshield, and cryogenically cooled instruments has stretched years longer than planned. But come late August, all that will be over as JWST, in a protective cocoon, will be taken from Northrop Grumman's facility in Redondo Beach, California, and put onto a ship. The telescope will sail through the Panama Canal to Europe's spaceport near Kourou. Unlike the 2.4-meter-wide Hubble, which fit comfortably inside the bay of the Space Shuttle, JWST's mirror is much larger than the fairing on top of an Ariane 5 rocket, so it is elaborately folded to fit inside it.

Obipale shares a press release from NASA: After nearly five years in space, NASA's Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) spacecraft is on its way back to Earth with an abundance of rocks and dust from the near-Earth asteroid Bennu. On Monday, May 10, at 4:23 p.m. EDT the spacecraft fired its main engines full throttle for seven minutes -- its most significant maneuver since it arrived at Bennu in 2018. This burn thrust the spacecraft away from the asteroid at 600 miles per hour (nearly 1,000 kilometers per hour), setting it on a 2.5-year cruise towards Earth. After releasing the sample capsule, OSIRIS-REx will have completed its primary mission. It will fire its engines to fly by Earth safely, putting it on a trajectory to circle the sun inside of Venus' orbit. After orbiting the Sun twice, the OSIRIS-REx spacecraft is due to reach Earth Sept. 24, 2023. Upon return, the capsule containing pieces of Bennu will separate from the rest of the spacecraft and enter Earth's atmosphere. The capsule will parachute to the Utah Test and Training Range in Utah's West Desert, where scientists will be waiting to retrieve it.

"OSIRIS-REx's many accomplishments demonstrated the daring and innovate way in which exploration unfolds in real time," said Thomas Zurbuchen, associate administrator for science at NASA Headquarters. "The team rose to the challenge, and now we have a primordial piece of our solar system headed back to Earth where many generations of researchers can unlock its secrets." To realize the mission's multi-year plan, a dozen navigation engineers made calculations and wrote computer code to instruct the spacecraft when and how to push itself away from Bennu. After departing from Bennu, getting the sample to Earth safely is the team's next critical goal. This includes planning future maneuvers to keep the spacecraft on course throughout its journey.

Southern California has adopted a new air pollution rule aimed at slashing noxious emissions from warehouse trucks that move goods sold by Amazon and other e-commerce retailers. Ars Technica reports: Diesel pollution from heavy trucks causes everything from asthma to heart attacks, and even Parkinson's disease. Previously, such pollution tended to be concentrated around shipping ports and highways, but the growth of e-commerce has created a new source that is affecting neighborhoods farther inland. There are nearly 34,000 warehouses enclosing 1.17 billion square feet of space in the Los Angeles region alone. The rule, which was adopted late last week by a 9-4 vote of the South Coast Air Quality Management District (AQMD), would cover around 3,300 warehouses that are larger than 100,000 square feet. The rule seeks to reduce the amount of diesel particulate matter and nitrogen oxides produced by trucks serving these facilities. The district covers more than 17 million people, or nearly half the state's population.

The way the South Coast AQMD is approaching warehouse-related pollution is novel. Rather than attempting to control traffic flow to and from the facilities, the regulator will require warehouse owners to take various steps to reduce pollution in the area. That could include buying electric or fuel-cell trucks, adding solar panels to the building roofs, or installing air filters at nearby homes, hospitals, and schools. Each of these measures is assigned a point value, and warehouse operators must achieve a certain total to offset the emissions from their truck traffic. If they cannot meet the goal through mitigation measures, they can pay a fee instead. South Coast AQMD is phasing in compliance depending on the size of the facility. Warehouses that are over 250,000 square feet must meet their goals by June 30, 2022. Warehouses over 150,000 square feet must comply by the same day the following year, and those over 100,000 square feet get until June 30, 2024. Amazon's typical warehouses, for example, range in size from 600,000 to 1 million square feet. [...] The new rule is expected to save 150 to 300 lives and prevent 2,500 to 5,800 asthma attacks between 2022 and 2031. Overall, the public health benefits could be as large as $2.7 billion over the same timeframe.

Obipale shares a report from Phys.Org: Voyager 1 -- one of two sibling NASA spacecraft launched 44 years ago and now the most distant human-made object in space -- still works and zooms toward infinity. The craft has long since zipped past the edge of the solar system through the heliopause -- the solar system's border with interstellar space -- into the interstellar medium. Now, its instruments have detected the constant drone of interstellar gas (plasma waves), according to Cornell University-led research published in Nature Astronomy.

Examining data slowly sent back from more than 14 billion miles away, Stella Koch Ocker, a Cornell doctoral student in astronomy, has uncovered the emission. "It's very faint and monotone, because it is in a narrow frequency bandwidth," Ocker said. "We're detecting the faint, persistent hum of interstellar gas." This work allows scientists to understand how the interstellar medium interacts with the solar wind, Ocker said, and how the protective bubble of the solar system's heliosphere is shaped and modified by the interstellar environment.

This week Linus Torvalds continued a long email interview with Jeremy Andrews, founding partner/CEO of Tag1 (a global technology consulting firm and the second all-time leading contributor to Drupal). In the first part Torvalds had discussed everything from Apple's ARM64 chips and Rust drivers, to his own Fedora-based home work environment — and reflections on the early days of Linux.

But the second part offers some deeper insight into the way Torvalds thinks, some personal insight, what he'd share with other project maintainers — and some thoughts on getting corporations to contribute to open source development: While open source has been hugely successful, many of the biggest users, for example corporations, do nothing or little to support or contribute back to the very open source projects they rely on. Even developers of surprisingly large and successful projects (if measured by number of users) can be lucky to earn enough to buy coffee for the week. Do you think this is something that can be solved? Is the open source model sustainable?

Linus Torvalds: I really don't have an answer to this, and for some reason the kernel has always avoided the problem. Yes, there are companies that are pure "users" of Linux, but they still end up wanting support, so they then rely on contractors or Linux distributions, and those obviously then end up as one of the big sources of kernel developer jobs.

And a fair number of big tech companies that use the kernel end up actively participating in the development process. Sometimes they end up doing a lot of internal work and not being great at feeding things back upstream (I won't name names, and some of them really are trying to do better), but it's actually very encouraging how many big companies are very openly involved with upstream kernel development, and are major parts of the community.

So for some reason, the kernel development community has been pretty successful about integrating with all the commercial interests. Of course, some of that has been very much conscious: Linux has very much always been open to commercial users, and I very consciously avoided the whole anti-corporate mindset that you can most definitely find in some of the "Free Software" groups. I think the GPLv2 is a great license, but at the same time I've been very much against some of the more extreme forms of "Free Software", and I — and Linux — was very much part of the whole rebranding to use "Open Source".

Because frankly, some of the almost religious overtones of rms and the FSF were just nutty, and a certain portion of the community was actively driving commercial use away.

And I say that as somebody who has always been wary of being too tainted by commercial interests... I do think that some projects may have shot themselves in the foot by being a bit too anti-commercial, and made it really hard for companies to participate...

But is it sustainable? Yes. I'm personally 100% convinced that not only is open source sustainable, but for complex technical issues you really need open source simply because the problem space ends up being too complex to manage inside one single company. Even a big and competent tech company.

But it does require a certain openness on both sides. Not all companies will be good partners, and some developers don't necessarily want to work with big companies.
In the interview Torvalds also thanks the generous education system in Finland, and describes what it was like moving from Finland to America. And as for how long he'll continue working on Linux, Torvalds says, "I do enjoy what I do, and as long as I feel I'm actually helping the project, I'll be around...

"in the end, I really enjoy what I do. I'd be bored to tears without kernel development."

"The Linux Foundation has lifted the lid on a new open source digital infrastructure project aimed at the agriculture industry," reports VentureBeat: The AgStack Foundation, as the new project will be known, is designed to foster collaboration among all key stakeholders in the global agriculture space, spanning private business, governments, and academia.

As with just about every other industry in recent years, there has been a growing digital transformation across the agriculture sector that has ushered in new connected devices for farmers and myriad AI and automated tools to optimize crop growth and circumvent critical obstacles, such as labor shortages. Open source technologies bring the added benefit of data and tools that any party can reuse for free, lowering the barrier to entry and helping keep companies from getting locked into proprietary software operated by a handful of big players...

The AgStack Foundation will be focused on supporting the creation and maintenance of free and sector-specific digital infrastructure for both applications and the associated data. It will lean on existing technologies and agricultural standards; public data and models; and other open source projects, such as Kubernetes, Hyperledger, Open Horizon, Postgres, and Django, according to a statement.

"Current practices in AgTech are involved in building proprietary infrastructure and point-to-point connectivity in order to derive value from applications," AgStack executive director Sumer Johal told VentureBeat. "This is an unnecessarily costly use of human capital. Like an operating system, we aspire to reduce the time and effort required by companies to produce their own proprietary applications and for content consumers to consume this interoperably."

Several science web sites are strongly disputing a China-based journal's claim that time-lapse photos of Mars show growing mushrooms.

TNW Neural headlined their story "Mushrooms on Mars is a hoax — stop believing hack 'scientists'" If you believe those images demonstrate fungus growing on Mars, I'm about to blow your frickin' mind. Check out this pic. You see that? To heck with fungus, that's an entire highway growing out of the sand in front of a moving bus. You can clearly see that the Earth's sandy crust is being broken apart as the expanding highway organism grows beneath it.

Or, if you're the "Occam's Razor" type: the wind is just blowing sand around. I've never been to Mars, but I'm led to believe there are rocks, dust, and wind. Do we really need to go any further in debunking this nonsense?
They also link to Retraction Watch's page about the story's lead author, Rhawn Gabriel Joseph. IFL Science picks up the story: Nicknamed the Space Tiger King — due to the photographs posted on his frankly ridiculous personal website — Joseph has spent decades erroneously claiming that life has already been discovered on other planets. Back in the 1970s, he began alleging that NASA's Viking lander had found biological matter, despite the agency stating the exact opposite of this.

After setting up his own journal in an attempt to air his unscientific assertions, he later filed a lawsuit against NASA in order to force them to investigate a structure which he claimed resembled a "putative biological organism", but which later turned out to be a rock.
CNET adds: "Claiming that mushrooms are sprouting all over Mars is an extraordinary claim that requires better evidence than an analysis of photographic morphology by a known crank who has claimed, on the basis of the same kind of analysis, that he has seen fields of skulls on Mars," says Paul Myers, a developmental biologist at the University of Minnesota, Morris, who has followed Joseph's work in the past...

After being alerted to the new paper on Wednesday, I sent emails to the associate editors-in-chief of Advances in Microbiology, asking for clarification around the peer review process. They have not responded to requests for comment. I also emailed members of the editorial board listed on SCIRP's website, including Jian Li, a microbiologist at Monash University in Australia. He says he has not been on the journal's editorial board "for at least five to six years" and has not handled any of the papers in the journal.
The "mushrooms" theory was also dismissed by several actual scientists, reports Futurism: "The conditions on Mars are so extreme that you're not going to see fungi or any kind of life growing at that sort of speed under conditions like coldness and low air pressure," Jonathan Clarke, president of Mars Society Australia, told the South China Morning Post. "Life can barely survive, let alone thrive."

Clarke also took issue with the paper claiming that mushrooms were actually growing on Mars. "It's just like if you go to a beach and there are shells," he told the newspaper. "If the wind blows, the sand moves and exposes more shells. But we won't say the shells are growing there, it's just that they become visible..."

"We have more than photos, records, instruments that tell us what these materials are made of," David Flannery, lecturer at the Queensland University of Technology who is a member of NASA's Mars 2020 mission science team, told SCMP. "And we have models for the features we see around us.... Robots are sending back huge amounts of data," he added. "We have plenty of information but it's just that no one is interpreting the features that we see as something like fungi. There's zero evidence for that."

"This paper, which is really not credible, will be ignored by the scientific community," Flannery said.

An out-of-control Chinese rocket plunged out of orbit and reentered Earth's atmosphere in the Indian Ocean (just west of the Maldives), reports CNN, citing China's space agency: Most of the rocket was "destroyed" on reentry to the atmosphere, the space agency said. The rocket, which is about 108 feet tall and weighs nearly 40,000 pounds, had launched a piece of a new Chinese space station into orbit on April 29.

After its fuel was spent, the rocket had been left to hurtle through space uncontrolled until Earth's gravity dragged it back to the ground.

Generally, the international space community tries to avoid such scenarios. Most rockets used to lift satellites and other objects into space conduct more controlled reentries that aim for the ocean, or they're left in so-called "graveyard" orbits that keep them in space for decades or centuries. But the Long March rocket is designed in a way that "leaves these big stages in low orbit," said Jonathan McDowell, an astrophysicist at the Astrophysics Center at Harvard University.

In this case, it was impossible to be certain exactly when or where the booster would land. The European Space Agency had predicted a "risk zone" that encompassed "any portion of Earth's surface between about 41.5N and 41.5S latitude" — which included virtually all of the Americas south of New York, all of Africa and Australia, parts of Asia south of Japan and Europe's Spain, Portugal, Italy and Greece. The threat to populated areas of land was not negligible, but fortunately the vast majority of Earth's surface area is consumed by oceans...

The rocket is one of the largest objects in recent memory to strike the Earth after falling out of orbit, following a 2018 incident in which a piece of a Chinese space lab broke up over the Pacific Ocean and the 2020 reentry of an 18-metric-ton Long March 5B rocket [also launched by China].

"Getting to another extrasolar planet is never going to happen in my lifetime, or that of Western civilisation," says Alan Jackson, an astronomer and planetary scientist at Arizona State University. "But we can have nature deliver pieces of them to us that we can actually see up close."

Slashdot reader boudie2 shares this article from BBC Future, which notes that astronomers spent decades looking for objects from outside our solar system — until two arrived at once. "'Oumuamua has not yet been definitively classified as a comet or an asteroid — it might be something else entirely," the article points out. For one thing, 'Oumuamua didn't have a comet-like tail: Two things in particular fixated scientists. The first was its mysterious acceleration away from the Sun, which was hard to reconcile with many ideas about what it might have been made of. The second was its peculiar shape — by some estimates, it was 10 times as long as it was wide. Before 'Oumuamua, the most elongated known space objects were three times longer than they were wide... [F]inally, earlier this year Jackson and his colleague Steven Desch came up with an explanation that seems to explain 'Oumuamua's quirky features, without the need for any alien technology... "We just realised that nitrogen ice could supply exactly the amount of push it needs — and it's observed on Pluto," he says. To corroborate the idea, they calculated how shiny the surface of 'Oumuamua was and compared it to the reflectivity of nitrogen ice — and found that the two were more or less exact matches.

The team concluded that the object was likely to be a chunk of nitrogen ice, which was chipped off the surface of a Pluto-like exoplanet around a young star. Based on the evolution of our own solar system, which started out with thousands of similar planets in the icy neighbourhood of the Kuiper belt, they suggested that the fragment may have broken off around half a billion years ago...

Though the object would have finally reached the very outermost edge of the Solar System many years ago, it would have taken a long time to travel to the balmy, central region where it was first discovered — and been gradually worn down into a pancake as it approached. This explains its unusual shape and its acceleration in one go, because the evaporating nitrogen would have left an invisible tail that propelled it forwards. "Our atmosphere is mostly nitrogen and you can see though it," says Jackson. "Nitrogen gas is difficult to detect."

Again, not everyone is happy with this suggestion.
Luckily, the second interstellar object, 2I/Borisov "has turned out to be emphatically less difficult to decipher than its cosmic companion. It's been recognised as the first interstellar comet ever found."

An anonymous reader quotes a report from TechCrunch: SpaceX is fresh off a high for its Starship spacecraft development program, but according to CEO Elon Musk, it's already looking ahead to potentially repeating its latest success with an unplanned early reusability experiment. Earlier this week, SpaceX flew the SN15 (i.e. 15th prototype) of its Starship from its development site near Brownsville, Texas, and succeeded in landing it upright for the first time. Now, Musk says they could fly the same prototype a second time, a first for the Starship test and development effort.

A second test flight of SN15 is an interesting possibility among the options for the prototype. SpaceX will obviously be conducting a number of other check-outs and gathering as much data as it can from the vehicle, in addition to whatever it collected from onboard sensors, but the options for the craft after that basically amounted to stress testing it to failure, or dismantling it and studying the pieces. A second flight attempt is an interesting additional option that could provide SpaceX with a lot of invaluable data about its planned re-use of the production version of Starship.

schwit1 writes: Are there aliens out there? Breakthrough Listen, a privately-funded project searching for evidence of alien life, has released the first results from its survey of 60 million stars in an area looking towards the galactic center, noting that it found no evidence of any technological transmissions signaling an alien civilization from any of those stars. The kind of signals they were looking for were not beacons sent out intentionally by alien civilizations, such as television or radio broadcasts, but unintentional transmissions, such as radar transmissions meant for other purposes but still beamed into space. They found none. The paper can be downloaded here (PDF).

schwit1 shares a report from IEEE Spectrum, written by Evan Ackerman: A few weeks ago, the CTO of Cruise tweeted an example of one of their AVs demonstrating a safety behavior where it moves over to make room for a cyclist. What's interesting about this behavior, though, is that the AV does this for cyclists approaching rapidly from behind the vehicle, something a human is far less likely to notice, much less react to. A neat trick -- but what does it mean, and what's next? In the video [here], as the cyclist approaches from the rear right side at a pretty good clip, you can see the autonomous vehicle pull to the left a little bit, increasing the amount of space that the cyclist can use to pass on the right.

One important question that we're not really going to tackle here is whether this is even a good idea in the first place, since (as a cyclist) I'd personally prefer that cars be predictable rather than sometimes doing weirdly nice things that I might not be prepared for. But that's one of the things that makes cyclists tricky: we're unpredictable. And for AVs, dealing with unpredictable things is notoriously problematic. Cruise's approach to this, explains Rashed Haq, VP of Robotics at Cruise, is to try to give their autonomous system some idea of how unpredictable cyclists can be, and then plan its actions accordingly. Cruise has collected millions of miles of real-world data from its sensorized vehicles that include cyclists doing all sorts of things. And their system has built up a model of how certain it can be that when it sees a cyclist, it can accurately predict what that cyclist is going to do next.

Essentially, based on its understanding of the unpredictability of cyclists, the Cruise AV determined that the probability of a safe interaction is improved when it gives cyclists more space, so that's what it tries to do whenever possible. This behavior illustrates some of the critical differences between autonomous and human-driven vehicles. Humans drive around with relatively limited situational awareness and deal with things like uncertainty primarily on a subconscious level. AVs, on the other hand, are constantly predicting the future in very explicit ways. Humans tend to have the edge when something unusual happens, because we're able to instantly apply a lifetime's worth of common-sense knowledge about the world to our decision-making process. Meanwhile, AVs are always considering the safest next course of action across the entire space that they're able to predict.