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  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.
  • warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Los_Angeles' for 'PST/-8.0/no DST' instead in /nfs/cristina/home1/b/brian/public_html/drupal-6.28/modules/aggregator/aggregator.pages.inc on line 259.

Scientists test medieval gunpowder recipes with 15th-century cannon replica

ArsTechnica - Wed, 09/29/2021 - 2:27pm
Researchers tested medieval gunpowder recipes in this replica of an early 15th-century stone-throwing cannon.

Enlarge / Researchers tested medieval gunpowder recipes in this replica of an early 15th-century stone-throwing cannon. (credit: T.S. Ritchie et al., ACS Omega 2021)

Gunpowder—as opposed to modern smokeless powder—isn't used much these days in current weaponry, although it's still useful for historical weapons and remains popular for fireworks and other pyrotechnics. An interdisciplinary team of chemists and historians wanted to learn more about how various recipes for gunpowder evolved over the centuries as master gunners tweaked the basic components to achieve better results. The researchers described their findings in a recent paper published in the journal ACS Omega. They even tested a few of the recipes by firing a replica of a 15th-century stone-throwing cannon at a West Point firing range—you know, for science.

Also known as black powder, gunpowder is simple enough, chemically speaking. It's a mix of sulfur and charcoal (carbon), which serve as fuels, and potassium nitrate (KNO3), an oxidizer also known as saltpeter. First used for warfare around 904 CE in China, its use had spread throughout Europe and Asia by the late 13th century. Modern black powder recipes call for 75 percent saltpeter, 15 percent charcoal, and 10 percent sulfur. But medieval master gunners experimented with many different recipes over the centuries, many of which included additives such as camphor, varnish, or brandy—the purpose of which is still unknown.

By the late 14th century, manufacturers had discovered that one could improve the performance of gunpowder through a wet-grinding process called "corning." Some kind of liquid (often distilled spirits) would be added as the other ingredients were being ground together, producing a moist paste. The paste would be rolled into balls and then dried, and those balls would be crushed in a mortar by a gunner in the field right before it was used.

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YouTube bans vaccine nonsense, such as claims that vaccines alter genetic makeup

ArsTechnica - Wed, 09/29/2021 - 1:50pm
A healthcare worker preparing a COVID-19 vaccine.

Enlarge / A COVID-19 vaccine. (credit: Getty Images | Morsa Images)

YouTube is banning a wide range of anti-vaccine misinformation, saying it will remove videos that falsely claim vaccines cause diseases or alter people's genetic makeup, that vaccines are used to track people, or that vaccines "are part of a depopulation agenda."

"Specifically, content that falsely alleges that approved vaccines are dangerous and cause chronic health effects, claims that vaccines do not reduce transmission or contraction of disease, or contains misinformation on the substances contained in vaccines will be removed," the Google-owned YouTube said in today's announcement. "This would include content that falsely says that approved vaccines cause autism, cancer or infertility, or that substances in vaccines can track those who receive them. Our policies not only cover specific routine immunizations like for measles or Hepatitis B, but also apply to general statements about vaccines."

Robert F. Kennedy Jr. was among the first purveyors of anti-vaccine misinformation to have a channel removed from YouTube today.

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Hot Wheels Unleashed game review: The good, the bad, and the tiny

ArsTechnica - Wed, 09/29/2021 - 1:34pm

This week's Hot Wheels Unleashed is one of the best video games ever made using licensed toy cars. To be fair, that specific concept isn't necessarily common in gaming, but Codemasters' legendary Micro Machines series holds a lot of water for a certain type of arcade-racing fan. That's decent company to land in.

Yet while handsomely modeled toy cars and cute environments might look like a basis for newbie-friendly racing, it's not the case here. In my week of testing the game ahead of its launch this week, I found that Hot Wheels Unleashed feels like a Micro Machines skin on top of the modern, hardcore-leaning Trackmania series. That's not a bad thing—and I had a good-enough time with Unleashed to write about it at Ars, as I think some people will really enjoy what's going on here.

But you'll have a better time with HWU going into it fully aware of its weird and tricky design decisions—along with quibbles about its in-game economy of cars and tracks.

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Phone companies must now block carriers that didn’t meet FCC robocall deadline

ArsTechnica - Wed, 09/29/2021 - 10:43am
Smartphone screen displays

Enlarge (credit: Getty Images | RobertAx)

In a new milestone for the US government's anti-robocall efforts, phone companies are now prohibited from accepting calls from providers that did not comply with a Federal Communications Commission deadline that passed this week. "Beginning today, if a voice service provider's certification and other required information does not appear in the FCC's Robocall Mitigation Database, intermediate providers and voice service providers will be prohibited from directly accepting that provider's traffic," the FCC said yesterday.

Specifically, phone companies must block traffic from other "voice service providers that have neither certified to implementation of STIR/SHAKEN caller ID authentication standards nor filed a detailed robocall mitigation plan with the FCC." As we've written, the STIR (Secure Telephone Identity Revisited) and SHAKEN (Signature-based Handling of Asserted Information Using toKENs) protocols verify the accuracy of Caller ID by using digital certificates based on public-key cryptography.

STIR/SHAKEN is now widely deployed on IP networks because large phone companies were required to implement it by June 30 this year, but it isn't a cure-all. Because of technology limitations, there was no requirement to implement STIR/SHAKEN on older TDM-based networks used with copper landlines, for instance. The FCC has said that "providers using older forms of network technology [must] either upgrade their networks to IP or actively work to develop a caller ID authentication solution that is operational on non-IP networks."

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Malaria seems to be evolving to hide from rapid tests

ArsTechnica - Wed, 09/29/2021 - 10:09am
A hand in a protective glove handles test kits and samples.

Enlarge / A technician performs rapid tests for malaria in Thailand. (credit: Thierry Falise / Getty Images)

The pandemic has introduced a lot of people to the idea of rapid antigen tests, which can quickly and conveniently reveal the presence of an infection. But in many parts of the world, rapid tests are a central feature of health care. If you don't have easy access to a testing lab infrastructure—and many in the developing world don't—rapid tests can provide a quick way of screening for common problems. In a number of countries, rapid test results are what determine whether people are given anti-malaria treatments or not.

But that may be causing a unique problem. A new paper suggests that the malarial parasite may be evolving so that it can't be recognized by the most commonly used rapid tests.

Make it quick

Most rapid tests detect the presence of one or more proteins on the surface of a pathogen. We can mass-produce antibodies that recognize this protein and couple them to a molecule that is colored. When a pathogen isn't present, the antibodies remain diffuse, and the color is imperceptible. When the pathogen is around, its protein and the antibodies aggregate, bringing enough of the colored molecule together that we can see it. The result is something like a red bar appearing at a specific location on the test hardware.

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Google Maps tracks global warming with new “Fire” layer, Tree Canopy tool

ArsTechnica - Wed, 09/29/2021 - 10:00am

Google Maps is getting a few new features to help people better understand our burning planet. The first is a new "fire" layer in the main map view, which will let you view the exact boundaries of a wildfire just as easily as you can look up the current traffic patterns. Google has done fire information before as part of the "crisis response" website, but with climate change making "Fire Season" a yearly occurrence in dry areas like Australia and the Western US, wildfires will now be a top-level Maps feature.

Google says the new fire level will bring "all of Google’s wildfire information together" in an easy interface. In the US, it will also pull in data from the National Interagency Fire Center (NIFC), and the company says it wants to expand fire detail with other government agencies, starting with Australia in "the coming months." Wildfire boundaries should be updated on an hourly basis, and Google says you'll be able to tap on a fire to see information from local governments, like "emergency websites, phone numbers for help and information, and evacuation details. When available, you can also see important details about the fire, such as its containment, how many acres have burned, and when all this information was last reported."

The fire layout is rolling out to Android this week, with iOS and desktop coming in October.

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Epic Games Store, Discord, and Zoom all join Windows 11’s more flexible app store

ArsTechnica - Wed, 09/29/2021 - 9:47am
The Microsoft Store in Windows 11.

Enlarge / The Microsoft Store in Windows 11. (credit: Microsoft)

When Microsoft introduced Windows 11 over the summer, it also detailed a major shift in strategy for its app store. In an effort to woo more developers and their apps after years of indifference, Microsoft said it would allow all kinds of apps developed and packaged with all kinds of tools into the Microsoft Store, including everything from traditional Win32 apps to Electron apps to progressive web apps (PWAs).

Now we're seeing some of the fruits of that change—Microsoft has announced that major third-party apps like Zoom, Discord, Adobe Reader, the VLC media player, and even the LibreOffice suite are all now available in the Microsoft Store for people using the Windows 11 Insider Preview builds. Web apps like Wikipedia, Reddit, and Tumblr are also available. These PWAs look and work just like the regular websites but can easily be pinned to Start or the Taskbar and can display notification badges and a few other benefits that make them feel a bit more like desktop apps.

Microsoft also says it will allow other app stores into the Microsoft Store, starting with Amazon and the Epic Games Store. These will be available "over the next few months." (When support for Amazon's Android apps are added to Windows 11 sometime after the official launch, those apps will still be searchable from within the Microsoft Store itself.) If you don't want to (or can't) install Windows 11 on your PC, Microsoft says that the new Microsoft Store and the new apps in it will also be coming to Windows 10 "in the coming months." Windows 11's rollout officially begins on October 5.

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Chromebook demand is plummeting as the pandemic eases

ArsTechnica - Wed, 09/29/2021 - 8:54am
The 2020 Samsung Galaxy Chromebook, which had a 4K OLED display.

Enlarge / The 2020 Samsung Galaxy Chromebook, which had a 4K OLED display. (credit: Samsung)

A global deceleration of laptop sales is being linked in a new report from market research firm Trendforce to increasing vaccination rates and a corresponding decrease in remote work and remote learning. According to the findings, demand for Chromebooks slid by over 50 percent during one month since July. And notebook shipments for the remainder of the year are expected to be affected by the COVID-19 pandemic and the shifting demand from businesses.

Trendforce said that interest for ChromeOS-powered laptops within the last year had primarily been driven by remote learning. The analyst pointed to rising vaccination rates in North America, Europe, and Japan throughout the second half of 2021 as recently slowing demand for Chromebooks.

After being a “primary driver” of overall laptop shipments in the first half of 2021, Chromebook shipments dropped by over 50 percent during one month in the second half of the year. And because Chromebooks represent a “relatively high share” of HP's and Samsung’s overall laptop shipments, the OEMs’ shipments are predicted to fall by 10 to 20 percent from the first half of the year to the second half.

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Russia arrests cybersecurity expert on treason charge

ArsTechnica - Wed, 09/29/2021 - 7:47am
 Group-IB CEO and founder Ilya Sachkov speaks during a panel discussion with representatives of the IT industry at Innopolis' Popov Technopark.

Enlarge / KAZAN, RUSSIA - JULY 9, 2020: Group-IB CEO and founder Ilya Sachkov speaks during a panel discussion with representatives of the IT industry at Innopolis' Popov Technopark. (credit: Dmitry Astakhov | Getty Images)

The founder of one of Russia’s largest cybersecurity companies has been arrested on suspicion of state treason and will be held in a notorious prison run by the security services for the next two months, a Moscow court said on Wednesday.

The charges against Ilya Sachkov, founder of Group-IB, are classified and details of them were not immediately clear. State-run news agency Tass cited an anonymous source who said Sachkov denied passing on secret information to foreign intelligence services.

Group-IB, which specializes in preventing cybercrime and ransomware, confirmed that law enforcement raided its officers yesterday but said it did not know the reason for Sachkov’s arrest.

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Elizabeth Holmes urged employees to hide Theranos’ lab equipment from inspectors

ArsTechnica - Wed, 09/29/2021 - 6:17am
Elizabeth Holmes, founder and former CEO of Theranos, arrives for motion hearing on Monday, November 4, 2019, at the US District Courthouse in San Jose, California.

Enlarge / Elizabeth Holmes, founder and former CEO of Theranos, arrives for motion hearing on Monday, November 4, 2019, at the US District Courthouse in San Jose, California. (credit: Getty | Yichuan Cao)

A patient on blood thinners reported bruising and feeling off after a medication change following a Theranos test, the court heard yesterday in the criminal trial of company founder Elizabeth Holmes.

Her doctor had increased the dosing of her blood thinner in response to test results reported by Theranos. “I have not felt ‘right’ since the one increased dose and also experienced various skin bruising on my legs and arms almost immediately after the one dose increase,” she said in an email to Theranos. 

That complaint and other issues “raised serious and grave concerns for me about the accuracy of the testing process,” Dr. Adam Rosendorff, Theranos’ former lab director, told jurors in response to questioning by the prosecution. 

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A Virginia company has connected mobile phones directly to satellites

ArsTechnica - Wed, 09/29/2021 - 5:29am
Lynk's "Shannon" satellite launched into space in June on SpaceX's Transporter-2 flight.

Enlarge / Lynk's "Shannon" satellite launched into space in June on SpaceX's Transporter-2 flight. (credit: SpaceX)

A space startup says it has successfully demonstrated the ability to use ordinary, unmodified mobile telephones to connect to satellite Internet services.

The Virginia-based company, Lynk, sent its "Shannon" satellite into orbit three months ago as part of a rideshare mission on a Falcon 9 rocket. After some initial tests, the company said "hundreds" of mobile phones in the United States, United Kingdom, and the Bahamas were able to connect with the satellite as it passed overhead, as if it were a virtual cell phone tower in space.

"Basically, our satellite looks to your cell phone like a standard cell tower," said Charles Miller, the co-founder and chief executive of Lynk.

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Physicists may have cracked the case of “Zen” stones balanced on ice pedestals

ArsTechnica - Tue, 09/28/2021 - 7:25pm
A laboratory reproduction of the Zen stone phenomenon in a lyophilizer.

Enlarge / A laboratory reproduction of the Zen stone phenomenon in a lyophilizer. (credit: Nicolas Taberlet / Nicolas Plihon)

Visit the Small Sea of Lake Baikal in Russia during the winter and you'll likely see an unusual phenomenon: a flat rock balanced on a thin pedestal of ice, akin to stacking Zen stones common to Japanese gardens. The phenomenon is sometimes called a Baikal Zen formation. The typical explanation for how these formations occur is that the rock catches light (and heat) from the Sun and this melts the ice underneath until just a thin pedestal remains to support it. The water under the rock refreezes at night, and it has been suggested that wind may also be a factor.

Now, two French physicists believe they have solved the mystery of how these structures form, according to a new paper published in the Proceedings of the National Academy of Sciences—and their solution has nothing to do with the thermal conduction of the stone. Rather, they attribute the formation to a phenomenon known as sublimation, whereby snow or ice evaporates directly into vapor without passing through a water phase. Specifically, the shade provided by the stone hinders the sublimation rates of the surrounding ice in its vicinity, while the ice farther away sublimates at a faster rate.

Many similar formations occur naturally in nature, such as hoodoos (tall, spindly structures that form over millions of years within sedimentary rock), mushroom rocks or rock pedestals (the base has been eroded by strong dusty winds), and glacier tables (a large stone sitting precariously on top of a narrow pedestal of ice). But the underlying mechanisms by which they form can be very different. 

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Do Homeopathic Cures Work?

Discovery News Headlines - Fri, 11/27/2020 - 11:33am
Alternative medicine has proven tricky to study, and sometimes dangerous to patients. Doctors are divided as to whether or not it has any merit at all.
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