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Software used in judicial decisions meets its equal in random amateurs

3 hours 53 min ago

(credit: Adam Jones, Ph.D.)

In 2016, ProPublica caused a stir when it evaluated the performance of software that's used in criminal justice proceedings. The software, which is used to evaluate a defendant's chance of committing further crimes, turned out to produce different results when evaluating black people and caucasians.

The significance of that discrepancy is still the subject of some debate, but two Dartmouth College researchers have asked a more fundamental question: is the software any good? The answer they came up with is "not especially," as its performance could be matched by recruiting people on Mechanical Turk, or performing a simple analysis that only took two factors into account.

Software and bias

The software in question is called COMPAS, for Correctional Offender Management Profiling for Alternative Sanctions. It takes into account a wide variety of factors about defendants, and uses them to evaluate whether those individuals are likely to commit additional crimes and helps identify intervention options. COMPAS is heavily integrated into the judicial process (see this document from the California Department of Corrections for a sense of its importance). Perhaps most significantly, however, it is sometimes influential in determining sentencing, which can be based on the idea that people who are likely to commit additional crimes should be incarcerated longer.

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Categories: News

The first Chinese astronaut thought he was going to die

4 hours 31 min ago

Enlarge / Astronaut Yang Liwei lies in the re-entry capsule of Shenzhou-5 Spacecraft during a training on September 27, 2003 in Beijing, China. (credit: VCG via Getty Images)

Later this year, China will mark the 15th anniversary of its first human spaceflight. On October 15, 2003, Yang Liwei launched into space on a Long March 2F rocket. After making 14 orbits around Earth, Liwei returned to the planet as China received congratulations from countries around the world. It had succeeded where only the United States and Russia had before.

At the time, the secretive Chinese government released few technical details about the spaceflight. But apparently there were some serious problems, especially during the launch of the rocket. In a new interview with Xinhua, the official Chinese news media, Yang revealed that he experienced extreme vibrations between 30 and 40km above the ground.

"I thought I was going to die," Yang said. At the time, sitting in the seat of his cramped Shenzhou spacecraft, he recalled telling himself, "Hold on! Just hold on for a bit longer."

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Categories: News

Raw sprouts at Jimmy John’s linked to another outbreak—at least the 7th

6 hours 55 min ago

Enlarge / Jimmy John's Beach Club sandwich on seven grain bread with sprouts. Don't do it. (credit: Getty | The Washington Post)

On the 2018 list of “things that are a bad idea to shove in your face,” raw sprouts from Jimmy John’s may be up there—right behind Tide laundry pods.

The Centers for Disease Control and Prevention and the Food and Drug Administration announced late Friday that a multistate outbreak of Salmonella is linked to raw sprouts served at the sandwich chain’s restaurants in Wisconsin and Illinois. While sprouts in general are a well-established source of foodborne illnesses linked to many dozens of outbreaks in recent decades, Friday’s announcement marks at least the seventh time since 2008 that raw sprouts at Jimmy John’s specifically have caused outbreaks.

In response, Jimmy John’s on Friday ordered sprouts off the menu at all 2,727 of its restaurants. The company called the move a “precautionary measure.”

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Making tools gives crows a big food boost

Mon, 01/22/2018 - 18:00

Enlarge / A crow gets to work manufacturing a tool. (credit: Jolyon Troscianko)

Tool use among animals isn't common, but it is spread widely across our evolutionary tree. Critters from sea otters to cephalopods have been observed using tools in the wild. In most of these instances, however, the animal is simply using something that's found in its environment, rather than crafting a tool specifically for a task. Tool crafting has mostly been seen among primates.

Mostly, but not entirely. One major exception is the New Caledonian crow. To extract food from holes and crevices, these birds use twigs or stems that are found in their environment without modification. In other environments, however, they'll remove branches from plants and carefully strip parts of the plant to leave behind a hooked stick. The behavior takes over a minute, and the crows will typically carry the tool with them when they explore new sites, and they will sometimes store it for future use.

Understanding how this complex behavior came about in crows requires us to understand the evolutionary advantages that might be had from a good tool. A group of researchers, mostly from the University of St. Andrews, has now done just that: the researchers have quantified how tool manufacture influences food harvesting. The results show that the use of bird-crafted tools can increase food extraction by up to 12 times the rate the crows could achieve by using unmodified sticks.

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SpaceX gets good news from the Air Force on the Zuma mission

Mon, 01/22/2018 - 17:29

Enlarge / The launch of Zuma was pretty, but the aftermath has been anything but. (credit: SpaceX)

A little more than two weeks have passed since the apparent loss of the highly classified Zuma mission. Since then, SpaceX has publicly and privately stated that its Falcon 9 rocket performed nominally throughout the flight—with both its first and second stages firing as anticipated.

Now, the US Air Force seems to be backing the rocket company up. "Based on the data available, our team did not identify any information that would change SpaceX's Falcon 9 certification status," Lieutenant General John Thompson, commander of the Space and Missile Systems Center, told Bloomberg News. This qualified conclusion came after a preliminary review of data from the Zuma launch. That's according to Thompson, who said the Air Force will continue to review data from all launches.

However tentative, this statement buttresses the efforts by SpaceX to say that, from its perspective, the mission was a success. The statement also adds to the concerns of Northrop Grumman, which built the Zuma payload and the adapter that connected it to the Falcon 9 rocket. Northrop Grumman was also responsible for separating after the second stage of the Zuma rocket reached space. The aerospace veteran has yet to publicly comment on specifics of the Zuma mission since the launch.

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Rocket Lab makes it into orbit, nears commercial operations

Mon, 01/22/2018 - 09:15

Rocket Lab

Last Sunday afternoon in New Zealand, Rocket Lab successfully made it into orbit on just the company's second flight attempt. Launching from a new spaceport that juts into the South Pacific Ocean, the Electron rocket climbed into orbit and deployed its customer payloads at 8 minutes and 31 seconds after lifting off.

“Today marks the beginning of a new era in commercial access to space. We’re thrilled to reach this milestone so quickly after our first test launch,” Rocket Lab CEO and founder Peter Beck said in a statement. “Our incredibly dedicated and talented team have worked tirelessly to develop, build and launch Electron. I’m immensely proud of what they have achieved today.”

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For new form of male birth control, scientists turn to poison arrows

Sun, 01/21/2018 - 11:00

Enlarge / Aim carefully. (credit: Getty | Brian Seed )

According to scientists, a poison arrow in the quiver may let loose a very sticky nether-region massacre.

The poison in question has spattered from the tips of African weapons for centuries, rubbing out wild beasts and halting the hearts of warriors. But, according to a study in the Journal of Medicinal Chemistry, a crotch shot of an ancient toxin called “ouabain” can also take out sperm. By tweaking the poison’s chemical backbone (or scaffold), it can selectively paralyze trouser troops and prevent them from storming eggs, the authors report.

The study’s authors, led by Shameem Sultana Syeda of the University of Minnesota, are optimistic that, with further aiming, the poison’s progeny could one day strike as a safe, reversible male contraceptive.

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A randomly generated, totally novel enzyme rescues mutant bacteria

Sat, 01/20/2018 - 15:30

Enlarge / Colorized scanning electron micrograph of Escherichia coli (E. coli), grown in culture and adhered to a cover slip. (credit: NIAID / Flickr)

Proteins are chains of amino acids, and each link in the chain can hold any one of the 20 amino acids that life relies on. If you were to pick each link at random, the number of possible proteins ends up reaching astronomical levels pretty fast.

So how does life ever end up evolving entirely new genes? One lab has been answering that question by making its own proteins from scratch.

Way back in 2016, the same lab figured out that new, random proteins can perform essential functions. And those new proteins were really new. They were generated by scientists who made amino acid sequences at random and then kept any that folded into the stable helical structures commonly found in proteins. These proteins were then screened to see if any could rescue E. coli that were missing a gene essential to survival.

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Can we zero-in on Earth’s sensitivity to CO₂?

Fri, 01/19/2018 - 14:25

Enlarge (credit: Kristin Andrus)

If it were easy to pin down the exact value for our planet’s sensitivity to greenhouse gas emission, it would have been done a long time ago—and you wouldn’t be reading yet another news story about it. It's not like we have no idea how sensitive the climate is. The range of possible values that scientists have been able to narrow it down to only spans from “climate change is very bad news” to “climate change is extremely bad news.”

But the difference between “very bad” and “extremely bad” is pretty important, so climate scientists aren’t throwing up their hands any time soon—as two new studies published this week show.

There are several basic strategies available for calculating the climate's sensitivity. These range from studying climate changes in the distant past to building and evaluating climate models to analyzing the warming over the last century or so. Each strategy has pros and cons. A handful of studies looking at the last century made waves a few years ago for yielding oddly lowball estimates of the impact of CO2 on warming, for example. Later studies have found problems that push those estimates upward when corrected, but one of this week’s studies demonstrates that the entire strategy is inherently problematic.

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Categories: News

The global state of science

Fri, 01/19/2018 - 12:59

Enlarge (credit: Oak Ridge National Lab)

By law, the National Science Foundation is required to do a biennial evaluation of the state of science research and innovation. This is one of the years it's due, and the NSF has gotten its Science and Engineering Indicators report ready for delivery to Congress and the president. The report is generally optimistic, finding significant funding for science and a strong return on that investment in terms of jobs and industries. But it does highlight how the global focus is shifting, with China and South Korea making massive investments in research and technology.

Science isn't a monolithic endeavor, so there's no way to create a single measure that captures global scientific progress. Instead, the NSF looked at 42 different indicators that track things like research funding, business investments, training of scientists, and more. All of these measures were evaluated for the globe, in order to put the US' scientific activity in perspective.

Show me the money

Overall, science funding is on a good trajectory. In 2005, global R&D spending was just under a trillion dollars; by 2015, it had cleared $2 trillion. In total, 75 percent of that is spent in 10 nations; in order of spending, these are the United States, China, Japan, Germany, South Korea, France, India, and the United Kingdom. The US alone spends about $500 billion. China, which was at roughly $100 billion a decade ago, has now cleared $400 billion.

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The Zuma failure has emboldened critics of SpaceX

Fri, 01/19/2018 - 10:25

Enlarge / The Zuma mission launched on Jan. 7 from Florida. (credit: SpaceX)

The space community has not learned much about the apparent loss of the Zuma payload launched by SpaceX on January 7, but the mystery has had one clear after effect: critics of SpaceX, including several far-right publications, have weaponized the failure of a national security satellite in their continued stream of attacks on the company.

For example The Federalist, a publication that defended the dating habits of Alabama Judge Roy Moore in his Senate campaign, opined about the accident, "It is concerning, to say the least, that American taxpayers have become the guinea pigs who will bear the risks and the costs before a final determination can be made." The conservative Washington Times also published a critical piece, noting that, "Taxpayers are tired of getting ripped off."

These articles were written by individuals with little apparent knowledge about the aerospace industry. The Federalist author lists, among his qualifications, that he "helped the 2014 freshmen Republican class to set up offices." The Times author notes on his LinkedIn profile that he is a "professional coalition builder."

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Wind with batteries? Build it quickly and it could cost $21/MWh in Colorado

Fri, 01/19/2018 - 08:35

Enlarge / A couple of wind turbines, part of the Cedar Point Wind Energy Project in Limon, Colorado. (credit: Getty Images)

Proposals for renewable electricity generation in Colorado are coming in cheap, like, $21/MWh-cheap for wind and battery storage. Though there are a few caveats to those numbers, federal incentives and quickly falling costs are combining to make once-quirky renewable projects into major contenders in an industry where fossil fuels have comfortably dominated since the 19th century.

Early last year, Colorado energy provider Xcel Energy requested proposals for new electricity generation. Specifically, the company needed 450 megawatts of additional generation to meet future demand. In a separate request called the Colorado Energy Plan, Xcel said (PDF) it would consider replacing two coal plants providing 660MW of capacity with "hundreds of megawatts of new wind and solar as well as some natural gas-fired resources" if new resources could be found cheaper than what those coal plants cost to operate (including costs to shut down the plants early).

By late November, energy companies had submitted their best offers. Although exact details of the offers aren’t available yet, Xcel Colorado was required to make public a summary of the proposals (PDF) in the month after the bids were submitted.

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NASA has pulled Jeanette Epps just months before her first flight

Thu, 01/18/2018 - 19:00

Enlarge / Jeanette Epps, left, served as a back-up crew member to Expedition 54 to the space station. (credit: NASA)

NASA issued a short news release on Thursday evening stating that Jeanette Epps will not be a part of the International Space Station crew set to launch in June. (That flight would launch from Kazakhstan aboard a Soyuz rocket.) The release gave no reason why Epps was pulled from the flight.

In a response to a request for more information, Johnson Space Center spokeswoman Brandi Dean told Ars, "A number of factors are considered when making flight assignments. However, these decisions are personnel matters for which NASA doesn’t provide information."

According to NASA, Epps had returned to the active Astronaut Corps at the space center to assume duties in the astronaut office. She will be considered for assignment to future missions. Had she flown this year, Epps would have become the first African-American astronaut to live as a crew member aboard the International Space Station. Only three other African American women have flown into space. Epps' assignment in January 2017 garnered a fair amount of favorable publicity for the space agency.

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Peeved by price gouging and shortages, hospitals will now make their own drugs

Thu, 01/18/2018 - 16:28

Enlarge / Former pharmaceutical executive Martin Shkreli. Jail for him, competition for his kind. (credit: Getty | Drew Angerer )

For four of the country’s largest hospital systems, enough is enough.

Sick of drug companies’ eye-popping price hikes and ridiculous shortages, the feisty hospital systems announced Wednesday that they’ve banded together and formed an unnamed non-profit to make their own steady supply of affordable generic medicines.

The leading hospital system, Intermountain Healthcare, released a statement explaining:

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Planet finally stops setting warmest year records; 2017 merely finishes Top 3

Thu, 01/18/2018 - 12:03

Enlarge / The results from NASA's dataset (showing temperature above the 1951-1980 average), which ranks 2017 as the 2nd warmest year on record. (credit: NASA)

Last year had its fair share of attention-grabbing natural disasters, so you can be forgiven for not keeping an eye on the global average temperature as the months rolled by. But NASA, the National Oceanic and Atmospheric Administration (NOAA), and the UK Met Office all announced their final tally today: 2017 ranks as the second or third warmest year on record, depending on which dataset you ask.

In the NASA dataset, 2017 comes in a few hundredths of a degree Celsius above third-place 2015, while NOAA puts 2015 a touch above 2017. The UK Met Office dataset also ranks 2017 in third. The datasets use slightly different methods, including different approaches to handling the polar regions, where weather stations are sparse.

It turns out that the cold weather in the eastern United States around the holiday season was not indicative of what was happening on the rest of the planet, much less for the rest of the year. President Donald Trump may have been tweeting that "we could use a little bit of that good old Global Warming," but he was doing so during an exceedingly warm year.

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Russia now looking to sell its prized rocket engines to China

Thu, 01/18/2018 - 09:30

Enlarge / The Atlas V rocket is powered by a single RD-180 rocket engine. (credit: United Launch Alliance)

Ever since the Crimean crisis in 2014—precipitated by Russia's annexation of the Ukrainian-held peninsula—Congress has increased pressure on the US aerospace industry to end its use of Russian-made rocket engines. In particular, legislators want United Launch Alliance to stop using the RD-180 engine in its Atlas V launch vehicle. This booster, with a 100 percent mission success rate, launches many of America's national security payloads.

As United Launch Alliance plans to transition to US-made engines early next decade, and with other US rockets already flying or soon coming online, the Russian RD-180 manufacturers are looking to other markets. In doing so, they've found willing buyers in China, although this has come with some concerns.

Even though the rocket engine technology behind the RD-180 is 40 years old, it remains one of the highest performing engines in the world, with a near-perfect service record. With 860,000 pounds of thrust (about 3.8MN), the RD-180 also happens to be three times more powerful than any Chinese rocket engine.

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Scientists racing to save vital medical isotopes imperiled by shabby reactors

Wed, 01/17/2018 - 18:10

Enlarge / A dose of Tc-99m to be used in an upcoming scan. (credit: Getty | Rene Johnston)

There’s a mad dash for a vital radioactive isotope that’s used in about 50,000 medical procedures every day in the US, including spotting deadly cancers and looming heart problems. Currently, access to it hinges on a shaky supply chain and a handful of aging nuclear reactors in foreign countries. But federal regulators and a few US companies are pushing hard and spending millions to produce it domestically and shore up access, Kaiser Health News reports.

The isotope, molybdenum-99 (Mo-99), decays to the short-lived Technetium-99m (Tc-99m) and other isotopes, which are used as radiotracers in medical imaging. Injected into patients, the isotopes spotlight how the heart is pumping, what parts of the brain are active, or if tumors are forming in bones.

But, to get to those useful endpoints, Mo-99 has to wind through a fraught journey. According to KHN, most Mo-99 in the US is made by irradiating Cold War-era uranium from America’s nuclear stockpile. The US Department of Energy’s National Nuclear Security Administration secretly ships it to aging reactors abroad. The reactors—and five subsequent processing plants—are in Australia, Canada, Europe (Netherlands, Belgium, Poland, and the Czech Republic), and South Africa, according to a 2016 report by The National Academies of Sciences, Engineering and Medicine. Private companies then rent irradiation time at the reactors, send the resulting medley of isotopes to processing plants, book the final Mo-99 on commercial flights back to the US, and distribute it to hospitals and pharmacies.

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Immigrant-friendly policies make most whites feel welcomed, too

Wed, 01/17/2018 - 14:01

Enlarge (credit: National Park Service)

Immigration policy in the US has grown increasingly contentious, seemingly pitting different communities and ideologies against each other. But a new study suggests that a large majority of Americans appreciate a welcoming policy toward immigrants. Only a specific minority—white conservatives—generally feels otherwise. And the effect isn't limited to policy, as it influenced whether citizens felt welcome in the place that they lived.

The research, performed by a collaboration of US-based researchers, focused on New Mexico and Arizona. These states have similar demographics but radically different policies toward immigrants. Arizona has state policies that encourage police to check the immigration status of people they encounter; controversial Arizona sheriff Joe Arpaio ended up in trouble with the court system in part due to how aggressively he pursued this program. New Mexico, by contrast, will provide state IDs and tuition benefits to immigrants regardless of their documentation status.

The researchers reasoned that these states would provide a reasonable test as to how immigration policies align with the feelings of the public. So they surveyed nearly 2,000 residents of the two states, including immigrants, naturalized US citizens, and people born in the US, focusing on the states' Caucasian and Hispanic populations.

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NASA’s internal schedule for the commercial crew program is pretty grim

Wed, 01/17/2018 - 13:51

Enlarge / Despite her smiles here, NASA's commercial crew program manager has concerns about schedules for Boeing and SpaceX. (credit: NASA)

Publicly, both Boeing and SpaceX maintain that they will fly demonstration missions by the end of this year that carry astronauts to the International Space Station. This would put them on course to become certified for "operational" missions to the station in early 2019, to ensure NASA's access to the orbiting laboratory.

On Wednesday, during a congressional hearing, representatives from both companies reiterated this position. "We have high confidence in our plan," Boeing's commercial crew program manager, John Mulholland, said. SpaceX Vice President Hans Koenigsmann said his company would be ready, too.

However their testimony before the US House Subcommittee on Space was undercut by the release of a report Wednesday by the US Government Accountability Office. The lead author of that report, Christina Chaplain, told Congress during the same hearing that she anticipated these certification dates would be much later. For SpaceX, operational flights to the station were unlikely before December, 2019, and Boeing unlikely before February, 2020, Chaplain said.

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Meteor lights up southern Michigan

Wed, 01/17/2018 - 13:38

Enlarge / That's no moon!

Early last night local time, a meteor rocketed through the skies of southern Michigan, giving local residents a dramatic (if brief) light show. It also generated an imperceptible thump, as the US Geological Survey confirmed that there was a coincident magnitude 2.0 earthquake.

The American Meteor Society has collected more than 350 eyewitness accounts, which ranged from western Pennsylvania out to Illinois and Wisconsin. They were heavily concentrated over southern Michigan, notably around the Detroit area. A number of people have also posted videos of the fireball online; one of the better compilations is below.

A compilation of several videos from Syracuse.com.

The American Meteor Society estimates that the rock was relatively slow-moving at a sedate 45,000km an hour. Combined with its production of a large fireball, the researchers conclude it was probably a big rock. NASA's meteorwatch Facebook page largely agrees and suggests that this probably means that pieces of the rock made it to Earth. If you were on the flight path, you might want to check your yard.

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