You are here

Ars Science

Subscribe to Ars Science feed Ars Science
Serving the Technologist for more than a decade. IT news, reviews, and analysis.
Updated: 1 min 38 sec ago

Russian embassy trolls US launch industry after new rocket engine sale

Wed, 08/01/2018 - 13:44

Enlarge / An Atlas V rocket lifts off in 2016, powered by a single RD-180 engine and solid rocket boosters. (credit: United Launch Alliance)

According to Russian publications, the Russia-based rocket propulsion company Energomash has signed a deal to sell six more RD-180 rocket engines to United Launch Alliance in 2020. These six engines will allow for six additional flights of the Atlas V rocket, which flies national security payloads and science missions for the US government. Soon, the rocket will also fly Boeing's crewed Starliner spacecraft into orbit.

NASA has understandably made a big deal out of its commercial crew program through which it is paying Boeing and SpaceX to develop spacecraft that will allow astronauts to launch to the International Space Station from Florida. Since the 2011 retirement of the space shuttle, NASA has gotten its people into space aboard Russian rockets launching from Kazakhstan.

Seizing upon this announcement, the Russian embassy in Washington, DC, evidently felt the need to troll United Launch Alliance, the US military, and NASA on Twitter, saying, "Russian rocket engines to continue launching America into space."

Read 6 remaining paragraphs | Comments

Categories: News

661Tbps through a single optical fiber: The mind boggles

Wed, 08/01/2018 - 12:40

Enlarge (credit: NOAA)

Society has an insatiable desire for data. In fact, it is rather astonishing to think that average Internet traffic is several hundred terabits per second and consumes about eight percent of our electricity production. All of that for instant cat videos—and our desire for new cat videos is apparently insatiable, driving the need for more capacity and even more energy.

It would, however, be nice to scale capacity without energy requirements continuing to grow at the same rate. In a step toward achieving this goal, researchers have managed to encode an insane amount of information into the light of a single laser.

The problem with scaling bandwidth and power comes down to lasers and their inefficiency. A good laser is about 30-percent efficient. A typical telecommunications laser might emit 20mW, so that's at least 70mW for each laser (the amplifiers consume even more energy). To pack more data into a single optical fiber, the data is divided across different colors of light, called wavelength division multiplexing. Unfortunately, each color requires its own laser, meaning the energy cost increases with bandwidth. 

Read 10 remaining paragraphs | Comments

Categories: News

Climate change brings the UK’s hidden past to the surface

Wed, 08/01/2018 - 12:16

Enlarge / Crop marks trace the circular boundaries of a prehistoric settlement, with the faint outlines of a Roman villa inside. (credit: Crown Copyright: Royal Commission on the Ancient and Historical Monuments of Wales)

In southern Wales’ Vale of Glamorgan, archaeologists flying over a prehistoric settlement they had previously studied got a surprise: the ghostly outline of a Roman villa on the ground inside the older settlement’s boundaries. “We know of Roman villas built within prehistoric settlements elsewhere,” the Royal Commission on the Ancient and Historical Monuments of Wales wrote in a published statement, “but this is a new example.”

Other new discoveries have been popping up across the British Isles over the last few weeks. An atmospheric high pressure system parked over Scandinavia has made the weather hotter and drier than usual across much of northern Europe. The resultant drought creates the perfect conditions for what archaeologists call “crop marks.”

Stone walls or foundations buried beneath a modern landscape tend to absorb more heat than the soil around them. The heat that those buried stones radiate can bake the soil above to a lighter color, so the outlines of ancient buildings and fences show up on the parched surface of modern lawns and fields. The shapes of centuries-old garden beds and paths have emerged from the lawns of several old estates in the UK. At Gawthorpe Hall in Lancashire, the shapes included some details no one had seen before that may be the ruins of even older gardens, dating back to the reign of Elizabeth I.

Read 14 remaining paragraphs | Comments

Categories: News

Work begins on rocket engines for SLS flights a decade from now

Wed, 08/01/2018 - 09:41

Enlarge / NASA conducts a test of an RS-25 rocket engine on the A-1 Test Stand at Stennis Space Center. (credit: NASA)

One of the primary criticisms of NASA's Space Launch System is that the program was created to save jobs at key agency contractors that otherwise would have been lost following the end of the space shuttle program. The large, new rocket includes several heritage components from the shuttle, including its main engines.

When the space shuttle program ended in 2011, NASA had 15 of the reusable main engines left over and has since built one more from spare parts. Because the expendable SLS rocket will use four engines in its core stage, this means NASA presently has enough for the first four flights of the SLS rocket.

NASA will therefore eventually need more engines for the SLS rocket—assuming the rocket flies more than a handful of flights— and so the agency awarded Aerojet Rocketdyne a $1.16 billion contract in 2016 to restart production of a modified version of the space shuttle main engine, known as the RS-25. In addition to this, the space agency placed an order for six "flight" engines, bringing the total value of the contract to $1.5 billion.

Read 6 remaining paragraphs | Comments

Categories: News

Find shows 4,000-year-old trade routes stretched from Carolinas to Great Lakes

Tue, 07/31/2018 - 11:45

Enlarge / This copper band was interred with the cremated remains of at least seven people. (credit: American Museum of Natural History)

Cremated remains and a broken copper band in a 4,000-year-old settlement on a barrier island off the coast of Georgia suggest that trade networks in ancient North America linked people from the Great Lakes to the southeastern coast. And it wasn't just about exchanging goods; the far-flung connections created shared culture.

Widespread trade networks once linked communities in northeastern US with those around the Great Lakes and the Ohio River Valley and extended south to the Tennessee River Valley. Around 5,000 years ago, hunter-gatherer societies in eastern North America started to become more settled, and their populations started to grow. As these communities grew, they also developed long-distance social and economic connections with other communities.

In the archaeological record, we can only really see evidence for the exchange of goods, especially shells, beads, raw stone for working into tools, and copper. But those are probably just the tangible pieces of a more complex set of relationships that may have included political marriages to cement alliances and large ritual gatherings to bring people together and demonstrate wealth, power, and status.

Read 19 remaining paragraphs | Comments

Categories: News

Sorry, Elon: Nuking Mars’ icecaps won’t geoengineer planet

Tue, 07/31/2018 - 10:35

Enlarge / It's a lot of ice, but not enough to make an atmosphere. (credit: NASA/JPL-Caltech/MSSS)

Mars clearly had a warm and wet past, a time when streams, lakes, and even an ocean were present on its surface. Currently, however, most water on the planet appears to be locked in its icy poles, and the atmosphere is so thin that water would quickly evaporate even if temperatures were held at Earth-like levels. But could we go back to the future? Is there enough material on Mars to form a dense atmosphere filled with enough greenhouse gasses to keep things warm enough for liquid water?

SpaceX CEO Elon Musk attracted a bit of attention when he suggested that we could get there simply by nuking Mars' poles, liberating the ice (both water and carbon dioxide ices) into the atmosphere. When asked about the prospects for the plan, a scientist said, "Whether it would really work, I don't think anyone has worked up the physics in enough detail to say it would." Now, a couple of planetary scientists have accepted the challenge of working up the physics, and they have bad news for Musk.

Greenhouse and pressure

The researchers, Bruce Jakosky and Christopher Edwards, focus on two significant questions. The first is whether we can put enough gasses back into the atmosphere to create an Earth-like air pressure so that people who need to do something on the surface don't need to wear bulky suits to isolate themselves from the environment. The second is whether we can warm the surface enough so that liquid water could persist on it.

Read 13 remaining paragraphs | Comments

Categories: News

Don’t try to rejuvenate your vagina, FDA warns after scolding companies

Tue, 07/31/2018 - 07:15

Enlarge / Food and Drug Administration Commissioner Scott Gottleib is not amused. (credit: Getty | Chip Somodevilla )

The Food and Drug Administration is cracking down on companies “deceptively” marketing unproven “vaginal rejuvenation” devices and treatments that have been reported to cause serious burns, scars, and chronic pain, the agency announced on Monday, July 30.

In addition to warning consumers, the FDA revealed that it has taken action, sending warning letters to seven companies marketing “energy-based” devices that are being used outside of their cleared or approved intended uses. Some of the devices, which are commonly radiofrequency- or laser-based, have legit uses such as removing warts or pre-cancerous vaginal or cervical tissue.

But, the agency notes, there’s no proof that these devices are effective for any of the “rejuvenating” procedures companies claim and some celebrities promote. These include empowering-sounding treatments that claim to tighten tissue, relieve pain, and boost sexual pleasure. More specifically, the companies collectively claim that the devices are able to treat vaginal “laxity,” pain during urination or intercourse, decreased sexual sensation, and vaginal dryness, itching, or atrophy. Some of these issues are symptoms related to menopause, urinary incontinence, or sexual function issues.

Read 6 remaining paragraphs | Comments

Categories: News

A new report questions “viability” of plan to privatize the space station

Mon, 07/30/2018 - 16:05

Enlarge / The International Space Station is an important test bed for microgravity research. But it's also very costly. (credit: NASA)

A new report from the space agency's inspector general concludes that NASA has no easy choice when it comes to the future of the massive International Space Station that orbits about 400km above the Earth. The station, which has been continually inhabited by humans for nearly two decades, is presently the only destination in outer space for astronauts and cosmonauts to visit.

Recently, the White House announced that it wanted to end direct NASA funding for the space station in the year 2025 and transfer operations to the private sector. Key Senators who oversee NASA's activities have pushed back against this idea in a bipartisan way, saying that the station should be funded through 2028 in order to complete its mission of scientific research. That extension would also help development and testing of new technologies needed for deep space exploration by humans—such as toilets that don't break every six months.

In the report published Monday, NASA Inspector General Paul Martin found that both of these choices have some significant downsides. "Each of the options for transitioning or retiring the ISS present NASA with distinct challenges and associated cost," the report states.

Read 9 remaining paragraphs | Comments

Categories: News

Vaccine-refusing community drove outbreak that cost $395K, sickened babies

Mon, 07/30/2018 - 15:56

Enlarge / A child gets a measles vaccine. (credit: Getty | BSIP)

A 2013 measles outbreak rooted in a vaccine-refusing community in Brooklyn, New York cost the city’s health department an estimated $394,448, requiring 87 employees to collectively spend more than 10,000 hours on outbreak response and control, according to an analysis published Monday in JAMA Pediatrics.

During the outbreak, which spanned March through July, health workers quickly mobilized to track down more than 3,300 people exposed to the highly contagious, potentially life-threatening virus. Workers then determined the vaccination status of those exposed and doled out prophylactic treatments or vaccines to those who would take them. To get the word out about the health threat, workers contacted local doctors’ offices, schools, and daycares. They also placed announcements in local newspapers, set up a telephone hotline, and held community briefings on the situation.

Almost a third of the employees involved in the response were working outside of their job descriptions, diverting resources from other critical public health activities. The cost estimate combined a conservative assessment of employee compensation ($332,000) and supply costs, such as lab testing and advertising ($62,000).

Read 9 remaining paragraphs | Comments

Categories: News

Neural network implemented with light instead of electrons

Sun, 07/29/2018 - 10:00

Enlarge / Each of these layers shapes the light that reaches the one behind it, performing calculations in the process. (credit: Ozcan Lab, UCLA)

Neural networks have a reputation for being computationally expensive. But only the training portion of things really stresses most computer hardware, since it involves regular evaluations of performance and constant trips back and forth to memory to tweak the connections among its artificial neurons. Using a trained neural network, in contrast, is a much simpler process, one that isn't nearly as computationally complex. In fact, the training and execution stages can be performed on completely different hardware.

And there seems to be a fair bit of flexibility in the hardware that can be used for either of these two processes. For example, it's possible to train neural networks using a specialized form of memory called a memristor or execute trained neural networks using custom silicon chips. Now, researchers at UCLA have done something a bit more radical. After training a neural network using traditional computing hardware, they 3D printed a set of panels that manipulated light in a way that was equivalent to processing information using the neural network. In the end, they got performance at the speed of light—though with somewhat reduced accuracy compared to more traditional hardware.

Lighten up

So how do you implement a neural network using light? To understand that, you have to understand the structure of a deep-learning neural network. In each layer, signals from an earlier one (or the input from a source) are processed by "neurons," which then take the results and forward signals on to neurons in the next layer. Which neurons they send it to and how strong a signal they pass on are determined by the training they've undergone.

Read 10 remaining paragraphs | Comments

Categories: News

Why do so many moms die and suffer in the US? Stupid negligence

Fri, 07/27/2018 - 14:38

Enlarge / Pregnant woman in a delivery room having her blood pressure monitored. (credit: Getty | BSIP)

The US has a shameful record when it comes to caring for its moms. As Ars has reported before, the rate of women dying during pregnancy or childbirth is higher—much higher—than in any other developed country. By some estimates, mothers die in the US at a rate six-times that seen in Italy and three-times the rate in the UK, for instance. And of those that survive, tens of thousands suffer devastating injuries and near-death experiences each year.

It’s hard to compare such stats with precision, of course, because official numbers don’t exist in this country. US hospitals either won’t reveal or don’t determine rates of maternal complications, and the country as a whole simply doesn’t monitor the deaths consistently or accurately. The US hasn’t reported an official maternal death rate since 2007—a situation health experts have called an “international embarrassment.”

Nevertheless, health researchers, hospital organizations, policy makers, and state task forces have been working to understand and reverse the horrific numbers—often doing so with limited resources and reliance on volunteers. While reports have offered glimpses of the problem, a new investigation by USA Today provides one of the sharpest pictures yet.

Read 9 remaining paragraphs | Comments

Categories: News

After 25 years, military told to move from “expendable” to “reusable” rockets

Fri, 07/27/2018 - 10:45

Enlarge / Congress has recognized the promise of reusable rockets. (credit: SpaceX)

Less than a year and a half has passed since SpaceX first flew a used first stage of a Falcon 9 rocket, but this achievement has already shaken up the glacial process of lawmaking and military budgeting. The final version of the defense budget bill for fiscal year 2019 will make both a symbolic and a significant policy change when it comes to reusable rockets.

The conference report from the US House and Senate calls for the Evolved Expendable Launch Vehicle program of the Department of Defense, commonly known as the EELV program, to be named the "National Security Space Launch program" as of March 1, 2019. No longer will the military rely solely on expendable rockets.

Moreover, the report says the US Air Force must consider both expendable and reusable launch vehicles as part of its solicitation for military launch contracts, and in the event that a reusable launch vehicle is available but not selected, report back to Congress with the reason why. The US House has already agreed to the conference report, and it should be taken up in the Senate next week. After that, it will need the president's signature to become law.

Read 9 remaining paragraphs | Comments

Categories: News

It’s too soon to tell if the Great Barrier Reef’s bleaching was a catastrophe

Fri, 07/27/2018 - 10:15

Enlarge / This southern reef escaped bleaching, but other areas were not so lucky. (credit: Rick Stuart-Smith, Reef Life Survey)

In a heat wave, humans sweat and try to avoid heat exhaustion. But in a coral reef, a wave of warm ocean temperatures can trigger a very different response from ours. Corals host single-celled, photosynthetic symbiotes called zooxanthellae that provide food in exchange for shelter. During a heat wave, the corals are forced to kick the zooxanthellae out (lest the coral be poisoned by their stressed excretions), losing the corals' source of food as well as the majority of their color—hence the name “coral bleaching”.

If the warm water stays too long, the corals starve and leave behind lifeless carbonate skeletons. Young corals may repopulate the area in time, although algae will often claim the abandoned structures in the meanwhile.

The last few years have hit Australia’s Great Barrier Reef pretty hard, with a massive bleaching event in 2016 and persistently elevated temperatures giving no respite—part of a trend in a warming climate. A team led by the University of Tasmania’s Rick Stuart-Smith hit the water almost a year after the bleaching to get a first look at the recovery process.

Read 8 remaining paragraphs | Comments

Categories: News

Ebola mysteriously hid in a woman for more than a year before spreading

Fri, 07/27/2018 - 08:21

Enlarge / A family watches as a burial team lowers their loved one into a grave at the US-built cemetery for "safe burials" on January 27, 2015 in Disco Hill, Liberia, amid an Ebola epidemic. (credit: Getty | John Moore)

The World Health Organization on Tuesday declared the official end of the latest outbreak of Ebola in the Democratic Republic of the Congo, which tallied 54 cases, including 33 deaths. But a study published this week in the Lancet Infectious Diseases highlights just how tenuous such declarations can be when it comes to Ebola.

The study, led by researchers at the Centers for Disease Control and Prevention, traced a puzzling cluster of Ebola cases in Liberia to a mother who appeared to have had a stealthy, undiagnosed infection for more than a year. The cluster came to light when the woman’s 15-year-old son arrived at a hospital in Monrovia on November 17, 2015—more than two months after the country had been declared free of the disease in the wake of a massive outbreak that began in 2013. The woman’s husband and another of their four sons, an eight-year-old, subsequently tested positive for the virus.

Based on extensive epidemiological tracking, blood work, and viral genetic data, the researchers concluded that the woman likely picked up an Ebola infection in July of 2014. At the time, she was pregnant and caring for her brother, a nurse’s aide at a local clinic, who had come down with an illness after helping to treat an undiagnosed patient with symptoms consistent with Ebola. Her brother’s supervisor, wife, and seven-year-old son also fell ill.

Read 12 remaining paragraphs | Comments

Categories: News

Rocket Report: SpaceX doubles up, European resistance, condensed Kármán

Fri, 07/27/2018 - 07:00

Enlarge / The Rocket Report is published weekly. (credit: Arianespace/Aurich Lawson)

Welcome to Edition 1.10 of the Rocket Report! This week, we have lots of action from the European Space Agency's launch site in South America, multiple launches by SpaceX as it goes for two dozen flights this year, and updates on all of the big new rockets that may launch in 2020. Or, maybe not.

As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

A southern island in the Azores may make for a good spaceport. According to a new study commissioned by the European Space Agency, the mid-Atlantic island of Santa Maria, in the Azores, is suitable for the development of a spaceport for small rocket launchers, the local newspaper Público reported. Santa Maria already hosts an ESA ground tracking station for launches from Kourou, in French Guiana.

Read 24 remaining paragraphs | Comments

Categories: News

Neanderthals used stone hand axes to strike a light

Thu, 07/26/2018 - 16:40

Enlarge / Neanderthals used stone hand axes, or bifaces, like these, along with chunks of pyrite, to light fires. (credit: Johnbod via Wikimedia Commons)

We know Neanderthals used fire because we have burned animal bones from several archaeological sites along with evidence that Neanderthals collected manganese dioxide, a black mineral powder the helps lower the combustion temperature of wood. But archaeologists haven't been convinced that Neanderthals kindled the fires themselves.

It's been suggested that the first humans to use fire happened to make use of convenient natural fires, such as those sparked by lightning strikes, and only learned how to set things on fire themselves later. Without clear evidence of firestarting, there's no way to demonstrate that Neanderthal technology had progressed to that stage by the time the last of them died off.

"While it is generally assumed that modern humans were proficient fire-markers, some researchers doubt Neanderthals knew how to make fire despite evidence that they used fire regularly," wrote Leiden University archaeologist Andrew Sorensen and his colleagues in a new paper. "Only by identifying the tools used to make fire can we know if Neanderthals possessed this skill."

Read 17 remaining paragraphs | Comments

Categories: News

Virgin’s Unity spaceship sets a new altitude record of 52 kilometers

Thu, 07/26/2018 - 15:10

Virgin Galactic

Virgin Galactic has been saying for some time that it will reach outer space this year, and on Thursday it came the closest it has ever gotten. During the third powered flight of the VSS Unity vehicle, the spacecraft reached an altitude of 52km (32.3 miles), just over halfway toward the Kármán line, which generally is regarded as the beginning of space. This is the first time that Virgin Galactic has flown into the mesosphere.

The company also released a few other details about the flight, noting that the spacecraft was released from its carrier aircraft at 14.2km, that its engine burned for 42 seconds, and that the vehicle reached a maximum speed of Mach 2.7. Pilots Dave Mackay and Mike “Sooch” Masucci flew the Unity vehicle on Wednesday morning from the Mojave Air & Space Port.

Read 4 remaining paragraphs | Comments

Categories: News

British man unwittingly gave Russian nerve agent to his girlfriend as a gift

Thu, 07/26/2018 - 09:30

Enlarge / SALISBURY, ENGLAND - JULY 06: Work is carried out behind a police cordon in front of John Baker House Sanctuary Supported Living after a major incident was declared when a man and woman were exposed to the Novichok nerve agent. (credit: Getty | Jack Taylor)

British officials announced Wednesday they are investigating whether attackers dropped multiple, hidden stashes of the deadly Russian Novichok nerve agent around an English town as part of a plot to poison former Russian double agent Sergei Skripal and his daughter Yulia in March.

The Skripals were found March 4, slumped on a bench in Sergei’s home town of Salisbury, England. The two had been poisoned by the military-grade chemical weapon, but later regained consciousness and are recovering in an undisclosed location. Britain and its NATO allies united to blame Russia for the attack.

The new revelation that there could be more Novichok in the otherwise quiet town comes as a man poisoned by the same agent several weeks ago near Salisbury told the press that he came across the nerve agent in a branded, cellophane-wrapped box containing a bottle he thought was full of perfume. The victim in that case, Charlie Rowley, 45, didn’t reveal—or remember—exactly where he had found the box. He said that on June 20 he gave it as a gift to his girlfriend, Dawn Sturgess, who recognized the branding on the box.

Read 5 remaining paragraphs | Comments

Categories: News

The genetics of education: 1,271 genes account for 10% of the variation

Wed, 07/25/2018 - 17:43

Enlarge (credit: US Department of Education)

What's more important, genes or environment? It's an argument that goes back to well before the concept of genes was developed. The advent of genomics has given us a new perspective on the role of genetic variants in a lot of traits, but it hasn't necessarily stopped the arguing. The reasons are nicely highlighted by a new paper that describes a massive genetic screen for factors associated with educational success.

The study screened more than a million people for genetic variants associated with time spent in school. And while the study came up with a lot of genomic regions that were associated with schooling, the average difference made by each individual gene is only 1.7 weeks; collectively, the regions only account for a bit more than 10 percent of the differences in time spent studying. Critically, they may only be relevant to the European populations that were used to identify them.

Find the genes

Time spent in school is a rough measure of educational achievement. While there may be radical differences between two people who completed college, there's likely to be some consistent differences between people who quit after high school and those who pursued graduate study. And it seems to be a relevant measure in that it correlates with the improved economic and health outcomes that are typically associated with successful careers. And it's a less biased way of getting at educational achievement than things like standardized tests.

Read 10 remaining paragraphs | Comments

Categories: News

Possible lake spotted under a polar ice cap—on Mars

Wed, 07/25/2018 - 14:31

Enlarge / The highly reflective signals projected on top of a graphic showing Mars Express scanning the planet. (credit: ESA/Davide Coero Borga)

Today, a team of Italian scientists announced evidence that Mars has lakes of liquid water under its polar ice caps. While the evidence is a bit indirect and requires a number of assumptions, the alternatives that the researchers have considered fit the data worse. The announcement is likely to get scientists thinking about how to use existing instruments orbiting Mars to give this region a more careful examination.

Under the poles

Most parts of Mars spend much of the time at temperatures too low to support liquid water at the surface. Adding salt—and we've found lots of evidence of salt on Mars—can lower the freezing point of water by turning it into a brine. But that's not enough to overcome the extremely low pressures of the Martian atmosphere, which would cause any ice to sublimate off into vapor instead of melting.

So the only realistic hope for significant amounts of liquid water is under the surface, at sufficient depth to create enough pressure to allow salt to overcome the low temperatures. Calculations have suggested that these conditions may be met at the Martian poles, where large ice caps composed of both water and frozen carbon dioxide exist. There are obvious parallels to Antarctica, where lakes have been discovered beneath glaciers in several areas of the otherwise frozen continent.

Read 11 remaining paragraphs | Comments

Categories: News

Pages