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Game of Drones

Thu, 07/24/2014 - 16:02

Illustrations by Studio MUTI

Most pilots enjoy keeping their drones airborne. Marque Cornblatt, who studied digital art before turning to robotics, has different pleasure centers in his brain. “Crash your drone,” he says. “Get your hands dirty fixing that thing. Come up with solutions to keep it flying.”

This crash-and-rebuild philosophy came out of unmanned aerial vehicle (UAV) battles between Cornblatt and his friends. The duels were so much fun that they launched a group called Flight Club and the YouTube series Game of Drones. The show chronicles UAV dogfights, the building of unique battle drones—such as a paintball-shooting hexacopter—and abusive tests of a supersturdy airframe designed by Cornblatt and a buddy. (So far, it has survived flights through water, fire, and glass windows, drops from hundreds of feet, and even shotgun blasts.)

Cornblatt and his crew of daredevil drone pilots hope to grow their back-lot battles into a safe and watchable sport. To that end, they formed the Aerial Action Sports League, which borrows from the following Flight Club rules. Heed them if you dare.

The Rules

“If it flies, it fights.” Anyone who brings a UAV to Flight Club must enter it in combat. There are no rules for what a pilot can attach to it. 
“Knock the other guy to the ground.” After a crash, the grounded drone’s operator has some time—at least until the crowd gets antsy—to patch it up and get it working. 
“Two drones enter, one drone leaves.” The battle ends when one combatant has sustained too much damage to be revived. 

This article originally appeared in the August 2014 issue of Popular Science.








Happy Birthday, Chandra X-Ray Observatory

Thu, 07/24/2014 - 12:45

Supernova Remnant G292.0+1.8 One of four new images from Chandra. NASA/CXC/SAO

The Space Shuttle Columbia carried the Chandra X-ray Observatory into space on July 23, 1999. To commemorate the telescope's quinceañera, NASA has released four beautiful new images of supernova remnants, processed from Chandra's readings, that showcase the observatory's capabilities.

One of the agency's "Great Observatories" along with the Hubble and Spitzer space telescopes, Chandra does not take photographs, but rather makes detects X-ray emissions from "hot and energetic" areas of the universe, which can be rendered into images. The rig is named in honor of Nobel laureate astrophysicist Subrahmanyan "Chandra" Chandrasekhar (1910-1995). Since "chandra" also means both "moon" and "shining" in Sanskrit, the name seems especially appropriate.

NASA held an online hangout-birthday party on July 22 – which you can watch here – with Chandra scientists Steve O'Dell, Harvey Tananbaum, Julie Hlavacek-Larrondo and Scott Wolk. They chatted with the public about highlights of the mission and showed off amazing Chandra images.

View the gallery here.








Leishmania Parasite: Deadly For Humans, Good For Flies

Thu, 07/24/2014 - 11:22

This is a sand fly, an insect which spreads leishmaniasis. Rod Dillon

No human would be inclined to think favorably of leishmaniasis, caused by a parasite spread by sand flies, which infects about 12 million people worldwide and kills 20,000 to 30,000 per year

Leishmaniasis comes in two basic forms, cutaneous and visceral. The second is more serious, attacking the internal organs, and can lead to death if it's not treated. But cutaneous leishmaniasis is more visible, causing large (and egregious, unsightly) skin sores and lesion that can leave behind nasty scars. The cutaneous variety can also spread to the body's mucous membranes, creating sores in the sinuses and mouth--which can end up destroying them. Leishmaniasis is found in 90 countries, mostly in the tropics, from Latin America to Africa, the Middle East and South Asia. "Collectively the leishmaniases present a major global health problem, and are the second biggest parasitic killers worldwide after Malaria," Owens said. 

But it turns out that this "parasite" may actually be beneficial for the flies that carry it, by helping them to fight off infection from a different type of pathogen, new research shows.

It was previously known that various species of the Leishmania protozoa can shorten the lifespan of sand flies, especially if they are stressed (hey, flies get stressed too)--but according to the new study, published in the journal Parasites and Vectors, nobody had looked to see if the microbe might have beneficial effects for the insect. But that's just what a team of Brazilian and British researchers has done. When they exposed sand flies to a form of Leishmania protozoa found throughout Latin America, then exposed the insects to pathogenic bacteria, many more of the protozoa-carrying flies survived. In fact, at least five times more of the Leishmania-carrying flies lived after exposure to the bacterium (known as Serratia marcescens), compared to flies free of the protozoa.

The Leishmania parasite "works as a kind of probiotic and reduces the mortality of the fly," said study co-author Rod Dillon, a researcher at Lancaster University in the United Kingdom. 

"This is very interesting, as it is suggestive that similar mechanisms are operating here in the sandfly, as occurs in humans--i.e. that the ['good'] bacteria that inhabit your gut can protect you from pathogenic bacteria," said Ben Owens, an immunologist at the University of Oxford, who wasn't involved in the study. But in this case the Leishmania "is acting as a 'good' bug.'"

There are other instances of "parasites" having some beneficial effects for their hosts. For example, some helminths, or worms, can help regulate the immune system of animals that carry them, Owens told Popular Science. In fact, various helminths have potential to treat human autoimmune and gastrointestinal disorders like ulcerative colitis and Crohn's disease.

But not everybody is convinced. “I think it is really a stretch to say that the parasite has evolved to provide this protection,” George Dimopoulos, a professor of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health in Baltimore told The Scientist. “It’s more likely that Leishmania, as with all parasites that are transmitted by vectors, will turn on the sand fly’s immune system, which in turn is going to provide some level of protection against any other type of microorganism.” He added: “It’s not something that is necessarily specific to [Leishmania]."

The team had originally been looking to see whether they might be able to halt the spread of leishmaniasis by exposing sand flies to bacteria (to kill the flies, but perhaps also make the flies less likely to carry the protozoa). But exposing the flies to this bacterium, could ironically do quite the opposite. "Sand flies not carrying Leishmania may succumb more rapidly to the biological control agent and this would lead to the development of a wild sand fly population containing an increased proportion of the surviving flies carrying the human disease", the authors wrote. A scary thought.

There is no vaccine for leishmaniasis, and it can be difficult to treat--the standard therapy to date usually involves injecting patients with an antimony-containing compound that can have bad side effects. But for sand flies, Leishmania is not the horror it is for humans. 








An Animated Avatar Could Screen Humans For National Security

Thu, 07/24/2014 - 10:45

The Avatar Tested for National Security Interviews NCAA

When the paperwork at your doctor's office asks you how much alcohol you drink, do you write down the truth? Would you be more likely to tell the truth if an animated head interviewed you instead? One team of U.S. military psychologists is betting you would.

In a new study, researchers from the U.S. National Center for Credibility Assessment have determined folks are more likely to say more about their alcohol use and mental health history to an avatar on a computer screen than on a questionnaire, Vice's Motherboard reports. People's responses to questions about drug use and criminal history were about the same on questionnaires as to the avatar.

The NCCA software works with a decision tree that tells it what to say in response to people's answers, Motherboard explains. Its success with getting people to tell the truth has prompted the center to recommend avatars replace human interviewers during a preliminary step in earning national security clearance. The avatars would save the U.S. government time and money, the study authors write.

This isn't the first time scientists have thought of using computer-graphic heads to interview people, although it's the first I've heard of such interviews in connection with national security. Other researchers have focused on making software that screens people for depression. The software uses avatars to ask people questions and algorithms to analyze people's verbal and non-verbal cues while they're answering. From Motherboard's report, it's not clear to what extent the National Center for Credibility Assessment's software is able to analyze interviewees' non-verbal reactions… if it can't yet, that would surely be a powerful thing to add.

[Vice Motherboard]








Why DARPA Wants An Experimental Spaceplane

Thu, 07/24/2014 - 09:59

Artist's Concept for an Experimental Spaceplane DARPA

So DARPA wants a reusable spaceplane. I mean, who doesn't? For decades, space experts have tried to design quick-turnover, reusable launch systems. So far, however, no one has made one that works. "There really isn't any kind of vehicle today that does exactly what they're asking people to do," Micah Walter-Range, director of research and analysis at the Space Foundation, tells Popular Science. "You can certainly compare it to existing vehicles, but it seems to be a new class." 

Here's how the dream goes: Our fictional rocket would blast off at hypersonic speeds. Once it reached the right altitude, it would release any upper stages (and payload) it might have. Then it would turn back toward the Earth and land gently someplace where engineers would be able to fetch it, polish it up, and stick it back on the launch pad. Theoretically, reusable rockets should cut the costs of launches enough to open up space to more groups, such as students and startups, and ease NASA's financial burdens.

It'd be like having a jumbo jet for getting to space. Just load, unload, and repeat.

A few different groups have been working toward this goal recently. Last week, the U.S. Defense Advanced Research Projects Agency announced it awarded three teams contracts to make initial designs for just such a reusable small-satellite shuttle. One team is led by the Boeing Company, working with Blue Origin; Masten Space Systems, working with XCOR Aerospace, leads another; and Northrop Grumman Corporation, working with Virgin Galactic, make up the last. Meanwhile, SpaceX announced yesterday it completed a successful test on its way to making a reusable Falcon 9 rocket.

"There really isn't any kind of vehicle today that does exactly what they're asking people to do."

DARPA calls its version of this project Experimental Spaceplane 1, or XS-1. What the agency wants for XS-1 is unique. The craft should launch 3,000-pound to 5,000-pound unmanned payloads to low-Earth orbit for less than $5 million per flight. The whole launch process needs to be streamlined, too: DARPA wants to see 10 flights in 10 days.

For one thing, humans have never made launch vehicles with reusable rockets. Reusable passenger spaceships, like the vehicles Virgin Galactic is developing, are supposed to reach suborbital altitudes, not low-Earth orbit. NASA's Space Shuttles were reusable, but required days of refurbishing in between flights. Even among the one-time-use satellite launchers available today, none have quite the carrying capacity or price of Experimental Spaceplane 1. For example, Orbital Sciences' Pegasus XL carries just 1,000 pounds and costs an estimated $30 million to $40 million for a low-Earth-orbit flight. SpaceX's (current, non-reusable) Falcon 9 carries about 20,000 pounds, at a cost of $54 million per flight.

Cheaper launches would mean more people could send more stuff to space. DARPA hopes the XS-1, once launched, will serve the students and startups that build small, affordable cubesats, says Alan Wilhite, an aerospace engineering professor at Georgia Tech who previously worked on reusable shuttles at NASA.

"This is a DARPA-hard kind of problem."

In addition, a vehicle that could launch quickly could be helpful for military objectives. "Let's say you're planning a raid to find the next Osama bin Laden, something like that, and due to the timing of it, you don't have a satellite in the right place," Walter-Range says. "You have a small satellite on the ground and you just need to get it up tomorrow."

Right now, you would need to schedule a flight like that years in advance. With the XS-1's more frequent flying schedule, however, "you would just bump the next payload, put your satellite on there, and off you go," Wilhite says.

So why has nobody been able to make an XS-1 before? Different experts cited different reasons. Wilhite, who headed the Vehicle Analysis Branch at NASA Langley in the 1980s, points to technologies, such as hypersonic vehicles, that didn't previously exist. Getting an aircraft that's just rocketed up to the edge of space to come back down again—Gently! No crashes that would render the rocket unusable—is another tough problem.

Mitchell Walker, also an aerospace engineer at Georgia Tech, thinks XS-1's toughest hurdles would happen between its back-to-back flights. Once its reusable first stage reaches the ground, engineers would have make sure it's good to go again within 24 hours. "Anybody can get the engine back," Walker says. "The question is, can you convince yourself that it's okay to put your next multi-million-dollar asset on top of it?"

Extensive between-flights safety testing and refurbishing is why the Space Shuttle wouldn't fulfill DARPA's 10-flights-in-10-days requirement. Testing also added significantly to the Space Shuttle's costs.

Of course, the Space Shuttles carried astronauts, a load more precious than any multi-million-dollar NASA project. XS-1 would not only carry unmanned satellites, its 5,000-pound limit means those satellites would be small and likely not too expensive. No James Webb Space Telescopes here. So XS-1's customers might be satisfied with fewer, shorter safety checks, if that meant cheaper, more frequent flights.

Engineering-wise, there are a lot of variables to balance in the XS-1. "It's a really neat problem because it's got a lot of dynamics. Where are you hauling? What are you hauling?" Walker says. "This is a DARPA-hard kind of problem."








"Night's Slow Poison": An Excerpt From Our Sci-Fi Special Issue

Thu, 07/24/2014 - 08:00

"Night's Slow Poison" by Ann Leckie Illustration by Lisa Kay

This is an excerpt from Popular Science's special issue, Dispatches From The Future. Visit iTunes to download the edition onto your iPad, or return to our list of excerpts.

The Jewel of Athat was mainly a cargo ship, and most spaces were narrow and cramped. Like the Outer Station, where it was docked, it was austere, its decks and bulkheads scuffed and dingy with age. Inarakhat Kels, armed, and properly masked, had already turned away one passenger, and now he stood in the passageway that led from the station to the ship, awaiting the next.

The man approached, striding as though the confined space did not constrain him. He wore a kilt and embroidered blouse. His skin was light brown, his hair dark and straight, cut short. And his eyes . . . Inarakhat Kels felt abashed. He had thought that in his years of dealing with outsiders he had lost his squeamishness at looking strangers in the face.

The man glanced over his shoulder, and cocked an eyebrow. “She was angry.” The corners of his mouth twitched in a suppressed grin.

“One regrets.” Inarakhat Kels frowned behind his mask. “Who?”

“The woman in line before me. I take it you refused to let her board?”

“She carried undeclared communication implants.” Privately, Kels suspected her of being a spy for the Radchaai, but he did not say this. “One is, of course, most sorry for her inconvenience, but . . . ”

“I’m not,” the man interrupted. “She nearly ruined my supper last night insisting that I give up my seat, since she was certain she was of a higher caste than I.”

“Did you?”

“I did not,” said the man. “I am not from Xum, nor are we anywhere near it, so why should I bow to their customs? And then this morning she shoved herself in front of me as we waited outside.” He grinned fully. “I confess myself relieved at not having to spend six months with her as a fellow passenger.”

“Ah,” Kels said, his voice noncommittal. The grin, the angle of the man’s jaw—now he understood why the eyes had affected him. But he had no time for old memories. He consulted his list. “You are Awt Emnys, from the Gerentate.” The man acknowledged this. “Your reason for visiting Ghaon?”

“My grandmother was Ghaonish,” Awt Emnys said, eyes sober that had previously been amused. “I never knew her, and no one can tell me much about her. I hope to learn more in Athat.”

Whoever she was, she had been from the Ghem agnate, Kels was certain. His eyes, his mouth, the line of his chin . . . With just a little more information, Kels could tell Awt which house his grandmother had been born in. “One wishes you good fortune in your search, Honored Awt,” he said, with a small bow he could not suppress.

Awt Emnys smiled in return, and bowed respectfully. “I thank you, Honored,” he said. “I understand I must disable any communications implants.”

“If they are re-activated during the voyage, we will take any steps necessary to preserve the safety of the ship.”

Awt’s glanced at the gun at Kels’ waist. “Of course. But is it really so dangerous?”

“About three months in,” said Kels, in his blandest voice, “we will pass the last ship that attempted to traverse the Crawl with live communications. It will be visible from the passengers’ lounge.”

Awt grinned. “I have an abiding wish to die old, in my bed. Preferably after a long and boring life tracking warehouse inventories.”

Kels allowed himself a small smile. “One wishes you success,” he said, and stepped aside, pressing against the wall so that Awt could pass him. “Your belongings will be delivered to your cabin.”

“I thank you, Honored.” Awt brushed Kels as he passed, awakening some unfamiliar emotion in him.

“Good voyage,” Kels murmured to the other man’s back, but there was no sign Awt had heard.

#

Ghaon is a moonless blue and white jewel orbiting a yellow sun. Its three continents provide every sort of terrain, from the great deserts of southern Lysire, and the rivers and gentle farmlands of the north and west of that same continent, to the mountains of Aneng, still fitfully smoking. Arim, the third continent, is arctic and uninhabited. Aside from the sorts of industry and agriculture that support the population of any world, Ghaon produces pearls and ingeniously carved corals, which, when they find their way outside the Crawl, are highly valued. Flutes carved from the wood of Aneng’s western forests are prized by Gerentate musicians.

According to legend, the first inhabitants of Ghaon came from a world called Walkaway, the location of which is unknown. There were thirteen original settlers, three agnates of four people each plus one eunuch priest of Iraon. The three agnates parceled out the world among themselves: Lysire, Aneng, and the surface of the sea. The priest blessed the division, and each agnate prospered and filled the world.

The legend is only that, of course. It is impossible that thirteen people would possess the genetic diversity required to populate a planet, and in any case studies show that the first human inhabitants of Ghaon, whose descendants now populate Lysire and Aneng, derived largely from the same populations that eventually made up much of the Gerentate. The ancestors of the sea-going agnates arrived several thousand years later, and their origins are obscure.

In any case, the first colonists must have either known about the Crawl before they arrived, or constructed it themselves. The latter seems staggeringly unlikely.

Gerentate explorers found Ghaon some years after that entity’s expansionist phase had run itself out, and so the only threat they presented was a trickle of ill-bred, bare-faced tourists.

But the Radch was another matter. Every soul on Ghaon, from the smallest infant at the breast to the most ancient Lysire matriarch in her tent on the edge of the drylands, believed that the nefarious Anaander Mianaai, overlord of the Radch, had cast a covetous eye on Ghaon and contemplated how he might make it his own.

To keep reading, visit iTunes and download our Dispatches From The Future special issue onto your iPad.








Introducing Our First Sci-Fi Special Issue For The iPad

Wed, 07/23/2014 - 12:30

Dispatches from the Future Download a copy from iTunes. Popular Science

We love science fiction here at Popular Science. Many of the real-life innovations and advances that fill our pages every month, in fact, started as pie-in-the-sky ideas born by people thinking creatively about a better future. These visions only get more vivid, the stories more stimulating and innovative, as we craft each new issue.

So today we present something extra-special, called Dispatches From The Future: an entire digital issue packed with more than 100 pages of awesome science fiction and designed for the iPad. You can download a copy from iTunes here.

Our crown jewel in this edition is the first-ever graphic novel adaptation of the Isaac Asimov classic Nightfall, complete with animations. Also included are amazing short stories by award-winning sci-fi authors Will McIntosh, Ann Leckie, and Seanan McGuire. Finally, we've folded in collections of original science fiction we produced in 2013 and 2014, which feature some of the brightest minds in the field musing how we will live—on Earth and beyond—in the decades and centuries to come.

We're publishing excerpts of Dispatches From The Future here, one per day, to give you a taste of the issue. (Each cover image will stay grayed-out until that excerpt is posted.) So keep checking back throughout the week—if you can wait that long!

"The Defenders" by Will McIntosh

"The Defenders" by Will McIntosh Illustration by Lisa Kay

Twenty-eight years ago, humanity was almost wiped out by invaders called Luyten. But human-created artificial intelligence saved humans in the nick of time. Now, after decades of self-imposed exile in Australia, the A.I. defenders are allowing a few humans to visit. The human ambassadors have no idea what is in store. [Click to read an excerpt]

"Night's Slow Poison" by Ann Leckie

"Night's Slow Poison" by Ann Leckie Illustration by Lisa Kay

Many worlds away, Inarakhat Kels paces the halls and corridors aboard an interstellar cargo ship on a six-month journey between planets. He and the other members of his security watch keep on the lookout for treacherous spies, harmful technology, and anything else that might put the ship and its inhabitants at risk of destruction. On this particular trip, a meeting with a peculiar traveller forces him to confront the memories of the home-planet he abandoned long ago, and of a lost-love he was forced to leave behind. [Click to read an excerpt]

"The Tolling of Pavlov's Bells" by Seanan McGuire

"The Tolling of Pavlov's Bells" by Seanan McGuire Illustration by Lisa Kay

Dr. Diana Weston is a virologist and a bestselling author, with a penchant for writing medical thrillers about catastrophic disease outbreaks. But underneath her attractive smile and sharp wit lies a troubled psyche. When the fictional plots she pens start showing up in the real world, the dark side to her life begins to come out of the shadows. [Excerpt coming soon]

"Nightfall" by Isaac Asimov

"Nightfall" by Isaac Asimov Illustration by Ryan Inzana

The scientists of Saro University have predicted civilization's impending doom, caused by the extinguishing of the planet's last light-giving star in just four hours. But some are skeptical that the Darkness will have the effect that the scientists anticipate, so a young journalist has come to seek the truth. His shocking discovery is a story for the ages. [Excerpt coming soon]

Download our entire Dispatches From The Future special issue for the iPad from iTunes.








Could This Old Warplane Really Shoot Down MH17?

Wed, 07/23/2014 - 11:44

An Su-25 In Flight Wikimedia Commons

Following the downing of Malaysian Airlines flight MH17 over separatist-held eastern Ukraine, Russian state-owned media started focusing a lot on a strange little plane. The Sukhoi Su-25 "Frogfoot" is a jet fighter from the late Cold War, designed to support ground troops from closer overhead, and in the MH17 tragedy, what the Su-25 can and can't do is a centerpiece of Russian denials.

According to some theories, a Ukrainian Air Force Su-25 jet fighter fighter was armed with anti-air missiles and flew to an altitude of 33,000 feet, within 3 miles of MH17–implying that the warplane shot down MH17. Primarily Russian media (including Russia's state-owned English language television network RT, Russian state-owned media news agency RIA Novosti, and Pravda.ru) are reporting this version of events. Russia is hardly an unbiased party in this conflict. But if there was going to be a rumor about the Ukrainian government shooting the airliner, it couldn't have fixated on a less ideal jet.

The Sukhoi Su-25 "Frogfoot" is not designed to destroy airplanes. Instead, it's a close air support or ground attack aircraft. First flown in 1979, it serves in the air forces of many post-Soviet states, including Ukraine. It's primarily used for destroying tanks, armored vehicles, trucks, and bunkers, where the Frogfoot's armor and 9,000 lbs of armaments make it a deadly force. Among those armaments can be AA-8 Aphid anti-air missiles, which are usually limited in range to under two miles. But there's an upper limit to the plane's performance: it can only fly up to 23,000 feet, well below MH17's reported 33,000 cruising distance. For an anti-tank plane, that's not a problem, but it poses a challenge to theories that Ukraine used one to down an airliner.

On Monday morning, someone from an IP address in Moscow edited the Su-25's Russian Wikipedia page to increase the maximum height the plane can reach by about 10,000 feet. 

On the website of the Su-25's manufacturer, the maximum service ceiling reflects the first version, and also the actual capabilities of the plane. It's not just absurd that a Ukrainian Su-25 shot down the airliner, it's almost technically impossible.

Instead, it looks like the Su-25 has a more somber connection to MH17. Earlier today, two Ukrainian Air Force Frogfeet were shot down in the same region of separatist-held eastern Ukraine where MH17 met its grim fate.

Su-25 At Kubinka Air Base Dmitry A. Mottl, via Wikimedia Commons

 








101-Year-Old Citizen Scientist Has Called In Weather Observations Every Day For 84 Years

Wed, 07/23/2014 - 10:28

Richard Hendrickson Takes a Weather Measurement, 2008 NOAA

Generations before anyone came up with the idea of "citizen science," an 18-year-old Richard Hendrickson called in his first weather report to what was then the U.S. Weather Bureau. That was in 1929. Hendrickson is now 101 years old and has provided the National Weather Service with twice-daily observations from his Long Island farm for 84 years.

Hendrickson is a part of the Cooperative Observer Program, a network of more than 8,700 volunteers who set up stations around their homes and send in reports about the temperatures, snowfall and rainfall they measure. Formally established in 1890, the network helps the National Oceanographic and Atmospheric Administration track global warming over time. It also helps NOAA send out real-time flood warnings. Hendrickson provided measurements during that hurricane that damaged so many houses on Long Island—you know, the one in 1938?

Then and Now On the left, Richard Hendrickson looks at the Atlantic Ocean during a storm in the 1930s. On the right, he takes weather measurements sometime in 2014. Left photo by D. L. Hendrickson; right photo by Sara Hendrickson

NOAA has never had a volunteer serve for more than eight decades, the agency says. So, this month, it's created a Richard G. Hendrickson Award, for volunteers who serve for 80 years. Other prestigious Cooperative Observer Program awards are named after Thomas Jefferson, who recorded weather observations for 40 years, and John Campanius Holm, who made the first recorded observations in the U.S., between 1644 and 1645.

Hendrickson goes out to make his observations no matter the weather. In fact, he told NOAA, he prefers it if things are a little exciting: "Taking the weather every day, on nice days, it's monotonous, but then you get the thunder and lightning—bam!" See him talk about the weather, and work at his weather stations, below. Congratulations, Mr. Hendrickson!








World's Largest Aquatic Insect Reportedly Found In China

Wed, 07/23/2014 - 08:45

Sweet dreams This is reportedly a giant Dobsonfly, the world's largest, with a wingspan of 21 centimeters (8.3 inches), large enough to cover your face. China News Service/ Zhong Xin

Gadzooks! The world's largest aquatic insect has reportedly been found in China. This cute/terrifying little creature, which is definitely worth writing home about, was found in the the mountains of Chengdu in Sichuan province, Scientific American reports. It boasts a wingspan of 8.3 inches. That breaks the previous record held by a species of South American helicopter damselfly, with a wingspan of 7.5 inches. (Helicopter damselflies, by the by, feed on spiders, one species of which makes fake spiders in its web, likely to scare the predators away.) 

There seems to be some confusion about exactly what this new insect is. Scientific American reports that they have only been identified as being the order Megaloptera, which includes alderflies and Dobsonflies, while CNN quotes a local museum as saying they are giant Dobsonflies (note: these are not mutually exclusive).

The adult insects lay their eggs in water, and larvae grow up in and around sediment at the bottom, and then as adults emerge from the depths to become, basically, flying jaws. 

They are the largest aquatic insect, but what about the largest insect overall? It depends whether you're after weight or length but here are the contenders, as SciAm noted: 

On the hefty side, we’ve got the Little Barrier Island giant weta (Deinacrida heteracantha) – one very famous specimen of which weighed 71 grams [0.2 lb]... Found in a remote region of New Zealand by biologist Mark Moffett, the weta was given a carrot to munch on while her photo was taken... 

On the more lanky side is the aptly named megastick – Chan’s megastick (Phobaeticus chani). The body of a female Chan’s megastick measures 35.7 cm (14 inches), which is a world record for insect body length. Oh and its legs? They’re 56.7 cm (22 inches) long.

A close-up of the insect's mandibles. China News Service/ Zhong Xin

[Scientific American / China News Service]








Here's Our Original Coverage of Apollo 11

Wed, 07/23/2014 - 08:00

Forty-five years ago, on July 20, 1969, Neil Armstrong and Buzz Aldrin made the first footprints on the Moon, and it was epic. Popular Science covered this enormous achievement with an article by Wernher von Braun– a German-born engineer, now known as "The Father of Rocket Science,"  who built the Saturn V launch vehicle that brought Apollo to the Moon. In our July 1969 issue, he described the plans for Armstrong and Aldrin's two-hour rendevous with the Moon. (You can read the story in its original format here, although for mysterious reasons, two pages are missing.) 

From The Archives. Popular Science's original coverage of the Apollo 11 moon landings, July 1969.

First Men On The Moon

By Dr. Wernher von Braun

In the two-man cabin of the Apollo 11 Lunar Module, slowly riding down its vertical rocket jet, blue signal lights flash on. Probes dangling 60 inches below the disk-shaped footpads have touched the moon. The pilot cuts the engine. A moment later, a mild jar tells the crew they have landed on the moon's surface.

That is to happen early in the afternoon of Sunday, July 20, 1969, in the western part of the moon's Sea of Tranquility, according to NASA's plans at this writing. Chosen to attempt the first manned lunar touchdown are Apollo 11 Commander Neil Armstrong and Lunar Module Pilot Edwin ("Buzz") Aldrin. Circling above the landing site in their moon-orbiting mother spaceship, in the Command and Service Module, will be Command Module Pilot Michael Collins.

Success in Apollo 11's great adventure would realize our aim of putting men on the moon within this decade. Millions of Americans will share the suspense and thrills of the fantastic mission as they watch it unfold on their TV screens. Here is an advance look at what the Apollo 11 astronauts mean to do, and a guide to key events on which success will hang:

Original Caption From 1969: Moon-landing flight plan of Apollo 11 is shown by diagram. What's never been done before begins with braking maneuver labeled Powered Descent Initiation, and ends with touchdown.

The dash to the summit.

Man's first touchdown on the moon can be compared to the final spurt to a lofty mountain's summit by a few select climbers, starting from the highest of a string of base camps set up by others of their expedition. 

Apollo 7 proved out the Comand and Service Module (CSM). Apollo 8's moon voyage took men in and out of lunar orbit. Separating and docking the Lunar Module (LM) was rehearsed in earth orbit by Apollo9, and over the moon by Apollo 10. Now all is ready for the assault on the summit–the moon landing itself.

Apollo 11, up to a point, will retrace the moon-voyaging route of Apollo 8 and 10: the Saturn V launch into earth orbit, scheduled for July 16; re-ignition of the Saturn V's top stage, to propel the craft into a coast to the moon; and rocket braking to put Apollo 11 in a lunar orbit, 70 statute miles above the surface. (The "go" for each major maneuver will mean that crew and spacecraft are in perfect shape so far; should trouble strike, anywhere along 'the way, the mission would be aborted and the crew brought back.

Then the Lunar Module with its crew of two is to separate and make a rocket braking burn that, in an hour, brings it down to 50,000 feet above the moon. This maneuver has been performed before only by the Apollo 10 astronauts.

From here on, Apollo 11's Lunar Module will blaze a new trail.

Coming in to Iand.

The all-clear for what has never been done before will be the radioed word from Mission Control at Houston: "You are go for PDI." That stands for Powered Descent Initiation, the start of rocket braking so forceful that it commits the Lunar Module to a lunar landing attempt within minutes.

Feet first, the Lunar Module is skimming the moon at about 4,500 m.p.h., when its crew fires its descent engine straight forward. The retro-burn lasts six minutes at full 10,000-pound thrust–and two minutes more, with the LM now lightened by propellant consumption, at 6,000-pound thrust. That "braking phase" kills almost all forward velocity. It leaves the Lunar Module nearing the landing site at airplane-like speed of only a few hundred miles an hour. 

As the craft turns upright, the moon's surface, out of sight of the crew before, creeps into view from the bottom of their windows.

A landing radar has begun reporting altitude and velocity-data so vital that the landing attempt would have to be abandoned if the radar beams failed to "lock on" to the moon's surface. At a point called the High Gate, less than five miles from touchdown, the falling craft is down to 7,000-foot altitude–and enters the Final Approach Phase. It begins tilting toward vertical and using its descent engine to check its fall.

As it turns upright, the moon's surface, out of sight of the crew before, creeps into view from the bottoms of their windows. What they see is a flat and comparatively crater-free lunar plain–almost on the moon's equator, at 23 degrees east, lunar longitude.

Look at the moon from earth and this landing site will be a little short of midway from the moon's center to its righthand edge. At the time of the landing, when the moon will be nearing "first quarter," it is barely within the sunlit zone. Purposely the touchdown is timed for early in the lunar morning, so that long shadows will vividly show up the relief of the terrain.

Selecting a landing spot free of obstacles, the crew tilts the whole craft until this target is at the zero point of a windowpane scale, whose fluorescent markings glow green and orange in the dark. Then they trigger a "mark" button to pin it down. This sets their inertial-guidance system to lead their descent path to it automatically.

At a point less than 1,000 feet up, called the Low Gate, the Final Approach Phase ends and the Landing Phase begins. The crew can choose an "auto" mode that does it all automatically; a semiautomatic mode, in which the LM Pilot controls the rate of descent; or a completely manual mode for a helicopter-style landing by eye. A likely choice is the semiautomatic mode.

The hovering Lunar Module descends toward a touchdown at three feet a second. Any remaining horizontal velocity will be even less. Keeping it to a minimum, and avoiding sloping ground and obstacles, are important to avert a disastrous tip-over. The LM is pretty forgiving about a less-than-perfect landing–but, even so, it will be a tense moment when the spidery legs' footpads settle into lunar soil.

After the dramatic news that the crew are safely down on the moon, a little time elapses before further events, for the astronauts do not emerge at once. It takes them awhile to check their craft, and then struggle into "moon suits" with life-support backpacks, even if they should forego a rest period before their strenuous activities outside.

Moon men rehearse lunar-surface tasks at Houston. Antenna snaps into shape of upside-down umbrella as Apollo 11 Commander Armstrong triggers spring. LM Pilot Aldrin (background) unstows a rock scoop.

Footsteps on the moon!

Finally comes the high spot of the mission–an action-packed program of two hours and 40 minutes of "moonwalking." Descending a ladder from the forward hatch, Commander Armstrong is to be first to set foot on the moon. Almost his first act is to scoop up a bagful of loose lunar soil, and hand it up to Aldrin to stow away. That "grabbag" sample guards against returning empty-handed, if anything should compel a premature takeoff. (You may be sure planners are thinking of nothing so fanciful as a hostile reception by little green men–but of such imaginable contingencies as a leak in the ascent propulsion system, or trouble with life-support equipment.) Then, after Armstrong has tested walking on the moon, and inspected the craft's exterior to make sure it has suffered no damage in landing, Aldrin joins him outside.

Earth viewers will share by TV the eerie lunar scene confronting them–a stark gray desert, airless and lifeless, unrelieved by colors, harshly painted by the sun with glaring highlights and inky shadows. High in the black sky hangs the remote earth. The only nearer human being is Collins in the CSM, which they see sail overhead every two hours. Their mothership looks to them like a star, except that it is moving rapidly across the heavens, as it orbits the moon. 

Dark gold-coated visors of the moon-explorers' red helmets shield their eyes from the sun's glare. They wear heavily insulated "lunar overshoes"; underfoot, the moon's soil is still frigid after the extreme cold of the 14-day-long lunar night, although it will become hotter than boiling water during the equally long lunar day.

Their TV views and their voices, via their walkie-talkies, are beamed to earth by a radio antenna shaped like an upside-down umbrella, which they have erected on the lunar soil. Eager shutterbugs, they snap away with film cameras, too.

Using long-handled scoops, tongs, and shovels for rock collecting, since they cannot bend over in their suits, they finish filling two "rock boxes" with carefully selected lunar specimens, individually sealed in plastic bags.

Astronauts, who cannot bend over in backpack-laden garb, pick up moon rocks with long-handled scoops as in NASA trial pictured above.

Science package for the moon.

Setting up three scientific experiments, of which two are left on the moon, completes the lunar explorers' busy program. 

A "moonquake detector," powered by solar panels, is expected to report any seismic activity to the earth by radio for a year. It is so sensitive that it may transmit the sound of the astronauts' footsteps as they walk away. 

An array of 100 disk-shaped quartz reflectors, inclined to face the earth, will bounce back laser beams shot at it from earth stations. Through its use, scientists hope to measure earth-moon distance with unprecedented accuracy–and also to gauge the precise distance between laser stations on earth, for such purposes as testing theories of continental drift.

A sheet of plain aluminum foil, which the LM crewmen spread on the ground when they leave the craft and pick up again when they return, is a take-home experiment. Later it will reveal the composition of "solar wind" when it is tested for entrapped helium, neon, and other rare gases.

Together the three experiments–called EASEP, for Early Apollo Scientific Experiments Payload–weigh 171 earth pounds, or less than 30 pounds on the moon. Deploying them should take as little as 10 minutes. To avoid overtaxing the first moon men, NASA decided that bringing a more elaborate science outfit (called ALSEP, for Apollo Lunar Surface Experiments Package) would await subsequent moon-landing expeditions.

In the limited time of their sortie on the lunar surface, the explorers range no farther than 50 to 100 feet from their spacecraft. Returning to it, they spend the remainder of their 22 hours on the moon in resting from their demanding tasks, and in an elaborate prelaunch checkout of the equipment to be used in rejoining the orbiting CSM. 

Earth viewers will share by TV the eerie lunar scene confronting them–a stark gray desert, airless and lifeless, unrelieved by colors, harshly painted by the sun with glaring highlights and inky shadows. High in the black sky hangs the remote earth.

"Fire in the hole."

The first manned takeoff from the moon will be due about noon on Monday, July 21. Safety of the astronauts and their precious specimens will depend oh the success of the "FITH" launch of their spacecraft's ascent stage. FITH stands for Fire in the Hole, and means that there is no separation of the stage prior to ignition of its ascent engine, nor is there a jet deflector of any sort. Having served its purpose, the now-expendable descent stage serves as a launch platform for the ascent stage, and damage to it from the ascent engine's fiery jet will not matter. 

For the first eight seconds the ascent stage climbs vertically, under its engine's 3,500-pound thrust. Then it rather abruptly pitches downward about 50 degrees. Safely above lunar mountains and with no atmosphere to limit speed, it builds up horizontal velocity as fast as possible.

Seven minutes and 16 seconds after takeoff, the Lunar Module is speeding nearly horizontally at almost 3,400 m.p.h., 60,000 feet above the lunar surface. It is safely inserted in an elliptical orbit with a high point of 52 statute miles. If anything should go wrong with it now, the Command and Service Module can come to the LM crew's rescue.

An hour later, the LM ascent stage circularizes its orbit at the high point, by adding a little speed with its small reaction control thrusters. Then a smaller nudge with them adjusts the altitude to put the craft just 17 and 1/4 miles below the CSM, and corrects any minor difference in their orbital planes. Now, from behind and below, the ascent stage makes its rendezvous-and-docking with the CSM.

The rest–the start for earth, the long coast through space, the high-speed re-entry and splashdown in the Pacific–will be a repeat of Apollo 8 and 10, up to the recovery of the astronauts and the Command Module.

Into quarantine.

Then comes the mission's strange conclusion–quarantining the moon heroes and their lunar samples for at least three weeks, in the Lunar Receiving Laboratory at Houston [PS, Oct. '68]. It is a precaution against the chance they might have brought back living organisms–probably unknown on earth and possibly harmful to humans, animals, or plant crops here–although scientists consider it far more likely that the moon lacks any life whatever. Within on ly a few weeks we may have the first hard evidence, pro or con.

Apollo 11's flight is only a beginning, a scouting expedition. Nine more Apollo landings at different sites on the moon are planned by NASA; the next one, Apollo 12, is scheduled for this November. But the first manned landing on the moon will be an epic achievement–the conquest of the greatest engineering challenge we have ever faced.

This article originally appeared in the July 1969 issue of Popular Science.








Uncontacted Amazonian Tribe Voluntarily Contacts Scientists, Catches Flu

Tue, 07/22/2014 - 17:02

Amazon Rainforest This photo was taken near the city of Manaus, Brazil, which is northeast of the Acre region discussed below. Phil P. Harris on Wikimedia Commons, CC BY-SA 2.5

Late last month, something extraordinary happened at the edge of the rainforest in Acre, Brazil. Members of an uncontacted Amazonian tribe voluntarily approached scientists from the Brazilian government, Science magazine reports. This is the first time in decades that an uncontacted community chose to meet with outsiders.

Unfortunately, although peaceful, the encounter wasn't without its problems. FUNAI, Brazil's Indian protection agency, recently announced that some of the tribespeople caught a flu. For people who have never encountered flu viruses, such infections can be deadly. It's not clear whether the tribespeople got sick before or after meeting scientists, but FUNAI said once the agency realized what had happened, a medical team treated the sick tribal members and gave them flu shots. Then the members decided to return to the forest. Outside researchers are now worried the sick tribesmembers weren't treated in time to prevent them from infecting others in their village, Science reports.

Officials think tribe members made contact because they have been violently harassed by drug traffickers and/or illegal loggers. They were also raiding mainstream indigenous villages in the area for food and tools. The flu could have come from the traffickers, the villagers, or the scientists tribal members ultimately met with.

Just a note: As you might expect, many "uncontacted" tribes actually have had some interactions with outsiders... just not good ones. Instead, they've chosen to avoid mainstream people after rubber tappers in the 19th and 20th centuries killed 90 percent of their populations through fighting, enslavement and disease. At the same time, it's important not to underestimate the number of uncontacted people, nor the extent of the isolation they've been able to secure for themselves. In the past, government officials have claimed environmentalists made up uncontacted tribes to prevent companies from developing regions of the rainforest. Isolated tribes do exist, and have a legal right to be left alone on their land. The official policy of FUNAI is not to interact with Acre tribes unless the agency thinks tribal members are in danger.

[Science]








How Climate Science Gets Done In The Icy Fjords of Greenland

Tue, 07/22/2014 - 15:47

View from an Iceberg Magnus Petersen and Dave Porter prepare to lower a temperature-depth-salinity sensor into a fjord near the village of Kullorsuaq, as part of a study into changing conditions where Greenland's melting glaciers meet the ocean. Margie Turrin/LDEO

Do you wonder what doing climate science in remote locations might be like? Read the Greenland Thaw blog, which is being updated regularly from the fjords of northwest Greenland, where the giant island's glaciers meet the ocean. With Greenland's ice sheets melting faster than ever, the study's scientists want to document and understand why the Alison Glacier, on Greenland’s northwestern coast, is flowing to the sea faster than other glaciers in the area.

This is not a Jacques-Cousteau-waxing-poetic-aboard-the-Calypso type of expedition. Rather, it involves working out of a small, open, benzene-fueled boat owned and operated by a local fisherman. But hopefully the spectacularly beautiful scenery makes up for the raw working conditions.

Yesterday blogger Margie Turrin, an education coordinator with Columbia University's Lamont-Doherty Earth Observatory, described collecting samples along the water column: “The science goal for today is to complete 8 CTD casts,” Turrin writes. (CTD stands for conductivity - a measure of salinity – temperature and depth).

We load into our vessel, a Poca 500GR. We have discussed a 6 to 8 hour window of boat time with Gabriel the captain and Magnus our navigator and stocked up on 40 liters of benzene. The benzene sits in a clear jug by my side, from there funneled into the motor...

The winch set-up is one that is comfortable to the Greenlandic as they use it to lower line 1000 meters down for fishing.  Several times during such a trip they will load hooks for 200 or more fish onto the line, lowering and hauling it back up by hand crank.

After the first cast we are faced with iced in conditions.  Gabriel maneuvers the boat as best he can but we will not be able to get to the point we had hoped to collect next.  Everywhere we look we are surrounded by ice, bits of mélange (ice rubble) cover the ice surface interspersed with larger icebergs.  We attempt to make our way down different channels to see if there is a pathway around some of the ice but it appears we will need to make adjustments to the cast points.

As well as taking ocean samples themselves, the scientists say they will work with villagers of tiny nearby Kullorsuaq to continue collecting data after the researchers have left.








MERS Virus May Be Able To Spread Through The Air

Tue, 07/22/2014 - 13:57

Dromedary camels, which can carry MERS. Wilson44691 via Wikimedia Commons

Research strongly suggests that camels carry Middle East Respiratory Syndrome (MERS), a viral illness that has sickened nearly 700 and killed at least 209 people as of early June, according to the latest update from the World Health Organization. For this reason, the government of Saudi Arabia recently warned people to stay away from close contact with camels, at least those that appear to be sick, which prompted some to defiantly post photos of themselves kissing camels on various social media sites.

Until now it was thought that MERS could only be spread via close contact, but a new finding may challenge that assessment: A study published in the journal mBio found the virus in an air sample taken from a camel barn near Jeddah, Saudi Arabia. The genetic signature of the virus was identical to that found in the sick camels, and the owner, who came down with MERS a week after administering a topical medicine to his camels' runny noses. The owner later died from MERS.

"The clear message here is that detection of airborne [MERS] molecules, which were 100 percent identical with the viral genomic sequence detected from a camel actively shedding the virus in the same barn on the same day, warrants further investigations and measures to prevent possible airborne transmission of this deadly virus," said study lead author Esam Azhar, a virologist at King Abdulaziz University in Jeddah. The finding implies that virus could possibly be spread in enclosed spaces such as hospitals and therefore "further studies are urgently needed," the scientists wrote.

The scientists took air samples and looked for the DNA found in MERS viruses on three consecutive days. They only found the virus one of the days, the same day that one of the camels tested positive for MERS. This suggests that MERS may not last long in the air, which would be welcome news. 

In May, the CDC reported the first case of a man getting the MERS virus in the United States without traveling to the Middle East--though luckily the man didn't appear to have symptoms and wasn't considered contagious. 








How To Watch An Animal Develop Cell By Cell

Tue, 07/22/2014 - 12:15

2,458 Cells Fernando Amat et al., "Fast, accurate reconstruction of cell lineages from large-scale fluorescence microscopy data," Nature Methods, 2014

What is this fuzzy creature? Sadly, it's not pettable. This is a microscope image of a fruit fly embryo, showing the individual cells within it. That's 2,458 cells, to be exact. The bottom image shows each cell in a different color, with lines to show how those cells moved around.

The image comes from a new technique scientists developed to watch every single cell in an early embryo and record what it does. Where does each cell go? When does it divide into two cells, and where do each of those two cells go? How do genes control what cells do? These are some of the most basic questions in biology.

Of course, previous generations of scientists have developed their own cool methods for answering these questions. But none of the methods is perfect. A human couldn't do such tracking without computer help, but even for a computer, it's difficult to keep tabs on thousands of moving, duplicating cells at once. In this latest work, a team of biologists from the Howard Hughes Medical Institute is releasing, for free, its method for recording embryotic development automatically. The technique is able to track up to 20,000 cells at once and is 97 percent accurate. The team has used it to watch the development of fruit fly, zebrafish and mouse embryos—basically, how these animals are built from the ground up. The idea is that animal species are similar enough that scientists are able to learn some basic principles about how humans develop by watching lab animals, using techniques it would be unethical to apply to a human embryo.

The Howard Hughes scientists used several clever solutions to deal with the terabytes of data embryo-tracking creates. They packaged individual pixels up into "superpixels," here called "supervoxels" because they're 3-D. The biologists' computer program also automatically recognizes and fixes parts of its dataset where it might have made mistakes in tracking. (Like human eyes, computer vision can have trouble distinguishing cells if they're too close together, which often happens in embryos.) The result is a program that's more accurate and more than 10 times faster than previous programs, according to a paper the team published this week in the journal Nature Methods.








Could Lasers Be The Future Of Anti-Missile Weapons?

Tue, 07/22/2014 - 11:31

American Concept Art Of Soviet Laser. From 1986. Edward L. Cooper, via Wikimedia Commons

On Thursday, July 18th, Malaysian Airlines flight MH-17 was struck by a missile. The United States believes the missile was a Soviet-designed Buk, and American infrared satellites pinpoint the location of that missile's launch to territory in Eastern Ukraine held by Russian-backed separatists. Is it possible that, while Cold War technology launched the missile, and modern technology identified where it was launched, future laser technology could shoot missiles out of the sky?

The answer is a strong and definitive maybeOutfitting modern commercial airliners with anti-missile lasers is a much more expensive and complicated process than simply not flying over war zones, and even if current lasers work against small missiles, they can't yet stop larger anti-air weapons. A recent op-ed in the Wall Street Journal argues that anti-projectile lasers, for weapons smaller than missiles, are feasible now. The National Defense Magazine sees a more gradual development of anti-missile lasers. Though the technology is still in labs and proving grounds, the growing field of energy weapons suggests that a future filled with protective lasers is possible. 

The Current State Of Anti-Projectile Weapons

Hitting objects in mid-air is hard, and it's expensive. American efforts in ballistic missile defense, a long-promised countermeasure to nuclear attack, are often so unsuccessful that Congress recently specified that new tests must be realistic when it authorizes funding. Even when not stopping nuclear armed intercontinental ballistic missiles, hitting a rocket with a rocket is tricky. Israel's Iron Dome rocket defense system costs $45 million for a group of launchers and $40,000 for each counter-rocket fired. The rockets it's designed to stop cost around $750 apiece to make. That's $40,000 for each attempt to stop a $750 rocket, which means the system can be quite costly monetarily and in human lives if Iron Dome's accuracy is less than explicitly promised

Lasers could change that equation. Laser systems are expensive to develop; the U.S. Navy has already spent $40 million and counting to build a laser that would shoot down drones, and improving the laser will undoubtedly cost more. Once developed and put into use, though, lasers get very, very cheap. As designed, the Navy laser system costs about $1 a shot, making it cheaper than bullets used for the same purpose.

Because lasers are beams of light, they travel faster than any other projectile weapon. Lasers are thus ideal for stopping other projectiles. In the words of Lockheed CTO Ray Johnson, "It’s game changing. Should you develop an operational weapon that operates at Mach a million, that’s game changing." To get to that gamechanging point, lasers will need to be a lot more powerful than they currently are. 

Laser Weapons Today

Johnson estimates that 100 kilowatt lasers will debut over the next few years, and he thinks 300kW lasers will be feasible eventually. Even at 10kW, today's lasers show promise. Last winter, the U.S. Army's "High Energy Laser Mobile Demonstrator" (HEL MD) used a 10kW beam to "engage" mortar rounds in midair. "Engage" is a bit of a dodgy word here that means "aimed at and hit" while not specifying "until successfully destroyed." The Army plans to keep developing the HEL MD at 50kW and 100kW levels, with the goal of creating a laser so powerful it can damage mortar rounds, steer them of course, and maybe even blow them up. Israeli defense company Rafael is also developing a laser weapon system, and the Office of Naval Research is looking into a truck-borne version for U.S. Marines

The fundamental challenge for laser weapons is that, unlike in science fiction where lasers fly like bullets, a laser weapon in the real world has to stay focused for a long time, burning through the target the way a child might use a magnifying glass on a beetle. For the kid, the insect is easily trapped. For the laser, it has to stay focused on a moving target while burning it. This burning need not destroy the missile completely. Instead, by targeting a stabilizing fin, the missile may simply be disabled.

There's still considerable debate about how much laser is needed to disable what kind of missile, and whether it's even possible for lasers to destroy missiles. A report by the Congressional Research Office found several competing claims.

Laser Power Levels Congressional Research Service

The Future Of Lasers

Because the technology is still in development, we don't yet know how strong lasers will get, or if they'll be able to do all that they promise. But here's how those promises look:

From Boeing, this video demonstration of HEL MD is all about targeting and tracking flying objects with lasers:

 

Lockheed demonstrated a laser against a tethered rocket, and the video below shows how that laser burnt through the missile's head, blowing it up:

The Airborne Laser Testbed was a project by Boeing and Northrop Grumman for the U.S. Missile Defense Agency, which put a giant laser on the nose of a 747. Now canceled, it was plagued by high cost and repeated failures that undermined its promise of safety through superior laser power. Here it is in action:

In this concept video, BAE puts their future laser on a concept plane, firmly placing the laser as a technology of tomorrow, with shooting down airborne missiles just one of the many new things about future aircraft.

 








U.K. Supermarket To Run On Electricity Made From Its Own Rotting Food

Tue, 07/22/2014 - 09:16

An Anaerobic Digestion Plant City of Lincoln, Nebraska

One U.K. grocery store plans to power itself using biogas harvested from its own unsold, rotting produce. Yum.

A Sainsbury's store in Cannock in central England is getting access to anaerobic digesters. The store plans to use electricity solely from the digesters, taking no electricity from the U.K.'s national power grid, which is fed by a combination of coal, natural gas, nuclear power plants and other sources. Sainsbury's will even sell any excess electricity it makes back to the grid.

The Cannock Sainsbury's will be the first U.K. store to stop using U.K. grid electricity, the BBC reports. While we've never heard of a big U.S. store doing exactly that, U.S. grocery-store chain Kroger is supposed to have an anaerobic digester that provides more than 20 percent of the electricity needs of its Compton distribution center. And U.S. cities and states have recently planned anaerobic digester systems to take discarded food.

What happens in an anaerobic digester is 'what happens inside a cow's stomach after dinner.'

Here's how the Sainsbury's system will work. Food waste from many Sainsbury's stores will get trucked to a central depot. (One store doesn't make enough waste to power itself, so running the Cannock Sainsbury's actually requires waste from several.) From the depot, a waste-management company called Biffa will truck the waste to its Cannock plant.

What happens at Biffa's Cannock anaerobic digester is "what happens inside a cow's stomach after dinner," as this Ohio State University presentation puts it. The food goes into oxygen-free tanks with particular bacteria species inside that thrive without oxygen. Those bacteria break down the food in many steps; during the last step, bacteria produce primarily carbon dioxide and methane gas.

The Biffa plant separates the methane from the carbon dioxide, then uses the resulting biomethane just like natural gas mined from the ground to produce electricity. A 1.5-kilometer-long cable carries the electricity back to the Cannock Sainsbury's store.

Anaerobic digestion does have some drawbacks. It produces some solid and liquid wastes called the digestate. Some of the digestate can be used as fertilizer, but then you have to make sure you have customers for fertilizers nearby (i.e., farmers). Anaerobic digestion is also considered a less favored way of dealing with excess food. From an environmental standpoint, it's better to chop food up into deli salad, give it away to charities, or send it to animal feed. But if there's some food you can't avoid throwing away, anaerobic digestion is a great to take care of it.

P.S.P.S. (Popular Science Postscript): How can a process that produces carbon dioxide, a greenhouse gas, help reduce global warming? The explanation is a bit academic, but we love you for asking.

The carbon dioxide released from recently dead plants—whether you burn those plants, or stick 'em in a digester—isn't always considered as contributing to global warming. That's because in the natural cycle of things, the next generation of plants should take up the carbon dioxide released by the previous generation of dead plants, so long as there's a new plant grown for every dead plant digested or burned. That's the case for crops, which are plentifully regrown. On the other hand, fossil fuel-produced carbon dioxide is considered different because that CO2 would have stayed in the ground, had a human not dug it up and burned it.








Welcome To The Lab Of An Apollo Computer Anatomist

Mon, 07/21/2014 - 16:00

Blanche in her workshop. Photograph by Ray Lego

Fran Blanche’s workshop is more than a place to unwind. It’s home. “I put a bed in my office,” she says. Her fashion business is downstairs; upstairs is a music studio and a laboratory with 30 years’ worth of tools. A private collector recently asked Blanche to study part of his Apollo-era Launch Vehicle Digital Computer (LVDC), which NASA designed to fly a Saturn V rocket. “All modern boards would come to emulate it,” Blanche says. “Trouble is, there’s no information about how it was constructed.” 

Blanche's workshop in detail. Photograph by Fran Blanche

1) Tektronix 564B oscilloscope. Blanche owns two, and they help her examine DC- and audio-frequency signals.

2) Articulated dental-exam lamp. Designed in the 1940s, the lamp has a tightly focused beam that gives Blanche a clear view of a project from any angle.

3) Homemade adjustable DC-power supply. Whatever current and voltage a project requires, Blanche’s custom-built device can usually provide it.

4) Heathkit 5-watt resistor substitution box. No schematic is perfect. This device helps test various resistances in a circuit before installing the real deal.

5) 25-watt Weller soldering iron. “I have used this iron since 1978, and it has never failed,” says Blanche.

One of LVDC's page-assembly boards. Photograph by Fran Blanche

Saturn vs. LVDC: The launch-computer assembly could autopilot Apollo’s 363-foot-tall, 6.2-million-pound Saturn V rockets. Dozens of page-assembly boards like this one comprised each of the LVDC’s three computers. By carefully dissecting a board, Blanche uncovers its components and construction methods.

This article originally appeared in the August 2014 issue of Popular Science.








Eating Poo Helps Packrats Digest Toxic Plants

Mon, 07/21/2014 - 15:39

A desert woodrat Kevin Kohl, University of Utah

Desert woodrats are picky, but not in the way you might expect: several woodrat populations in the U.S. Southwest specifically eat a type of highly toxic creosote bush. Another group eats juniper, which is also toxic to many animals. This gives the woodrats (Neotoma lepida) a nice niche, allowing them to dine on a plant that others avoid. But how do they do it? A new study suggests that the microbes in their gut break down the toxic chemicals in the plants, which had been hypothesized but not clearly shown until now. 

To determine whether microbes help digest creosote, the scientists performed a variety of experiments. In one test, they found that packrats (as the animals are also known) fed creosote had much higher levels of bacteria thought to be involved in breaking down the plant's secondary chemicals, whereas those fed rabbit food did not--showing that diet influenced the makeup of gut microbiota. Then they fed two groups of the animals antibiotics, killing off many of their gut microbes. Animals that were fed creosote stopped eating the plant, and lost weight, whereas animals given rabbit food (devoid of toxins) seemed to do just fine, and didn't lose weight.

But it gets better. Packrats regularly feed on other animals' droppings in the wild, and with that in mind, the scientists fed a group of juniper-eating packrats a mixture of rabbit food and feces from creosote-eaters. These animals apparently developed the ability to break down the plant, compared to those just fed rabbit food, who couldn't subsequently eat the toxic plant.

All this work with toxic plants, poo and packrats has wider implications than you might imagine, however. It may be possible, for example, to help livestock feed on toxic plants like juniper, which is spreading throughout the Southwest, or help raise cattle in places where noxious weeds often hurt rancher's productivity. You could, presumably, give the cattle microbes from others that have become accustomed to eating these plants, or perhaps even use bacteria found in the droppings of other animals (here's looking at you, packrats). This kind of intervention, roughly equivalent to a "fecal transplant"--in which poop is transferred from one animal to another, and which has seen growing popularity amongst humans--could also possibly help in re-introducing endangered animals back into their natural environment, since breeding in the lab can cause the animals to lose microbes necessary for digesting certain toxic plant compounds found in the wild.

Eating poo has never sounded so promising.

The study was published this week in the journal Ecology Letters, and authored by researcher Kevin Kohl and colleagues at the University of Utah.


Ask Anything: Can Humans Smell Fear?

Mon, 07/21/2014 - 12:41

Illustrations by Jason Schneider

If humans can indeed smell fear they wouldn’t be unusual in the animal kingdom. Sea anemones, earthworms, minnows, fruit flies, rats, mice, and deer, among others, have all been shown to signal unease through odor. Some responses are even more overt. For example, the offspring of one bird species vomits up a pungent, orange liquid when frightened by a predator; if a parent catches a whiff, it becomes warier in the nest. 

From an evolutionary perspective, a silent signal makes sense. “If you find yourself in a fearful situation, you might want your cohorts to know about it, but without calling attention to yourself by screaming or jumping around,” says Charles J. Wysocki, of the Monell Chemical Senses Center in Philadelphia. The same could hold true for humans. “Primates have become much more visual creatures [over time],” he says, “and I suspect that smell in general, including the perception of the fearful notes, have taken second place. But they’re still there.”

There’s only modest evidence for a smell of fear in people, though. No one has yet found a molecule in human sweat that corresponds to our level of anxiety. Several labs have tried to measure the effects of sniffing someone else’s fear-inspired body odor. First the scientists show people scary movies, and then they collect the subjects’ sweat from cotton pads placed in their armpits. When other people smell the cotton, they respond in subtle and unconscious ways. In one experiment, the smellers became more likely to judge ambiguous facial expressions in photographs as portraying fear. In another, they made fearful expressions of their own. A third found that fear-sniffing subjects blinked more forcefully and seemed more prone to being defensive.

These studies have some big problems. Sweat born from emotion does seem to have a different smell than sweat from exercise. But that doesn’t tell us whether fear-related sweat works differently from, say, happiness-related sweat or the sweat that comes from sexual arousal. “We’re using very crude techniques to study this,” says Denise Chen, a pioneer in this field at the Baylor College of Medicine. Among the limitations of the work is the fact that emotions can be hard to regulate in the lab. “It’s very easy to scare people,” she says, “but it’s not so easy to make them happy.”

Hygiene products pose another problem. The researchers must find subjects who are willing to forgo deodorant for several days before each study. “That’s hard to do in this country because people are so hygiene-conscious,” Chen says. It also raises the question of whether any of this research would even matter in a real-world setting. Given all the fragrances we dab onto our bodies, any signals that sweat might contain would be undetectable.

Or maybe not. Wysocki says there’s evidence that certain people can detect body odor even when masked. He tested about 40 common compounds used to cover smells and arrived at a surprising result. “It’s fairly easy to block the body odor of women in the noses of men,” he says. “But when it came to women, only two of the [masking] compounds were effective.”

This article originally appeared in the August 2014 issue of Popular Science.