Nobel Prize Awarded for Detection of Gravity Waves

Three share award for building LIGO and hearing black holes collide

Photo: Molly Riley/AFP/Getty Images
Rainer Weiss, Barry Barish, and Kip Thorne, have been awarded the Nobel Physics Prize 2017 for their gravitational wave work.
The three men who won this year’s Nobel Prize in physics opened up a new field of science and helped prove Einstein correct by detecting gravitational waves from a pair of colliding black holes.

Rainer Weiss, a physicist from the Massachusetts Institute of Technology, will receive half the prize, while California Institute of Technology physicists Barry C. Barish and Kip S. Thorne will spilt the other half. The three were awarded for conceiving and creating the Laser Interferometer Gravitational Wave Observatory, or LIGO.

LIGO consists of two facilities, one in Hanford, Wash., and one in Livingston, La. Each is made up of two 4-kilometer-long tunnels at right angles to each other. Scientists fire laser beams down each tunnel and measure their reflections. When a gravity wave passes through Earth, it compresses space by a small amount, like a ripple in a pond, and produces a tiny perturbation in the light. In September 2015, LIGO detected the ripple produced when two massive black holes spiraled into each other, 1.3 billion light years away.

Just last week, a sister detector in Italy called Virgo announced the discovery of another collision, the fourth reported so far. That was the first to be measured by three detectors—which allows scientists to locate the source in the sky and point other telescopes toward the event.

“It’s a new branch of science, gravitational wave astronomy,” says Sheldon Glashow, a professor of physics at Boston University, who himself won the Nobel in 1979 for contributions to the theory that two fundamental forces of physics, the weak nuclear force and the electromagnetic force, interacted.

Glashow says the Nobel committee did a good job of divvying up the prize, which totals 9 million Swedish krona, or roughly $1.1 million. “They recognized two of the pioneers of the search, together with the person who actually made it happen.”

Weiss and another scientist, Ron Drever of the University of Glasgow, had separately come up with the idea to use lasers to detect gravitational waves in the mid-1970s. Weiss and Thorne figured out how they might make a detector, and Drever joined them in the project. The group had trouble gaining funding from the National Science Foundation, and eventually Drever, who died this past March, was forced out of the project. Glashow says it wasn’t until Barish came in, in 1994, that the project finally went ahead. “NSF was about to cancel it, but then they said ‘Get Barry, and he’ll solve the problem,’” Glashow says.

Weiss, he says, was the one who figured out what kind of sensitivity such a detector would need to be able to detect gravitational waves. “He was the guy who knew what they needed. Barish was the guy who made it happen,” Glashow said. Thorne, meanwhile, was the evangelist, convincing scientists and the public that this was a worthwhile endeavor.

The 2015 detection recorded the merger of two black holes, one with 29 times the mass of the sun and the other with 36 times the sun’s mass. Glashow says that was surprising to physicists, who believed most ordinary black holes would be only two or three solar masses, except for the giant ones at the centers of galaxies, which can be thousands or millions of times as massive. Now, he says, scientists have to figure out what would produce these intermediate black holes.

LIGO is currently shut down, and the detectors are being upgraded to make them more sensitive. When they’re put back online, they should be able to detect events twice as far away, which means covering eight times the volume of space.

One project will involve trying to measure the polarization of cosmic background radiation, the signature left over from the Big Bang. That, says Glashow, could tell scientists something about the nature of primordial black holes formed near the beginning of the universe, about which they know very little. Measuring the polarization of the gravity waves produced by the collapse of black holes “tells you the tiny little details of Einstein’s theory,” he says.

And some people—not Glashow, he points out—think that gravitational studies will give hints about the existence of axions, theoretical particles that, if they exist, may help explain dark matter, one of the biggest mysteries in cosmology today.

Whatever LIGO and similar detectors find, they’re opening up a new field of science, Glashow says. “Every time we open a window—radio astronomy, x-ray astronomy—we find things we didn’t expect,” he says. With gravitational wave astronomy, “we’ve found the things we expected, but we’re beginning to find the things we didn’t expect.”

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More Teachers, Fewer 3D Printers: How to Improve K–12 Computer Science Education

Tech companies and the U.S. government recently pledged $500 million for STEM programs

Photo: iStockphoto
Last week, the Trump White House announced $200 million in federal funding to improve K–12 computer science education every year. The next day, tech leaders including Amazon, Facebook, Google, Microsoft, and Salesforce added another $300 million to the bag, spread over five years. The goal of that initiative is to support K–12 STEM education, focusing on computer science.

The need for basic computer science education has never been greater. Software and computers drive the economy, aiding mines and farms, as well as retail stores, banks, and healthcare. There are 500,000 computer science job openings in the U.S., spanning every industry and state. That’s more than 10 times the number of students who graduated with computer science degrees last year, according to the nonprofit Code.org, which has been working tirelessly to establish and expand CS access in schools.

The tech industry grumbles about the shortage of qualified workers. Yet fewer than half of American K–12 schools offer computer science classes, according to Code.org. That number goes up to around three-fourths of K–12 schools when you include CS exposure through after-school activities and clubs, according to a 2016 Google-Gallup report.

Newer data on high school Advanced Placement exams collected by College Board does show positive signs. The number of “AP Computer Science A” exam-takers more than doubled from 2012 to 2016, reaching more than 54,000 students. And another 40,000 students took the new “AP Computer Science Principles” exam introduced in 2017. But that’s still a small fraction of the 15.1 million students attending high school this year.

A vast majority of students, parents, and educators are interested in and highly value computer science, the Google-Gallup report found. But state policies and curricula are lagging. Ten states currently have K–12 computer science standards, and 10 others are working on them. Only 33 states count computer science courses toward high school graduation credit. Arkansas is the only state that has made K–12 CS education mandatory. Virginia and Rhode Island are on that path.

Getting to this point has taken three decades of tireless state-level advocacy from Code.org and the Association for Computing Machinery. And there’s still a long way to go. Many states treat CS as an elective rather than a core academic subject like math and chemistry. Plus, most state standards focus on basic computer skills, rather than understanding core computing concepts.

Ideal CS courses should teach computational thinking: logical thinking, abstraction, algorithmic expression, problem decomposition, stepwise fault isolation, and debugging. “Every 21st century citizen needs fluency in computational thinking,” says Ed Lazowska, a computer science professor at the University of Washington. “It is never too early to start learning this. Elementary school kids can and do learn it.”

In fact, it’s crucial to start early. Just like reading and math, starting in kindergarten and learning incrementally builds a foundation for logic, critical thinking, and creativity. These skills are difficult to catch-up on later. Plus, says Code.org’s Chief Academic Officer Pat Yongpradit, reaching students earlier helps get girls and minorities on board. “They build confidence and efficacy around their ability to do computer science,” he says. “You can avoid stereotypes or at least make them aware of them.”

Other countries are stepping up CS education efforts. Israel leads the world, according to a report by the Information Technology & Innovation Foundation (ITIF). Its curriculum emphasizes CS as a science instead of teaching only coding, and the nation has 16.2 times as many students on a per-capita basis as the U.S. taking rigorous high school computer science. The U.K. mandates CS for students aged 5 to 14, but is struggling to train all the teachers it needs. According to the ITIF, Australia, Finland, Denmark, and Singapore are reforming CS education by introducing it to primary school students, adding deep concepts to curricula, and training specialized teachers.

Addressing the teacher shortage should be the number one use for the new funds allocated by the Trump administration, says Mark Stehlik, a computer science professor at Carnegie Mellon University. A lack of qualified teachers is the biggest barrier to CS education in the U.S., he says, and he thinks the problem is going to get worse. An earlier generation of CS educators has started to retire, and he says younger CS graduates “aren’t going into education because they can make twice or more working in the software industry.”

One solution could be to expand the reach of each CS educator through online classes. But “online curricula aren’t going to save the day, especially for elementary and high school,” Stehlik says. “A motivated teacher who can inspire students and provide tailored feedback to them is the coin of the realm here.”

Where the money should not be spent? On hardware and equipment. Laptops, robots, and 3D printers are important, says Code.org’s Yongpradit, “but they don’t make a CS class. A trained teacher makes a CS class. So money should be focused on training teachers and offering robust curriculum.”

Corporations also need to take more seriously their responsibility to donate money and technology, and, perhaps more crucially, provide volunteers who can share their skills and knowledge with students. Some top tech firms like Microsoft already have programs that encourage employees to volunteer-teach high school courses, which typically means spending a couple hours a week delivering the class. But it would be more effective if those employees spent several days at the school, teaching students and also mentoring teachers.

This approach can be a win-win for everyone, Stehlik says: building community and social good in the short term, and in the long term, ensuring a workforce for the companies themselves.

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Clear As well as Unbiased Facts Regarding What Is A Drone? (Without All the Buzz).

 

 

A drone, likewise called an unmanned aerial lorry (UAV) as well as lots of other names, is a tool that will fly without the use of a pilot or any person on board. These ‘airplane’ could be regulated remotely making use of a remote gadget by a person standing on the ground or by using computer systems that are on-board. UAV’s at first were generally managed by someone on the ground yet as innovation has actually advanced, a growing number of airplane are being made with the purpose of being managed using on-board computer systems.

The concept of an unmanned airborne car can be mapped back to early in the twentieth century and were initially planned to be solely made use of for military goals yet have actually considering that located location in our daily lives. Reginald Denny, who was a preferred movie star as well as a devoted collection agency of version aircrafts was stated to create the very first remote piloted car in 1935. Given that this date, the airplane have been able to adjust to new modern technologies and can now be located with electronic cameras along with various other valuable extras. As a result of this, UAVs are used for policing, security work and monitoring as well as firefighting, they are also used by numerous business to look at hard to get to possessions such as piping as well as wirework including an extra layer of security as well as safety and security.

The increase in appeal of these gadgets has nevertheless, brought some downsides in addition to positives as brand-new rules and laws have had to be presented to manage the scenario. As the UAVs were getting more powerful as well as innovations were improving, it suggested that they could fly higher and also better far from the operator. This has actually led to some troubles with flight terminal disturbance throughout the globe. In 2014, South Africa announced that they had to tighten protection when it concerns prohibited flying in South African airspace. A year later on and also the US revealed that they were holding a meeting to discuss the needs of signing up an industrial drone.

In addition to the previously pointed out uses, drones are now likewise used for evaluating of plants, counting animals in a particular location, looking into a group amongst lots of others. Drones have actually taken care of to transform the manner in which numerous sectors are run as well as have additionally allowed numerous organisations to come to be much more effective. Drones have likewise helped to raise safety and security as well as contribute when it pertains to conserving lives. Forest fires as well as natural calamities can be monitored as well as the drone can be made use of to notify the pertinent authorities of anybody that is in difficulty as well as seeking assistance. The specific area of these occasions can likewise be located easily.

Drones have additionally end up being a hobby for lots of people around the globe. In the United States, entertainment use such a device is legal; nonetheless, the owner has to take some precautions when trying to fly. The aircraft needs to abide by particular standards that have been laid out; for instance, the tool could not be more than 55 pounds. The drone should additionally avoid being utilized in such a way that will certainly hinder airport procedures as well as if a drone is flown within 5 miles of a flight terminal, the airport terminals traffic control tower should be informeded beforehand.

How Experts Comb Satellite Images for Clues on North Korea’s Nuclear Tests

Satellite imagery analysts tracking North Korea’s nuclear program need more than just technical skills

Image: Planet
Satellite images of North Korean missile testing sites or nuclear reactor facilities can sometimes reveal smears of yellow or befuddling brown objects at certain times of the year. A casual armchair observer might suspect those patterns as indicating something nefarious. But they actually represent a mundane harvest practice—North Korean workers often dry out their corn harvest on pavement before putting the harvested crop into brown sacks.

Growing swarms of commercial satellites have provided new tools for both government spies and independent analysts to peek inside North Korea as the isolated “Hermit Kingdom” races to strengthen its arsenal of nuclear weapons. But the process of understanding satellite images of suspected North Korean missile or nuclear test sites is far from easy and requires more than just the latest satellite imaging technology. The best analysts need more than the skills to analyze near-infrared imagery or use mapping software—they must also tap into a wide swath of cultural and technical knowledge when trying to figure out what a particular satellite image can reveal about the secretive North Korean nuclear program.

“Satellite imagery interpretation is very interdisciplinary,” says Melissa Hanham, a senior research associate in the East Asia Nonproliferation Program at the Middlebury Institute of International Studies
(MIIS) at Monterey, Calif. “You have to be a little bit of an expert in everything, and you have to know your limits.”

Analysts have access to more satellite data than ever these days. Companies such as DigitalGlobe and Airbus have satellites capable of providing high-resolution images of ground objects as small as a third of a meter per pixel for commercial customers. Newer companies such as Planet have deployed constellations of dozens of smaller satellites with lower resolution capabilities around 3 meters per pixel. But the swarm of small satellites can capture more frequent images of locations in North Korea and elsewhere, which provides analysts a new tool for tracking a given site’s normal “pattern of life.”

Both increased access to daily satellite imagery and broad expertise on North Korea proved helpful in a 2016
Washington Post 
analysis by Hanham and her colleagues. Part of their analysis involved identifying corn piled along the access road leading to Panghyon Airbase in Kusong, North Korea, which represents an alternative missile test site for the regime. They were able to quickly rule out the idea that the brown sacks of corn might represent some mysterious equipment related to missile launches.

“While satellite imagery can give you the keys to the castle for a country that is closed off, there is also lots of room for error that context,
” says David Schmerler
, a research associate at MIIS.

The MIIS researchers used near-infrared satellite imagery to highlight some rather large burn scars left in the surrounding vegetation from two North Korean missile launch attempts that both went awry in October 2016. The sequence of before and after daily images was taken by a constellation of smaller satellites owned by Planet. (More recently, the publication 
38 North
 also made use of Planet’s daily satellite imagery to examine landslides resulting from North Korea’s sixth nuclear test.)

Technical and cultural knowledge go hand-in-hand, says
 Joseph Bermudez Jr., CEO and co-founder of KPA Associates, LLC and an analyst focused on North Korea’s defense and intelligence affairs and third-world ballistic missile development. 
He recalled being sent an image where someone thought they had spotted filled-in bomb craters left over from the Korean War. In fact, the circles represented traditional North Korean burial mounds where a circular area is cleared of grass for a mound placed in the middle

“There is an incredible range to what people are saying about satellite images of North Korea, and the vast majority of it is inaccurate,” Bermudez Jr. says. 
“The reason for that is satellite imagery interpretation is a skill that needs to be learned or taught—it needs experience behind it before you reach a level of accuracy that is acceptable.”

Bermudez Jr. usually begins his work by using color correction, sharpening the image and other processing tricks to make a satellite image look as good as possible for inspection. He also rotates the image to the “look angle” that represents the direction from which the original image was captured.

If he has a general idea of where in the image is the activity of most interest—such as a missile launchpad—he will zoom in and compare it with previous images showing the same site. But he also will have his computer software pan slowly across the entire image while zoomed in so that he can get a good look at everything in high detail.

Diverse life experiences and real-world skills among a team of analysts can also prove incredibly helpful. Bermudez Jr. learned about structures as a fireman paramedic earlier in his life. As a wilderness instructor, he also spent a lot of time walking around in the mountains and understanding natural drainage systems such as rivers and valleys. Other a
nalysts may know more about
 
building ships or railroad operations. Each analyst can then build “interpretation keys” based on his or her knowledge to share with others in examining satellite images.

Satellite imagery analysts also benefit from leaning on outside experts in other fields. Hanham has previously tapped into the expertise of a cousin who is a long-haul trucker and her microbiologist mom’s knowledge of lab equipment. “I’ve leveraged my family,” she says.

The community of satellite imagery analysts with deep expertise on North Korea is small. That limited amount of human expertise may prove a bottleneck at a time when commercial satellites continue to build ever-larger databases of imagery on North Korea. But increased use of image-recognition algorithms based on machine learning could help, Hanham says. She and her MIIS colleagues hope to eventually have more of a semi-automated process of identifying certain objects.

Commercial satellites may soon provide even broader space surveillance of North Korea with a wider array of imaging equipment. Some already make use of hyperspectral imaging capabilities that go beyond the visible light spectrum. Others have begun mounting synthetic aperture radar (SAR) that can provide 3D mapping of the Earth’s surface regardless of weather or nighttime conditions.

But regardless of the technologies, interpretation of satellite imagery still depends heavily on the human expertise factor. And experienced analysts are always careful to caution that satellite images represent just once piece of a much larger puzzle when it comes to gathering intelligence on North Korea.

“I’ve run into many cases where people who are imagery analysts believe they have absolute truth,” Bermudez Jr. says. “Satellite imagery is just a single point in time that can only tell you so much.”


Reporting for this story was supported by the Stanley Foundation.

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Laser Weapons Not Yet Ready for Missile Defense

Prototype laser weapons can zap drones from the sky. But they won’t protect the U.S. from North Korean nuclear missiles

Photo: John F. Williams/U.S. Navy
Laser weapons are on a roll. The U.S. Air Force, Army, Navy, Marines, and the Joint Improvised-Threat Defeat Organization are testing them. Plans include mounting them on Humvees to shoot down drones. You can see them destroy drones on YouTube. The Missile Defense Agency wants to test laser-equipped drones as a defense against North Korean missiles.

But don’t expect a quick fix. Laser weapons have come a long way in the past decade, but they’re still years away from defending against threats ranging from North Korean long-range nuclear missiles to short-range explosive-laden drones launched by ISIS.

The Pentagon has worried about nuclear strikes by “rogue states” since the end of the Cold War. In 1996 the Air Force began work on the Airborne Laser, a plan to put a megawatt-class chemically powered laser in a Boeing 747 that could patrol near potential nuclear threats, which then included Iran and Iraq as well as North Korea. In case of a launch, the laser would fire to catch the rocket at its most vulnerable stage, as it was boosting out of the atmosphere. Two massive ground-based lasers had already demonstrated megawatt output, and the Airborne Laser used a more advanced chemical system that promised to make a better weapon system.  

The Airborne Laser finally shot down target missiles in 2010, years late and far above its original budget, but that was too little and too late to avoid cancellation. The laser hadn’t delivered enough power far enough to shoot down a missile at the desired range. Logistics experts also found the practice of shoehorning dangerous chemical fuels within a laser into an airplane to be an insoluble problem.

When asked why he cancelled the program, Secretary of Defense Robert Gates said he knew nobody in the Pentagon “who thinks that this program should, or would, ever be operationally deployed. The reality is that you would need a laser something like 20 to 30 times more powerful than the chemical laser in the plane right now to be able to get any distance from the launch site to fire.” After a final series of tests, the Airborne Laser was scrapped in 2014.

The new generation of laser weapons are electrically powered solid-state types which can run on power from diesel generators. The Missile Defense Agency is considering that technology for laser-armed drones to defend against North Korean missiles. These drones would be much smaller than a 747, and carry a payload of 5,700 kilograms at 63,000 feet, compared to a 747’s payload of over 200,000 kilograms at 40,000 feet. The beam should go further at the higher altitude, but the planned prototype wouldn’t be ready until 2023.

Ground-based solid-state lasers have scored a series of successes. Last week, a 30-kilowatt Lockheed Martin ground-based system called ATHENA shot down five drones at the White Sands Missile Range. Earlier this year, Lockheed completed a 60-kilowatt version of the laser for the Army Space and Missile Defense Command in Huntsville, Ala. to test in a military truck. The Navy has tested a 30-kilowatt laser on the USS Ponce and plans ship-based tests of a 60-kilowatt laser.




But those lasers are testbeds, not weapons ready for field use. After testing several lasers with other anti-drone weapons at White Sands, the Joint Improvised-Threat Defeat Organization summed up the results as: “Bottom line: Most technologies still immature.” They had hopes for improvement, but said “threat targets were very resilient against damage.”

Shooting down enemy drones, such as those used by ISIS, with laser-equipped drones requires identifying a target drone’s most vulnerable spots, says Philip Coyle, Senior Science Fellow at The Center for Arms Control and Non-Proliferation. “Just hitting the fuselage of the drone might not do much damage. Much of the laser energy would bounce off, and even if the laser was powerful enough to burn a hole, the drone might be able to continue flying.” The engine or spots on the wing or tail might be more vulnerable. But that would vary among drones, and the Army would have to figure out what drones ISIS uses and where they are vulnerable.

“Another problem is that these laser defense systems are expensive, and we can’t afford to sprinkle them over a large area,” adds Coyle. A laser’s lethal range depends on its power and the vulnerability of potential targets, but is likely to be limited to a few miles.

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