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From KQED

White House Honors Two Techies for Making Programming Cool

Bay Area residents Carlos Bueno and Kimberly Bryant are helping to prepare kids to use programming concepts in daily life and work.

Tech Titans Join Forces on Internet Surveillance

More than 60 technology firms and other groups are urging the federal government to let companies disclose Patriot Act data requests.

Former Stanford President on Challenges Facing Higher Education

Former Stanford president Gerhard Casper joins us to discuss his new book "The Winds of Freedom," a collection of his speeches on the biggest challenges facing higher education. Casper was president of Stanford at a tumultuous time, and the speeches and commentary in his book explore academic freedom, campus diversity and the role of a research university in society and politics.

The Future of Virtual Reality

Virtual reality made headlines earlier this year when Facebook announced its plan to acquire Oculus VR, a company making virtual reality headsets. Industry experts say there could be an affordable headset on the market as early as next year. We'll examine the current developments in VR, and what this technology can achieve beyond gaming and entertainment. We'll also discuss potential drawbacks of this deeply immersive technology.

PBS NewsHour

How to land on a comet as it hurls through space

Five
         candidate sites were identified on Comet 67P/Churyumov-Gerasimenko during the Landing Site Selection Group meeting held 23–24
         August 2014. Image by ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Five candidate sites were identified on Comet 67P/Churyumov-Gerasimenko during the Landing Site Selection Group meeting last week. Image by ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Earlier this month, after a 10-year, 4-billion-mile journey, the Rosetta spacecraft entered orbit around the rubber-duck-shaped Comet 67P/Churyumov-Gerasimenko. Now it must land.

This is no helicopter landing. Putting the lander down onto the comet’s surface will require fantastically precise calculations, maneuvering and navigational skills and, once it’s released, six hours of what U.S. Rosetta project manager Art Chmielewski calls “patient stress.”

“The landing is so difficult,” he said. “So, so difficult. It’s definitely one of the hardest things humankind has ever done.” Imagine, he said, grabbing a mosquito by the wings. Except the mosquito is in New York, and you’re working the controls from Los Angeles.

It’s difficult because the comet is hurling through space at 36,000 mph. The spacecraft has to catch up with the comet, fly alongside it at exactly the same speed and then drop a lander the size of a washing machine onto an area just over half a square mile. (For perspective, the width of Central Park between Central Park West and Fifth Avenue is half a mile.) Unlike Earth or Mars, there’s no substantial atmosphere, just a thin layer of gas particles surrounding the comet’s nucleus called its “coma.” And whereas the Mars Curiosity lander plummeted at about 13,000 miles per hour, the Philae lander will float down at a speed closer to 20 centimeters per second, like a piece of paper floating to the ground.

science-wednesday

“It’s all about this moment of release and the precise calculation of where it’s going to drop,” Chmielewski said. “Once you release it, you have no control.”

Rosetta is now cruising at an altitude of roughly 60 miles — that’s the distance from the spacecraft to the surface of the comet. It is close enough that a quarter of the comet fills the full frame of its camera lens. Earlier photos showed the full comet from different angles. Like this:

Rosetta
         snapped this shot of Comet 67P/Churyumov-Gerasimenko from a distance of 177 miles on Aug. 3. Photo courtesy of the European
         Space Agency

Rosetta snapped this shot of Comet 67P/Churyumov-Gerasimenko from a distance of 177 miles on Aug. 3. Photo courtesy of the European Space Agency

And this:

Comet
         67P/Churyumov-Gerasimenko on Aug. 2. The image was taken by Rosetta’s OSIRIS wide-angle camera from a distance of about 342
         miles. Photo courtesy of the European Space Agency

Comet 67P/Churyumov-Gerasimenko on Aug. 2. The image was taken by Rosetta’s OSIRIS wide-angle camera from a distance of about 342 miles. Photo courtesy of the European Space Agency

This week, a team of 50 scientists, representing a range of countries, narrowed the landing site down to five possibilities. Choosing a landing site for a comet isn’t easy either. The site requires a flat terrain and the right amount of daylight for the landing. It must have enough sun to power the equipment’s solar panels. And then there are the conflicting needs of the mission’s team members.

Engineers want a spot that lacks any obstacles — boulders, for example — that might thwart the landing. Scientists, on the other hand, say that’s geologically boring, Chmielewski said. “They say, ‘We want crevasses, we want boulders, we want varied terrain.’ If you try to find a landing site that meets all of them, you get a headache.”

From NASA’s Jet Propulsion Laboratory on the requirements for a landing site:

“For each possible zone, important questions must be asked: Will the lander be able to maintain regular communications with Rosetta? How common are surface hazards such as large boulders, deep crevasses or steep slopes? Is there sufficient illumination for scientific operations and enough sunlight to recharge the lander’s batteries beyond its initial 64-hour lifetime without causing overheating?”

And from the European Space Agency’s Rosetta Mission Twitter feed:

 

The team plans to have each site “assessed and ranked” by Sept. 14. Rosetta’s lander Philae is slated to land in mid-November. Once there, it will dig up dirt, sample the soil, test its constituents and study the depth of dust, along with ice and water. Meanwhile, the orbiter will continue to chase the comet as its orbit nears the sun.

Earlier this month, Hari Sreenivasan talked to Mark McCaughrean, senior scientific advisor of the European Space Agency.

Comets, McCaughrean said, are “treasure chests of material left over from the birth of the solar system.” They contain dust, water and organic materials — “stuff that could be the origin of life.”

The lander’s research will teach us about the ingredients of the comet itself, but may also give clues to the formation of the solar system and to the “initial ingredients that became the sun and the planet and you and me,” Chmielewski said.

“This time,” McCaughrean said, “we’re going to watch this comet as it comes into the inner solar system, heats up, evolves, changes and gets dynamic — there’s going to be so many unexpected surprises.”

The post How to land on a comet as it hurls through space appeared first on PBS NewsHour.

Growing human tissue for mass-production

Scientists are attempting to grow human tissue on small computer chips. Video by Wyss Institute

Scientists working out of the University of California, Berkeley are trying to grow thin layers of human lung, liver and heart tissue on minuscule computer chips in an effort to reduce the delay between initial laboratory research and clinical trials.

By manipulating adult cells harvested from skin, the team has recreated the tissue of vital organs that might otherwise be difficult or dangerous to obtain from test subjects. Using these so-called “organoid chips” in lieu of people might give doctors the chance to further refine drug treatments both for their effectiveness and overall safety.

Similar research is being done at Harvard’s Wyss Institute, where “organs-on-a-chip” are used to conduct drug testing to treat Barth syndrome and other diseases.

In many ways, the human body is like a complex puzzle composed of more than 7,500 individual parts, which are generally grouped into 78 organs and 13 organ systems. These chips act like simplified puzzle pieces that, when assembled, can simulate the ways in which drugs affect both individual organs and the body as a whole.

These chips, however, typically lack the complexity of the full-grown human tissue. Moreover, their shelf lives are too short for long-term testing periods. Yet, these chips can still be of value to drug companies. Like traditional computer microchips, “organoid chips” are meant to be mass-produced, providing a massive pool of semi-living subjects on which multiple iterations of a drugs-in-development could be tested.

For every one drug that eventually reaches consumers, there are some 40,000 that do not because of the monumental costs associated with bringing drugs to market. Much of the costs, according to drug companies, is attributed to failed drug trials. Organoid chips, unlike individual human or animal test subjects, could be created uniformly, possibly eliminating many of the variables that complicate and slow down the testing and eventual approval process of experimental treatments.

The post Growing human tissue for mass-production appeared first on PBS NewsHour.

Changing glass into metal, with the help of lasers

Scientists at the Vienna University of Technology have been able to change the properties of quartz glass into metal
         for very brief moments using laser pulses. Image by Vienna University of Technology

Scientists at the Vienna University of Technology have been able to change the properties of quartz glass into metal for very brief moments using laser pulses. Image by Vienna University of Technology

Scientists at the Vienna University of Technology found a way to turn quartz glass into metal — if only for a split second.

Using quick laser pulses, the scientists are able to fundamentally change the electronic properties of the non-conducting quartz glass and allow the material to briefly behave as a metal and a conductor.

“The laser pulse is an extremely strong electric field, which has the power to dramatically change the electronic states in the quartz,” Georg Wachter, theoretical physicist at the Vienna University of Technology said. “The pulse can not only transfer energy to the electrons, it completely distorts the whole structure of possible electron states in the material.”

The change in state may be short, but the scientists believe that transistor technology can take advantage of that moment. Once the laser pulses are applied, the change in state from glass to metal is found to happen within femtoseconds — one millionth of one billionth of a second.

In the transistors we are using today, a large number of charge carriers moves during each switching operation, until a new equilibrium state is reached, and this takes some time. The situation is quite different when the material properties are changed by the laser pulse. Here, the switching process results from the change of the electronic structure and the ionization of atoms. “These effects are among the fastest known processes in solid state physics”, says [associate professor at the Vienna University of Technology] Christoph Lemell. Transistors usually work on a time scale of picoseconds (10^-12 seconds), laser pulses could switch electric currents a thousand times faster.

The post Changing glass into metal, with the help of lasers appeared first on PBS NewsHour.

California law orders kill-switch software in smartphones

Photo by Flickr user Blake Patterson

California Governor Jerry Brown signed a bill Monday mandating that all smartphones sold in the state are to be installed with a software that remotely clears the device of data. Photo by Flickr user Blake Patterson

In case of theft, residents of California will be able to remotely wipe their smartphone data with the push of a button.

This kill-switch functionality will be built into all smartphones sold in the “Golden State” manufactured after July 1, 2015. Governor Jerry Brown signed the legislation into law on Monday.

The bill, first introduced by Senator Mark Leno (D-San Francisco), is designed to help curtail cell phone theft. In addition to giving people the ability to protect their information, the kill-switch bill levies a civil penalty ranging between $500-$2,500 against anyone found to be selling stolen phones.

This feature, which is optional, is not universally supported.

Both the Electronic Frontier Foundation and the CTIA wireless industry  lobbying group have said that a number of third party applications already provide this functionality for most cellphones. In June, the EFF said that giving consumers easy access to data wiping capabilities could provide hackers with a vulnerable entry point to intercept private information.

Similar claims were made by a number of cellphone manufacturers and wireless carriers when the bill first passed through the Senate. Apple, AT&T, Google, and Verizon, who all stood to benefit financially from the sale of cellphone replacements and monthly insurance, reversed their opposition following questions about the ethics of their position.

The post California law orders kill-switch software in smartphones appeared first on PBS NewsHour.