Monday, December 04, 2017

NEWS POST(S): NASA’s Voyager Spacecraft Still Reaching For The Stars After 40 Years

An artist concept depicting one of the twin Voyager spacecraft. Humanity’s farthest and longest-lived spacecraft are celebrating 40 years in August and September 2017. Credits: NASA
Humanity’s farthest and longest-lived spacecraft, Voyager 1 and 2, achieve 40 years of operation and exploration this August and September. Despite their vast distance, they continue to communicate with NASA daily, still probing the final frontier.

Their story has not only impacted generations of current and future scientists and engineers, but also Earth’s culture, including film, art and music. Each spacecraft carries a Golden Record of Earth sounds, pictures and messages. Since the spacecraft could last billions of years, these circular time capsules could one day be the only traces of human civilization.

“I believe that few missions can ever match the achievements of the Voyager spacecraft during their four decades of exploration,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate (SMD) at NASA Headquarters. “They have educated us to the unknown wonders of the universe and truly inspired humanity to continue to explore our solar system and beyond.”

The Voyagers have set numerous records in their unparalleled journeys. In 2012, Voyager 1, which launched on Sept. 5, 1977, became the only spacecraft to have entered interstellar space. Voyager 2, launched on Aug. 20, 1977, is the only spacecraft to have flown by all four outer planets – Jupiter, Saturn, Uranus and Neptune. Their numerous planetary encounters include discovering the first active volcanoes beyond Earth, on Jupiter’s moon Io; hints of a subsurface ocean on Jupiter’s moon Europa; the most Earth-like atmosphere in the solar system, on Saturn’s moon Titan; the jumbled-up, icy moon Miranda at Uranus; and icy-cold geysers on Neptune's moon Triton.

Though the spacecraft have left the planets far behind – and neither will come remotely close to another star for 40,000 years – the two probes still send back observations about conditions where our Sun's influence diminishes and interstellar space begins.

Voyager 1, now almost 13 billion miles from Earth, travels through interstellar space northward out of the plane of the planets. The probe has informed researchers that cosmic rays, atomic nuclei accelerated to nearly the speed of light, are as much as four times more abundant in interstellar space than in the vicinity of Earth. This means the heliosphere, the bubble-like volume containing our solar system's planets and solar wind, effectively acts as a radiation shield for the planets. Voyager 1 also hinted that the magnetic field of the local interstellar medium is wrapped around the heliosphere.

Voyager 2, now almost 11 billion miles from Earth, travels south and is expected to enter interstellar space in the next few years. The different locations of the two Voyagers allow scientists to compare right now two regions of space where the heliosphere interacts with the surrounding interstellar medium using instruments that measure charged particles, magnetic fields, low-frequency radio waves and solar wind plasma. Once Voyager 2 crosses into the interstellar medium, they will also be able to sample the medium from two different locations simultaneously.

"None of us knew, when we launched 40 years ago, that anything would still be working, and continuing on this pioneering journey," said Ed Stone, Voyager project scientist based at Caltech in Pasadena, California. "The most exciting thing they find in the next five years is likely to be something that we didn't know was out there to be discovered." 

The twin Voyagers have been cosmic overachievers, thanks to the foresight of mission designers. By preparing for the radiation environment at Jupiter, the harshest of all planets in our solar system, the spacecraft were well equipped for their subsequent journeys. Both Voyagers are equipped with long-lasting power supplies, as well as redundant systems that allow the spacecraft to switch to backup systems autonomously when necessary. Each Voyager carries three radioisotope thermoelectric generators, devices that use the heat energy generated from the decay of plutonium-238 – only half of it will be gone after 88 years.

Space is almost empty, so the Voyagers are not at a significant level of risk of bombardment by large objects. However, Voyager 1's interstellar space environment is not a complete void. It’s filled with clouds of dilute material remaining from stars that exploded as supernovae millions of years ago. This material doesn't pose a danger to the spacecraft, but is a key part of the environment that the Voyager mission is helping scientists study and characterize. 

Because the Voyagers' power decreases by four watts per year, engineers are learning how to operate the spacecraft under ever-tighter power constraints. And to maximize the Voyagers' life spans, they also have to consult documents written decades earlier describing commands and software, in addition to the expertise of former Voyager engineers.

"The technology is many generations old, and it takes someone with 1970s design experience to understand how the spacecraft operate and what updates can be made to permit them to continue operating today and into the future," said Suzanne Dodd, Voyager project manager based at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

Team members estimate they will have to turn off the last science instrument by 2030. However, even after the spacecraft go silent, they’ll continue on their trajectories at their present speed of more than 30,000 mph (48,280 kilometers per hour), completing an orbit within the Milky Way every 225 million years.

The Voyager spacecraft were built by JPL, which continues to operate both. The Voyager missions are part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of SMD.

NASA's Voyager 1 spacecraft launched atop its Titan/Centaur-6 launch vehicle from the Kennedy Space Centre Launch Complex in Florida on September 5, 1977, at 8:56 a.m. local time. Image Credit: NASA
NASA Successfully Fires Voyager 1 Thrusters After 37 Years
NASA's Voyager 1 spacecraft -- cruising interstellar space billions of miles from Earth -- was back on the right track Friday thanks to thrusters that were fired up for the first time in 37 years.

The unmanned spaceship was launched along with its twin, Voyager 2, more than 40 years ago to explore the outer planets of our solar system, traveling further than any human-made object in history. But after decades of operation, the "attitude control thrusters" that turn the spacecraft by firing tiny "puffs" had degraded. The small adjustments are needed to turn Voyager's antenna toward Earth, allowing it to continue sending communications.

"At 13 billion miles from Earth, there's no mechanic shop nearby to get a tune-up," NASA said in a news release.

Experts at the agency's Jet Propulsion Laboratory in California decided to turn to four backup thrusters that were last used on November 8, 1980.

"The Voyager flight team dug up decades-old data and examined the software that was coded in an outdated assembler language, to make sure we could safely test the thrusters," said Chris Jones, chief engineer at JPL.

The engineers fired up the thrusters on Tuesday and tested their ability to turn Voyager using 10-millisecond pulses. Then they waited 19 hours, 35 minutes for the test results to arrive at an antenna in Goldstone, California.

Turns out the thrusters worked just fine. "The Voyager team got more excited each time with each milestone in the thruster test. The mood was one of relief, joy and incredulity after witnessing these well-rested thrusters pick up the baton as if no time had passed at all," said Todd Barber, a JPL propulsion engineer.

Being able to use the backup thrusters means the lifespan of Voyager 1 has been extended by two or three years, added Suzanne Dodd, project manager for Voyager.

NASA plans to switch over to the formerly dormant thrusters in January. They will likely also conduct similar tests on the backup thrusters on Voyager 2.

Scientists still hear from the Voyager spacecraft daily, and expect to get data for about another decade. Astronomy textbooks were rewritten on a wide scale thanks to the Voyager spacecraft, which zoomed past Jupiter, Saturn, Neptune and Uranus.

The plutonium-powered spaceships will continue until they finally run out of fuel, and will then orbit in the center of the Milky Way galaxy.

Originally published on NASA and DAILY MAIL UK/AFP WIRES

Tuesday, November 28, 2017

GUEST BLOG POST: Creativity In The Digital Age — Laura Otis

Tangerine (2016) director and co-producer, Sean Baker (R), and Star Mya Taylor (C) Image credit - Zimbio
Synopsis
Smart phones are changing our understanding of creativity.

Yesterday (November 01, 2016) in a Berlin museum, a guard called my attention to a special picture. People were streaming in to see the Spanish Siglo de Oro exhibit, but few were studying the museum’s glorious collection, and he and I stood alone in a room of 15th-century Flemish paintings. The one he loved portrayed an old man wearing a thin stole of fox-fur. “Look at the fur,” he said. The little-known artist had painted it in such detail, it looked as though it would tickle my cheek. With infinitely fine lines, he had turned a two-dimensional surface into an illusion of floating softness.

The guard and I spoke about how long the artist must have studied to learn his technique. He must have started as an apprentice, cleaning brushes, and at some point he would have been allowed to paint feet. Only after decades of observation and practice could he have become a master.

As psychologists such as Mark Freeman and Mihaly Csikszentmihalyi have shown, no one becomes an artistic genius alone (Freeman 1993; Csikszentmihalyi 1996). Popular myths depict artists as rebels who succeed despite social forces, but that is not what the data show. Artists have to learn the rules of their domains before they can break them, and their innovations must be accepted as valuable by experts in their fields (Csikszenhimihalyi 1996, 27). As Freeman’s interviews with artists have revealed, “It is not quite right to say that creativity is affected by social conditions. Instead, it would seem more appropriate to say that creativity is constituted through those conditions” (Freeman 1993, 12). The painter of the fox-fur had talent, and he probably wanted to create art. But that talent would never have bloomed into brilliance without the apprenticeship his Flemish culture allowed.

The museum guard wanted to discuss more than painting, and I shrank when he spoke of young people’s unwillingness to work. According to a friend of his who taught high school, only three in a hundred students nowadays want to learn. The others are all playing with their smart phones. For a minute I empathized with him. I turned 55 yesterday, and I know the frustration of dodging zombies who walk staring into palm-sized boxes and expect the world to make way for them. What do they see that’s more fascinating than the people around them and the sky above? But my students with smart phones are brilliant, and no one could work harder than they. If young people who won’t learn constitute a threat, what about old people who won't learn?

The making of Tangerine is a story about the rarity of the planets aligning — for the actors, the filmmaker and the startup company, Moondog Labs, now dealing with a heavy demand for the adapter lens Baker used. To make Tangerine, his fifth feature film, Baker used two iPhone 5s’s, one 32G and one 64G. He used steadicam riggings because the light weight of the iPhone can pick up even the slightest shake. Most of the film was shot on the go, including scenes shot from the back of a moving motor scooter. A third camera was purchased but never used because it produced grainier video than the other two, Baker said. An anamorphic adaptor lens by Moondog Labs gave the movie Tangerine a cinematic feel. Photo credit: Cult of Mac
I told the guard that people could be creative with smart phones, an idea he didn’t accept. The marvelously daring film Tangerine was shot on an iPhone, and one can be active or passive with digital technology just as one can be active or passive with a pen and paper. Thinking that people stare at their smartphones because they’re interested in phones is like thinking that scientists study Drosophila genetics because they’re interested in fruit-flies. Digital devices offer views into the way the world works, and they invite rather than stifle creativity.

With all the warnings about what digital technology is doing to human brains, there has been less talk about what we’ve gained from it. If one thinks of a creator as a bounded individual, artistry remains more limited than if one thinks of human-machine networks or creative groups. The painting the museum guard admired emerged as the work of partnerships and tools: the person who cooked the artist’s meals; the person who taught him to paint; and the brushes, pigments, and canvas that constituted the technology of his time.

Creativity must be nourished and challenged, and it thrives because of cultures and technologies, not in spite of them. “The basis of art is truth,” said fiction-writer Flannery O’Connor, and it takes courage, patience, and overwhelming work to render truth in a form that engages many people (O’Connor 65). I regard it as equally courageous to shoot a feature-length film on an iPhone and to spend months painting fox-hairs so that a viewer can imagine them against her skin. As artistic creators, Tangerine director and co-producer Sean Baker and the 15th-century Flemish painter might not be as different as they seem. By studying the works of artists they admired and finding the support they needed, both created works that make their viewers feel. I left the museum guard alone with his painting, an old man contemplating an old man, hoping that artists born today would have the perseverance to create such beauty.

Works Cited
Baker, Sean S. Tangerine. 2016
Csikszentmihalyi, Mihaly. Creativity: Flow and the Psychology of Discovery and Invention. New York: Harper Collins, 1996.
Freeman, Mark. Finding the Muse: A Sociopsychological Inquiry into the Conditions of Artistic Creativity. Cambridge, UK: Cambridge University Press, 1993.
O’Connor, Flannery. “The Nature and Aim of Fiction.” In Mysteries and Manners: Occasional Prose, Selected and Edited by Sally and Robert Fitzgerald. New York: Farrar, Straus & Giroux.

This article was originally published in Psychology Today

Laura Otis, Ph.D., is a professor of English at Emory University, where she teaches interdisciplinary courses on literature, neuroscience, cognitive science, and medicine. She is the author of Rethinking Thought.

NEWS POST: The ‘Unhackable’ Quantum Messages That Could Stop Cyber Criminals From Using Super Computers To Steal Data

Illustrative hacker image via Shutterstock
Scientists have created a high-speed encryption system to stop hackers. It is based on an existing technique called quantum key distribution. The new technique transmits data 5-10 times faster than other methods

A new high speed encryption system promises to stop hackers using the next super
computers from stealing data.


Recent advances in quantum computers may soon give hackers access to machines powerful enough to crack even the toughest of standard internet security codes.

This will enable them to break codes and access any online data making all systems from medical records to bank transactions vulnerable to attack.

But scientists are using the same strange properties that drive quantum computers to create hack-proof forms of quantum data encryption.

The new system, developed by researchers from Ohio State University, is capable of creating and distributing encryption codes at megabit-per-second rates, which is five to 10 times faster than existing methods.

And these quantum encryption techniques are secure from common attacks, even in the face of equipment flaws that could open up leaks.

Professor Daniel Gauthier, an author of the study, said: 'We are now likely to have a functioning quantum computer that might be able to start breaking the existing cryptographic codes in the near future.

'We really need to be thinking hard now of different techniques that we could use for trying to secure the internet.'

When we buy online, make a bank transaction or share data like medical records, ciphers called encryption keys turn the data so it cannot be read. Personal information sent over the web is first scrambled using one of these keys, and then unscrambled by the receiver using the same key.

But for this system to work, both parties must have access to the same key, and it must be kept secret.
The new system, developed by researchers from Ohio State University, is capable of creating and distributing encryption codes at megabit-per-second rates, which is five to 10 times faster than existing methods (stock image)
Quantum key distribution (QKD) takes advantage of one of the fundamental properties of
quantum mechanics - measuring tiny bits of matter like electrons or photons automatically changes their properties - to exchange keys in a way that immediately alerts both parties to the existence of a security breach.

Though QKD was first theorized in 1984 and implemented shortly thereafter, the technologies to support its wide-scale use are only now coming online.

Companies in Europe now sell laser-based systems for QKD, and in a highly-publicised event last summer, China used a satellite to send a quantum key to two land-based stations located 1,200 km apart.

But PhD candidate, Nurul Taimur Islam, explained the problem with many of these systems is that they can only transmit keys at relatively low rates - between tens to hundreds of kilobits per second - which are too slow for most practical uses on the internet.

He said: 'At these rates, quantum-secure encryption systems cannot support some basic daily tasks, such as hosting an encrypted telephone call or video streaming.'
Like many QKD systems, Mr Islam's key transmitter uses a weakened laser to encode information on individual photons of light.

But they found a way to pack more information onto each photon, making their technique faster.

By adjusting the time at which the photon is released, and a property of the photon called the phase, their system can encode two bits of information per photon instead of one.

This trick, paired with high-speed detectors powers their system to transmit keys five to 10 times faster than other methods.

Prof Gauthier said: 'It was changing these additional properties of the photon that allowed us to almost double the secure key rate that we were able to obtain if we hadn't done that.'

In a perfect world, QKD would be perfectly secure as any attempt to hack a key exchange would leave errors on the transmission that could be easily spotted by the receiver.

But real-world implementations of QKD require imperfect equipment, and these imperfections open up leaks that hackers can exploit.

The researchers carefully characterized the limitations of each piece of equipment they used.

Mr Islam said: 'We wanted to identify every experimental flaw in the system, and include these flaws in the theory so that we could ensure our system is secure and there is no potential side-channel attack.

'All of this equipment, apart from the single-photon detectors, exist in the telecommunications industry, and with some engineering we could probably fit the entire transmitter and receiver in a box as big as a computer CPU.'


Companies in Europe now sell laser-based systems
for QKD, and in a highly-publicised event  last summer,
China used a satellite to send a quantum key to two
 land-based stations located 1,200 km apart
(artist's impression pictured)

Originally published on DAILY MAIL SCI & TECH