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We live in a world where digital information is exploding. Some 90% of the world’s data was generated in the past two years. The obvious question is: how can we store it all?
In Nature Communications today, we, along with Richard Evans from CSIRO, show how we developed a new technique to enable the data capacity of a single DVD to increase from 4.7 gigabytes up to one petabyte (1,000 terabytes). This is equivalent of 10.6 years of compressed high-definition video or 50,000 full high-definition movies.
So how did we manage to achieve such a huge boost in data storage? First, we need to understand how data is stored on optical discs such as CDs and DVDs.
The basics of digital storage
Although optical discs are used to carry software, films, games, and private data, and have great advantages over other recording media in terms of cost, longevity and reliability, their low data storage capacity is their major limiting factor.
The operation of optical data storage is rather simple. When you burn a CD, for example, the information is transformed to strings of binary digits (0s and 1s, also called bits). Each bit is then laser “burned” into the disc, using a single beam of light, in the form of dots.
The storage capacity of optical discs is mainly limited by the physical dimensions of the dots. But as there’s a limit to the size of the disc as well as the size of the dots, many current methods of data storage, such as DVDs and Blu-ray discs, continue to have low level storage density.
To get around this, we had to look at light’s fundamental laws.
Circumnavigating Abbe’s limit
In 1873, German physicist Ernst Abbe published a law that limits the width of light beams.
On the basis of this law, the diameter of a spot of light, obtained by focusing a light beam through a lens, cannot be smaller than half its wavelength – around 500 nanometres (500 billionths of a metre) for visible light.
And while this law plays a huge role in modern optical microscopy, it also sets up a barrier for any efforts from researchers to produce extremely small dots – in the nanometre region – to use as binary bits.
In our study, we showed how to break this fundamental limit by using a two-light-beam method, with different colours, for recording onto discs instead of the conventional single-light-beam method.
Both beams must abide by Abbe’s law, so they cannot produce smaller dots individually. But we gave the two beams different functions:
The first beam (red, in the figure right) has a round shape, and is used to activate the recording. We called it the writing beam
The second beam – the purple donut-shape – plays an anti-recording function, inhibiting the function of the writing beam
The two beams were then overlapped. As the second beam cancelled out the first in its donut ring, the recording process was tightly confined to the centre of the writing beam.
This new technique produces an effective focal spot of nine nanometres – or one ten thousandth the diameter of a human hair.
The technique, in practical terms
Our work will greatly impact the development of super-compact devices as well as nanoscience and nanotechnology research.
The exceptional penetration feature of light beams allow for 3D recording or fabrication, which can dramatically increase the data storage – the number of dots – on a single optical device.
The technique is also cost-effective and portable, as only conventional optical and laser elements are used, and allows for the development of optical data storage with long life and low energy consumption, which could be an ideal platform for a Big Data centre.
As the rate of information generated worldwide continues to accelerate, the aim of more storage capacity in compact devices will continue. Our breakthrough has put that target within our reach. [Reply]
How about a space-based telescope, that could be accessible to the general public? A mini Hubble type telescope, that you could take a picture of a galaxy a billion light years away, directly from your smartphone?
Meet ARKYD, the space telescope for EVERYONE.
This Kickstarter campaign has already raised over $1M, but more is needed.
Originally Posted by :
The Kickstarter campaign for Arkyd still has 10 days remaining. To keep the funds flowing, the group behind it has released several “stretch” goals if it can reach further milestones:
- $1.3 million: A ground station at an undisclosed “educational partner” that would double the download speed of data from the orbiting observatory.
Example of an orbital ‘selfie’ that Planetary Resources’ ARKYD telescope could provide to anyone who donates to their new Kickstarter campaign. Credit: Planetary Resources.
- $1.5 million: This goal, just released yesterday, is aimed at the more than 20,000 people who signed up for “space selfies” incentive where uploaded pictures are photographed on the telescope while it is in orbit. For this goal, “beta selfies” will be taken while the telescope is in the integration phase of the build.
- $1.7 million: The milestone will be announced if Arkyd reaches 15,000 backers. (It has more than 12,000 as of this writing.)
- $2 million: The telescope will hunt for alien planets. Planetary Resources added this goal last week following technical problems plaguing NASA’s Kepler space telescope that could derail the agency’s prolific planet finder.
Also, a hat-tip to NASA’s Peter Edmonds, who works in public affairs for the Chandra X-ray Observatory, for pointing out the campaign’s Kickstarter video in Klingon. Check it out below:
Deaf boy with auditory brain stem implant stunned after hearing dad for first time
A 3-year-old boy is hearing the world for the first time, thanks to an auditory brain stem implant.
"He likes sound," young Grayson's mom Nicole Clamp, said to CBS affiliate WBTV in Charlotte, N.C. "He enjoys the stimulus, the input. He's curious, and he definitely enjoys it."
Grayson Clamp was born without his cochlear nerves, or the auditory nerve that carries the sound signal from the cochlea in the inner ear to the brain. His parents tried giving him a cochlear implant, but it did not work.
They then enrolled Grayson in a research trial at University of North Carolina Hospitals in Chapel Hill, N.C. Three weeks ago, he became the first child in the U.S. to receive an auditory brain stem implant.
The procedure involves placing a microchip on the brain stem to bypass the cochlear nerves altogether. The person perceives and processes sound, which travel through tubes in his ear.
Dr. Craig Buchman, Grayson's head and neck surgeon at UNC, explained to CBSNews.com that the devices were made several years ago for adults who have tumors in their cochlear nerves, but it has never been approved for use in children in the United States.. While the implants were able to give back some hearing to the adults that received them, they were not as effective as cochlear implants.
However, Buchman's team's theory was that if the auditory brain stem implant was put in a young child, they may be better at processing the sounds.
"One of the reasons we really were interested in this study, children have enormous potential because of their brain plasticity," he said. "They have enormous potential to interpret sounds.... I don't know what he hears and how he's going to use it, but only time will tell."
Grayson was the first chosen because he had high cognitive abilities and used cued speech, a visual system based on phonetics used to communicate. That way, doctors could see if he was hearing anything and responding to sound stimuli.
When he heard his father calling him for the first time, his face lit up with shock. Buchman said he was pleased with Grayson's responses.
The child still has to go in for frequent checkups to fine tune the device in order to give him the best hearing possible.
"We don't know exactly what it's like for him," Nicole explained. "We don't know exactly what he hears. His brain is still trying organize itself to use sound."
In total, Buchman's team has evaluated 10 children who all have similar problems with missing nerves. Right now, they're limiting the study to younger children who don't have that many additional health or cognitive issues to see what the potential of the device is. If they are successful, they are hoping that older children who haven't learned how to speak because of their hearing problems may be given a chance to finally hear and talk.
As for Grayson, he's already benefiting from his new hearing abilities.
"It's been phenomenal for us," his father Len Clamp said to WBTV.
Click link for vid, the look on his face is AWESOME!!! [Reply]
Originally Posted by :
Alan Turing was born on 23 June, 1912, in London. His father was in the Indian Civil Service and Turing's parents lived in India until his father's retirement in 1926. Turing and his brother stayed with friends and relatives in England. Turing studied mathematics at Cambridge University, and subsequently taught there, working in the burgeoning world of quantum mechanics. It was at Cambridge that he developed the proof which states that automatic computation cannot solve all mathematical problems. This concept, also known as the Turing machine, is considered the basis for the modern theory of computation.
In 1936, Turing went to Princeton University in America, returning to England in 1938. He began to work secretly part-time for the British cryptanalytic department, the Government Code and Cypher School. On the outbreak of war he took up full-time work at its headquarters, Bletchley Park.
Here he played a vital role in deciphering the messages encrypted by the German Enigma machine, which provided vital intelligence for the Allies. He took the lead in a team that designed a machine known as a bombe that successfully decoded German messages. He became a well-known and rather eccentric figure at Bletchley.
After the war, Turing turned his thoughts to the development of a machine that would logically process information. He worked first for the National Physical Laboratory (1945-1948). His plans were dismissed by his colleagues and the lab lost out on being the first to design a digital computer. It is thought that Turing's blueprint would have secured them the honour, as his machine was capable of computation speeds higher than the others. In 1949, he went to Manchester University where he directed the computing laboratory and developed a body of work that helped to form the basis for the field of artificial intelligence. In 1951 he was elected a fellow of the Royal Society.
In 1952, Turing was arrested and tried for homosexuality, then a criminal offence. To avoid prison, he accepted injections of oestrogen for a year, which were intended to neutralise his libido. In that era, homosexuals were considered a security risk as they were open to blackmail. Turing's security clearance was withdrawn, meaning he could no longer work for GCHQ, the post-war successor to Bletchley Park.
For a spacecraft such as the Space Shuttle, the Mir, a Soyuz Capsule or the International Space Station to maintain an orbit around the Earth at relatively low altitudes (anywhere from approximately 175 to 575 kilometers [~95 to 310 nautical miles]) it must travel at approximately 32,500 km/hour (~17,500 nm/hr). At these altitudes and at this velocity it takes about 90 minutes to circle the Earth once, so every 45 minutes the astronauts and cosmonauts onboard see a sunrise and a sunset, a total of 16 each every 24 hours.
Originally Posted by Fish:
For a spacecraft such as the Space Shuttle, the Mir, a Soyuz Capsule or the International Space Station to maintain an orbit around the Earth at relatively low altitudes (anywhere from approximately 175 to 575 kilometers [~95 to 310 nautical miles]) it must travel at approximately 32,500 km/hour (~17,500 nm/hr). At these altitudes and at this velocity it takes about 90 minutes to circle the Earth once, so every 45 minutes the astronauts and cosmonauts onboard see a sunrise and a sunset, a total of 16 each every 24 hours.
I had someone tell me several years ago, that orbit at low altitude such as the ISS does, isn't technically an orbit at all. It's a controlled fall, with the speed sufficient to keep it continually falling "over the horizon", so to speak. While that didn't blow my mind, I gotta admit it popped a little.
I'm certain you know this stuff, so: was he full of shit? [Reply]
Originally Posted by chefsos:
I had someone tell me several years ago, that orbit at low altitude such as the ISS does, isn't technically an orbit at all. It's a controlled fall, with the speed sufficient to keep it continually falling "over the horizon", so to speak. While that didn't blow my mind, I gotta admit it popped a little.
I'm certain you know this stuff, so: was he full of shit?
That's absolutely correct. Orbit is nothing more than a controlled free fall where tangential acceleration overcomes gravity such that the object if falling but always stays at the same distance from the Earth. The space station is free falling toward the Earth at all times. But it never crashes into the Earth, because it's going so fast it always overshoots the horizon, like you said. It's going at the perfect speed so that it always stays at the same distance from the Earth, even though it's always technically falling.
It's really no different than a skydiver in free fall after jumping out of a plane, except that the atmosphere isn't continually resisting and pushing back against the person. Because the space station is higher than most of the atmosphere. So you don't have the "Wind rush" pushing back up against the falling body. That's why free fall in outer space looks more like floating. But if you would take away the resistance of the atmosphere in the case of a skydiver, it would look and feel exactly like a "Floating" astronaut in orbit.
Originally Posted by chefsos:
I had someone tell me several years ago, that orbit at low altitude such as the ISS does, isn't technically an orbit at all. It's a controlled fall, with the speed sufficient to keep it continually falling "over the horizon", so to speak. While that didn't blow my mind, I gotta admit it popped a little.
I'm certain you know this stuff, so: was he full of shit?
Well, I'd still label it as an orbit, but yes, the ISS and the space shuttles were/are moving at speeds sufficient to be falling toward Earth at all times, but the speed is such that they are falling past the horizon.
That's very different that other orbits, such as geosynchronous. [Reply]
Voyager’s prolonged journey into interstellar space took another dramatic turn when the intrepid space probe last summer passed into a bizarre and unanticipated cosmic hallway between the bubble of space under the sun’s influence and whatever lies beyond.
On the celestial highway since September 1977, the Voyager 1 probe soared past Jupiter and Saturn in 1979 and 1980, respectively, then ended up an a path that led toward interstellar space. Eventually, the spacecraft will get there, but exactly when that will happen -- and what else it may encounter before then -- is anybody’s guess.
“The results of the measurements from Voyager have been surprising us not just since last August, but for about the last 2.5 years,” astronomer Stamatios Krimigis, with Johns Hopkinds University’s Applied Physics Laboratory, told Discovery News.
Scientists thought Voyager 1 had finally passed beyond the heliosheath, the outermost region of space touched by the solar wind, a stream of charged particles continuously flowing the sun. On Aug. 25, 2012, Voyager suddenly found itself in an uncharted region of space, marked by the abrupt disappearance of particles from the sun and the sudden rise of particles emanating from interstellar space.
“As far as we could tell there was absolutely no solar material in the vicinity of the spacecraft and there hasn’t been since then. At the same time, the cosmic rays coming from outside the system started to increase. We all thought at the time that, by God, we were probably out of the solar system,” Krimigis said.
But there were two other puzzling bits of data that didn’t fit that scenario.
The first mystery was why the magnetic field Voyager measured was still aligned like the sun’s -- and even more perplexing, why the magnetic field suddenly strengthened.
Scientists had expected to see a different magnetic orientation once Voyager was in interstellar space.
The second conundrum was why the cosmic ray particles were not evenly distributed. The thinking was -- and is -- that cosmic rays, which emanate from distant supernova explosions all over the galaxy, should be uniformly spread out in every direction in interstellar space.
The best scientists can conclude is that Voyager is in some sort of foyer where particles from inside and outside the solar system can easily flow, but which is not quite yet in interstellar space. The rather unpoetic name they came up for this zone is the “heliosheath depletion region.”
“What we have is kind of a hybrid. The magnetic field still seems to be the solar magnetic field, not the interstellar magnetic field, so how do you define interstellar medium if that’s the case? If you really need to finally reach the case where both the magnetic field and the plasma are from other stars, then we’re still not there,” lead project scientist Ed Stone, with the California Institute of Technology in Pasadena, told Discovery News.
Scientists have no idea how much longer it will take Voyager to reach the next and presumably last leg of its journey into interstellar space, but the proverbial clock is ticking.
The spacecraft, which is powered by the slow decay of radioactive plutonium, will begin running out of power for its science instruments in 2020.
“By then, we would have shut off everything we can shut off other than the instruments and will have to turn off the first instrument. As time goes on, each year there are four watts less available, we’ll have to turn off the second instrument,” Stone said.
By 2025, Voyager, which was originally designed to last just five years, will be completely shut down.
Voyager is now about 122 times farther from the sun than Earth. At that distance it takes radio signals from Earth traveling at the speed of light 17 hours to reach the spacecraft.
A sister spacecraft called Voyager 2 is taking a different path toward interstellar space and has not yet encountered the panoply of twists and turns on the solar system’s exit ramp -- and it never may.
“Voyager 2 has seen exactly what the models predicted we would see, unlike Voyager 1, which didn’t,” Stone said.
The region where the heliosheath and interstellar space connect, where Voyager 1 is located, may be a local phenomenon, he added.
Originally Posted by Donger:
Well, I'd still label it as an orbit, but yes, the ISS and the space shuttles were/are moving at speeds sufficient to be falling toward Earth at all times, but the speed is such that they are falling past the horizon.
That's very different that other orbits, such as geosynchronous.
No, geosynchronous orbits obey the same satellite orbital gravitational/motion theories as any other orbiting object. The difference is that geosynchronous objects are far away enough to allow them to fall and advance so the resultant is at a rate that is very, very close to the rotation of the earth.
The same orbital theories can give us the Lagrange Points where the gravity effects of two large objects can give regions where a much smaller object suspended in these areas around the larger ones. We do find asteroids in those areas. These points are locations were an answer can actually be obtained analytically for 3 bodied orbital equations. The whole of the solar system, is actually more like constantly trying to remain balanced upon a bicycle. All the different forces seem to balance out on a 4 dimensional field though. These do seem different. Is this your meaning. [Reply]
Imagine those canines going through your femur. And what's that chin all about. WOW!
Millions of years ago, strange-pouched predator stalked South America with fangs bigger than those of the fearsome saber-toothed cat did. It stabbed its prey with its huge, saber-like teeth.
Now, new study reveals a bit more about the predator's dental profile and its hunting strategies, which may reveal a little bit more about saber-toothed animals in general. This ancient carnivore packed most of its power in a robust set of arms, strong neck muscles and knack for precision, researchers say.
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The findings are published in the journal PLOS One.
Known as Thylacosmilus atrox, this animal looked and behaved like nothing alive today. Its closest living relatives are the Australian and American marsupials, but even they fail to show precisely the animal's behavior and skills of hunting.
Thylacosmilus atrox had larger teeth proportionally to its body in comparison with saber-tooth tiger Smilodon fatalis, making it one of the more interesting saber-toothed animals to study.
These animals were separated by at least 125 million years of evolution.
In the new study, scientists constructed and compared sophisticated computer models of both the saber-toothed tiger and Thylacosmilus to learn their behavior and hunting strategies. These models were then "crash-tested" in simulations of biting and killing behavior. This allowed the scientists to determine exactly how these creatures may have subdued their prey.
"We found that both saber-tooth species were similar in possessing weak jaw-muscle-driven bites compared to the leopard, but the mechanical performance of the saber-tooths' skulls showed that they were both well-adapted to resist forces generated by very powerful neck muscles," said Stephen Wroe, leader of the research team, in a news release. "But compared to the placental Smilodon, Thylacosmilus was even more extreme."
Thylacosmilus' bite was less powerful than a domestic cat, yet its skull easily outperformed the saber-tooth tiger in response to strong forces from hypothetical neck muscles, say researchers.
Then, how did they hunt? Thylacosmilus first held its prey to the ground with its powerful arms and then, with great precision, tore down with its relatively delicate teeth. This allowed it to make a quick meal.
Thylacosmilus became extinct 3.5 million years ago, and it had the largest canines of any known saber-toothed beast. Its fangs constantly grew throughout its lifetime and had roots extending even into its skull. The teeth also fit over long sheath-like ridges that extended down from the animal's lower jaw.
"It may not have been the smartest of mammalian super-predators-but in terms of specialization, Thylacosmilustook the already extreme saber-tooth lifestyle to a whole new level," said Wroe in a news release.
Originally Posted by chefsos:
I had someone tell me several years ago, that orbit at low altitude such as the ISS does, isn't technically an orbit at all. It's a controlled fall, with the speed sufficient to keep it continually falling "over the horizon", so to speak. While that didn't blow my mind, I gotta admit it popped a little.
I'm certain you know this stuff, so: was he full of shit?
Hmm...then maybe you should consider the fact that we are in a "controlled" free fall towards the sun! :-) [Reply]
