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Sun sends more 'tsunami waves' to Voyager 1 - 0 views

  • NASA's Voyager 1 spacecraft has experienced a new "tsunami wave" from the sun as it sails through interstellar space
  • Such waves are what led scientists to the conclusion, in the fall of 2013, that Voyager had indeed left our sun's bubble, entering a new frontier
  • "Normally, interstellar space is like a quiet lake,
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  • Ed Stone of the California Institute of Technology
  • But when our sun has a burst, it sends a shock wave outward that reaches Voyager about a year later. The wave causes the plasma surrounding the spacecraft to sing."
  • Data from this newest tsunami wave generated by our sun confirm that Voyager is in interstellar space
  • The mission has not left the solar system—it has yet to reach a final halo of comets surrounding our sun—but it broke through the wind-blown bubble, or heliosphere, encasing our sun
  • ur sun goes through periods of increased activity, where it explosively ejects material from its surface, flinging it outward
  • These events, called coronal mass ejections, generate shock, or pressure, waves. Three such waves have reached Voyager 1 since it entered interstellar space in 2012
  • The first was too small to be noticed when it occurred and was only discovered later, but the second was clearly registered by the spacecraft's cosmic ray instrument in March of 2013
  • another instrument on Voyager
  • The plasma wave instrument can detect oscillations of the plasma electrons
  • This ringing of the plasma bell is what led to the key evidence showing Voyager had entered interstellar space
  • "The tsunami wave rings the plasma like a bell," said Stone. "While the plasma wave instrument lets us measure the frequency of this ringing, the cosmic ray instrument reveals what struck the bell—the shock wave from the sun."
  • denser plasma oscillates faster, the team was able to figure out the density of the plasma
  • In 2013, thanks to the second tsunami wave, the team acquired evidence that Voyager had been flying for more than a year through plasma that was 40 times denser than measured before—a telltale indicator of interstellar space
  • Now, the team has new readings from a third wave from the sun, first registered in March of this year
  • These data show that the density of the plasma is similar to what was measured previously, confirming the spacecraft is in interstellar space
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Lake on Saturn's Largest Moon May Have Waves - Scientific American - 0 views

  • meras on NASA's spacecraft Cassini recently saw what appear to be waves on one of Titan's largest methane lakes
  • a signal scientists have long searched for but never found
  • If confirmed, the discovery would mark the first time waves have been seen outside Earth.
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  • team found patterns in the sunlight reflecting off a northern lake called Punga Mare that they interpret as two-centimeter-high waves
  • There
  • may be a mudflat instead of a deep lake, and a shallow film of liquid on top may be the cause of the unique light signature
  • If life on Titan exists,
  • the best place to look
  • is in large bodies of liquid—the kind that form waves
  • Waves on Titan
  • would confirm that the lakes actually are deep reservoirs of methane and ethane,
  • True liquid bodies would also make a robotic spacecraft mission to explore Titan's habitability more feasible
  • By 2017 scientists should know for certain whether what they are seeing is indeed caused by waves
  • Cassini has been observing the moon during its northern winter, when weak winds are at work
  • As spring
  • over the next few years, bringing stronger winds to kick up seas, the probe should capture more definitive evidence of waves if they exist
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Alan Guth on new insights into the 'Big Bang' - 0 views

  • Q: Can you explain the theory of cosmic inflation that you first put forth in 1980?
  • usually describe inflation as a theory of the "bang" of the Big Bang
  • describes the propulsion mechanism that drove the universe into the period of tremendous expansion that we call the Big Bang
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  • The original Big Bang theory was really a theory of the aftermath of the bang
  • described how the universe was cooled by the expansion, and how the expansion was slowed by the attractive force of gravity
  • Inflation proposes that the expansion of the universe was driven by a repulsive form of gravity.
  • According to Newton, gravity is a purely attractive force, but this changed with Einstein and the discovery of general relativity
  • General relativity describes gravity as a distortion of spacetime, and allows for the possibility of repulsive gravity
  • Modern particle theories strongly suggest that at very high energies, there should exist forms of matter that create repulsive gravity
  • Inflation
  • proposes that at least a very small patch of the early universe was filled with this repulsive-gravity material
  • During the period of exponential expansion, any ordinary material would thin out, with the density diminishing to almost nothing
  • The repulsive-gravity material actually maintains a constant density as it expands, no matter how much it expands
  • While this appears to be a
  • violation
  • of the conservation of energy, it is actually
  • consistent
  • a peculiar feature of gravity: The energy of a gravitational field is negative
  • As the patch expands at constant density, more and more energy, in the form of matter, is created
  • But at the same time, more and more negative energy appears in the form of the gravitational field that is filling the region
  • The total energy remains constant, as it must, and therefore remains very small.
  • It is possible that the total energy of the entire universe is exactly zero, with the positive energy of matter completely canceled by the negative energy of gravity
  • At some point the inflation ends because the repulsive-gravity material becomes metastable
  • decays into ordinary particles, producing a very hot soup of particles that form the starting point of the conventional Big Bang
  • point the repulsive gravity turns off, but the region continues to expand in a coasting pattern for billions of years to come
  • inflation is a prequel to the era that cosmologists call the Big Bang, although it of course occurred after the origin of the universe, which is often also called the Big Bang.
  • Q: What is the new result announced this week, and how does it provide critical support for your theory?
  • The early universe, as we can see from the afterglow of the cosmic microwave background (CMB) radiation, was incredibly uniform,
  • to have structure form at all, there needed to be small nonuniformities at the end of inflation
  • The tiny nonuniformities that did exist were then amplified by gravity
  • these nonuniformities—which later produce stars, galaxies, and all the structure of the universe—are attributed to quantum theory
  • The temperature nonuniformities in the cosmic microwave background were first measured in 1992 by the COBE satellite
  • have not generally been seen as proof of inflation, in part because it is not clear that inflation is the only possible way that these fluctuations could have been produced.
  • The stretching effect of inflation,
  • also acts on the geometry of space itself, which according to general relativity is flexible
  • Space can be compressed, stretched, or even twisted.
  • The geometry of space also fluctuates on small scales, due to the physics of quantum theory, and inflation also stretches these fluctuations, producing gravity waves in the early universe.
  • The new result,
  • is a measurement of these gravity waves, at a very high level of confidence.
  • They do not see the gravity waves directly, but instead they have constructed a very detailed map of the polarization of the CMB in a patch of the sky.
  • They have observed a swirling pattern in the polarization (called "B modes") that can be created
  • by gravity waves in the early universe
  • This is the first time that even a hint of these primordial gravity waves has been detected
  • it is also the first time that any quantum properties of gravity have been directly observed.
  • Q: How would you describe the significance of these new findings, and your reaction to them?
  • The significance of these new findings
  • help tremendously in confirming the picture of inflation.
  • As far as we know, there is nothing other than inflation that can produce these gravity waves
  • it tells us a lot about the details of inflation that we did not already know
  • it determines the energy density of the universe at the time of inflation, which is something that previously had a wide range of possibilities.
  • By determining the energy density of the universe at the time of inflation, the new result also tells us a lot about which detailed versions of inflation are still viable, and which are no longer viable
  • The current result is not by itself conclusive, but it points in the direction of the very simplest inflationary models that can be constructed.
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First hints of gravitational waves in the Big Bang's afterglow - 0 views

  • As the last untested prediction of Einstein's Theory of General Relativity, finding gravitational waves is a big deal.
  • Scientists at the Harvard-Smithsonian Centre for Astrophysics in the US have announced
  • what they believe is the indirect detection of gravitational waves in the afterglow of the Big Bang.
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  • The BICEP discovery provides further indirect evidence for the existence of gravitational waves
  • the 1993 Nobel Prize in Physics was awarded to Russell Hulse and Joseph Taylor for finding a double pulsar that strongly supported these "ripples" in spacetime
  • Before this announcement
  • we could measure the universe back to about a minute after the Big Bang.
  • The finding
  • has allowed us to study the universe when it was a trillionth of a trillionth of a trillionth of a second old
  • tiny changes in temperature that were discovered by the COBE satellite (winning the 2006 Nobel Prize)
  • Alternative theories to inflation do not produce gravitational waves so
  • is strong evidence not only of the gravitational wave background but also inflation itself.
  • there has still been no direct detection of the gravitational radiation.
  • The first direct detection should follow in a few months
  • It is envisaged that the experiment will directly detect gravitational radiation coming from astrophysical sources from nearby galaxies
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Magma Boils Beneath Antarctic Ice | Science/AAAS | News - 0 views

  • Marie Byrd Land is a desolate region of Antarctica buried deep beneath the West Antarctic Ice Sheet
  • Historic eruptions have punctured the ice sheet, creating a chain of volcanoes amid the ice
  • researchers have shown that molten rock still stirs deep underground
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  • Only the largest eruptions could melt all the ice above them and poke through to the surface, but even smaller eruptions could potentially cause global sea level to rise, although no one knows how big the rise might be
  • The crust is thinned by the West Antarctic Rift System, a series of giant rift valleys beneath the ice sheet
  • erupted lava from underground magma chambers has burst through the ice repeatedly over geological history as the plates moved over the top
  • No one knew whether magma was still stirring
  • until seismic monitoring stations were installed on the ice between 2007 and 2010.
  • Researchers built the stations to study the shifting crustal blocks of the West Antarctic Rift System
  • But seismologist
  • found another use
  • They noticed a series of small earthquakes, mainly occurring during two “seismic swarms” in January and February 2010 and March 2011
  • These earthquakes were unusual: The ground was shaking much more slowly during the quakes than one would expect from the plates grinding against each other
  • looked at two different types of waves that come in—the P wave, which is the primary wave, and the S wave, which is the secondary wave
  • calculations revealed that the waves had come from 25 to 40 kilometers below Earth's surface and were centered around a point
  • approximately the point the volcanic activity should have reached if it had continued the linear trend of volcanoes to the south
  • The exact cause of these deep quakes is not understood, but they are thought to result from the movement of magma deep below active or soon-to-be active volcanoes
  • They found that the area showed a slightly higher magnetic field than the surrounding area and that there was a bump in the crust—common signals of magmatic activity
  • Radar mapping also indicated a layer of volcanic ash embedded in the ice
  • probably
  • from an eruption of Mount Waesche about 8000 years ago—very recent geological history
  • There is no evidence of an actual eruption since then, but, because magma is still moving deep under the Earth, an eruption could occur at any time
  • The current center of volcanic activity is covered by at least 1 kilometer of ice, and it would take an exceptionally large eruption to melt all this
  • But an eruption could make its presence felt in subtler ways. As fresh snow adds to their own mass, ice sheets flow downward into the sea
  • melting the base of the ice sheet, an eruption could speed up this flow, potentially raising the level of the ocean. No one knows how significant such a rise might be
  • Any effect on the ice sheet above, and thus any effect on the oceans, would probably be quite small
  • a proper study is needed to find out how significant volcanic activity could be to future sea levels
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Effects of Einstein's Elusive Gravity Waves Observed - 0 views

  • According to Einstein, space-time is a structure in itself
  • also predicted that exceptionally massive, rapidly rotating objects — such as a white dwarf binary pair — would create outwardly-expanding ripples in space-time that would ultimately “steal” kinetic energy from the objects themselves. These gravitational waves would be very subtle, yet in theory, observable.
  • Originally observed in 2011 eclipsing each other
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  • once every six minutes, the stars now eclipse six seconds sooner
  • equates to a predicted orbital period reduction of about 0.25 milliseconds each year
  • Although this isn’t “direct” observation of gravitational waves, it is evidence inferred by their predicted effects… akin to watching a floating lantern in a dark pond at night moving up and down and deducing that there are waves present
  • Based on these measurements, by April 2013 the stars will be eclipsing each other 20 seconds sooner than first observed.
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Smallest Exoplanet Yet Discovered by 'Listening' to a Sun-like Star - 0 views

  • Scientists have discovered a new planet orbiting a Sun-like star, and the exoplanet is the smallest yet found in data from the Kepler mission
  • Kepler-37b, is smaller than Mercury, but slightly larger than Earth’s Moon
  • discovery came from a collaboration between Kepler scientists and a consortium of international researchers who employ asteroseismology
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  • measuring oscillations in the star’s brightness caused by continuous star-quakes, and turning those tiny variations in the star’s light into sounds
  • The bigger the star, the lower the frequency, or ‘pitch’ of its song
  • The measurements made by the astroseismologists allowed the Kepler research team to more accurately measure the tiny Kepler-37b
  • revealing two other planets in the same planetary system: one slightly smaller than Earth and one twice as large
  • Kepler-37b is very likely a rocky planet with no atmosphere or water, similar to Mercury
  • “The detection of such a small planet shows for the first time that stellar systems host planets much smaller as well as much larger than anything we see in our own Solar System.”
  • host star, Kepler-37, is about 210 light-years from Earth
  • All three planets orbit the star at less than the distance Mercury is to the Sun
  • Kepler-37b orbits every 13 days at less than one-third Mercury’s distance from the Sun
  • estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin
  • hot enough to melt the zinc in a penny
  • Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively
  • The size of the star must be known in order to measure the planet’s size accurately
  • scientists examined sound waves generated by the boiling motion beneath the surface of the star
  • The technique for stellar seismology is analogous to how geologists use seismic waves generated by earthquakes to probe the interior structure of Earth
  • sound waves travel into the star and bring information back up to the surface
  • waves cause oscillations that Kepler observes as a rapid flickering of the star’s brightness
  • barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure
  • why most objects previously subjected to asteroseismic analysis are larger than the Sun
  • Kepler-37 has a radius just three-quarters of the Sun
  • the radius of the star is known to 3 percent accuracy, which translates to exceptional accuracy in the planet’s size.
  • this discovery took a long time to verify, as the signature of this very small exoplanet was hard to confirm
  • Kepler is sending astronomers photometry data that’s “probably the best we’ll see in our lifetimes
  • uncovered a planet smaller than any in our solar system orbiting one of the few stars that is both bright and quiet, where signal detection was possible
Chris Fisher

Trillion FPS Camera Captures Advancing Light Waves - 0 views

  • MIT’s new camera will shoot one trillion frames per second.
  • One trillion seconds is over 31,688 years
  • played it back at 30fps, it’d still take you over 1,000 years to watch it.
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  • use “femtosecond laser illumination, picosecond-accurate detectors and mathematical reconstruction techniques” to illuminate a scene and then capture the pulses of laser light.
  • The movies are 480 frames long, and show a slice in time of just 1.71 picoseconds.
  • The result is a movie of an advancing wave of light.
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A Close-up Look at the Massive Solar Storm that Shook the Sun - 0 views

  • large X5.4 solar flare that erupted on the Sun on March 7, 2012 at 00:28 UT, (7:28 PM EST on March 6).
  • high-definition views from the Solar Dynamics Observatory also show the subsequent solar tsunami that rippled across the Sun, appearing as though the Sun ‘shook’ from the force of the flare.
  • NASA Goddard’s Space Weather Lab and NOAA Space Weather Prediction Center say surely there will be aurorae from this blast
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  • After the first big blast, about an hour later, at 01:14 UT (8:14 PM EST, March 6) the same region let loose an X1.3 class flare. An X1 is 5 times smaller than an X5 flare
  • the region had already produced numerous M-class and one X-class flare,
  • region continues to rotate across the front of the sun, so these latest flares were more Earth-facing than the previous ones
  • big blast did trigger a temporary radio blackout on the sunlit side of Earth that interfered with radio navigation and short wave radio.
  • that solar tsunami
  • waves move at over a million miles per hour
  • one side of the Sun to the other in about an hour
  • movie shows two distinct waves. The first seems to spread in all directions; the second is narrower, moving toward the southeast
  • waves are associated with, and perhaps trigger, fast coronal mass ejections, so it is likely that each one is connected to one of the two CMEs that were associated with the flares
  • Close-up Look at the Massive Solar Storm
Chris Fisher

U.S. Government Glossed Over Cancer Concerns As It Rolled Out Airport X-Ray Scanners - ... - 1 views

  • Research suggests that anywhere from six to 100 U.S. airline passengers each year could get cancer from the machines.
  • Because of a regulatory Catch-22, the airport X-ray scanners have escaped the oversight required for X-ray machines used in doctors’ offices and hospitals. The reason is that the scanners do not have a medical purpose, so the FDA cannot subject them to the rigorous evaluation it applies to medical devices.
  • FDA has limited authority to oversee some non-medical products and can set mandatory safety regulations. But the agency let the scanners fall under voluntary standards set by a nonprofit group heavily influenced by industry.
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  • As for the TSA, it skipped a public comment period required before deploying the scanners. Then, in defending them, it relied on a small body of unpublished research to insist the machines were safe, and ignored contrary opinions from U.S. and European authorities that recommended precautions, especially for pregnant women.
  • Both the FDA and TSA say due diligence has been done to assure the scanners’ safety.
  • ProVision, made by defense contractor L-3 Communications, a passenger enters a chamber that looks like a round phone booth and is scanned with millimeter waves, a form of low-energy radio waves, which have not been shown to strip electrons from atoms or cause cancer.
  • In July, the European Parliament passed a resolution that security “scanners using ionizing radiation should be prohibited” because of health risks.
  • Some scientists argue the danger is exaggerated. They claim low levels stimulate the repair mechanism in cells, meaning that a little radiation might actually be good for the body.
  • But in the authoritative report on low doses of ionizing radiation, published in 2006, the National Academy of Sciences reviewed the research and concluded that the preponderance of research supported the linear link. It found “no compelling evidence” that there is any level of radiation at which the risk of cancer is zero.
  • Rebecca Smith-Bindman, a radiologist at the University of California, San Francisco, estimated that the backscatters would lead to only six cancers over the course of a lifetime among the approximately 100 million people who fly every year. David Brenner, director of Columbia University’s Center for Radiological Research, reached a higher number — potentially 100 additional cancers every year.
  • The government used to have 500 people examining the safety of electronic products emitting radiation. It now has about 20 people.
  • But in 1982, the FDA merged the radiological health bureau into its medical-device unit. “I was concerned that if they were to combine the two centers into one, it would probably mean the ending of the radiation program because the demands for medical-device regulation were becoming increasingly great,” said Villforth, who was put in charge of the new Center for Devices and Radiological Health. “As I sort of guessed, the radiation program took a big hit.”
  • the same 100 million people would develop 40 million cancers over the course of their lifetimes. In this sea of cancer cases, it would be impossible to identify the patients whose cancer is linked to the backscatter machines.
  • the FDA has not set a mandatory safety standard for an electronic product since 1985.
  • As a result, there is an FDA safety regulation for X-rays scanning baggage — but none for X-rays scanning people at airports.
  • The U.S. Customs Service deployed backscatter machines for several years but in limited fashion and with strict supervision. Travelers suspected of carrying contraband had to sign a consent form, and Customs policy prohibited the scanning of pregnant women.
  • In July, a federal appeals court ruled that the agency failed to follow rule-making procedures and solicit public comment before installing body scanners at airports across the country
  • Federal Aviation Administration’s medical institute has advised pregnant pilots and flight attendants that the machine, coupled with their time in the air, could put them over their occupational limit for radiation exposure
  • It was made up of 15 people, including six representatives of manufacturers of X-ray body scanners and five from U.S. Customs and the California prison system. There were few government regulators and no independent scientists.
  • The FDA delegated the task of establishing the voluntary standards to the American National Standards Institute.
  • “Establishing a mandatory standard takes an enormous amount of resources and could take a decade to publish,” said Dan Kassiday, a longtime radiation safety engineer at the FDA.
  • and before 9/11, many states also had the authority to randomly inspect machines in airports. But that ended when the TSA took over security checkpoints from the airlines.
  • Last year, in reaction to public anger from members of Congress, passengers and advocates, the TSA contracted with the Army Public Health Command to do independent radiation surveys. But email messages obtained in a lawsuit brought by the Electronic Privacy Information Center, a civil liberties group, raise questions about the independence of the Army surveys.
  • One email sent by TSA health and safety director Jill Segraves shows that local TSA officials were given advance notice and allowed to “pick and choose” which systems the Army could check.
  • The TSA considered the scanners again after two Chechen women blew up Russian airliners in
  • 2004.
  • Facing a continued outcry over privacy, the TSA instead moved forward with a machine known as a “puffer” because it released several bursts of air on the passengers’ clothes and analyzed the dislodged particles for explosives. But after discovering the machines were ineffective in the field and difficult to maintain, the TSA canceled the program in 2006.
  • Around that time, Rapiscan began to beef up its lobbying on Capitol Hill. It opened a Washington, D.C., office and, according to required disclosures, more than tripled its lobbying expenditures in two years, from less than $130,000 in 2006 to nearly $420,000 in 2008. It hired former legislative aides to Rep. David Price, D-N.C., then chairman of the homeland security appropriations subcommittee, and to Sen. Trent Lott, R-Miss.
  • It started a political action committee and began contributing heavily to Price; Rep. Bennie Thompson, D-Miss., then head of the homeland security committee; Rep. Jane Harman, D-Calif., also on that committee; and Sen. Thad Cochran, R-Miss., the top Republican on the Senate appropriations committee.
  • In addition, it opened a new North Carolina plant in Price’s district and expanded its operations in Ocean Springs, Miss., and at its headquarters in Torrance, Calif., in Harman’s district.
  • “Less than a month after U.S. Senator Trent Lott and other local leaders helped officially open Rapiscan Systems’ new Ocean Springs factory,” Lott’s office announced in a news release in late 2006, “the company has won a $9.1 million Department of Defense contract.”
  • in 2007, with new privacy filters in place, the TSA began a trial of millimeter-wave and backscatter machines at several major airports, after which the agency opted to go with the millimeter-wave machines. The agency said health concerns weren’t a factor.
  • But with the 2009 federal stimulus package, which provided $300 million for checkpoint security machines, the TSA began deploying backscatters as well. Rapiscan won a $173 million, multiyear contract for the backscatters, with an initial $25 million order for 150 systems to be made in Mississippi.        
  •  
    I'm not really sure this is a SciByte story. But it was a good example of a story, with lots of great bits to capture.
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Wireless signals could transform brain trauma diagnostics - 0 views

  • New technology
  • is using wireless signals to provide real-time, non-invasive diagnoses of brain swelling or bleeding.
  • The device analyzes data from low energy, electromagnetic waves, similar to the kind used to transmit radio and mobile signals
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  • The technology
  • could potentially become a cost-effective tool for medical diagnostics and to triage injuries in areas where access to medical care, especially medical imaging, is limited
  • The researchers tested a prototype in a small-scale pilot study of healthy adults and brain trauma patients admitted to a military hospital for the Mexican Army
  • The results from the healthy patients were clearly distinguishable from those with brain damage, and data for bleeding was distinct from those for swelling
  • symptoms of serious head injuries and brain damage are not always immediately obvious, and for treatment, time is of the essence.
  • The researchers took advantage of the characteristic changes in tissue composition and structure in brain injuries
  • For brain edemas, swelling results from an increase in fluid in the tissue
  • For brain hematomas, internal bleeding causes the buildup of blood in certain regions of the brain.
  • Because fluid conducts electricity differently than brain tissue, it is possible to measure changes in electromagnetic properties.
  • Computer algorithms interpret the changes to determine the likelihood of injury.
  • The study involved 46 healthy adults, ages 18 to 48, and eight patients with brain damage, ages 27 to 70.
  • engineers fashioned two coils into a helmet-like device, fitted over the heads of the study participants
  • One coil acts as a radio emitter and the other serves as the receiver. Electromagnetic signals are broadcast through the brain from the emitter to the receiver
  • the waves are extremely weak, and are comparable to standing in a room with the radio or television turned on
  • The device's diagnoses for the brain trauma patients in the study matched the results obtained from conventional computerized tomography (CT) scans
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Treatment with fungi makes a modern violin sound like a Stradiavarius - 0 views

  • Low density, high speed of sound and a high modulus of elasticity – these qualities are essential for ideal violin tone wood.
  • In the late 17th and early 18th century the famous violin maker Antonio Stradivari used a special wood that had grown in the cold period between 1645 and 1715
  • long winters and the cool summers, the wood grew especially slowly and evenly, creating low density and a high modulus of elasticity
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  • A good violin depends not only on the expertise of the violin maker, but also on the quality of the wood that is used.
  • Swiss wood researcher
  • has succeeded in modifying the wood for a violin through treatment with special fungi
  • making it sound indistinguishably similar to a Stradivarius
  • discovered two species of fungi
  • which decay Norway spruce and sycamore – the two important kinds of wood used for violin making – to such an extent that their tonal quality is improved
  • Normally fungi reduce the density of the wood, but at the same time they unfortunately reduce the speed with which the sound waves travel through the wood
  • unique feature of these fungi is that they gradually degrade the cell walls, thus inducing a thinning of the walls
  • , a stiff scaffold structure remains via which the sound waves can still travel directly
  • the wood remains just as resistant to strain as before the fungal treatment
  • Before the wood is further processed to a violin, it is treated with ethylene oxide gas. "No fungus can survive that
  • mycowood (wood treated with wood decay fungi
  • on September 7, 2012 in
  • reported on his research and gave a preview of what his wood treatment method could mean, particularly for young violinists
  • In 2009 the violins were played in a blind, behind-the-curtain test versus a genuine Stradivarius from 1711
  • Both the jury of experts and the majority of the audience thought that the mycowood violin that Schwarze had treated with fungi for nine months was the actual Strad
  • Currently Professor Schwarze is working on an interdisciplinary project to develop a quality-controlled treatment for violin wood, with successful, reliable and reproducible results
  • cessful implementation of biotechnological methods for treating soundboard wood could in the future give young musicians the opportunity to play on a violin with the sound quality of an expensive – and for most musicians unaffordable – Stradivarius
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May 4 - Today in Science History - Scientists born on May 4th, died, and events - 0 views

  • Galactic radio waves
  • In 1933, the discovery of radio waves from the centre of the Milky Way galaxy was by described by Karl Jansky in a paper he read to the International Radio Union in Washington. The galactic radio waves were very low intensity, short wavelength (14.6 m, frequency about 20 MHz) and required sensitive apparatus for their detection. Their intensity varied regularly with the time of day, and with the seasons. They came from an unchanging direction in space, independent of terrestrial sources. He had conducted his research on static hiss at the radio research department of Bell Telephone Labs, Holmdel, N.J. The New York Times carried a front page report the next day
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NASA beams Mona Lisa to Lunar Reconnaissance Orbiter at the moon (w/ video) - 0 views

  • To clean up transmission errors introduced by Earth's atmosphere (left), Goddard scientists applied Reed-Solomon error correction (right), which is commonly used in CDs and DVDs.
  • Typical errors include missing pixels (white) and false signals (black). The white stripe indicates a brief period when transmission was paused
  • As part of the first demonstration of laser communication with a satellite at the moon, scientists with NASA's Lunar Reconnaissance Orbiter (LRO) beamed an image of the Mona Lisa to the spacecraft from Earth.
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  • he iconic image traveled nearly 240,000 miles in digital form from the Next Generation Satellite Laser Ranging (NGSLR) station at NASA's Goddard Space Flight Center in Greenbelt, Md., to the Lunar Orbiter Laser Altimeter (LOLA) instrument on the spacecraft.
  • By transmitting the image piggyback on laser pulses that are routinely sent to track LOLA's position, the team achieved simultaneous laser communication and tracking.
  • This is the first time anyone has achieved one-way laser communication at planetary distances
  • "In the near future, this type of simple laser communication might serve as a backup for the radio communication that satellites use
  • In the more distant future, it may allow communication at higher data rates than present radio links can provide
  • Typically, satellites that go beyond Earth orbit use radio waves for tracking and communication
  • LRO is the only satellite in orbit around a body other than Earth to be tracked by laser as well.
  • Precise timing was the key to transmitting the image
  • divided the Mona Lisa image into an array of 152 pixels by 200 pixels
  • Every pixel was converted into a shade of gray, represented by a number between zero and 4,095.
  • Each pixel was transmitted by a laser pulse, with the pulse being fired in one of 4,096 possible time slots during a brief time window allotted for laser tracking
  • he complete image was transmitted at a data rate of about 300 bits per second.
  • The laser pulses were received by LRO's LOLA instrument, which reconstructed the image based on the arrival times of the laser pulses from Earth
  • This was accomplished without interfering with LOLA's primary task of mapping the moon's elevation and terrain and NGSLR's primary task of tracking LRO.
  • The success of the laser transmission was verified by returning the image to Earth using the spacecraft's radio telemetry system.
  • Turbulence in Earth's atmosphere introduced transmission errors even when the sky was clear.
  • To overcome these effects,
  • employed Reed-Solomon coding, which is the same type of error-correction code commonly used in CDs and DVDs.
  • The next step after LLCD is the Laser Communications Relay Demonstration (LCRD), NASA's first long-duration optical communications mission.
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Wilkinson Microwave Anisotropy Probe - Wikipedia, the free encyclopedia - 0 views

  • a spacecraft which measures differences in the temperature of the Big Bang's remnant radiant heat – the Cosmic Microwave Background Radiation – across the full sky
  • The WMAP spacecraft was launched on June 30, 2001,
  • The WMAP mission succeeds the COBE space mission and was the second medium-class (MIDEX) spacecraft of the Explorer program.
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  • WMAP's measurements played the key role in establishing the current Standard Model of Cosmology
  • WMAP data are very well fit by a universe that is dominated by dark energy in the form of a cosmological constant
  • The anisotropies then are used to measure the universe's geometry, content, and evolution; and to test the Big Bang model, and the cosmic inflation theory
  • he map contains 3,145,728 pixels, and uses the HEALPix scheme to pixelize the sphere
  • The telescope's primary reflecting mirrors are a pair
  • that focus the signal onto a pair of
  • secondary reflecting mirrors.
  • shaped for optimal performance: a carbon fibre shell upon a Korex core, thinly-coated with aluminium and silicon oxide.
  • The secondary reflectors transmit the signals to the corrugated feedhorns that sit on a focal plane array box beneath the primary reflectors
  • The receivers are polarization-sensitive differential radiometers measuring the difference between two telescope beams.
  • To avoid collecting Milky Way galaxy foreground signals, the WMAP uses five discrete radio frequency bands
  • The WMAP's trajectory and orbit
  • The WMAP observes in five frequencies, permitting the measurement and subtraction of foreground contamination (from the Milky Way
  • Foreground contamination is removed in several ways
  • First, subtract extant emission maps from the WMAP's measurements; second, use the components' known, spectral values to identify them; third, simultaneously fit the position and spectra data of the foreground emission, using extra data sets
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MESSENGER Solves Solar Flare Mystery - 0 views

  • the MESSENGER spacecraft was able to capture a average-sized solar flare
  • allowing astronomers to study high-energy solar neutrons at less than 1 astronomical unit (AU) from the sun for the first time
  • Previously, only the neutron bursts from the most powerful solar flares have been recorded on neutron spectrometers on Earth or in near-Earth orbit
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  • results help solve a mystery of why some coronal mass ejections produce almost no energetic protons that reach the Earth, while others produce huge amounts
  • inferred the continuous production of protons in the 30-to-100-MeV (million electron volt) range due to the flare
  • MESSENGER’s Neutron Spectrometer was able to record neutrons from this flare over a period of six to ten hours
  • at least some moderate-sized flares continuously produce high-energy neutrons in the solar corona
  • Solar flares spew high-energy neutrons into interplanetary space. Typically, these bursts last about 50 to 60 seconds at the sun.
  • About 90 percent of all ions produced by a solar flare remain locked to the sun on closed magnetic lines
  • another population results from the decay of the neutrons near the sun
  • forms an extended seed population in interplanetary space that can be further accelerated by the massive shock waves produced by the flares
  • It appears that these seed populations of energetic protons near the sun could provide the answer
  • Sometimes they’re in the right place for the shock waves to send them toward Earth
  • seed populations are not evenly distributed
  • at other times they’re in locations where the protons are accelerated in directions that don’t take them near Earth
  • Energetic protons from solar flares can damage Earth-orbiting satellites and endanger astronauts on the International Space Station or on missions to the Moon and Mars.
  • scientists need to know a lot more about the mechanisms that produce flares and which flare events are likely to be dangerous
  • At some point they hope to be able to predict space weather — where precipitation is in the form of radiation — with the same accuracy that forecasters predict rain or snow on Earth.
  • The beauty of MESSENGER is that it’s going to be active from the minimum to the maximum solar activity during Solar Cycle 24
  • observe the rise of a solar cycle much closer to the sun than ever before
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Ultrathin flexible brain implant offers unique look at seizures - 0 views

  • Researchers funded by the National Institutes of Health have developed a flexible brain implant that could one day be used to treat epileptic seizures
  • a type of electrode array that conforms to the brain's surface – to take an unprecedented look at the brain activity underlying seizures
  • Someday, these flexible arrays could be used to pinpoint where seizures start in the brain and perhaps to shut them down
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  • These flexible electrode arrays could significantly expand surgical options for patients with drug-resistant epilepsy
  • In an animal model, the researchers saw spiral waves of brain activity not previously observed during a seizure
  • Similar waves are known to ripple through cardiac muscle during a type of life-threatening heart rhythm called ventricular fibrillation.
  • A stimulating electrode array might one day be designed to suppress seizure activity, working like a pacemaker for the brain
  • The brain contains billions of interconnected neurons that normally transmit electrical pulses
  • During a seizure, these pulses occur in abnormal, synchronized, rapid-fire bursts that can cause convulsions, loss of consciousness and other symptoms
  • is made of a pliable material that is only about one quarter the thickness of a human hair
  • It contains 720 silicon nanomembrane transistors in a multiplexed 360-channel array, which allow for minimal wiring and dense packing of the electrodes
  • The flexibility of the array allows it to conform to the brain's complex shape, even reaching into grooves that are inaccessible to conventional arrays
  • the array could be rolled into a tube and delivered into the brain through a small hole rather than by opening the skull
  • The researchers tested the flexible array on cats. Although mice and rats are used for most neuroscience research, cats have larger brains that are anatomically more like the human brain, with simplified folds and grooves
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January 26 - Today in Science History - Scientists born on January 26th, died, and events - 0 views

  • Canadian earthquake   In 1700, an earthquake, the most intense Canada has ever seen, hit the sea floor off the British Columbia coast. Long before Europeans first landed on Vancouver Island, native legend tells of a great disaster. The sea rose in a heaving wave, and landslides buried a sleeping village. Myth was resolved with science in 2003 by government research. Earthquakes of that intensity cause tidal waves, and Japanese written history tells of a massive tsunami striking fishing villages the next day along the coast of Honshu, killing hundreds. Coupled with geological evidence of the level 9 quake, the connection was clear. Mythology and seismology came together to validate history.
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