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Mars Base

Alan Guth on new insights into the 'Big Bang' - 0 views

phys.org/...03-alan-guth-insights-big.html

scibyte124 Inflation

shared by Mars Base on 22 Mar 14 - No Cached
  • 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
  • ...49 more annotations...
  • 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.
Mars Base

Speed-bump device converts traffic energy to electricity - 0 views

www.physorg.com/...raffic-energy-electricity.html

scibyte21 traffic electricity

shared by Mars Base on 10 Nov 11 - No Cached
  • A Maryland company
  • has devised that kind of speed-bump device
  • has devised that kind of speed-bump device
  • ...17 more annotations...
  • A Maryland company
  • that harvests kinetic energy from vehicles and converts the energy into electricity
  • for installation where vehicles are traveling faster than 15 mph and are slowing-down before stopping, including parking lots, border crossings, exit ramps, neighborhoods with traffic calming zones, rest areas, toll booths, and travel plazas
  • devices become a part of the toll booths, rest areas, parking lots, airport arrival and departure areas, city lighting systems, zones in other places where traffic should be slowing down—scenarios that can benefit from a greener approach to energy and electricity cost savings.
  • devices become a part of the toll booths, rest areas, parking lots, airport arrival and departure areas, city lighting systems, zones in other places where traffic should be slowing down—scenarios that can benefit from a greener approach to energy and electricity cost savings
  • recently got a boost in publicity by partnering with the city of Roanoke in Virginia to put its MotionPower Express system to the test
  • recently got a boost in publicity by partnering with the city of Roanoke in Virginia to put its MotionPower Express system to the test
  • that harvests kinetic energy from vehicles and converts the energy into electricity
  • for installation where vehicles are traveling faster than 15 mph and are slowing-down before stopping, including parking lots, border crossings, exit ramps, neighborhoods with traffic calming zones, rest areas, toll booths, and travel plazas.
  • during a busy time when the center was hosting a gun show and circus. A total of 580 cars passed over the rumble strip in six hours.
  • was during a busy time when the center was hosting a gun show and circus. A total of 580 cars passed over the rumble strip in six hours.
  • Reports claim this traffic over this amount of time generated enough electricity to power an average U.S. home for a day
  • Reports claim this traffic over this amount of time generated enough electricity to power an average U.S. home for a day.
  • traffic over a six hour period was claimed to produce enough electricity for a 150 square-foot electronic billboard or marquee for a day.
  • traffic over a six hour period was claimed to produce enough electricity for a 150 square-foot electronic billboard or marquee for a day
  • estimated that each MotionPower speed bump would cost $1,500 to $2,000 and earn back its cost in two to three years
  • estimated that each MotionPower speed bump would cost $1,500 to $2,000 and earn back its cost in two to three years.
Mars Base

Polymer Power Drives Tiny Reactions - Science News - 0 views

www.sciencenews.org/...er_power_drives_tiny_reactions

scibyte38

shared by Mars Base on 14 Mar 12 - No Cached
  • Applying force to polymers in water generates enough energy to drive chemical reactions
  • won’t replace large-scale energy operations
  • offers a way to harness the wisps of unused energy generated by everyday endeavors, like walking or compacting plastic bags at a recycling center
  • ...13 more annotations...
  • capturing such energy could lead to cheap, clean ways to sanitize a small container of water, for example, or to run a simple lab bench reaction
  • Scientists knew that bonds can break when mechanical force is applied to a polymer
  • breakage can generate free radicals, atoms with unpaired electrons that are eager to engage in further reactions
  • new work shows that when a polymer is squeezed in water, the free radicals migrate and react with the water, generating enough hydrogen peroxide to spur other reactions.
  • When the scientists added gold and silver metal salts to a PDMS tube filled with water, squeezing the tube powered reactions that generated gold and silver nanoparticles
  • also injected the sole of a Nike LeBron sneaker with water and a compound that fluoresces when it is cleaved
  • Half an hour of walking applied force to the polymers in the sneaker’s sole, and the resulting free radicals made enough hydrogen peroxide to cleave the fluorescing compound and make the sole glow. 
  • capturing and converting the mechanical energy of polymer squeezing into energy for driving reactions can be as efficient as 30 percent
  • comparable to some power plants that use coal.
  • PDMS is used in some medical devices such as catheters, and in some breast implants, raising the issue that normal wear in the body might generate free radicals that could cause inflammation and other problems
  • adding an antioxidant such as vitamin E, which latches onto free radicals, to the implant ingredients might be a quick and easy way to
  • Some of the body’s immune cells, though, generate well more hydrogen peroxide than that generated by the polymers
  • the fact that enough free radicals are generated to drive reactions — which might even contribute to the breakdown of medical devices — is interesting, Tang says. “I don’t know how unique it is or material-specific, but it could have potential importance.”
Mars Base

'Cool pavement' technologies studied to address hot urban surfaces - 0 views

phys.org/...nt-technologies-hot-urban.html

scibyte63 pavement

shared by Mars Base on 14 Sep 12 - No Cached
  • n a typical city, pavements account for 35 to 50 percent of surface area,
  • half is comprised of streets and about 40 percent of exposed parking lots
  • Most of these
  • ...36 more annotations...
  • are constructed with dark materials
  • "Because dark pavements absorb almost all of the sun's energy, the pavement surface heats up, which in turn also warms the local air
  • Berkeley Lab scientists have been studying "cool pavement" technologies
  • Like cool roofs, which are lighter-colored roofs that keep the air both inside and outside the building cooler by reflecting more of the sun's energy
  • pavements reflect as much as 30 to 50 percent of the sun's energy, compared to only 5 percent for new asphalt (and 10 to 20 percent for aged asphalt)
  • Heat Island Group has converted a portion of a new temporary parking lot at Berkeley Lab into a cool pavement exhibit that will also allow them to evaluate the products over time
  • provides an opportunity to feature cool pavement coatings that are applied directly to existing paved surfaces
  • the exhibit features six coatings donated by two manufacturers
  • Emerald Cities Cool Pavement and StreetBond.
  • Cool pavements can either be made from traditional pavement materials that are lighter in color
  • such as cement concrete
  • or can consist of cool-colored coatings or surface treatments for asphalt surfaces
  • An ideal design goal would be a pavement with solar reflectance of at least 35 percent
  • Sealcoats are a common maintenance practice for parking lots and schoolyards since the asphalt pavement structure degrades over tim
  • asphalt
  • can be used in lieu of a sealcoat, and are a good strategy for cities looking to introduce cool pavement technologies
  • Cool pavements come in different hues, including green, blue and yellow, and their solar reflectance value depends on both color and material
  • some colors that look dark but are actually more reflective in the near infrared spectrum
  • scientists will be collecting data to see how the coatings fare over time
  • At some point they will reach an equilibrium at which the solar reflectance won't degrade much anymore
  • very interested to see what happens when it rains, which may help the coatings self-clean and restore higher reflectance
  • "Across an entire city, small changes in air temperature could be a huge benefit as it can slow the formation of smog
  • Just a couple of degrees can also reduce peak power demand, by reducing the energy load from air-conditioning
  • Chicago has reported energy savings from using solar-reflective pavements in its alleys
  • more reflective parking lots could allow building owners and cities to save on energy needed to illuminate streets and parking lots
  • field studies are needed to verify and quantify the results.
  • many of these benefits have been confirmed by scientific models
  • leading a study
  • will closely monitor the solar reflectance values and temperatures of 20 x 24 square-foot pavement sections of six different materials on a residential street on the UC Davis campu
  • scientists hope to better understand how changes in solar reflectance over time affect heat transfer throughout the pavement structure
  • may assist policymakers and pavement professionals in making informed decisions regarding cool pavement requirements for building codes and project specifications
  • may also help sell cool pavement coatings since they tend to be more expensive than traditional sealants
  • hurdle is that the benefits of cool pavements are more for the public rather than the building owner
  • benefits are less immediately tangible than for cool roofs
  • initial cost premium can potentially be offset over the lifespan of the product with increased durability and less need for ongoing maintenance
  • schoolyards are a particular target because of the negative health implications of hot blacktops for schoolchildren
Mars Base

Scientists report hint of dark matter in first results from $2 billion cosmic ray detec... - 0 views

phys.org/...hint-dark-results-billion.html

scibyte89 DarkMatter

shared by Mars Base on 04 Apr 13 - No Cached
  • A $2 billion cosmic ray detector on the International Space Station has found the footprint of something that could be dark matter
  • the evidence isn't enough to declare the case closed
  • And after two years, the first evidence came in Wednesday: tantalizing cosmic footprints that seem to have been left by dark matter.
  • ...25 more annotations...
  • the first results from the Alpha Magnetic Spectrometer, known by its acronym AMS,
  • show evidence of new physics phenomena that could be the strange and unknown dark matter or could be energy that originates from pulsars
  • expects a more definitive answer in a matter of months
  • Unraveling the mystery of dark matter could help scientists better understand the composition of our universe and, more particularly, what holds galaxies together
  • The 7-ton detector with a 3-foot magnet ring at its core was sent into space in 2011
  • The device is transmitting its data to CERN, where it is being analyzed
  • For 80 years scientists have theorized the existence of dark matter but have never actually observed it directly
  • They have looked for it in accelerators that smash particles together at high speed
  • deep underground with special detectors
  • no luck
  • there's a third way: looking in space for the results of rare dark matter collisions
  • If particles of dark matter crash and annihilate each other, they should leave a footprint of positrons—the anti-matter version of electrons—at high energy levels
  • found some. But they could also be signs of pulsars
  • What's key is the curve of the plot of those positrons. If the curve is one shape, it points to dark matter. If it's another, it points to pulsars
  • they should know the curve—and the suspect—soon
  • since its installation on 19 May 2011 it has measured over 30 billion cosmic rays at energies up to trillions of electron volts
  • Its permanent magnet and array of precision particle detectors collect and identify charged cosmic rays passing through AMS from the far reaches of space
  • Over its long duration mission on the ISS, AMS will record signals from 16 billion cosmic rays every year and transmit them to Earth for analysis by the AMS Collaboration.
  • In the initial 18 month period of space operations, from 19 May 2011 to 10 December 2012, AMS analyzed 25 billion primary cosmic ray events
  • Of these,
  • 6.8 million, were unambiguously identified as electrons and their antimatter counterpart, positrons.
  • Positrons are clearly distinguished from this background through the robust rejection power of AMS of more than one in one million
  • Currently, the total number of positrons identified by AMS, in excess of 400,000, is the largest number of energetic antimatter particles directly measured and analyzed from space
  • The exact shape of the spectrum, as shown in Figure 2, extended to higher energies, will ultimately determine whether this spectrum originates from the collision of dark matter particles or from pulsars in the galaxy
  • by measuring the ratio between positrons and electrons and by studying the behavior of any excess across the energy spectrum, a better understanding of the origin of dark matter and other physics phenomena can be obtained
Mars Base

After Higgs Boson, scientists prepare for next quantum leap - 0 views

phys.org/...-boson-scientists-quantum.html

scibyte82 HiggsBoson

shared by Mars Base on 16 Feb 13 - No Cached
  • Seven months after its scientists made a landmark discovery that may explain the mysteries of mass, Europe's top physics lab will take a break from smashing invisible particles to recharge for the next leap
  • From Thursday, the cutting-edge facilities at the European Organisation for Nuclear Research (CERN) will begin winding down, then go offline on Saturday for an 18-month upgrade
  • scientists said they were 99.9 percent certain they had found the elusive Higgs Boson,
  • ...7 more annotations...
  • The upgrade will boost the LHC's energy capacity, essential for CERN to confirm definitively that its boson is the Higgs, and allow it to probe new dimensions such as supersymmetry and dark matter
  • We need to increase the energy to look at more physics.
  • Over the past three years, CERN has slammed protons together more than six million billion times
  • espite the shutdown, CERN's researchers won't be taking a breather, as they must trawl through a vast mound of data
  • think a year from now, we'll have more information on the data accumulated over the past three years
  • Last year, the LHC achieved a collision energy level of eight teraelectron volts, an energy measure used in particle physics—up from seven in 2011
  • After it comes back online in 2015, the goal is to take that level to 13 or even 14, with the LHC expected to run for three or four years before another shutdown.
Mars Base

A Twisting Tale of Space Solar Power - 0 views

www.universetoday.com/...ting-tale-of-space-solar-power

scibyte49 solarcell

shared by Mars Base on 30 May 12 - No Cached
  • announced his team’s development of modular devices that could be used to gather solar energy in orbit, working atop an experimental “space web” structure developed by graduate students at the university’s Department of Mechanical and Aerospace Engineering.
  • “By using either microwaves or lasers we would be able to beam the energy back down to earth, directly to specific areas. This would provide a reliable, quality source of energy and would remove the need for storing energy coming from renewable sources on ground as it would provide a constant delivery of solar energy.”
Mars Base

Has Dark Matter Finally Been Found? Big News Soon | Space.com - 0 views

www.space.com/ter-found-nasa-experiment.html

scibyte82 scibyte83 DarkMatter

shared by Mars Base on 19 Feb 13 - No Cached
  • the Alpha Magnetic Spectrometer, a particle collector mounted on the outside of the International Space Station
  • first paper of results
  • in about two weeks
  • ...17 more annotations...
  • e said the results bear on the mystery of dark matter,
  • "It will not be a minor paper,"
  • important enough that the scientists rewrote the paper 30 times before they were satisfied with it
  • it represents a "small step" in figuring out what dark matter is, and perhaps not the final answer
  • Some physics theories suggest that dark matter is made of WIMPS (weakly interacting massive particles), a class of particles that are their own antimatter partner particles
  • When matter and antimatter partners meet, they annihilate each other, so if two WIMPs collided, they would be destroyed, releasing a pair of daughter particles — an electron and its antimatter counterpart, the positron, in the process
  • Alpha Magnetic Spectrometer has the potential to detect the positrons and electrons produced by dark matter annihilations in the Milky Way
  • was installed on the International Space Station in May 2011, and so far, it has detected 25 billion particle events, including about 8 billion electrons and positrons
  • This first science paper will report how many of each were found, and what their energies are
  • If the experiment detected an abundance of positrons peaking at a certain energy, that could indicate a detection of dark matter,
  • while electrons are abundant in the universe around us, there are fewer known processes that could give rise to positrons
  • The smoking gun signature is a rise and then a dramatic fall" in the number of positrons with respect to energy
  • he positrons produced by dark matter annihilation would have a very specific energy, depending on the mass of the WIMPs making up dark matter
  • Another telling sign will be the question of whether positrons appear to be coming from one direction in space, or from all around
  • f they're from dark matter, scientists expect them to be spread evenly through space, but if they're created by some normal astrophysical process, such as a star explosion, then they would originate in a single direction
  • There is a lot of stuff that can mimic dark matter,"
  • Regardless of whether AMS has found dark matter yet, the scientists said they expected the question of dark matter's origin to become clearer soon
Mars Base

Triton: A subsurface ocean? - 0 views

phys.org/...9-triton-subsurface-ocean.html

sibyte62 Tritan

shared by Mars Base on 06 Sep 12 - No Cached
  • Neptune's largest moon Triton is most likely a captured Kuiper Belt Object. The capture of icy Triton and the subsequent taming of its orbit likely led to the formation of a subsurface ocean through tidal heating. New research suggests that this ocean could still exist today.
  • much about Neptune's largest moon still remains a mystery
  • Voyager 2 flyby in 1989 offered a quick peak at the satellite, and revealed a surface composition comprised mainly of water ice
  • ...22 more annotations...
  • also had nitrogen, methane, and carbon dioxide
  • density is quite high, it is suspected that it has a large core of silicate rock
  • possible that a liquid ocean could have formed between the rocky core and icy surface shell
  • Triton has a unique property among large solar system moons; it has a retrograde orbit
  • planets and their moons must also orbit in this same direction
  • Planets form from a circumstellar disc of dust and gas
  • These orbits are known as prograde
  • retrograde orbit of Triton means that it most likely did not form around Neptune.
  • Triton likely originated in the Kuiper Belt, beyond the orbit of Neptune, and was sent hurtling inwards until it was captured by Neptune's gravity
  • Directly after capture, the moon would have been in a highly elliptical, eccentric orbit
  • This type of orbit would have raised large tides on the moon, and the friction of these tides would have caused energy to be lost
  • energy loss is converted into heat
  • melt some of the icy interior and form an ocean beneath the ice shell
  • energy loss from tides is also responsible for gradually changing Triton's orbit from an ellipse to a circle
  • there
  • also radiogenic heating. This is heat that is caused by the decay of radioactive isotopes within a moon or planet, and this process can create heat for billions of years
  • Radiogenic heating contributes several times more heat to Triton's interior than tidal heating
  • this heat alone is not sufficient to keep the subsurface ocean in a liquid state over 4.5 billion years
  • One model of Triton’s interior. 70 to 80 percent rock (1), with the remainder being water ice (2) and an outer layer of methane and nitrogen ice (3). This is also believed to be the general interior configuration for the ice dwarf Pluto. Credit: Wikipedia
  • The exact point in time when Triton was captured by Neptune, along with the length of the time it took the orbit to become circularized are unknown
  • orbit is currently almost exactly circular
  • the exact size of Triton's rocky core is unknown
Mars Base

Tiny Sun Activity Changes Affect Earth's Climate | Solar Sunspot Cycle | Space.com - 0 views

www.space.com/ar-activity-earth-climate.html

scibyte78 sun

shared by Mars Base on 18 Jan 13 - No Cached
  • Even small changes in solar activity can impact Earth's climate in significant and surprisingly complex ways, researchers say.
  • The sun is a constant star when compared with many others in the galaxy
  • ome stars pulsate dramatically, varying wildly in size and brightness and even exploding
  • ...24 more annotations...
  • In comparison, the sun varies in the amount of light it emits by only 0.1 percent over the course of a relatively stable 11-year-long pattern known as the solar cycle.
  • "the light reaching the top of the Earth's atmosphere provides about 2,500 times as much energy as the total of all other sources combined,"
  • even 0.1 percent of the amount of light the sun emits exceeds all other energy sources the Earth's atmosphere sees combined, such as the radioactivity naturally emitted from Earth's core,
  • Many of the ways the scientists proposed these fluctuations in solar activity could influence Earth were complicated in nature.
  • , solar energetic particles and cosmic rays could reduce ozone levels in the stratosphere
  • in turn alters the behavior of the atmosphere below it, perhaps even pushing storms on the surface off cours
  • "In the lower stratosphere, the presence of ozone causes a local warming because of the breakup of ozone molecules by ultraviolet light,
  • When the ozone is removed, "the stratosphere there becomes cooler, increasing the temperature contrast between the tropics and the polar region
  • contrast in temperatures in the stratosphere and the upper troposphere leads to instabilities in the atmospheric flow west to east.
  • feed the strength of jet streams, ultimately altering flows in the upper troposphere, the layer of atmosphere closest to Earth's surface.
  • alter the distribution of storms over the middle latitudes
  • the sun might have a role to play in this kind of process. I would have to say this would be a very difficult mechanism to prove in climate models
  • climate scientist Gerald Meehl at the National Center for Atmospheric Research and his colleagues suggest that solar variability is leaving a definite imprint on climate, especially in the Pacific Ocean.
  • When researchers look at sea surface temperature data during sunspot peak years, the tropical Pacific showed a pattern very much like that expected with La Niña,
  • cyclical cooling of the Pacific Ocean that regularly affects climate worldwide, with sunspot peak years leading to a cooling of almost 1 degree Celsius (1.8 degrees Fahrenheit) in the equatorial eastern Pacific
  • peaks in the sunspot cycle were linked with increased precipitation in a number of areas across the globe, as well as above-normal sea-level pressure in the mid-latitude North and South Pacific.
  • Scientists have also often speculated whether the Maunder Minimum, a 70-year dearth of sunspots in the late 17th to early 18th century, was linked with the coldest part of the Little Ice Age, during which Europe and North America experienced bitterly cold winter
  • This regional cooling might be linked with a drop in the sun's extreme ultraviolet radiation.
  • t, the sun could currently be on the cusp of a miniature version of the Maunder Minimum, since the current solar cycle is the weakest in more than 50 years.
  • Although the sun is the main source of heat for Earth, the researchers note that solar variability may have more of a regional effect than a global one
  • While the sun is by far the dominant energy source powering our climate system, do not assume that it is causing much of recent climate changes. It's pretty stabl
  • Ancient signals of climate such as tree rings and ice cores might also help shed light on the link between the sun and climate
  • Since variations in Earth's magnetic field and atmospheric circulation might disrupt this evidence on Earth,
  • a better long-term record of solar radiation might lie in the rocks and sediments of the moon or Mar
Mars Base

Rocket powered by nuclear fusion could send humans to Mars - 0 views

phys.org/...red-nuclear-fusion-humans.html

scibyte90 MarsMission

shared by Mars Base on 11 Apr 13 - No Cached
  • researchers and scientists
  • are building components of a fusion-powered rocket aimed to clear many of the hurdles that block deep space travel, including long times in transit, exorbitant costs and health risks
  • funded through NASA's Innovative Advanced Concepts Program
  • ...25 more annotations...
  • Last month
  • presented their mission analysis for a trip to Mars, along with detailed computer modeling and initial experimental results
  • one of a handful of projects awarded a second round of funding last fall after already receiving phase-one money in a field of 15 projects chosen from more than 700 proposals
  • NASA estimates a round-trip human expedition to Mars would take more than four years using current technology
  • team have published papers calculating the potential for 30- and 90-day expeditions to Mars using a rocket powered by fusion, which would make the trip more practical and less costly
  • They have demonstrated successful lab tests of all portions of the process
  • Now, the key will be combining each isolated test into a final experiment that produces fusion using this technology
  • The research team has developed a type of plasma that is encased in its own magnetic field
  • Nuclear fusion occurs when this plasma is compressed to high pressure with a magnetic field.
  • The team has successfully tested this technique in the lab.
  • a small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.
  • power a rocket, the team has devised a system in which a powerful magnetic field causes large metal rings to implode around this plasma, compressing it to a fusion state
  • The converging rings merge to form a shell that ignites the fusion, but only for a few microseconds
  • enough energy is released from the fusion reactions to quickly heat and ionize the shell
  • This super-heated, ionized metal is ejected out of the rocket nozzle at a high velocity. This process is repeated every minute or so, propelling the spacecraft
  • successfully demonstrated the metal-crushing process
  • The team had a sample of the collapsed, fist-sized aluminum ring resulting from one of those tests on hand for people to see and touch at the recent NASA symposium
  • Now, the team is working to bring it all together by using the technology to compress the plasma and create nuclear fusion
  • With the flip of a switch, the capacitors are simultaneously triggered to deliver 1 million amps of electricity for a fraction of a second to the magnet, which quickly compresses the metal ring.
  • The mechanical process and equipment used are reasonably straightforward
  • In actual space travel, scientists would use lithium metal as the crushing rings to power the rocket. Lithium is very reactive, and for lab-testing purposes, aluminum works just as well
  • Nuclear fusion may draw concern because of its application in nuclear bombs, but its use in this scenario is very different
  • The fusion energy for powering a rocket would be reduced by a factor of 1 billion from a hydrogen bomb, too little to create a significant explosion
  • Also,
  • concept uses a strong magnetic field to contain the fusion fuel and guide it safely away from the spacecraft and any passengers within
Mars Base

Scientists sense breakthroughs in dark-matter mystery - 0 views

phys.org/...oughs-dark-matter-mystery.html

scibyte82 scibyte83 DarkMatter

shared by Mars Base on 19 Feb 13 - No Cached
  • Dark matter throws down the gauntlet to the so-called Standard Model of physics.
  • Elegant and useful for identifying the stable of particles and forces that regulate our daily life, the Standard Model only tells part of the cosmic story
  • it does not explain gravity, although we know how to measure gravity and exploit it for our needs
  • ...13 more annotations...
  • the Standard Model has been found to account for only around four or five percent of the stuff in the Universe
  • dark matter, making up 23 percent, and dark energy, an enigmatic force that appears to drive the expansion of the Universe, which accounts for around 72 or 73 percent.
  • The dark matter theory was born 80 years ago when Swiss astrophysicist Fritz Zwicky discovered that there was not enough mass in observable stars or galaxies to allow the force of gravity to hold them together
  • why dark matter has six times the energy that is in ordinary matter
  • could be 10 trillions times bigger
  • first results will be published in two to three weeks
  • High-powered instruments track cosmic particles
  • To track these phantom particles, physicists rely on several methods and tools
  • One is the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station (ISS), which captures gamma rays coming from collisions of dark matter particles.
  • only suggesting that these highly anticipated results would give humans a better idea about the nature of dark matter
  • Another tool used by the scientists is the South Pole Neutrino Observatory, which tracks subatomic particles known as neutrinos, which, according to physicists, are created when dark matter passes through the Sun and interacts with protons
  • Another
  • is the Large Hadron Collider (LHC) near Geneva, the biggest particle smasher in the world
Mars Base

CERN physicists report strong evidence of Higgs boson (w/ live video from CERN) - 0 views

phys.org/...-strong-evidence-particle.html

scibyte53 HiggsBoson

shared by Mars Base on 05 Jul 12 - No Cached
  • Joe Incandela, leader of one of the teams known as CMS, told scientists at the European Center for Nuclear Research, or CERN, that his team of 2,100 scientists has "observed" a new particle that is a boson
  • data as consistent with the elusive Higgs boson
  • stopped short of definitively declaring discovery of the Higgs boson.
  • ...15 more annotations...
  • they have discovered a new particle that is consistent with the long-sought Higgs boson
  • which is believed to give all matter in the universe size and shape
  • We observe in our data clear signs of a new particle, at the level of 5 sigma, in the mass region around 126 GeV
  • it must be a boson and it’s the heaviest boson ever found
  • A more complete picture of today’s observations will emerge later this year after the LHC provides the experiments with more data.
  • The next step will be to determine the precise nature of the particle
  • LHC will continue running until the end of this year, and is expected to deliver twice as much data as we have so far
  • After that, it will be upgraded, and will be able to run at higher energy, which will help with the measurements.
  • . In the Standard Model (the simplest theory which describes the fundamental subatomic particles and the forces between them) it is hypothesized that there is only one Higgs Boson
  • in the Supersymmetric Model (which, unlike the Standard Model, incorporates the physics of dark energy and the full theory of gravitation) there could be up to five Higgs Boson
  • how will they know if it is one of many?
  • detailed decay properties of a supersymmetric Higgs Boson are different from those of the Standard Model version. Therefore, with sufficiently precise data we will be able to tell the difference
  • Supersymmetry is an extension of the Standard Model, rather than a replacement
  • The Standard Model will always remain as an excellent description of Nature at energies below those explored at the LHC
  • similar to the way in which Einstein’s General Relativity is the best description of very strong gravitational fields, but Newton’s gravity works perfectly well for almost all normal situations.
Mars Base

Researchers find evidence of photosynthesis-like process in aphids - 0 views

phys.org/...hotosynthesis-like-aphids.html

scibyte60

shared by Mars Base on 21 Aug 12 - No Cached
  • In plants, algae and some types of bacteria and fungi, sunlight is converted to chemical energy in a process we all know as photosynthesis
  • water and carbon dioxide are also converted to oxygen
  • Now it appears that a type of aphid, a small insect, is able to do something similar, minus the water and carbon dioxide conversion
  • ...12 more annotations...
  • Researchers at the Sophia Agrobiotech Institute in France, have found that not only do aphids produce carotenoids, but the amount they produce seems to be directly influenced by the amount of sunshine they receive in their daily life
  • Carotenoids are pigments that in most animals are obtained via consumption of other organisms that create it via photosynthesis
  • Aphids
  • are able to synthesize them all by themselves, making them stand out
  • Researchers aren’t sure why they do so, but many other animals rely on carotenoids to help bolster a strong immunity system
  • carotenoids in aphids are responsible for their color
  • high levels are green, those with very low levels are white, and those in-between are orange.
  • In this new research the team found that the levels of carotenoids in the aphids appeared to correlate with levels of adenosine triphosphate (ATP),
  • the way to measure the transfer of energy in living things
  • higher the level of carotenoids were the more ATP was present
  • when the team moved orange aphids in and out of direct sunlight, levels of carotenoids and ATP rose and sunk
  • suggesting the insect was getting energy directly through such exposure
Mars Base

MESSENGER Solves Solar Flare Mystery - 0 views

www.universetoday.com/...ger-solves-solar-flare-mystery

scibyte21 messenger sun

shared by Mars Base on 10 Nov 11 - No Cached
  • 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
  • ...17 more annotations...
  • 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.
  • forms an extended seed population in interplanetary space that can be further accelerated by the massive shock waves produced by the flares
  • another population results from the decay of the neutrons near the sun
  • About 90 percent of all ions produced by a solar flare remain locked to the sun on closed magnetic lines
  • 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
Mars Base

Heart-powered pacemaker could one day eliminate battery-replacement surgery - 0 views

www.physorg.com/...ttery-replacement-surgery.html

scibyte36 heart health

shared by Mars Base on 04 Mar 12 - No Cached
  • A new power scheme for cardiac pacemakers turns to an unlikely source: vibrations from heartbeats themselves.
  • a device that harvests energy from the reverberation of heartbeats through the chest and converts it to electricity to run a pacemaker or an implanted defibrillator.
  • new energy harvester could save patients from repeated surgeries. That's the only way today to replace the batteries, which last five to 10 years.
  • ...9 more annotations...
  • use ambient vibrations that are typically wasted and convert them to electrical energy
  • researchers haven't built a prototype yet
  • made detailed blueprints and run simulations demonstrating that the concept would work
  • A hundredth-of-an-inch thin slice of a special "piezoelectric" ceramic material would essentially catch heartbeat vibrations and briefly expand in response
  • Piezoelectric materials' claim to fame is that they can convert mechanical stress (which causes them to expand) into an electric voltage.
  • have precisely engineered the ceramic layer to a shape that can harvest vibrations across a broad range of frequencies
  • incorporated magnets, whose additional force field can drastically boost the electric signal that results from the vibrations.
  • new device could generate 10 microwatts of power, which is about eight times the amount a pacemaker needs to operate
  • originally designed the harvester for light unmanned airplanes, where it could generate power from wing vibrations
Mars Base

Tevatron experiments report latest results in search for Higgs boson - 0 views

www.physorg.com/...atest-results-higgs-boson.html

scibyte37 HiggsBoson

shared by Mars Base on 07 Mar 12 - No Cached
  • New measurements
  • indicate that the elusive Higgs boson may nearly be cornered.
  • two independent experiments see hints of a Higgs boson.
  • ...24 more annotations...
  • collaborations found excesses in their data that might be interpreted as coming from a Higgs boson with a mass in the region of 115 to 135 GeV.
  • claim evidence of a new particle only if the probability that the data could be due to a statistical fluctuation is less than 1 in 740
  • claimed only if that probability is less than 1 in 3.5 million, or five sigmas.
  • stringent constraints established by earlier direct and indirect measurements made by CERN’s Large Hadron Collider, the Tevatron, and other accelerators,
  • place the mass of the Higgs boson within the range of 115 to 127 GeV
  • consistent with the December 2011 announcement of excesses seen in that range by LHC experiments, which searched for the Higgs in different decay patterns
  • None of the
  • experiments
  • are strong enough to claim evidence for the Higgs boson
  • This is an important milestone for the Tevatron experiments, and demonstrates the continuing importance of independent measurements
  • the latest result in a decade-long search by teams of physicists at the Tevatron
  • two collaborations independently combed through hundreds of trillions of proton-antiproton collisions recorded by their experiments to arrive at this exciting result
  • Higgs bosons, if they exist, are short-lived and can decay in many different ways.
  • Higgs can decay into different combinations of particles
  • still much work ahead before the scientific community can say for sure whether the Higgs boson exists
  • According to the Standard Model, the theory that explains and predicts how nature’s building blocks behave and interact with each other, the Higgs boson gives mass to other particles
  • Physicists have known for a long time that the Higgs or something like it must exist
  • Higgs boson is created in a high-energy particle collision, it immediately decays into lighter more stable particles
  • physicists retraced the path of these secondary particles and ruled out processes that mimic its signal.
  • Tevatron was a proton/anti-proton collider, with a maximum center of mass energy of 2 TeV,
  • LHC is a proton/proton collider that will ultimately reach 14 TeV
  • two accelerators collide different pairs of particles at different energies and produce different types of backgrounds
  • search strategies are different
  • search for the Higgs boson by the Tevatron and LHC experiments is like two people taking a picture of a park from different vantage points
Mars Base

Germany sets weekend record for solar power - 0 views

phys.org/...rmany-weekend-solar-power.html

scibyte49 solarcell

shared by Mars Base on 30 May 12 - No Cached
  • Solar power plants in Germany have set a new record. “Never before anywhere has a country produced as much photovoltaic electricity,"
  • plants peaked at 22 gigawatts of output for a few hours over the weekend, on Friday and Saturday
  • they yielded almost half the country's energy mid-day electricity needs
  • ...3 more annotations...
  • 22 gigawatts is up from 14 GW a year ago. Also, this 22 gigawatts of output is equal to about 20 nuclear plants.
  • 2012 Environment Ministry report showed that German taxpayers pay an extra four billion euros per year on top of their electricity bills to support solar power
  • The new record-breaking figures from Germany, however, do not quiet some energy experts who stress that without good storage strategies for excess power, such record-breaking numbers are not meaningful. They say the real point is to get consistently large percentages of power from renewable sources.
Mars Base

Invention Awards 2014: Charge Gadgets With Your Footsteps | Popular Science - 0 views

www.popsci.com/...-charge-gadgets-your-footsteps

scibyte129

shared by Mars Base on 04 May 14 - No Cached
  • of a hiker’s heel releases enough energy to illuminate a light bulb
  • Matt Stanton, an engineer and avid backpacker, created a shoe insole that stores it as electricity
  • Instead of using piezoelectric and other inefficient, bulky methods of generating electricity, the pair shrunk down components similar to those found in hand-cranked flashlights.
  • ...7 more annotations...
  • The result is a near standard–size removable insole that weighs less than five ounces, including a battery pack, and charges electronics via USB.
  • current version, to be released later this year, requires a lengthy 15-mile walk to charge a smartphone.
  • the company is working toward a design that can charge an iPhone after less than five miles of hiking and withstand about 100 million footsteps of wear and tear. 
  • How It Works
  • 1) A drivetrain converts the energy of heel strikes into rotational energy, spinning magnetic rotors
  • 2) The motion of the rotors induces an electrical current within coils of wire
  • 3) Electricity travels along a wire and into a lithium-ion polymer battery pack on a wearer’s shoelaces.
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