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Mars Base

Mystery of Moon's Lost Magnetism Solved? | Magnetic Moon Rocks Caused by Lunar Dynamo |... - 0 views

www.space.com/gnetic-field-lunar-dynamo.html

moon magnetism scibyte21

shared by Mars Base on 10 Nov 11 - No Cached
  • One of the abiding mysteries of our moon is why it apparently once had a magnetic field
  • When Apollo astronauts brought back samples of moon rocks from their lunar landing missions
  • some of them shocked scientists by being magnetic.
  • ...16 more annotations...
  • This can happen to rocks with the right minerals inside them, if they cool in the presence of a magnetic field
  • A magnetic field is generated by what's called a dynamo, which is caused by the fluid motion of a conducting material, such as liquid iron
  • the moon isn't large enough for convection to take place
  • In one new proposal
  • The strength of this stirring is determined by the angle between the core and the mantle
  • researchers think this happens because the moon's core and its mantle rotate around slightly different axes
  • suggest that the moon's solid-rock middle layer, called its mantle, stirs up its liquid iron core
  • because the tidal gravitational tug from the Earth causes the moon's mantle to rotate differently than the core
  • This model would explain why the moon used to have a magnetic field, but no longer does
  • researchers estimate the lunar magnetic field might have lasted for about a billion years
  • isn't the only possible solution to the moon's mystery
  • another explanation for the ancient lunar magnetic field.
  • suggests that the moon's mantle might have stirred up the liquid in its core
  • Instead of tidal interactions between the Earth and the moon, the researchers posit that impacts by large space rocks slamming into the moon have changed its rotation rate
  • would induce brief periods of especially strong stirring of the core, creating spikes of a magnetic field on the moon
  • either option may be correct, it's also possible that both mechanisms played a role in causing an ancient magnetic field on the moon
Mars Base

Physicists create synthetic magnetic monopole predicted more than 80 years ago - 0 views

phys.org/...c-magnetic-monopole-years.html

scibyte118

shared by Mars Base on 30 Jan 14 - No Cached
  • Nearly 85 years
  • physicist
  • predicted the possibility
  • ...20 more annotations...
  • identified and photographed synthetic magnetic monopoles
  • The groundbreaking accomplishment paves the way for the detection of the particles in nature
  • "The creation of a synthetic magnetic monopole should provide us with unprecedented insight into aspects of the natural magnetic monopole—if indeed it exists,"
  • To be able to confirm the work of one of the most famous physicists is probably a once-in-a-lifetime opportunity
  • Ordinarily, magnetic poles come in pairs: they have both a north pole and a south pole
  • a magnetic monopole is a magnetic particle possessing only a single, isolated pole—a north pole without a south pole, or vice versa
  • . In 1931,
  • published a paper that explored the nature of these monopoles in the context of quantum mechanics
  • Despite extensive experimental searches since then, in everything from lunar samples—moon rock—to ancient fossilized minerals, no observation of a naturally-occurring magnetic monopole has yet been confirmed
  • team adopted an innovative approach to investigating
  • theory, creating and identifying synthetic magnetic monopoles
  • an artificial magnetic field generated by a Bose-Einstein condensate, an extremely cold atomic gas tens of billionths of a degree warmer than absolute zero.
  • The team relied upon theoretical work
  • that suggested a particular sequence of changing external magnetic fields could lead to the creation of the synthetic monopole
  • Their experiments subsequently took place in the atomic refrigerator built
  • in his basement laboratory in the Merrill Science Center
  • After resolving many technical challenges, the team was rewarded with photographs that confirmed the monopoles' presence at the ends of tiny quantum whirlpools within the ultracold gas.
  • The result proves experimentally that
  • structures do exist in nature
  • Physics Professor David S. Hall '91 and Aalto University (Finland)
Mars Base

A Big Magnet in a Small Fish - ScienceNOW - 0 views

news.sciencemag.org/...ig-magnet-in-a-small-fish.html

scibyte54 Fish

shared by Mars Base on 12 Jul 12 - No Cached
  • After spending 3 years at sea and traveling up to 300 kilometers away from home, a rainbow trout can swim straight back to its original hatching ground, following freshwater streams inland and rarely heading in the wrong direction
  • likely relies on many senses; the fish have superb eyesight and smell
  • trout also seem to rely on Earth's magnetic fields, which point them in the right direction
  • ...6 more annotations...
  • the first time in any animal, scientists have isolated magnetic cells in the fish that respond to these fields
  • may help researchers get to the root of magnetic sensing in a variety of creatures, including birds.
  • Previous research has shown that many species of fish, as well as migratory birds, have the ability to detect differences in magnetic field strengths, which vary around the
  • magnetism in each cell was tens to hundreds of times stronger than researchers had hypothesized
  • suggests that the fish may be able to detect not only the direction of North based on magnetism, but small differences in magnetic field strength that can give them more detailed information about their precise latitude and longitude
  • between one and four cells that rotated in turn with the rotating magnetic field. The team transferred the rotating cells to individual glass slides to study them further under the microscope.
Mars Base

Voyager 1 encounters new region in deep space, NASA says - 0 views

phys.org/...ounters-region-deep-space.html

scibyte73 Voyager1

shared by Mars Base on 04 Dec 12 - No Cached
  • Voyager 1 spacecraft has entered a new region
  • that scientists feel is the final area the spacecraft has to cross before reaching interstellar space
  • Scientists refer to this new region as a magnetic highway for charged particles because our sun's magnetic field lines are connected to interstellar magnetic field lines
  • ...4 more annotations...
  • infers this region is still inside our solar bubble because the direction of the magnetic field lines has not changed
  • data from two onboard instruments that measure charged particles showed the spacecraft first entered this magnetic highway region on July 28, 2012
  • We are in a magnetic region unlike any we've been in before—about 10 times more intense than before the termination shock—but the magnetic field data show no indication we're in interstellar space
  • The magnetic field data turned out to be the key to pinpointing when we crossed the termination shock. And we expect these data will tell us when we first reach interstellar space."
Mars Base

Could Pulses in Earth's Magnetic Field Forecast Earthquakes? | Science/AAAS | News - 0 views

news.sciencemag.org/...tic-field-forecast-earthquakes

scibyte134 earthquakes

shared by Mars Base on 07 Jun 14 - No Cached
  • In the days leading up to some recent moderate-sized earthquakes, instruments nearby have picked up brief low-frequency pulses in Earth’s magnetic field
  • A few scientists have proposed that such pulses, which seemed to become stronger and more frequent just before the earthquakes occurred, could serve as an early warning sign for impending seismic activity
  • Now, a team has come up with a model for how these magnetic pulses might be generated, though some critics say they may have a humanmade origin.
  • ...32 more annotations...
  • Brief fluctuations in Earth’s magnetic field have been detected before many earthquakes in the past 50 years
  • Friedemann Freund, a crystallographer at San Jose State University
  • in the weeks before a magnitude-5.4 quake struck about 15 kilometers northeast of San Jose in October 2007, an instrument near the epicenter sensed a number of unusual magnetic pulses
  • Those blips became more frequent as the day of the earthquake approached, Freund says
  • recently, prior to several medium- to moderate-sized quakes in Peru, two sensitive magnetometers recorded the same sort of pulses
  • how such pulses could be generated
  • suggest that these blips stem from microscopic changes in crystals in rocks under seismic stress deep within Earth
  • In many types of rocks, particularly volcanic rocks that have substantial amounts of water locked inside them, crystals are chock-full of oxygen-oxygen bonds called peroxy bonds
  • (These bonds formed long ago, after chemical changes split some of the water molecules, freeing the hydrogen atoms to bond together and then diffuse out of the rocks as gas.)
  • When those rocks are squeezed, say, by the sides of a fault zone scraping past one another, some of the peroxy bonds break
  • Those broken bonds release negatively charged electrons, which remain trapped in place, and create positively charged “holes” in the crystal
  • his team propose that the same process might be happening within Earth’s crust
  • As stress on large volumes of rock builds in advance of an impending quake, many, many of these electrical holes are created inside them
  • the mass migration of such holes that creates the large electrical currents responsible for generating the low-frequency magnetic pulses that make their way to detectors on Earth’s surface
  • they say
  • some critics of his model have proposed
  • lightning
  • as an alternative explanation
  • he notes, with data from the two sensors in Peru he and his colleagues were able to pinpoint the strongest of those pulses as originating within a few kilometers of the epicenters of subsequent quakes
  • For now, Freund admits, the team’s model is preliminary: The paper has been submitted to a journal and is now being reviewed by other scientists.
  • two instruments aren’t sufficient to pinpoint the location of an event; to truly “triangulate” an event you need at least three sensors
  • “I’m concerned that the pulses are not originating deep within the Earth.”
  • “This paper only makes sense if the observations [of magnetic pulses] are good,”
  • John Ebel, a seismologist at Boston College, who wasn’t involved in the research
  • the blips may have some inexplicable humanmade origin
  • Decades ago
  • his Boston-based magnetometers started picking up a series of odd pulses every morning.
  • Eventually
  • identified
  • It was the engineers cranking up Boston’s trolley cars at a rail yard a few kilometers away from the instruments
  • Even if the magnetic pulses originate within Earth along seismic zones under stress, Freund says, the blips don’t always foretell a quake
  • It’s more likely to be the pattern of pulses—and, in particular, changes in their size and frequency—that Freund and his colleagues say might offer scientists a crystal ball for impending temblors
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

Moon Patterns Explained - Science News - 0 views

www.sciencenews.org/...Moon_patterns_explained

GrabBag LunarSwirls

shared by Mars Base on 11 Jul 12 - No Cached
  • New research suggests that swirling designs on the dusty lunar surface might be the product of electric fields generated by pockets of magnetic bubbles.
  • looking at these strange, mysterious structures since the invention of the telescope
  • long suspected that weak magnetic fields near the moon’s surface might shape the looping patterns
  • ...4 more annotations...
  • created a scaled-down laboratory version to find out if man-made magnetic bubbles could also deflect rushing rivers of particles
  • used a device called a solar wind tunnel to shoot a jet of blazing particles down a tube
  • a thin electric field formed around the magnet, shielding it — and anything behind it — from the scorching flow
  • if a tiny magnet — only slightly larger than an eraser tip — could make a protective electric skin, the moon’s much larger magnetic bubbles might also be able to
Chris Fisher

Probes Suggest Magnet Bubbles At Solar System Edge - 0 views

voyager.jpl.nasa.gov/...probes_suggest.html

scibyte waves sun magnetic voyager

shared by Chris Fisher on 17 Dec 11 - No Cached
  • While using a new computer model to analyze Voyager data, scientists found the sun's distant magnetic field is made up of bubbles approximately 100 million miles (160 million kilometers) wide.
  • The new model suggests the field lines are broken up into self-contained structures disconnected from the solar magnetic field. The findings are described in the June 9 edition of the Astrophysical Journal.
  • "The sun's magnetic field extends all the way to the edge of the solar system," said astronomer Merav Opher of Boston University. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are, the folds of the skirt bunch up."
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

Big Solar Storm Packed Small Punch | Solar Flare 2012 | Space.com - 0 views

www.space.com/solar-storm-earth-effects.html

scibyte37 sun

shared by Mars Base on 09 Mar 12 - No Cached
  • triggered weaker-than-expected disruptions
  • Early forecasts showed that the oncoming CME could boost solar radiation in space and trigger geomagnetic storms on Earth, potentially disrupting satellites, power grids and other electronic infrastructure.
  • effects of the solar tempest have been milder than scientists originally predicted
  • ...5 more annotations...
  • due to the orientation of the CME and Earth's magnetic fields
  • "If it's oriented more southward, which is opposite to Earth, then we expect a stronger storm, but it appears that this one was very much north oriented
  • orientation of the magnetic field in the CME is a big determining factor for how strong or weak the event is going to be
  • coronal mass ejection has a cloud of particles, but also embedded in that is a magnetic field structure
  • while it hasn't packed much of a punch so far, this ongoing solar storm is the largest one scientists have seen in more than five years
Mars Base

Did NASA's Voyager 1 Spacecraft Just Exit the Solar System? | Space.com - 0 views

www.space.com/r-spacecraft-solar-system.html

scibyte66 scibyte67 Voyager1

shared by Mars Base on 09 Oct 12 - No Cached
  • Scientists are crunching one more set of numbers to find out for sure.
  • New data from the spacecraft indicate that the historic moment of its exit from the solar system might have come and gone two months ago
  • For two years now, data beamed back to Earth by Voyager 1 has hinted at its close approach to the edge of the solar system, a pressure boundary called the heliopaus
  • ...20 more annotations...
  • bubble of electrically charged particles blowing outward from the sun (called the heliosphere) exactly counterbalances the inward pressure of the gas and dust from interstellar space, causing equilibrium between the two
  • scientists have had trouble figuring out what, exactly, happens at or near this boundary — making it hard to tell whether Voyager has crossed it
  • In 2010, Voyager passed the point where the solar wind, a stream of charged particles flowing outward from the sun, seemed to
  • indicated that the wind had suddenly died down, and all the surrounding solar particles were at a standstill
  • "stagnation region" came as a surprise
  • expected to see the solar wind veer sideways
  • the perplexing collapse of the solar wind at the edge of the heliosphere left them without a working model for the outer solar system
  • no well-established criteria of what constitutes exit from the heliosphere
  • "All theoretical models have been found wanting."
  • a space scientist at Johns Hopkins who works with Voyager 1 data, said that in any model of the heliopause, an object exiting through it should experience three changes: a sharp rise in the number of collisions with cosmic rays (high-energy particles from space), a dramatic drop in the number of collisions with charged particles from the sun, and a change in the direction of the surrounding magnetic field.
  • Based on two of those criteria, Voyager 1 looks as if it passed through the heliopause at the end of the summer
  • The level of these cosmic ray collisions jumped significantly in late August.
  • spacecraft has experienced a steady rise in the number of collisions with particles whose energies are greater than 70 Mega-electron-volts, indicating they are probably cosmic rays emanating from supernova explosions far beyond the solar system
  • in late August, cosmic ray collisions sharply rose, and solar particle collisions sharply fell: two indicators of a transition through the heliopause
  • To officially declare Voyager's crossing, the scientists need to check if the third condition holds
  • change in magnetic field direction
  • e interstellar field beyond the influence of the sun) is critical because, even though there is debate among astrophysicists as to what direction the field will lie in
  • unlikely that it is the direction that we have been seeing at Voyager 1 throughout the most recent years
  • scientists could not say when the magnetic field analysis would be finished. But when it is
  • Once we have a consensus within the team we will inform NASA for a proper announcement,
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

Solar Tornadoes Dance Across Sun's Surface in NASA Video | Sun Tornado & Solar Flares |... - 0 views

www.space.com/-tornadoes-nasa-video-sdo.html

FebMedia

shared by Mars Base on 18 Feb 12 - No Cached
  • The tornado-like eruptions of super-hot plasma were spotted by NASA's Solar Dynamics Observatory, which is constantly recording high-definition videos of the sun.
  • shows swirling fountains of plasma creeping across the surface of the sun during a 30-hour period between Feb. 7 and 8.
  • unlike tornadoes on Earth, which are wind-driven phenomena, the sun's plasma tornadoes are shaped by the powerful magnetic field of our star.
  • ...10 more annotations...
  • active region rotating into view provides a bright backdrop to the gyrating streams of plasma
  • particles are being pulled this way and that by competing magnetic forces
  • tracking along strands of magnetic field lines
  • cooler plasma material appears as darker spots on a bright background
  • SDO spacecraft recorded the video in the extreme ultraviolet range of the light spectrum, giving the movie an eerie yellow hue.
  • released
  • SDO video
  • mark the second anniversary
  • on a five-year mission to record high-definition videos of the sun to help astronomers better understand how changes in the sun's solar weather cycle can affect life on Earth.
  • launched on Feb. 11, 2010
Mars Base

NASA - NASA's Voyager Hits New Region at Solar System Edge - 0 views

www.nasa.gov/...voyager20111205.html

scibyte51 Voyager1 voyager

shared by Mars Base on 17 Jun 12 - No Cached
  • the wind of charged particles streaming out from our sun has calmed, our solar system's magnetic field has piled up, and higher-energy particles from inside our solar system appear to be leaking out into interstellar space.
  • Voyager 1 is about 11 billion miles (18 billion kilometers) from the sun
  • The data do not reveal exactly when Voyager 1 will make it past the edge of the solar atmosphere into interstellar space, but suggest it will be in a few months to a few years.
  • ...3 more annotations...
  • During this past year, Voyager's magnetometer also detected a doubling in the intensity of the magnetic field
  • Like cars piling up at a clogged freeway off-ramp, the increased intensity of the magnetic field shows that inward pressure from interstellar space is compacting it.
  • Voyager has detected a 100-fold increase in the intensity of high-energy electrons from elsewhere in the galaxy diffusing into our solar system from outside, which is another indication of the approaching boundary.
Mars Base

Mysterious Extragalactic Explosions Baffle Astronomers | Fast Radio Bursts | Space.com - 0 views

www.space.com/-radio-explosions-mystery.html

scibyte100 RadioSignal

shared by Mars Base on 07 Jul 13 - No Cached
  • known as fast radio bursts (FRBs), above the plane of our Milky Way Galaxy.
  • These bursts gave off more energy in a millisecond than the sun does in 300,000 years
  • The bursts ranged from 5.5 to 10 billion light-years away, meaning it took the light from some of them 10 billion years to reach Earth. (The Big Bang 
  • ...17 more annotations...
  • occurred 13.8 billion years ago
  • These newfound objects allowed the researchers to calculate that an FRB should occur once every 10 seconds
  • whether the new signals came from inside or outside the Milky Way.
  • they studied how the radio waves were affected by the material they pass through — a technique that could allow these new objects to shed light on the components of space.
  • As radio waves travel in space, they are stretched and slowed by the ionized material through which they move
  • Using models, the team concluded that the FRBs traveled billions of light-years — much farther than the edge of Earth's galaxy
  • the source is likely located in another galaxy
  • They are so bright and narrow that we can limit the size of the emission region at the source to just a few hundred kilometers
  • Although the explosions are brief, the astronomers can pinpoint the bursts' locations pretty accurately
  • No corresponding object could be observed in optical, gamma or X-ray wavelengths, so the explosions' origins remain unknown to scientists
  • Possible sources
  • intersecting magnetic fields from two neutron stars, extremely dense city-size bodies packing the mass of the sun.
  • A special kind of supernova orbited by a neutron star could potentially produce radio bursts as the star's magnetic field interacts with the explosion of the supernova
  • such combinations would be rare
  • favorite explanation is a giant burst from a magnetar, a highly magnetized type of neutron star
  • performed approximately a year after the FRBs were first spotted, looked at whether the objects continued to produce emission, but the signals appear to be nonrepeating
  • Efforts are ongoing at the moment to detect FRBs in close to real time, such that they can be followed up quickly
Mars Base

At last, Voyager 1 slips into interstellar space | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/..._slips_into_interstellar_space

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  • the probe is surrounded by a relatively dense fog of galactic particles rather than a thin mist of solar ones
  • from the beginning
  • team hoped the probes would survive long enough to investigate the region of space where our star’s dominance finally wanes
  • ...14 more annotations...
  • more than 60,000 kilometers per hour
  • August 25, when solar particles disappeared for good
  • combined with a surge in higher-energy particles from other stars, suggested that Voyager had exited the heliosphere
  • Several well-publicized studies made that claim
  • colleagues resisted that conclusion
  • lacked evidence of what they thought would be the key signature of interstellar space: a shift in the direction of the magnetic field
  • Solar plasma produces a distinctive magnetic field because it all comes from the same source
  • scientists expected that the field would shift in interstellar space, where particles flit around in all directions
  • Not everyone agrees, including a few holdouts on the Voyager team
  • have written a paper demonstrating how plasma could become dense enough within the heliosphere to produce
  • measurement
  • many other astrophysicists say the evidence is overwhelming that Voyager 1 has crossed the heliopause, but they acknowledge that they have to determine why the magnetic field direction didn’t shift
  • NASA estimates that Voyager 1 has enough plutonium fuel to keep all its instruments powered for another seven years
  • August 25, 2012 — the same date, coincidentally, that the world lost its most famous human space explorer, Neil Armstrong
Mars Base

Move Over, Gravity: Black Hole Magnetic Fields May Have Powerful Pull - 0 views

www.universetoday.com/...-fields-may-have-powerful-pull

scibyte134 BlackHole

shared by Mars Base on 05 Jun 14 - No Cached
  • It’s oft-repeated that black holes are powerful gravity wells, because they represent a dense concentration of matter in one location
  • magnetic fields
  • A new study suggests that
  • ...1 more annotation...
  • could be at least as strong as gravity in supermassive black holes, the singularities that lurk in the center of many galaxies
Mars Base

Researchers debunk the IQ myth - 0 views

medicalxpress.com/...2012-12-debunk-iq-myth.html

scibyte76 IQ

shared by Mars Base on 23 Dec 12 - No Cached
  • After conducting the largest online intelligence study on record
  • research team has concluded that the notion of measuring one's intelligence quotient or IQ by a singular, standardized test is highly misleading
  • study, which included more than 100,000 participants
  • ...8 more annotations...
  • Utilizing an online study open to anyone, anywhere in the world, the researchers asked respondents to complete 12 cognitive tests tapping memory, reasoning, attention and planning abilities, as well as a survey about their background and lifestyle habits.
  • expected a few hundred responses, but thousands and thousands of people took part, including people of all ages, cultures and creeds from every corner of the world
  • The results showed that when a wide range of cognitive abilities are explored, the observed variations in performance can only be explained with at least three distinct components: short-term memory, reasoning and a verbal component
  • No one component, or IQ, explained everything
  • scientists used a brain scanning technique known as functional magnetic resonance imaging (fMRI), to show that these differences in cognitive ability map onto distinct circuits in the brain.
  • Intriguingly, people who regularly played computer games did perform significantly better in terms of both reasoning and short-term memory
  • smokers performed poorly on the short-term memory and the verbal factors
  • people who frequently suffer from anxiety performed badly on the short-term memory factor in particular
Mars Base

IBM researchers make world's smallest movie using atoms (w/ video) - 0 views

phys.org/...orld-smallest-movie-atoms.html

scibyte92 scibyte93

shared by Mars Base on 02 May 13 - No Cached
  • Scientists from IBM
  • unveiled the world's smallest movie, made with one of the tiniest elements in the universe: atoms
  • Named "A Boy and His Atom," the Guinness World Records -verified movie used thousands of precisely placed atoms to create nearly 250 frames of stop-motion action.
  • ...11 more annotations...
  • This movie is a fun way to share the atomic-scale world while opening up a dialogue with students and others on the new frontiers of math and science
  • In order to make the movie, the atoms were moved with an IBM-invented scanning tunneling microscope
  • weighs two tons, operates at a temperature of negative 268 degrees Celsius and magnifies the atomic surface over 100 million times
  • IBM Research lab one of the few places in the world where atoms can be moved with such precision.
  • Remotely operated on a standard computer, IBM researchers used the microscope to control a super-sharp needle along a copper surface to "feel" atoms
  • Only 1 nanometer away from the surface, which is a billionth of a meter in distance, the needle can physically attract atoms and molecules on the surface and thus pull them to a precisely specified location on the surface
  • moving atom makes a unique sound that is critical feedback in determining how many positions it's actually moved
  • scientists rendered still images of the individually arranged atoms, resulting in 242 single frames
  • the same team of IBM researchers who made this movie also recently created the world's smallest magnetic bit. They were the first to answer the question of how many atoms it takes to reliably store one bit of magnetic information: 12.
  • it takes roughly 1 million atoms to store a bit of data on a modern computer or electronic device
  • atomic memory could one day store all of the movies ever made in a device the size of a fingernail.
Mars Base

End of the World: 10 Disasters That Could End It All At Any Given Second - Best of the ... - 0 views

botw.org/endworld.html

scibyte75 End-of-the-World

shared by Mars Base on 13 Dec 12 - Cached
  • Gamma-Ray Burst
  • Gamma-ray bursts are extremely powerful, estimated to have 10 quadrillion times more energy than our sun
  • They are created by the collision of two collapsed stars
  • ...17 more annotations...
  • it is almost impossible to visualize collapsed stars making it even more difficult to predict the location of a gamma-ray burst
  • A burst 1,000 light years from the earth (further away than most of our stars) would create an explosion as bright as our sun and bring a hasty destruction to earth
  • atmosphere and the ozone would provide protection at first it would soon be cooked away by the radiation. UV rays would kill the photosynthetic plankton in the ocean, which provide most of the earth's oxygen
  • At least one burst can be seen each day when watching our sky with gamma-ray vision; it can't be too long before there is one closer to home
  • earth's atmosphere and magnetic field protect us from the consequences of these potentially lethal flares
  • The sun emits solar flares, also known as coronal mass ejections, towards earth frequently
  • These flares are large magnetic outbursts which contain high-speed subatomic particles
  • evidence has been found that sun-like stars far from our solar system can briefly increase in brightness by 20 times
  • hypothesized that these increases are caused by super-flares, which are millions of times more powerful than the common solar flare
  • If our sun were to emit one of these super-flares it would literally fry the earth
  • if our sun's activity were to decrease by a mere 1% (which has been known to happen to many sun-like stars) we would be flung back into another ice age
  • Solar Activity (Super-Flares and Decreased Activity)
  • Particle Accelerators
  • When electric fields are used to accelerate protons they could collide at speed fast enough to create black holes or bits of altered matter
  • These small black holes would slowly engulf our planet
  • pieces of altered matter, called strangeletes, would destroy any ordinary matter they came in contact with, eventually annihilating the entire planet
  • most scientists assure that none of the particle accelerators being used at the present are strong enough to bring about these events
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