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Mars Base

Numbers Games Devised to Aid People with "Dyscalculia": Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte78 Dyscalculia

shared by Mars Base on 19 Jan 13 - No Cached
  • The study confirmed for Butterworth that developmental forms of dyscalculia are the result of basic problems in comprehending numbers and not in other cognitive faculties
  • determining exactly what those problems are would prove challenging
  • approximate number sense, distinguishes larger quantities from smaller ones, be they dots flashing on a screen or fruits in a tree.
  • ...13 more annotations...
  • A second ancient number system allows humans and many other animals to instantly and precisely recognize small quantities, up to four.
  • People who are poor at distinguishing approximate quantities do badly in maths, suggesting that the approximate-number system is crucial.
  • some work shows that dyscalculics are poor at recognizing small numbers, suggesting that this ability is also fundamental to numeracy
  • scans of people with dyscalculia suggest that their intraparietal sulci are less active when processing numbers and less connected with the rest of the brain compared with numerate children and adults.
  • views such results as consequences, not causes, of the poor numerical abilities that characterize dyscalculia.
  • argues that another cognitive capacity is even more fundamental to number sense
  • calls this 'numerosity coding': the understanding that things have a precise quantity associated with them, and that adding or taking things away alters that quantity.
  • Approximation and a sense of small numbers, while critical, are not enough for humans to precisely grasp large numbers,
  • Language, he argues, empowers humans to integrate the two number systems — giving them the ability to intuitively distinguish, say, 11,437 from 11,436.
  • young children who could not yet count past two nonetheless understood that adding pennies to a bowl containing six somehow altered its number, even if the children couldn't say exactly how.
  • If numerosity coding is fundamental, it predicts that dyscalculics
  • struggle to enumerate and manipulate all numbers, large and small.
  • hopes that, by honing this ability, the Number Sense games will help support his research ideas
Mars Base

Space Exploration By Robot Swarm - 0 views

www.universetoday.com/...ace-exploration-by-robot-swarm

scibyte47 robot space exploration AsteroidMining

shared by Mars Base on 16 May 12 - No Cached
  • one researcher from Stanford University is suggesting we unleash a swarm of rover/spacecraft hybrids that can explore en masse.
  • been developing a concept under NASA’s Innovative Advanced Concepts (NIAC) Program that would see small spherical robots deployed to small worlds, such as Mars’ moons Phobos and Deimos, where they would take advantage of low gravity to explore — literally —  in leaps and bounds.
  • similar to what NASA has done in the past with the Mars rovers, except multiplied in the number of spacecraft (and reduced in cost.)
  • ...5 more annotations...
  • were one spacecraft to fail the entire mission wouldn’t be compromised
  • robots would be deployed from a “mother” spacecraft and spring into action upon landing, tumbling
  • hybrid rovers could also help prepare for future, more in-depth exploration.
  • exploration of small bodies would help unravel the origin of the solar system and its early evolution
  • evaluate the resource potential of small bodies in view of future human missions beyond Earth.”
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

Smallest Exoplanet Yet Discovered by 'Listening' to a Sun-like Star - 0 views

www.universetoday.com/...y-listening-to-a-sun-like-star

scibyte83 exoplanet

shared by Mars Base on 21 Feb 13 - No Cached
  • 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
  • ...24 more annotations...
  • 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
Mars Base

Nanotechnology breakthrough could dramatically improve medical tests - 0 views

phys.org/...logy-breakthrough-medical.html

scibyte49 NanoDevice MedicalTreatment

shared by Mars Base on 01 Jun 12 - No Cached
  • The material consists of a series of glass pillars in a layer of gold. Each pillar is speckled on its sides with gold dots and capped with a gold disk. Each pillar is just 60 nanometers in diameter, 1/1,000th the width of a human hair
  • laboratory test used to detect disease and perform biological research could be made more than 3 million times more sensitive
  • increased performance could greatly improve the early detection of cancer, Alzheimer's disease and other disorders by allowing doctors to detect far lower concentrations of telltale markers than was previously practical.
  • ...20 more annotations...
  • The greater the glow, the more of the biomarker is present.
  • if the amount of biomarker is too small, the fluorescent light is too faint to be detected, setting the limit of detection
  • major goal in immunoassay research is to improve the detection limit.
  • involves a common biological test called an immunoassay, which mimics the action of the immune system to detect the presence of biomarkers
  • When biomarkers are present
  • the immunoassay test produces a fluorescent glow (light) that can be measured in a laboratory
  • tackled this limitation by using nanotechnology to greatly amplify the faint fluorescence from a sample
  • fashioning glass and gold structures so small they could only be seen with a powerful electron microscope
  • able to drastically increase the fluorescence signal compared to conventional immunoassays, leading to a 3-million-fold improvement in the limit of detection
  • key to the breakthrough lies in a new artificial nanomaterial called D2PA
  • a thin layer of gold nanostructures surrounded glass pillars just 60 nanometers in diameter.
  • A nanometer is one billionth of a meter; that means about 1,000 of the pillars laid side by side would be as wide as a human hair.
  • e pillars are spaced 200 nanometers apart and capped with a disk of gold on each pillar
  • sides of each pillar are speckled with even tinier gold dots about 10 to 15 nanometers in diameter
  • a sample such as blood, saliva or urine is taken from a patient and added to small glass vials containing antibodies that are designed to "capture" or bind to biomarkers of interest in the sample
  • Another set of antibodies that have been labeled with a fluorescent molecule are then added to the mix
  • biomarkers are not present in the vials
  • fluorescent detection antibodies do not attach to anything and are washed away
  • immunoassays are commonly used in drug discovery and other biological research.
  • plays a significant role in other areas of chemistry and engineering, from light-emitting displays to solar energy harvesting
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

Santorini Bulges as Magma Balloons Underneath - 0 views

news.nationalgeographic.com/...lava-santorini-volcano-science

scibyte63 Santorini

shared by Mars Base on 13 Sep 12 - No Cached
  • Santorini locals began to suspect last year that something was afoot with the volcano under their Greek island group
  • Wine glasses occasionally vibrated and clinked in cafes, suggesting tiny tremors, and tour guides smelled strange gasses.
  • satellite radar technology has revealed the source of the symptoms. A rush of molten rock swelled the magma chamber under the volcano by some 13 to 26 million cubic yards (10 to 20 million cubic meters)—about 15 times the volume of London's Olympic Stadium—between January 2011 and April 2012
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  • even forced parts of the island's surface to rise upward and outward by 3 to 5.5 inches (8 to 14 centimeters).
  • volcano has been quiet for 60 years
  • recent events don't indicate an imminent eruption
  • the earthquake activity and the rate of bulging have both slowed right down in the last few months, it doesn't look as though the volcano is about to start to erupt, and it is quite likely that it could remain quiet for another few years or decades.
  • don't know enough about the lifecycle of large volcanoes in between eruptions to be certain
  • beginning in the January 2011 data, more than a thousand small quakes, most of them imperceptible
  • confirmed a subtle rise in Santorini's surface level with satellite radar images and GPS receivers
  • Catastrophic eruptions on Santorini, which produce mostly pumice rather than lava, appear to occur here about 20,000 years apart
  • The last one, in 1950, oozed enough lava to cover a few tennis courts
  • Despite its relative quiet, Santorini is an ideal location to learn more about processes like the magma chamber's rapid inflation
  • While satellite evidence of swelling magma chambers has rarely been available for an active volcano, the processes the data represent may not be all that unusual
  • some large volcanoes like Santorini and Yellowstone spend hundreds or thousands of years in a state of what you'd call dormancy
  • they'll often have these little restless patches
  • These types of phenomena are likely to be common, but you need the right instruments and technology to detect what are usually rather small changes in behavior."
  • we aren't any closer to knowing if, or when, the next lava eruption might happen
  • likening the recent swelling to someone blowing a big breath into an invisible balloon.
  • don't know how small or big the balloon is, and we don't know whether just one more breath will be enough for it to pop or not
Mars Base

Spitzer Finds Possible Exoplanet Smaller than Earth - NASA Spitzer Space Telescope - 0 views

www.spitzer.caltech.edu/...e-Exoplanet-Smaller-than-Earth

scibyte55 exoplanet

shared by Mars Base on 18 Jul 12 - No Cached
  • Astronomers using NASA's Spitzer Space Telescope have detected what they believe is a planet two-thirds the size of Earth. The exoplanet candidate, called UCF-1.01, is located a mere 33 light-years away, making it possibly the nearest world to our solar system that is smaller than our home planet. 
  • strong evidence for a very small, very hot and very near planet
  • new-planet candidate was found unexpectedly
  • ...16 more annotations...
  • studying the Neptune-sized exoplanet GJ 436b, already known to exist around the red-dwarf star GJ 436
  • In the Spitzer data, the astronomers noticed slight dips in the amount of infrared light streaming from the star, separate from the dips caused by GJ 436b
  • review of Spitzer archival data showed the dips were periodic, suggesting a second planet might be orbiting the star and blocking out a small fraction of the star's light. 
  • diameter would be approximately 5,200 miles (8,400 kilometers), or two-thirds that of Earth
  • revolve
  • about seven times the distance of Earth from the moon, with its "year" lasting only 1.4 Earth days
  • the exoplanet's surface temperature would be more than 1,000 degrees Fahrenheit (almost 600 degrees Celsius
  • might therefore resemble a cratered, mostly geologically dead world like Mercury
  • another possibility; that the extreme heat of orbiting so close to GJ 436 has melted the exoplanet's surface
  • colleagues noticed hints of a third planet
  • Spitzer has observed evidence of the two new planets several times each
  • even the most sensitive instruments are unable to measure exoplanet masses as small
  • mass is required for confirming a discovery
  • cautiously calling both bodies exoplanet candidates for now.
  • 1,800 stars identified by NASA' Kepler space telescope as candidates for having planetary systems, just three are verified to contain sub-Earth-sized exoplanets
  • only one exoplanet is thought to be smaller than the Spitzer candidates
Mars Base

'Predictive policing' takes byte out of crime - 0 views

phys.org/...12-07-policing-byte-crime.html

GrabBag PredictingCrime

shared by Mars Base on 29 Jul 12 - No Cached
  • Without some of the sci-fi gimmickry, police departments from Santa Cruz, California, to Memphis, Tennessee, and law enforcement agencies from Poland to Britain have adopted these new techniques
  • criminals follow patterns, and with software -- the same kind that retailers like Wal-Mart and Amazon use to determine consumer purchasing trends -- police can determine where the next crime will occur and sometimes prevent it.
  • criminal behavior was not that different from examining other types of behavior like shopping
  • ...29 more annotations...
  • People are creatures of habit
  • could help in cities where tight budgets were forcing patrol reductions.
  • The key to success in predictive policing is getting as much data as possible to determine patterns. This can be especially useful in property crimes like auto theft and burglary, where patterns can be detected
  • factors in attributes like the time of year, whether it is hot and humid or cold and snowy, if it is a payday when people are carrying a lot of cash
  • not saying a crime will occur at a particular time and place
  • can expect a wave of vehicle thefts based one everything we know
  • officials said serious crimes fell 30 percent and violent crimes declined 15 percent since implementing predictive analytics
  • in 2006
  • CRUSH -- Criminal Reduction Utilizing Statistical History
  • targeted certain "hot spots" to allow police to deploy more efficiently
  • "If the data is indicating a hot spot, we are able to immediately deploy resources there
  • beat officers can use their instincts for similar results
  • software could be far more precise, such as predicting burglaries in a small geographic area between 10 pm and 2 am.
  • the software was able to help police break up a group that was committing armed robberies
  • 84 robberies, but we had no idea it was so organized
  • crunching the numbers, police were able to pinpoint the zone and time of likely holdups
  • police officials from as far away as Hong Kong, Rio de Janeiro and Estonia have come to review the experience in Memphis
  • In Los Angeles, another program
  • was tested in a single precinct, and resulted in a 12 percent drop in crime while the rest of the city saw a 0.2 percent increase
  • led to the creation of a company called PredPol
  • based on a model from mathematician
  • science that underlies the tool will work anywhere. The question is does the agency maintain a database
  • While
  • helping "smarter" policing, it does raise concerns about Big Brother-like snooping
  • technology could be positive but that it could lower the threshold for constitutional protections on "unreasonable" searches.
  • IBM's Cleverly said the technology can in many cases improve privacy
  • How do you cross-examine a computer
  • If the search is based on a computer algorithm
  • how will this affect reasonable suspicion
  • Mars Base on 29 Jul 12
     
    nd in a lot of instances we are able to make quality arrests because we're in the right area at the right time," he told AFP. Although beat officers can use their instincts for similar results, Williams said the software could be far more precise, such as predicting burglaries in a small geographic area between 10 pm and 2 am. In one case, the software was able to help police break up a group that was committing armed robbe
Mars Base

New energy source for future medical implants: sugar - 0 views

phys.org/...e-future-medical-implants.html

scibyte51 medical FuelCell

shared by Mars Base on 13 Jun 12 - No Cached
  • This silicon wafer consists of glucose fuel cells of varying sizes; the largest is 64 by 64 mm
  • MIT engineers have developed a fuel cell that runs on the same sugar that powers human cells: glucose
  • This glucose fuel cell could be used to drive highly efficient brain implants of the future, which could help paralyzed patients move their arms and legs again
  • ...22 more annotations...
  • strips electrons from glucose molecules to create a small electric current
  • The idea of a glucose fuel cell is not new
  • In the 1970s, scientists showed they could power a pacemaker with a glucose fuel cell, but the idea was abandoned in favor of lithium-ion batteries, which could provide significantly more power per unit area than glucose fuel cells
  • glucose fuel cells also utilized enzymes that proved to be impractical for long-term implantation in the body, since they eventually ceased to function efficiently
  • The new twist
  • is that it is fabricated from silicon, using the same technology used to make semiconductor electronic chips
  • has no biological components
  • consists of a platinum catalyst that strips electrons from glucose
  • mimicking the activity of cellular enzymes that break down glucose to generate ATP
  • So far, the fuel cell can generate up to hundreds of microwatts — enough to power an ultra-low-power and clinically useful neural implant.
  • in theory, the glucose fuel cell could get all the sugar it needs from the cerebrospinal fluid (CSF) that bathes the brain and protects it from banging into the skull
  • are very few cells in the CSF
  • There is also significant glucose in the CSF, which does not generally get used by the body
  • only a small fraction of the available power is utilized by the glucose fuel cell, the impact on the brain’s function would likely be small.
  • the work is a good step toward developing implantable medical devices that don’t require external power sources.
  • ultra-low-power electronics, having pioneered such designs for cochlear implants and brain implants
  • combined with such ultra-low-power electronics, can enable brain implants or other implants to be completely self-powered
  • group has worked on all aspects of implantable brain-machine interfaces and neural prosthetics, including recording from nerves, stimulating nerves
  • decoding nerve signals and communicating wirelessly with implants
  • designed to record electrical activity from hundreds of neurons in the brain’s motor cortex, which is responsible for controlling movement
  • data is amplified and converted into a digital signal so that computers
  • can analyze it and determine which patterns of brain activity produce movement
Mars Base

Two 'Weird' Alien Planets Found Around Bright, Distant Stars | Space.com - 1 views

www.space.com/ets-kelt-telescope-aas220.html

scibyte52 exoplanets

shared by Mars Base on 19 Jun 12 - No Cached
  • Astronomers using a small ground-based telescope have discovered two unusual alien planets around extremely bright, distant stars.
  • detected using the Kilodegree Extremely Little Telescope (KELT) in southern Arizona, which has a lens that is roughly as powerful as a high-end digital camera
  • slightly more diminutive than Kepler
  • ...20 more annotations...
  • KELT-1b, is a massive world that is both incredibly hot and dense. The alien planet, which is mostly metallic hydrogen, is slightly larger than Jupiter, but contains a whopping 27 times the mass
  • completes one orbit in a mere 29 hours
  • surface temperature is likely above 4,000 degrees Fahrenheit (roughly 2,200 degrees Celsius
  • receiving 6,000 times the amount of radiation that Earth receives from the sun
  • located approximately 825 light-years away in the constellation of Andromeda
  • massive enough that KELT-1 has raised tides on its parent star and actually spun it
  • both KELT-1 and its parent star are locked in each other's gaze as they go around."
  • KELT-2Ab, and is located about 360 light-years away in the constellation of Auriga
  • 30 percent larger than Jupiter with 50 percent more mass.
  • KELT-2Ab's parent star is so bright it can be seen from Earth through binoculars
  • the star is so luminous that researchers will be able to make direct observations of the planet's atmosphere by examining light that shines through it when the star passes within KELT North's field of view again in November.
  • Follow-up observations are also being planned
  • as well as several space observatories, including the Hubble Space Telescope and the infrared Spitzer Space Telescope.
  • orbits a star that is slightly bigger than the sun, within a binary system
  • one star is slightly bigger than our sun, and the other star is slightly smaller. KELT-2Ab orbits the bigger star, which is bright enough to be seen from Earth with binoculars
  • using the so-called transit method, which involves watching for tiny dips in the star's light that could indicate a planet is crossing, or transiting
  • Rather than staring at a small group of stars at high resolution, the twin KELT North and KELT South telescopes observe millions of very bright stars at low resolution,
  • KELT North scans the northern sky from Arizona
  • KELT South covers the southern sky from Cape Town, South Africa.
  • small ground-based KELT telescopes provide a low-cost alternative for exoplanet hunters by primarily using off-the-shelf technology. The hardware for a KELT telescope costs less than $75,000
Mars Base

Water on the Moon in Pictures | Lunar Ice | Space.com - 0 views

www.space.com/on-water-lunar-ice-photos.html

LunarWater

shared by Mars Base on 21 Jun 12 - No Cached
  • In July 2008, water was found conclusively for the first time inside ancient moon samples brought back by Apollo astronauts
  • gathered by the Apollo 15 mission
  • new analytic technique to detect water
  • ...20 more annotations...
  • strongly suggests that water has been a part of the Moon since its early existence – and perhaps since it was first created
  • 2009 discovery of water on the moon
  • images show a very young lunar crater on the side of the moon that faces away from Earth
  • NASA's Moon Mineralogy Mapper on the Indian Space Research Organization's Chandrayaan-1 spacecraft
  • distribution of water-rich minerals (light blue) is shown around a small crater
  • 2009, observations from three spacecraft showed signals of water across moon's surface
  • stream of charged hydrogen ions carried from the sun to the moon by the solar wind
  • might explain the possible presence of hydroxyl or water on the moon.
  • NASA's Mini-SAR instrument, which flew aboard India's Chandrayaan-1 spacecraft, found more than 40 small craters with water ice. The craters range in size from 1 to 9 miles (2 to 15 km) in diameter. Although the total amount of ice depends on its thickness in each crater, it's estimated there could be at least 600 million metric tons of water ice. The red circles denote fresh craters; the green circle mark anomalous craters.
  • NASA's Mini-SAR instrument
  • aboard India's Chandrayaan-1 spacecraft
  • found more than 40 small craters with water ice
  • total amount of ice depends on its thickness in each crater
  • estimated there could be at least 600 million metric tons of water ice
  • the moon's permanently shadowed regions may hide stores of water
  • photo of the moon's south pole
  • January 2011 study suggested that water on the moon most likely came from comets that pelted the lunar surface after its formation
  • In October 2010, scientists reported that a frigid crater called Cabeus at the moon's south pole is jam-packed with water ice, with some spots wetter than Earth's Sahara desert
  • NASA's LCROSS probe discovered beds of water ice at the lunar south pole when it impacted the moon in October 2009. This visible camera image shows the ejecta plume at about 20 seconds after LCROSS's impact on the moon.
  • Recent studies have found vast amounts of water ice at or near the lunar surface. But the inside of the moon is bone dry, an August 2010 study found.
Mars Base

The Moon Is 100 Million Years Younger Than Thought | Space.com - 0 views

www.space.com/100-million-years-younger.html

scibyte104 moon

shared by Mars Base on 24 Sep 13 - No Cached
  • new research suggests.
  • The moon is
  • younger than scientists had previously believed
  • ...23 more annotations...
  • leading theory of how the moon formed 
  • it was created when a mysterious planet — one the size of Mars or larger — slammed into Earth
  • about 4.56 billion years ago, just after the solar system came together
  • new analyses of lunar rocks suggest that the moon, which likely coalesced from the debris blasted into space by this monster impact, is actually between 4.4 billion and 4.45 billion years old
  • make the moon 100 million years younger than previously thought, could reshape scientists' understanding of the early Earth
  • several important implications of this late moon formation that have not yet been worked out
  • , if the Earth was already differentiated prior to the giant impact, would the impact have blown off the primordial atmosphere that formed from this earlier epoch of Earth history
  • Scientists know the solar system's age (4.568 billion years) quite well
  • they can pin down the formation times of relatively small bodies such as asteroids precisely
  • by noting when these objects underwent extensive melting
  • a consequence,
  • of the heat generated by the collision and fusion of these objects' building-block "planetesimals."
  • analysis of meteorites that came from the asteroid Vesta and eventually rained down on Earth reveals that the 330-mile-wide (530 kilometers) space rock is 4.565 billion years old
  • Vesta cooled relatively quickly and is too small to have retained enough internal heat to drive further melting or volcanism
  • tougher to nail down the age of larger solar-system bodies
  • Earth likely took longer to grow to full size compared to a small asteroid like Vesta
  • every step in its growth tends to erase, or at least cloud, the memory of earlier events
  • Scientists keep getting better and better estimates
  • as they refine their techniques and technology improves. And those estimates are pushing the moon's formation date farther forward in time.
  • The moon is thought to have harbored a global ocean of molten rock shortly after its dramatic formation
  • Currently, the most precisely determined age for the lunar rocks that arose from that ocean is 4.360 billion years
  • here on Earth, scientists have found signs in several locations of a major melting event that occurred around 4.45 billion years ago
  • evidence is building that the catastrophic collision that formed the moon and reshaped Earth occurred around that time, rather than 100 million years or so before
Mars Base

ScienceShot: Small World Spotted Far Beyond Pluto | Science/AAAS | News - 0 views

news.sciencemag.org/...world-spotted-far-beyond-pluto

scibyte125 Planet

shared by Mars Base on 27 Mar 14 - No Cached
  • The object journeys 80 to 452 AU from the sun, never approaching Neptune (30 AU) or Pluto (39.5 AU).
  • The new world is roughly 450 kilometers across, just one-fifth Pluto's diameter
  • If Pluto were as big as a basketball, Sedna would be a softball and the new world a mere golf ball
  • ...2 more annotations...
  • Pluto orbits the sun every 248 years, the new world requires 4340 years and Sedna 12,600 years to do the same
  • Both Sedna and its small sidekick probably belong to the inner part of the Oort cloud,
Mars Base

Dazzling Meteor Fireball Lights Up UK Night Sky | Space.com - 0 views

www.space.com/ball-video-united-kingdom.html

scibyte64 meteorite

shared by Mars Base on 25 Sep 12 - No Cached
  • A spectacular meteor wowed stargazers across the United Kingdom Friday (Sept. 21) when it flared up and shattered into piece
  • spotted by observers across Scotland and northern England as well as Ireland
  • Many observers captured views of the meteor on camera
  • ...9 more annotations...
  • video of the Sept. 21 meteor shows what appears to be a fireball created as a small space rock breaks apart in Earth's atmosphere. Pieces of the meteor can easily be seen separating from the main body in his view
  • many witnesses to wonder if it was sparked by a man-made piece of space junk falling out of orbit
  • experts have conclusively tied the event to a naturally occurring space rock burning up in Earth's atmosphere
  • Veteran satellite tracker Marco Langbroe
  • the fireball was definitely a meteor.
  • sighting reports to determine the fireball's trajectory and studied videos posted by witnesses to determine how long it lasted
  • ack-of-the-envelope reconstruction therefore shows that this must have been a meteoric fireball, quite likely of asteroidal origin, and we definitely can exclude a satellite re-entry
  • meteor in space is called a meteoroid. Only when it flares up in the night sky does it become a meteor. Any remains of the object that reach the ground, meanwhile, are called meteorites
  • Earlier this year, a rare daytime fireball surprised U.S. observers in California and Nevada when it unleashed a sonic boom that some mistook for a small earthquake. The meteor was caused by a minivan-size asteroid and created several meteorites that NASA retrieved in a follow-up search
Mars Base

Heart repair breakthroughs replace surgeon's knife - 0 views

medicalxpress.com/...eakthroughs-surgeon-knife.html

scibyte87 scibyte88 heart

shared by Mars Base on 25 Mar 13 - No Cached
  • Many problems that once required sawing through the breastbone and opening up the chest for open heart surgery now can be treated
  • through a tube
  • These minimal procedures used to be done just to unclog arteries and correct less common heart rhythm problems
  • ...42 more annotations...
  • Now some patients are getting such repairs for valves, irregular heartbeats, holes in the heart and other defects—without major surgery
  • Doctors even are testing ways to treat high blood pressure with some of these new approaches
  • Instead of opening the chest, we're able to put catheters in through the leg, sometimes through the arm
  • Many patients after having this kind of procedure in a day or two can go home
  • It may lead to cheaper treatment, although the initial cost of the novel devices often offsets the savings from shorter hospital stays
  • Not everyone can have catheter treatment, and some promising devices have hit snags in testing
  • Others on the market now are so new that it will take several years to see if their results last as long as the benefits from surgery do.
  • these procedures have allowed many people too old or frail for an operation to get help for problems that otherwise would likely kill them
  • You can do these on 90-year-old patients
  • also offer an option for people who cannot tolerate long-term use of blood thinners or other drugs to manage their conditions
  • Heart valves
  • Millions of people have leaky heart valves. Each year, more than 100,000 people in the United States alone have surgery for them
  • Without a valve replacement operation, half of these patients die within two years, yet many are too weak to have one.
  • just over a year ago,
  • Edwards Lifesciences Corp. won approval to sell an artificial aortic valve flexible and small enough to fit into a catheter and be wedged inside the bad one
  • At first it was just for inoperable patients. Last fall, use was expanded to include people able to have surgery but at high risk of complications.
  • Catheter-based treatments for other valves also are in testing. One for the mitral valve
  • mixed review by federal Food and Drug Administration advisers this week; whether it will win FDA approval is unclear. It is already sold in Europe
  • Heart rhythm problems
  • Catheters can contain tools to vaporize or "ablate" bits of heart tissue that cause abnormal signals that control the heartbeat
  • Now catheter ablation is being used for the most common rhythm problem—atrial fibrillation, which plagues about 3 million Americans and 15 million people worldwide.
  • Ablation addresses the underlying rhythm problem. To address the stroke risk from pooled blood, several novel devices aim to plug or seal off the pouch
  • The upper chambers of the heart quiver or beat too fast or too slow. That lets blood pool in a small pouch off one of these chambers
  • Clots can form in the pouch and travel to the brain, causing a stroke
  • a tiny lasso to cinch the pouch shut. It uses two catheters that act like chopsticks. One goes through a blood vessel and into the pouch to help guide placement of the device, which is contained in a second catheter poked under the ribs to the outside of the heart. A loop is released to circle the top of the pouch where it meets the heart, sealing off the pouch.
  • A different kind of device
  • sold in Europe and parts of Asia, but is pending before the FDA in the U.S
  • like a tiny umbrella pushed through a vein and then opened inside the heart to plug the troublesome pouch.
  • Early results from a pivotal study released by the company suggested it would miss a key goal, making its future in the U.S. uncertain.
  • Heart defects
  • St. Jude Medical Inc.'s Amplatzer is a fabric-mesh patch threaded through catheters to plug the hole
  • In two new studies, the device did not meet the main goal of lowering the risk of repeat strokes in people who had already suffered one, but some doctors were encouraged by other results
  • Сlogged arteries
  • The original catheter-based treatment—balloon angioplasty—is still used hundreds of thousands of times each year in the U.S. alone
  • A Japanese company, Terumo Corp., is one of the leaders of a new way to do it that is easier on patients—through a catheter in the arm rather than the groin
  • Newer stents that prop arteries open and then dissolve over time, aimed at reducing the risk of blood clots, also are in late-stage testing
  • High blood pressure
  • About
  • 1 billion people worldwide have high blood pressure, a major risk factor for heart attacks
  • Researchers are testing a possible long-term fix for dangerously high pressure that can't be controlled with multiple medications.
  • uses a catheter and radio waves to zap nerves, located near the kidneys, which fuel high blood pressure
  • At least one device is approved in Europe and several companies are testing devices in the United States
Mars Base

Should This Alien World Even Exist? This Young Disk Could Challenge Planet-Formation Th... - 0 views

www.universetoday.com/...enge-planet-formation-theories

scibyte98 exoplanet

shared by Mars Base on 14 Jun 13 - No Cached
  • gap in the cloud? That could be a planet being born some 176 light-years away from Earth
  • small planet, only 6 to 28 times Earth’s mass.
  • This alien world, if we can confirm it, shouldn’t be there according to conventional planet-forming theory
  • ...20 more annotations...
  • The gap in the image above — taken by the Hubble Space Telescope — probably arose when a planet under construction swept through the dust and debris in its orbit
  • That’s not much of a surprise (at first blush) given what we think we know about planet formation
  • You start with a cloud of debris and gas swirling around a star, then gradually the bits and pieces start colliding, sticking together and growing bigger into small rocks, bigger ones and eventually, planets or gas giant planet cores
  • this planet is a heck of a long way from its star, TW Hydrae, about twice Pluto’s distance from the sun
  • Given that alien systems’ age, that world shouldn’t have formed so quickly.
  • Astronomers believe that Jupiter took about 10 million years to form at its distance away from the sun
  • This planet near TW Hydrae should take 200 times longer to form because the alien world is moving slower, and has less debris to pick up
  • because TW Hydrae‘s system is believed to be only 8 million years old.
  • TW Hydrae is only 55 percent as massive as our sun
  • astronomers are seriously investigating other theories
  • One alternative brought up in the press release: perhaps part of the disc collapsed due to gravitational instability
  • If that is the case, a planet could come to be in only a few thousand years, instead of several million
  • add to planet formation theories as to how you can actually form a planet very far out
  • If we can actually confirm that there’s a planet there, we can connect its characteristics to measurements of the gap properties
  • direct collapse” theory, though: astronomers believe it takes a bunch of matter that is one to two times more massive than Jupiter before a collapse can occur to form a planet
  • this world is no more than 28 times the mass of Earth, as best as we can figure
  • Jupiter itself is 318 times more massive than Earth
  • There are also intriguing results about the gap
  • dust grains in this system, orbiting nearby the gap, are still smaller than the size of a grain of sand
  • Astronomers plan to use ALMA and the James Webb Space Telescope, which should launch in 2018, to get a better look
Mars Base

Kepler Team Finds System with Two Potentially Habitable Planets - 0 views

www.universetoday.com/...-potentially-habitable-planets

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • scientists analyzing data from NASA’s Kepler mission has found a planetary system with two small, potentially rocky planets that lie within the habitable zone of their star
  • Kepler-62, is a bit smaller and cooler than our Sun, and is home to a five-planet system
  • Two of the worlds, Kepler-62e and Kepler-62f are the smallest exoplanets yet found in a habitable zone, and they might both be covered in water or ice, depending on what kind of atmosphere they might have
  • ...19 more annotations...
  • The curves show the mass-radius-relation (average density) for different types of planets
  • The blue line indicates
  • planets made mostly (75%) of water, the black line that of planets like our Earth that consist almost exclusively of rock (
  • estimate of their mass places them in a region (blue areas) where it is highly probable for them to be earth-like planets, that is: planets with a solid (if possibly covered in water) surface
  • the empirical habitable zone, liquid water can exist on the surface of a planet if that planet has sufficient cloud cover. In the narrow habitable zone, liquid water can exist on the surface even without the presence of a cloud cover
  • while the sizes of Kepler 62e and 62f are known, their mass and densities are not.
  • every planet found in their size range so far has been rocky, like Earth
  • Life on these worlds would be under water with no easy access to metals, to electricity, or fire for metallurgy
  • life’s inventiveness to get to a technology stage will surprise us
  • Kepler-62e would have a bit more clouds than Earth according to computer models
  • More distant Kepler-62f would need the greenhouse effect from plenty of carbon dioxide to warm it enough to host an ocean
  • Kepler-62e probably has a very cloudy sky and is warm and humid all the way to the polar regions
  • Kepler-62f would be cooler, but still potentially life-friendly
  • the two would exhibit distinctly different colors and make our search for signatures of life easier on such planets in the near future
  • planets in the habitable zone were until now discovered by what is known as the radial velocity method
  • gives you a lower limit for the planet’s mass, but no information about its radius
  • What makes Kepler-62e and Kepler-62f so exciting is
  • We know their radius, which indicates that these are indeed rocky planets, and they orbit their star in the habitable zone
  • makes it difficult to assess whether or not a planet is rocky, like the Earth. A small radius (less than 2 Earth radii), on the other hand, is a strong indicator that a planet around is indeed rocky – unless we are talking about a planet around a very young star
Mars Base

Study unravels central mystery of Alzheimer's disease - 0 views

medicalxpress.com/...mystery-alzheimer-disease.html

scibyte90 Alzheimer

shared by Mars Base on 11 Apr 13 - No Cached
  • Until recently, Polleux's laboratory has been focused not on Alzheimer's research but on the normal development and growth of neurons
  • In 2011
  • reported that AMPK overactivation by metformin, among other compounds, in animal models impaired the ability of neurons to grow output stalks, or axons
  • ...25 more annotations...
  • Around the same time, separate research groups found clues that AMPK might also have a role in Alzheimer's disease
  • One group reported that AMPK can be activated in neurons by amyloid beta, which in turn can cause a modification of the protein tau in a process known as phosphorylation
  • a postdoctoral research associate
  • began by confirming that amyloid beta, in the small-aggregate ("oligomer") form that is toxic to synapses, does indeed strongly activate AMPK
  • amyloid beta oligomers stimulate certain neuronal receptors, which in turn causes an influx of calcium ions into the neurons
  • that this calcium influx triggers the activation of an enzyme called CAMKK2, which appears to be the main activator of AMPK in neurons
  • AMPK overactivation in neurons is the essential reason for amyloid beta's synapse-harming effect
  • neurons' dendritic spines—the rootlike, synapse-bearing input stalks that receive signals from other neurons
  • scientists showed that amyloid beta oligomers can't cause this dendritic spine loss unless AMPK overactivation occurs—and indeed AMPK overactivation on its own can cause the spine loss
  • the team used J20 mice, which are genetically engineered to overproduce mutant amyloid beta
  • when we blocked the activity of CAMKK2 or AMPK in these neurons, we completely prevented the spine loss
  • Recent studies have shown that amyloid beta's toxicity to dendritic spines depends largely on the presence of tau, but just how the two Alzheimer's proteins interact has been unclear
  • their colleagues are now following up with further experiments to determine what other toxic processes, such as excessive autophagy, are promoted by AMPK overactivation and might also contribute to the long-term aspects of Alzheimer's disease progression
  • also interested in the long-term effects of blocking AMPK overactivation in the J20 mouse model as well as in other mouse models of Alzheimer's disease, which normally develop cognitive deficits at later stages
  • the pharmaceuticals industry who are potentially interested in targeting either CAMKK2 or AMPK
  • show that brain damage in Alzheimer's disease is linked to the overactivation of an enzyme called AMPK
  • Researchers have known for years that people in the earliest stages of Alzheimer's disease begin to lose synapses in certain memory-related brain areas
  • findings, reported in the April
  • Small aggregates of the protein amyloid beta can cause this
  • but how they do so has been a mystery
  • Tangles of tau with multiple phosphorylations ("hyperphosphorylated" tau) are known to accumulate in neurons in affected brain areas in Alzheimer
  • investigate further, to determine whether the reported interactions of AMPK with amyloid beta and tau can in fact cause the damage seen in the brains of Alzheimer's patients
  • In addition
  • findings suggest the need for further safety studies on an existing drug, metformin.
  • , a popular treatment for Type 2 Diabetes, causes AMPK activation.
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