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Mars Base

ESA - ESA Spacecraft Operations - ESA station keeps contact with Russian Mars mission P... - 0 views

www.esa.int/...SEM5AJZW5VG_0.html

scibyte23 Phobos-Grunt

shared by Mars Base on 24 Nov 11 - No Cached
  • Following the first successful contact on Tuesday, ESA's tracking station in Australia again established two-way communication with Russia's Phobos–Grunt spacecraft on 23 November
  • data received from the spacecraft have been sent to the Russian mission control centre for analysis
  • The first pass was successful in that the spacecraft's radio downlink was commanded to switch on and telemetry was received
  • ...3 more annotations...
  • The signals received from Phobos–Grunt were much stronger than those initially received on 22 November, in part due to having better knowledge of the spacecraft's orbital position
  • Telemetry typically includes information on the status and health of a spacecraft's systems
  • 24 November
Mars Base

Russia 'makes first contact' with stranded Mars probe (Update) - 0 views

www.physorg.com/...ntact-stranded-mars-probe.html

Phobos-Grunt scibyte23

shared by Mars Base on 24 Nov 11 - No Cached
  • signal was received at a Russian station at the Baikonur cosmodrome in Kazakhstan on Thursday afternoon
  • expected that fragments of the probe would fall to Earth in January or February although the exact date would depend on external factors
  • One expert said that its surprise show of life had generated hope that the probe could be brought down back to Earth safely
  • ...1 more annotation...
  • November 24
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

Astrophysicists spy ultra-distant galaxy amidst cosmic 'dark ages' - 0 views

phys.org/...tra-distant-galaxy-cosmic.html

scibyte64 galaxy

shared by Mars Base on 20 Sep 12 - No Cached
  • combined power of NASA's Spitzer and Hubble space telescopes as well as a cosmic magnification effect, a team
  • has spotted what could be the most distant galaxy ever detected.
  • Light from the young galaxy captured by the orbiting observatories shone forth when the 13.7-billion-year-old universe was just 500 million years old
  • ...19 more annotations...
  • This galaxy is the most distant object we have ever observed with high confidence
  • Future work involving this galaxy—as well as others like it that we hope to find—will allow us to study the universe's earliest objects and how the Dark Ages ended
  • traveled approximately 13.2 billion light-years
  • the universe was just 3.6 percent
  • Objects at these extreme distances are mostly beyond the detection sensitivity of today's largest telescopes
  • astronomers rely on "gravitational lensing
  • predicted by Albert Einstein a century ago
  • gravity of foreground objects warps and magnifies the light from background objects
  • brightening the remote object some 15 times and bringing it into view.
  • small and compact, containing only about 1 percent of the Milky Way's mass
  • leading cosmological theories, the first galaxies should indeed have started out tiny
  • then progressively merged
  • omers plan to study the rise of the first stars and galaxies and the epoch of reionization with the successor to both Spitzer and Hubble—NASA's James Webb Telescope, slated for launch in 2018
  • newly described distant galaxy will likely be a prime target.
  • first galaxies likely played the dominant role in the epoch of reionization
  • event that signaled the demise of the universe's Dark Ages
  • About 400,000 years after the Big Bang, neutral hydrogen gas formed from cooling particles
  • these earliest galaxies is thought to have caused the neutral hydrogen strewn throughout the universe to ionize, or lose an electron
  • during the epoch of reionization, the lights came on in the universe
Mars Base

Intraplate Quakes Signal Tectonic Breakup - Science News - 0 views

www.sciencenews.org/...quakes_signal_tectonic_breakup

scibyte65 TectonicPlate

shared by Mars Base on 27 Sep 12 - No Cached
  • The first April 11 quake unzipped four perpendicular faults one after another in less than two minutes
  • They continued to resonate around the globe, triggering big aftershocks as far away as Mexico, a third study finds.
  • the number of quakes of magnitude 5.5 or greater, located more than 1,500 kilometers from the April 11 quakes, went up nearly fivefold for six days afterward
  • ...6 more annotations...
  • Most giant quakes don’t trigger temblors so far away
  • The biggest
  • was a magnitude 7 in Baja California, about 22 hours afterward
  • the triggered quakes are well below magnitude 5
  • The difference, Pollitz says, lay in the strike-slip nature of the April 11 quakes
  • fault geometry allows the stress of a crustal movement to propagate much farther across the planet’s surface
Mars Base

Telescope spies water plumes on dwarf planet Ceres - 0 views

phys.org/...spies-plumes-dwarf-planet.html

scibyte117 Asteroid Ceres

shared by Mars Base on 23 Jan 14 - No Cached
  • Scientists
  • have made the first definitive detection of water vapor on the largest and roundest object in the asteroid belt, Ceres.
  • Plumes of water vapor are thought to shoot up periodically from Ceres when portions of its icy surface warm slightly
  • ...26 more annotations...
  • Ceres is classified as a dwarf planet, a solar system body bigger than an asteroid and smaller than a planet.
  • "This is the first time water vapor has been unequivocally detected on Ceres or any other object in the asteroid belt and provides proof that Ceres has an icy surface and an atmosphere,"
  • Michael Küppers of ESA in Spain
  • NASA's Dawn mission, which is on its way to Ceres now after spending more than a year orbiting the large asteroid Vesta
  • Dawn is scheduled to arrive at Ceres in the spring of 2015, where it will take the closest look ever at its surface.
  • will map the geology and chemistry of the surface in high resolution
  • International Astronomical Union, the governing organization responsible for naming planetary objects
  • Ceres was known as the largest asteroid in our solar system
  • reclassified Ceres as a dwarf planet because of its large size. It is roughly 590 miles (950 kilometers) in diameter
  • When it first was spotted in 1801, astronomers thought it was a planet orbiting between Mars and Jupiter
  • Scientists believe Ceres contains rock in its interior with a thick mantle of ice that, if melted, would amount to more fresh water than is present on all of Earth
  • The materials making up Ceres likely date from the first few million years of our solar system's existence and accumulated before the planets formed.
  • Until now, ice had been theorized to exist on Ceres but had not been detected conclusively
  • far-infrared vision to see, finally, a clear spectral signature of the water vapor. But
  • did not see water vapor every time it looked
  • spied water vapor four different times, on one occasion there was no signature.
  • what scientists think is happening
  • when Ceres swings through the part of its orbit that is closer to the sun, a portion of its icy surface becomes warm enough to cause water vapor to escape in plumes
  • a rate of about 6 kilograms (13 pounds) per second
  • When Ceres is in the colder part of its orbit, no water escapes
  • The strength of the signal also varied over hours, weeks and months
  • water vapor plumes rotating in and out of Herschel's views as the object spun on its axis
  • This enabled the scientists to localize the source of water to two darker spots on the surface of Ceres
  • previously seen by NASA's Hubble Space Telescope and ground-based telescopes. The dark spots might be more likely to outgas because dark material warms faster than light material.
  • "The lines are becoming more and more blurred between comets and asteroids," said Seungwon Lee of JPL
  • Paul von Allmen, also of JPL. "We knew before about main belt asteroids that show comet-like activity, but this is the first detection of water vapor in an asteroid-like object."
Mars Base

Rats induced into hibernation-like state | Life | Science News - 0 views

www.sciencenews.org/...ed_into_hibernation-like_state

scibyte101 hibernate

shared by Mars Base on 05 Sep 13 - No Cached
  • Rats spent hours in a state of chilly suspended animation after researchers injected a compound into the animals in a cold room
  • animals’ heart rates slowed, brain activity became sluggish and body temperature plummeted.
  • Lowering the body temperature of a nonhibernating mammal is really hard
  • ...20 more annotations...
  • As temperatures inside the body fall, several failsafe systems spring into action
  • Blood vessels near the skin squeeze tight to hold warmth in, the body starts to shiver and brown fat, a tissue that’s especially plentiful in newborns, starts to produce heat
  • colleagues bypassed the rats’ defenses against the cold with a compound that’s similar to adenosine, a molecule in the body that signals sleepiness
  • After about an hour in a room chilled to 15° Celsius, the rats grew lethargic
  • brain waves slowed, their blood pressure dropped and their heart grew sluggish, occasionally skipping beats
  • The rats’ core temperature dropped from about 38°  to about 30° C, or 80° Fahrenheit
  • measured even lower temperatures in further experiments — rats’ core body temperature reached 15° C or about 57° F.
  • The rats weren’t in a coma, nor were they asleep or truly hibernating
  • Hibernating animals’ metabolisms plummet and their temperatures sink much lower
  • an Arctic ground squirrel, for instance, cools to about —3° C when it hibernates
  • It’s a new state
  • don’t really know what it is
  • In the experiment, loud noises and tail pinches failed to arouse the rats.
  • They didn’t eat or drink. Occasionally, one would slither into a corner, but for the most part, the animals stayed still for up to 6 hours
  • In unpublished experiments, Tupone has kept the animals in the unresponsive state for 24 hours, he says.
  • Warming the room coaxed the rats out of their torpor
  • The recovery process takes about 12 hours, during which the animals ate and drank voraciously
  • After recovering, the animals were alert, moved around their cages normally and slept when tired
  • When people have heart attacks or strokes, clinicians can use ice packs or frigid water to chill people and prevent further tissue damage
  • those methods of cooling take time and can have dangerous side effects
Mars Base

China's Jade Rabbit Lunar Rover Comes Back to Life After Malfunction - 0 views

www.scienceworldreport.com/...omes-back-life-malfunction.htm

scibyte120 ChineseSpaceProgram

shared by Mars Base on 14 Feb 14 - No Cached
  • China's state news agency, Xinhua, reported
  • that the rover
  • recovered from its previous non-responsive state and is now fully awake and able to receive signals
  • ...3 more annotations...
  • China's lunar program spokesman Pei Zhaoyu told Xinhua
  • the rover was reported to have been lost after it failed to communicate with Chinese mission controllers
  • various media outlets around the world filed an obituary for the lunar rover after Xinhua reported its alleged death
Mars Base

China's Yutu Moon Rover Alive and Awake for 3rd Lunar Day of Exploration despite Malfun... - 0 views

www.universetoday.com/...xploration-despite-malfunction

scibyte120 ChineseSpaceProgram

shared by Mars Base on 15 Feb 14 - No Cached
  • As night fell on Jan. 25, the rover entered its second two week long period of dormancy just as the rover “experienced a mechanical control abnormality,” according to a report by China’s official government newspaper, The People’s Daily.
  • concerned that it might not be able to survive the extremely low temperatures during the lunar night
  • Experts wer
  • ...5 more annotations...
  • Each lunar day and night lasts for alternating periods of 14 Earth days
  • During each long night, the Moon’s temperatures plunge dramatically to below minus 180 Celsius, or minus 292 degrees Fahrenheit
  • The 140 kg Yutu robot is located some 100 m south of the lander.
  • February 13
  • (Feb. 12) amateur radio operators at UHF-satcom reported detection of a signal from Yutu.
Mars Base

News in Brief: Distant radio-wave pulses spotted | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/...tant_radio-wave_pulses_spotted

scibyte100 RadioSignal

shared by Mars Base on 09 Jul 13 - No Cached
  • four recently detected radio signals disappeared only milliseconds after arriving at Earth
  • only the second detection ever of radio bursts emanating from beyond the Milky Way
  • Picked up by an international team of astronomers at the Parkes Radio Telescope in Australia
  • ...10 more annotations...
  • the powerful radio pulses emanate from sources 5 billion to nearly 11 billion light years away
  • these sources remains a mystery
  • but “clearly they’re very energetic events, probably cataclysmic.”
  • One-time radio pulses have been hard to detect
  • today’s telescopes capture radio waves from such a small fraction of the sky
  • the instruments lack the ultrafast time resolution required to pinpoint the short-lived bursts
  • The four new blips may add weight to the only other extragalactic radio burst ever witnessed, reported seven years
  • only had one burst
  • wondered whether it was
  • artifact
Mars Base

Magma Boils Beneath Antarctic Ice | Science/AAAS | News - 0 views

news.sciencemag.org/...ma-boils-beneath-antarctic-ice

scibyte110

shared by Mars Base on 19 Nov 13 - No Cached
  • Marie Byrd Land is a desolate region of Antarctica buried deep beneath the West Antarctic Ice Sheet
  • Historic eruptions have punctured the ice sheet, creating a chain of volcanoes amid the ice
  • researchers have shown that molten rock still stirs deep underground
  • ...24 more annotations...
  • Only the largest eruptions could melt all the ice above them and poke through to the surface, but even smaller eruptions could potentially cause global sea level to rise, although no one knows how big the rise might be
  • The crust is thinned by the West Antarctic Rift System, a series of giant rift valleys beneath the ice sheet
  • erupted lava from underground magma chambers has burst through the ice repeatedly over geological history as the plates moved over the top
  • No one knew whether magma was still stirring
  • until seismic monitoring stations were installed on the ice between 2007 and 2010.
  • Researchers built the stations to study the shifting crustal blocks of the West Antarctic Rift System
  • But seismologist
  • found another use
  • They noticed a series of small earthquakes, mainly occurring during two “seismic swarms” in January and February 2010 and March 2011
  • These earthquakes were unusual: The ground was shaking much more slowly during the quakes than one would expect from the plates grinding against each other
  • looked at two different types of waves that come in—the P wave, which is the primary wave, and the S wave, which is the secondary wave
  • calculations revealed that the waves had come from 25 to 40 kilometers below Earth's surface and were centered around a point
  • approximately the point the volcanic activity should have reached if it had continued the linear trend of volcanoes to the south
  • The exact cause of these deep quakes is not understood, but they are thought to result from the movement of magma deep below active or soon-to-be active volcanoes
  • They found that the area showed a slightly higher magnetic field than the surrounding area and that there was a bump in the crust—common signals of magmatic activity
  • Radar mapping also indicated a layer of volcanic ash embedded in the ice
  • probably
  • from an eruption of Mount Waesche about 8000 years ago—very recent geological history
  • There is no evidence of an actual eruption since then, but, because magma is still moving deep under the Earth, an eruption could occur at any time
  • The current center of volcanic activity is covered by at least 1 kilometer of ice, and it would take an exceptionally large eruption to melt all this
  • But an eruption could make its presence felt in subtler ways. As fresh snow adds to their own mass, ice sheets flow downward into the sea
  • melting the base of the ice sheet, an eruption could speed up this flow, potentially raising the level of the ocean. No one knows how significant such a rise might be
  • Any effect on the ice sheet above, and thus any effect on the oceans, would probably be quite small
  • a proper study is needed to find out how significant volcanic activity could be to future sea levels
Mars Base

A Sunny Outlook for NASA Kepler's Second Light | NASA - 0 views

www.nasa.gov/...-for-nasa-keplers-second-light

scibyte110 scibyte111 Kepler

shared by Mars Base on 26 Nov 13 - No Cached
  • A repurposed Kepler Space telescope may soon start searching the sky again.
  • A new mission concept, dubbed K2, would continue Kepler's search for other worlds, and introduce new opportunities to observe star clusters, young and old stars, active galaxies and supernovae
  • In May, the Kepler spacecraft lost the second of four gyroscope-like reaction wheels, which are used to precisely point the spacecraft, ending new data collection for the original mission
  • ...14 more annotations...
  • required three functioning wheels to maintain the precision pointing necessary to detect the signal of small Earth-sized exoplanets
  • With the failure of a second reaction wheel, the spacecraft can no longer precisely point at the mission's original field of view. The culprit is none other than our own sun
  • pushes the spacecraft around
  • the pressure exerted when the photons of sunlight strike the spacecraft
  • Without a third wheel to help counteract the solar pressure, the spacecraft's ultra-precise pointing capability cannot be controlled in all directions.
  • Kepler mission and Ball Aerospace engineers have developed an innovative way of recovering pointing stability by maneuvering the spacecraft so that the solar pressure is evenly distributed across the surfaces of the spacecraft
  • To achieve this level of stability, the orientation of the spacecraft must be nearly parallel to its orbital path around the sun
  • This technique of using the sun as the 'third wheel' to control pointing is currently being tested on the spacecraft and early results are already coming i
  • During a pointing performance test in late October, a full frame image of the space telescope's full field of view was captured showing part of the constellation Sagittarius
  • Photons of light from a distant star field were collected over a 30-minute period and produced an image quality within five percent of the primary mission image quality
  • Additional testing is underway to demonstrate the ability to maintain this level of pointing control for days and weeks.
  • The K2 mission concept has been presented to NASA Headquarters
  • A decision to proceed to the 2014 Senior Review – a biannual assessment of operating missions – and propose for budget to fly K2 is expected by the end of 2013
  • For four years, the space telescope simultaneously and continuously monitored the brightness of more than 150,000 stars, recording a measurement every 30 minutes.
Mars Base

NASA Finds Ingredient for Plastic on Saturn's Moon Titan | Space.com - 0 views

www.space.com/-titan-plastic-ingredient.html

scibyte105 ViewerFeedback titan

shared by Mars Base on 05 Oct 13 - No Cached
  • a chemical essential for the creation of plastic on Earth has been found in
  • Saturn's largest Titan
  • NASA's Cassini spacecraft currently orbiting Saturn, found that the atmosphere of Titan contains propylene
  • ...5 more annotations...
  • key ingredient of plastic containers, car bumpers and other everyday items on Earth
  • strung together in long chains to form a plastic called polypropylene
  • Scientists used Cassini's composite infrared spectrometer (CIRS) instrument, which measures infrared light given off by Saturn and its moon, made the discovery
  • When Voyager 1 conducted the first close flyby of the moon in 1980, it recognized gasses in the moon's brown atmosphere as hydrocarbons.
  • measurement was very difficult to make because propylene's weak signature is crowded by related chemicals with much stronger signals
Mars Base

New strategy to treat multiple sclerosis shows promise in mice - 0 views

medicalxpress.com/...y-multiple-sclerosis-mice.html

scibyte106 MultipleSclerosis

shared by Mars Base on 12 Oct 13 - No Cached
  • Scientists
  • have identified a set of compounds that may be used to treat multiple sclerosis (MS) in a new way
  • existing MS therapies
  • ...36 more annotations...
  • ppress the immune system
  • the compounds boost a population of progenitor cells that can in turn repair MS-damaged nerve fibers
  • cautioned that benztropine is a drug with dose-related adverse side effects, and has yet to be proven effective at a safe dose in human MS patients
  • the newly identified compounds, a Parkinson's disease drug called benztropine, was highly effective in treating a standard model of MS in mice, both alone and in combination with existing MS therapies
  • MS currently affects more than half a million people in North America and Europe, and more than two million worldwide
  • precise triggers are unknown, but certain infections and a lack of vitamin D are thought to be risk factors
  • In MS, immune cells known as T cells infiltrate the upper spinal cord and brain
  • causing inflammation and ultimately the loss of an insulating coating called myelin on some nerve fibers
  • As nerve fibers lose this myelin coating, they lose their ability to transmit signals efficiently, and in time may begin to degenerate
  • resulting symptoms, which commonly occur in a stop-start, "relapsing-remitting" pattern, may include limb weakness, numbness and tingling, fatigue, vision problems, slurred speech, memory difficulties and depression, among other problems
  • Current therapies
  • aim to suppress the immune attack that de-myelinates nerve fibers. But they are only partially effective and are apt to have significant adverse side effects
  • the new study
  • aimed at restoring a population of progenitor cells called oligodendrocytes
  • These cells normally keep the myelin sheaths of nerve fibers in good repair and in principle could fix these coatings after MS damages them
  • oligodendrocyte numbers decline sharply in MS, due to a still-mysterious problem with the stem-like precursor cells that produce them
  • team screened a library of about 100,000 diverse compounds for any that could potently induce OPCs to mature or "differentiate."
  • Several compounds scored well
  • benztropine, had been well characterized and indeed was already FDA-approved for treating Parkinson's disease
  • tests, benztropine showed a powerful ability to prevent autoimmune disease and also was effective in treating it after symptoms had arisen
  • virtually eliminating the disease's ability to relapse
  • benztropine on its own worked about as well as existing treatments, it also showed a remarkable ability to complement these existing treatments
  • two first-line immune-suppressant therapies, interferon-beta and fingolimod
  • Adding even a suboptimal level of benztropine
  • allowed
  • to cut the dose of fingolimod by 90%
  • the same disease-modifying effect as a normal dose
  • that dose-lowering could translate into a big reduction in
  • potentially serious side effects
  • researchers confirmed that benztropine works against disease in this mouse model by boosting the population of mature oligodendrocytes
  • in turn restore the myelin sheaths of damaged nerves
  • even as the immune attack continues
  • benztropine-treated mice showed no change in the usual signs of inflammation, yet their myelin was mostly intact, suggesting that it was probably being repaired as rapidly as it was being destroyed
  • Benztropine is known to have multiple specific effects on brain cells, including the blocking of activity at acetylcholine and histamine receptors and a boosting of activity at dopamine receptors
  • hope to learn more about how
  • its molecular structure might be optimized for this purpose
Mars Base

How Our Brain Balances Old and New Skills - 0 views

www.scienceworldreport.com/...alances-old-and-new-skills.htm

scibyte113 BrainTraining

shared by Mars Base on 12 Dec 13 - No Cached
  • To learn new motor skills, the brain must be plastic: able to rapidly change the strengths of connections between neurons, forming new patterns that accomplish a particular task
  • if the brain were too plastic, previously learned skills would be lost too easily.
  • A new computational model developed by MIT neuroscientists explains how the brain maintains the balance between plasticity and stability
  • ...31 more annotations...
  • and how it can learn very similar tasks without interference between them.
  • The key
  • is that neurons are constantly changing their connections with other neurons
  • not all of the changes are functionally relevant - they simply allow the brain to explore many possible ways to execute a certain skill, such as a new tennis stroke
  • As the brain learns a new motor skill, neurons form circuits that can produce the desired output
  • according to this theory
  • As the brain explores different solutions, neurons can become specialized for specific tasks
  • brain is always trying to find the configurations that balance everything so you can do two tasks, or three tasks, or however many you're learning
  • Perfection is usually not achieved on the first try, so feedback from each effort helps the brain to find better solutions
  • complications arise when the brain is trying to learn many different skills at once
  • Because the same distributed network controls related motor tasks, new modifications to existing patterns can interfere with previously learned skills.
  • particularly tricky when you're learning very similar things
  • such as two different tennis strokes
  • computer chip,
  • instructions for each task would be stored in a different location on the chip.
  • the brain is not organized like a computer chip. Instead, it is massively parallel and highly connected - each neuron connects to, on average, about 10,000 other neurons
  • That connectivity offers an advantage, however, because it allows the brain to test out so many possible solutions to achieve combinations of tasks
  • neurons
  • have a very low signal to noise ratio, meaning that they receive about as much useless information as useful input from their neighbors
  • The constant changes in these connections,
  • researchers call hyperplasticity
  • balanced by another inherent trait of
  • Most models of neural activity don't include noise, but the MIT team says noise is a critical element of the brain's learning ability
  • This model helps to explain how the brain can learn new things without unlearning previously acquired skills
  • the paper shows is that, counterintuitively, if you have neural networks and they have a high level of random noise, that actually helps instead of hindering the stability problem
  • Without noise, the brain's hyperplasticity would overwrite existing memories too easily
  • low plasticity would not allow any new skills to be learned, because the tiny changes in connectivity would be drowned out by all of the inherent noise
  • The constantly changing connections explain why skills can be forgotten unless they are practiced often, especially if they overlap with other routinely performed tasks
  • skills such as riding a bicycle, which is not very similar to other common skills, are retained more easily
  • Once you've learned something, if it doesn't overlap or intersect with other skills, you will forget it but so slowly that it's essentially permanent
  • researchers are now investigating whether this type of model could also explain how the brain forms memories of events, as well as motor skills
Mars Base

Using thoughts to control airplanes -- ScienceDaily - 0 views

www.sciencedaily.com/...140527101454.htm

scibyte132

shared by Mars Base on 27 May 14 - No Cached
  • Scientists have now demonstrated the feasibility of flying via brain control -- with astonishing accuracy
  • first breakthrough
  • succeeded in demonstrating that brain-controlled flight is indeed possible -- with amazing precision
  • ...8 more annotations...
  • Seven subjects took part in the flight simulator tests
  • They had varying levels of flight experience, including one person without any practical cockpit experience whatsoever
  • The accuracy with which the test subjects stayed on course by merely thinking commands would have sufficed, in part, to fulfill the requirements of a flying license test
  • Several of the subjects also managed the landing approach under poor visibility
  • scientists are now focusing in particular on the question of how the requirements for the control system and flight dynamics need to be altered to accommodate the new control method
  • Normally, pilots feel resistance in steering and must exert significant force when the loads induced on the aircraft become too large
  • This feedback is missing when using brain control
  • The researchers are thus looking for alternative methods of feedback to signal when the envelope is pushed too hard, for example
  • Mars Base on 27 May 14
     
    Using thoughts to control airplanes
Mars Base

New drug raises potential for cancer treatment revolution - 0 views

medicalxpress.com/...ncer-treatment-revolution.html

scibyte125 Cancer

shared by Mars Base on 24 Mar 14 - No Cached
  • A new study
  • has developed a new drug that can manipulate the body's natural signalling and energy systems, allowing the body to attack and shut down cancerous cells.
  • ZL105,
  • ...20 more annotations...
  • the drug is a compound based on the precious metal iridium
  • The study has found ZL105 could potentially replace currently used anticancer drugs
  • which become less effective over time, cause a wide-range of side-effects and damage healthy cells as well as cancerous.
  • study co-author
  • said "The energy-producing machinery in cancer cells works to the limit as it attempts to keep up with quick proliferation and invasion
  • This makes cancer cells susceptible to minor changes in the cell 'power-house'.
  • drug pushes cancer cells over the limit causing them to slow and shut down, whilst normal cells can cope with its effects
  • Preliminary data indicate that the novel drug may be ten times more effective in treating ovarian, colon, melanoma, renal, and some breast cancers, according to data obtained by the US National Cancer Institute
  • researchers now aim to expand the study to cancers that are inherently resistant to existing drugs and to those which have developed resistance after a first round of chemotherapy treatments.
  • Existing cancer treatments often become less effective after the first course, as cancer cells learn how they are being attacked
  • The drug we have developed is a catalyst and is active at low doses
  • It can attack cancer cells in multiple ways at the same time, so the cancer is less able to adapt to the treatment
  • means the new drugs could be much more effective than existing treatments
  • Platinum-based drugs are used in nearly 50% of all chemotherapeutic regimens
  • damaging DNA and cannot select between cancerous and non-cancerous cells
  • leading to a wide-range of side-effects from renal failure to neurotoxicity, ototoxicity, nausea and vomiting
  • the new iridium-based drug is specifically designed not to attack DNA,
  • growth
  • novel mechanism of action, meaning that it could not only dramatically slow down and halt cancer growth, but also significantly reduce the side effects
  • This research could also lead to substantial improvements in cancer survival rates
Mars Base

Guest Post: No turning back, NASA ISEE-3 Spacecraft Returning to Earth after a 36 Year ... - 0 views

www.universetoday.com/...-earth-after-a-36-year-journey

scibyte132 ISEE-3

shared by Mars Base on 25 May 14 - No Cached
  • 30 years later and documents and magnetic tapes have predictably disappeared.
  • The software and hardware to program, command and transmit to ISEE-3 are long gone
  • An independent team of engineers
  • ...5 more annotations...
  • recovering old imagery on magnetic tape reels from the first lunar orbiter missions),
  • operating outside the ranks and hallways of NASA
  • to accomplish a landmark achievement: to turn on, command and maneuver a NASA spacecraft long ago abandoned
  • Amateur radio operators now have technology sufficient to acquire the signal and through the internet are also a part of the recovery effort
  • without the original hardware transmitter, today’s high-speed electronics are able to emulate in software the hardware from 36 years ago
Mars Base

Lake on Saturn's Largest Moon May Have Waves - Scientific American - 0 views

www.scientificamerican.com/...-s-largest-moon-may-have-waves

scibyte134 titan

shared by Mars Base on 05 Jun 14 - No Cached
  • meras on NASA's spacecraft Cassini recently saw what appear to be waves on one of Titan's largest methane lakes
  • a signal scientists have long searched for but never found
  • If confirmed, the discovery would mark the first time waves have been seen outside Earth.
  • ...13 more annotations...
  • team found patterns in the sunlight reflecting off a northern lake called Punga Mare that they interpret as two-centimeter-high waves
  • There
  • may be a mudflat instead of a deep lake, and a shallow film of liquid on top may be the cause of the unique light signature
  • If life on Titan exists,
  • the best place to look
  • is in large bodies of liquid—the kind that form waves
  • Waves on Titan
  • would confirm that the lakes actually are deep reservoirs of methane and ethane,
  • True liquid bodies would also make a robotic spacecraft mission to explore Titan's habitability more feasible
  • By 2017 scientists should know for certain whether what they are seeing is indeed caused by waves
  • Cassini has been observing the moon during its northern winter, when weak winds are at work
  • As spring
  • over the next few years, bringing stronger winds to kick up seas, the probe should capture more definitive evidence of waves if they exist
Mars Base

ISEE-3 Reboot Project Update: BULLSEYE! and More - Space College - 0 views

spacecollege.org/...-update-bullseye-and-more.html

scibyte133 ISEE-3

shared by Mars Base on 02 Jun 14 - No Cached
  • spacecraft has two transponders,
  • transponder A and Transponder B
  • Transponder B is normally the engineering telemetry transponder and transponder A is the ranging transponder
  • ...32 more annotations...
  • The final state of the spacecraft before was to have both of the transponders transmitters active and that is what people around the world have been tracking.
  • the spacecraft is set up with a lot of redundancy so you can use either transponder A or B to send telemetry or range
  • We tried several times to command the spacecraft's B transponder at 2041.9479 MHz into the mode where it normally sends engineering telemetry
  • did not work
  • Then we tried the same process on transponder A
  • modulation from the output of the telemetry system
  • The initial command was just to turn engineering telemetry on at 512 bits/second. This was successful.
  • successfully commanded the spacecraft into engineering telemetry mode.
  • initial verification
  • later
  • through the A transponder's receiver we commanded through the B transponder's command decoder to output engineering telemetry through transponder B's transmitter
  • verified so far the following systems on the spacecraft
  • 1. Transponder A receiver
  • 2. Transponder A's Command Decoder and Data Handling Unit
  • 3. Transponder B's Command Decoder and Data Handling Unit
  • tried to command the spacecraft into 64 bits/second mode, which was a mode that is much more complicated to set up and we did not get working successfully during the limited time that the spacecraft is visible from Arecibo
  • need to do this so that the smaller dishes at Morehead State and Bochum will have a positive signal margin so that we can record several hours of data
  • neither of the ISEE-3/ICE receivers had met their specification in testing
  • for -120 dbm sensitivity
  • receiver A was tested at about -114 dbm, and Receiver B at -111 dbm
  • after our end to end systems test we had an earthquake
  • how observations could be affected by vibrations in the dome structure as it translates during an observation and then that happened
  • later processed our first day's data dump from the spacecraft and we received 49 full frames of data at a bit rate of 512 bits/second
  • there were no errors on the downlink
  • milestones related to commanding and receiving data
  • 1. Successful commanding multiple times of ISEE-3/ICE
  • 2. Received engineering telemetry from both data multiplexing units on the spacecraft
  • 3. Successful demodulation on the ground of the received data, through the output of bits
  • 4. Verification of good data at 512 bits/sec, including frame synchronization, correct number of bits/frame, and with no errors, showing a very strong 30+ db link margin through Arecibo
  • If we can maneuver the spacecraft by June 17th we get the very small delta V number
  • this starts to climb rapidly as the spacecraft gets closer to the moon
  • cannot at this time rule out a lunar impact.
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