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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

MAVEN thunders to Space on Journey to Study Red Planet's Watery History and Potential f... - 0 views

www.universetoday.com/...history-and-potential-for-life

scibyte110 MAVEN

shared by Mars Base on 19 Nov 13 - No Cached
  • NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) space probe thundered to space
  • Nov. 18
  • from Cape Canaveral Air Force Station’s Space Launch Complex 41 at 1:28 p.m. EST atop a powerful Atlas V rocket
  • ...19 more annotations...
  • It will take the spacecraft 10 months to reach the Red Planet, with arrival scheduled for Sept. 22, 2014
  • MAVEN’s purpose is to accomplish world class science after arriving at Mars and completing a check-out period before it can finally begin collecting science data
  • MAVEN will answer key questions about the evolution of Mars, its geology and the potential for the evolution of life
  • Mars was once wet billions of years ago,
  • Now it’s a cold arid world, not
  • hospitable to life
  • want to determine what were the drivers of that change
  • What is the history of Martian habitability, climate change and the potential for life
  • MAVEN will study Mars upper atmosphere to explore how the Red Planet may have lost its atmosphere over billions of years
  • It will measure current rates of atmospheric loss to determine how and when Mars lost its atmosphere and water
  • The MAVEN probe carries nine sensors in three instrument suites
  • The Particles and Fields Package,
  • contains six instruments to characterize the solar wind and the ionosphere of Mars.
  • The Remote Sensing Package,
  • will determine global characteristics of the upper atmosphere and ionosphere.
  • The Neutral Gas and Ion Mass Spectrometer,
  • will measure the composition of Mars’ upper atmosphere.
  • Over the course of its one-Earth-year primary mission, MAVEN will observe all of Mars’ latitudes at altitudes ranging from 93 miles to more than 3,800 miles.
  • MAVEN will execute five deep dip maneuvers during the first year, descending to an altitude of 78 miles. This marks the lower boundary of the planet’s upper atmosphere.
Mars Base

New Era of Neutrino Astronomy Begins at the South Pole - 0 views

www.scienceworldreport.com/...stronomy-begins-south-pole.htm

scibyte110 Neutrinos

shared by Mars Base on 23 Nov 13 - No Cached
  • Astrophysicists have managed to detect and record the mysterious phenomena known as cosmic neutrinos
  • nearly massless particles that stream to Earth at the speed of light from outside our solar system, striking the surface in a burst of energy that can be as powerful as a baseball pitcher's fastball
  • In this particular study, the researchers observed 28 very high-energy particle events with the use of the IceCube Neutrino Observatory in Antarctica
  • ...8 more annotations...
  • These events constitute the first solid evidence for astrophysical neutrinos from cosmic sources
  • The sources of neutrinos, and the question of what could accelerate these particles, has been a mystery for more than 100 years
  • IceCube is made up of 5,160 digital optical modules suspended along 86 strings embedded in ice beneath the South Pole
  • It detects neutrinos through the tiny flashes of blue light, called Cherenkov light, produced when neutrinos interact in the ice.
  • Computers then collect near-real-time data from the optical sensors and send information about interesting events north via satellite
  • astrophysical neutrinos move in straight lines unimpeded by outside forces, they can act as pointers to the place in the galaxy where they originated
  • This, in turn, can tell astronomers quite a bit out our universe
  • The 28 events recorded so far are too few to point to any particular location
Mars Base

Neutrino Detector Finds Elusive Extraterrestrial Particles in 'Major Breakthrough' | Sp... - 0 views

www.space.com/al-particles-breakthrough.html

scibyte110 Neutrinos

shared by Mars Base on 23 Nov 13 - No Cached
  • scientists have pondered the source of cosmic rays, which contain the energy of a rifle bullet in a single atomic nucleus
  • It's thought that objects such as supernovas, black holes or gamma ray bursts mayproduce cosmic rays, but their origin is difficult to detect
  • Instead, scientists look for neutrinos — subatomic particles with no charge and very little mass — produced when cosmic rays interact with their surroundings
  • ...2 more annotations...
  • Billions of neutrinos pass through a square centimeter of Earth every second, and only a tiny fraction of them interact with matter
  • IceCube is located inside a cubic kilometer of ice beneath the South Pole. The observatory consists of 5,160 digital optical modules suspended from 86 strings
Mars Base

Mars Rover Curiosity Sidelined by Electrical Glitch | Space.com - 0 views

www.space.com/riosity-electrical-glitch.html

scibyte110 Curiosity

shared by Mars Base on 23 Nov 13 - No Cached
  • (Nov. 17), the mission team noticed a change in the voltage difference between the body of the Curiosity rover and its electricity-distributing power bus
Mars Base

New research aims to teach computers common sense - 0 views

phys.org/...2013-11-aims-common.html

scibyte110 ArtificiaIntelligence

shared by Mars Base on 25 Nov 13 - No Cached
  • Researchers are trying to plant a digital seed for artificial intelligence by letting a massive computer system browse millions of pictures and decide for itself what they all mean
  • The system at Carnegie Mellon University is called NEIL, short for Never Ending Image Learning
  • In mid-July, it began searching the Internet for images 24/7 and, in tiny steps, is deciding for itself how those images relate to each other
  • ...13 more annotations...
  • The goal is to recreate what we call common sense—the ability to learn things without being specifically taught
  • NEIL uses advances in computer vision to analyze and identify the shapes and colors in pictures, but it is also slowly discovering connections between objects on its own
  • the computers have figured out that zebras tend to be found in savannahs and that tigers look somewhat like zebras
  • In just over four months, the network of 200 processors has identified 1,500 objects and 1,200 scenes and has connected the dots to make 2,500 associations
  • Some of NEIL's computer-generated associations are wrong
  • "rhino can be a kind of antelope,"
  • "actor can be found in jail cell"
  • "news anchor can look similar to Barack Obama."
  • having a computer make its own associations is an entirely different type of challenge than programming a supercomputer to do one thing very well, or fast
  • humans constantly make decisions using "this huge body of unspoken assumptions," while computers don
  • humans can also quickly respond to some questions that would take a computer longer to figure out
  • "Could a giraffe fit in your car?" she asked. "We'd have an answer, even though we haven't thought about it" in the sense of calculating the giraffe's body mass
  • In the future, NEIL will analyze vast numbers of YouTube videos to look for connections between objects
Mars Base

Carnegie Mellon computer searches web 24/7 to analyze images and teach itself common sense - 0 views

phys.org/...-mellon-web-images-common.html

scibyte110 ArtificiaIntelligence

shared by Mars Base on 25 Nov 13 - No Cached
  • NEIL leverages recent advances in computer vision that enable computer programs to identify and label objects in images, to characterize scenes and to recognize attributes, such as colors, lighting and materials, all with a minimum of human supervision
  • since late July and already has analyzed three million images, identifying 1,500 types of objects in half a million images and 1,200 types of scenes in hundreds of thousands of images
  • sometimes, what NEIL finds can surprise even the researchers
  • ...5 more annotations...
  • a search for "apple" might return images of fruit as well as laptop computers
  • team had no idea that a search for F-18 would identify not only images of a fighter jet, but also of F18-class catamarans
  • As its search proceeds, NEIL develops subcategories of objects
  • tricycles can be for kids, for adults and can be motorized, or cars come in a variety of brands and models
  • it begins to notice associations – that zebras tend to be found in savannahs, for instance, and that stock trading floors are typically crowded
Mars Base

Mars Science Laboratory: Rover Team Working to Diagnose Electrical Issue - 0 views

mars.jpl.nasa.gov/...index.cfm

scibyte110 Curiosity

shared by Mars Base on 26 Nov 13 - No Cached
  • Science observations by NASA's Mars rover Curiosity have been suspended for a few days while engineers run tests to check possible causes of a voltage change detected on Nov. 17
  • "The vehicle is safe and stable, fully capable of operating in its present condition, but we are taking the precaution of investigating what may be a soft short," said Mars Science Laboratory Project Manager
  • The team detected a change in the voltage difference between the chassis and the 32-volt power bus that distributes electricity to systems throughout the rover
  • ...11 more annotations...
  • A "soft" short is a leak through something that's partially conductive of electricity, rather than a hard short such as one electrical wire contacting another
  • The level had been about 11 volts since landing day, and is now about 4 volts
  • The rover's electrical system is designed with the flexibility to work properly throughout that range and more -- a design feature called "floating bus."
  • Curiosity had already experienced one soft short on landing day in August 2012
  • A soft short can cause such a voltage change
  • That one was related to explosive-release devices used for deployments shortly before and after the landing
  • It lowered the bus-to-chassis voltage from about 16 volts to about 11 volts but has not affected subsequent rover operations
  • Soft shorts reduce the level of robustness for tolerating other shorts in the future, and they can indicate a possible problem in whichever component is the site of the short
  • Operations planned for Curiosity for the next few days are designed to check some of the possible root causes for the voltage change
  • Analysis so far has determined that the change appeared intermittently three times during the hours before it became persistent
  • The electrical issue did not cause the rover to enter a safe-mode status, in which most activities automatically cease pending further instructions, and there is no indication the issue is related to a computer reboot that triggered a "safe-mode" earlier this month
Mars Base

Mars Science Laboratory: Curiosity Resumes Science After Analysis of Voltage Issue - 0 views

mars.jpl.nasa.gov/...index.cfm

scibyte110 Curiosity

shared by Mars Base on 26 Nov 13 - No Cached
  • Activities over the weekend included use of Curiosity's robotic arm to deliver portions of powdered rock to a laboratory inside the rover
  • The powder has been stored in the arm since the rover collected it by drilling into the target rock "Cumberland" six months ago
  • Several portions of the powder have already been analyzed. The laboratory has flexibility for examining duplicate samples in different ways
  • ...12 more annotations...
  • The decision to resume science activities resulted from the success of work to diagnose the likely root cause of a Nov. 17 change in voltage
  • made a list of potential causes, and then determined which we could cross off the list, one by one
  • Science operations were suspended for six days while this analysis took priority
  • The likely cause is an internal short in Curiosity's power source, the Multi-Mission Radioisotope Thermoelectric Generator
  • this short does not affect operation of the power source or the rover
  • Similar generators on other spacecraft, including NASA's Cassini at Saturn, have experienced shorts with no loss of capability
  • Testing of another Multi-Mission Radioisotope Thermoelectric Generator over many years found no loss of capability in the presence of these types of internal shorts
  • early Nov. 23
  • that the rover had returned to its pre-Nov. 17 voltage level. This reversal is consistent with their diagnosis of an internal short in the generator on Nov. 17, and the voltage could change again
  • analysis work to determine the cause of the voltage change gained an advantage from an automated response by the rover's onboard software when it detected the voltage change
  • The rover stepped up the rate at which it recorded electrical variables, to eight times per second from the usual once per minute, and transmitted that engineering data in its next communication with Earth
  • In subsequent days, the rover performed diagnostic activities commanded by the team, such as powering on some backup hardware to rule out the possibility of short circuits in certain sensors
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

SOHO shows new images of Comet ISON - 0 views

phys.org/...11-soho-images-comet-ison.html

scibyte111 CometISON

shared by Mars Base on 28 Nov 13 - No Cached
  • scientists have been watching through many observatories to see if the comet has already broken up under the intense heat and gravitational forces of the sun
  • The comet is too far away to discern how many pieces it is in, so instead researchers carefully measure how bright it is,
  • Less light can sometimes mean that more of the material has boiled off and disappeared, perhaps pointing to a disintegrated comet
  • ...5 more annotations...
  • a disintegrating comet sometimes gives off more light, at least temporarily, so researchers look at the comet's pattern of behavior over the previous few days to work out what it may be doing.
  • At times observations have suggested ISON was getting dimmer and might already be in pieces
  • over Nov. 26-27, 2013, the comet once again brightened. In the early hours of Nov. 27, the comet appeared in the view of the European Space Agency/NASA mission the Solar and Heliospheric Observatory in the Large Angle and Spectrometric Coronagraph instrument
  • If the comet has already broken up, it should disintegrate completely as it makes its slingshot around the sun
  • This would provide a great opportunity for scientists to see the insides of the comet, and better understand its composition
Mars Base

ScienceShot: Comet ISON Could Be No More | Science/AAAS | News - 0 views

news.sciencemag.org/...ot-comet-ison-could-be-no-more

scibyte111 CometISON

shared by Mars Base on 28 Nov 13 - No Cached
  • ISON was
  • on course to swing by the sun less than one solar diameter above the sun’s searing surface on 28 November, Thanksgiving Day in the United States
Mars Base

India's MOM Mars Probe Images Earth's Children Prior to Nail Biting Red Planet Insertion - 0 views

www.universetoday.com/...il-biting-red-planet-insertion

scibyte111 India-MarsOrbiterMission

shared by Mars Base on 28 Nov 13 - No Cached
  • First ever image of Earth Taken by Mars Color Camera aboard India’s Mars Orbiter Mission
  • age is focused on the Indian subcontinent and captured from an altitude of 70,000 kilometers. Credit: ISRO
  • image was taken on Nov. 20 at around 1350 hrs (IST) from a height of almost 70,000 km above earth and has a spatial resolution of 3.5 km, said ISRO
  • ...2 more annotations...
  • The image also gives a rather good approximation of what MOM’s color camera will actually see
  • since the probe will enter a similarly highly elliptical orbit around Mars
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