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Mars Base

Astronomers discover planet that shouldn't be there - 0 views

phys.org/...tronomers-planet-shouldnt.html

scibyte112 exoplanet

shared by Mars Base on 06 Dec 13 - No Cached
  • An international team of astronomers
  • has discovered the most distantly orbiting planet found to date around a single, sun-like star
  • 11 times Jupiter's mass and orbiting its star at 650 times the average Earth-Sun distance
  • ...34 more annotations...
  • HD 106906 b
  • throws a wrench in planet formation theories
  • no model of either planet or star formation fully explains what we see
  • It is thought that planets close to their stars, like Earth, coalesce from small asteroid-like bodies born in the primordial disk of dust and gas that surrounds a forming star
  • this process acts too slowly to grow giant planets far from their star
  • Another proposed mechanism is that giant planets can form from a fast, direct collapse of disk material
  • primordial disks rarely contain enough mass in their outer reaches to allow a planet like HD 106906 b to form
  • Several alternative hypotheses have been put forward, including formation like a mini binary star system
  • binary star system can be formed when two adjacent clumps of gas collapse more or less independently to form stars, and these stars are close enough to each other to exert a mutual gravitation attraction and bind them together in an orb
  • It is possible that in the case of the HD 106906 system the star and planet collapsed independently from clumps of gas, but for some reason the planet's progenitor clump was starved for material and never grew large enough to ignite and become a star
  • one problem with this scenario is that the mass ratio of the two stars in a binary system is typically no more than 10-to-1.
  • the mass ratio is more than 100-to-1,
  • extreme mass ratio is not predicted from binary star formation theories – just like planet formation theory predicts that we cannot form planets so far from the host star
  • is also of
  • interest because researchers can still detect the remnant "debris disk" of material left over from planet and star formation.
  • potential to help us disentangle the various formation models
  • Future observations of the planet's orbital motion and the primary star's debris disk may help answer that question
  • At only 13 million years old, this young planet still glows from the residual heat of its formation
  • Because at 2,700 Fahrenheit (about 1,500 degrees Celsius) the planet is much cooler than its host star
  • it emits most of its energy as infrared rather than visible light
  • Earth
  • formed 4.5 billion years ago
  • about 350 times older than HD 106906 b.
  • Direct imaging observations require exquisitely sharp images, akin to those delivered by the Hubble Space Telescope
  • To reach this resolution from the ground requires a technology called Adaptive Optics, or AO
  • The team used the new Magellan Adaptive Optics (MagAO) system and Clio2 thermal infrared camera
  • mounted on the 6.5 meter-diameter Magellan telescope in the Atacama Desert in Chile to take the discovery image
  • MagAO was able to utilize its special Adaptive Secondary Mirror
  • 585 actuators, each moving 1,000 times a second, to remove the blurring of the atmosphere
  • optimized for thermal infrared wavelengths, where giant planets are brightest compared to their host stars
  • planets are most easily imaged at these wavelengths
  • The team was able to confirm that the planet is moving together with its host star by examining Hubble Space Telescope data taken eight years prior for another research program
  • This planet discovery is particularly exciting because it is in orbit so far from its parent star. This leads to many
  • questions about its formation history and composition
Mars Base

Scientists Identify Cause of Japan's Devastating 2011 Tsunami - 0 views

www.scienceworldreport.com/...s-devastating-2011-tsunami.htm

scibyte112 earthquakes

shared by Mars Base on 06 Dec 13 - No Cached
  • In March 2011, a devastating tsunami struck Japan's Tohoku region
  • Now, researchers have uncovered the cause of this tsunami, shedding light on what displaced the seafloor off the northeastern coast of Japan
  • Learning more about the 2011 tsunami and its causes is an important step for monitoring future events.
  • ...18 more annotations...
  • could help researchers provide earlier warnings
  • During their study
  • scientists underwent a 50-day expedition on the Japanese drilling vessel Chikyu
  • They then drilled three holes in the Japan Trench area in order to study the rupture zone of the 2011 earthquake
  • a fault in the ocean floor where two of Earth's major tectonic plates meet deep beneath the surface of the Pacific Ocean.
  • The conventional view among geologists
  • has been that deep beneath the seafloor, where rocks are strong, movements of the plates can generate a lot of elastic rebound
  • Closer to the surface of the seafloor, where rocks are softer and less compressed, this rebound effect was thought to taper off
  • In fact
  • the largest displacement of plates before the 2011 tsunami occurred in 1960 off the coast of Chile
  • That's when a powerful earthquake displaced seafloor plates by an average of 20 meters
  • The Tohoku earthquake, in contrast, displaced its own plates by 30 to 50 meters.
  • So what caused this unexpectedly violent slip
  • the fault itself is very thin--less than five meters thick in the area sampled.
  • makes it the thinnest plate boundary on Earth.
  • In addition, clay deposits that fill the narrow fault are made of extremely fine sediment, which makes it extremely slippery
  • these findings don't just show researchers a bit more about the past; they also have implications for the future
  • Other subduction zones in the northwest Pacific where this type of clay is present--from Russia's Kamchatka peninsula to the Aleutian Islands--may also be capable of generating similar, huge earthquakes
Mars Base

Mars Science Laboratory: Laser Instrument on NASA Mars Rover Tops 100,000 Zaps - 0 views

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

scibyte112 Curiosity

shared by Mars Base on 06 Dec 13 - No Cached
  • Curiosity
  • has passed the milestone of 100,000 shots fired by its laser.
  • The 100,000th shot was one of a series of 300 to investigate 10 locations on a rock called "Ithaca" in late October
  • ...7 more annotations...
  • at a distance of 13 feet, 3 inches (4.04 meters) from the laser and telescope on rover's mast
  • Chemistry and Camera instrument (ChemCam) uses the infrared laser to excite material in a pinhead-size spot on the target into a glowing, ionized gas, called plasma.
  • ChemCam observes that spark with the telescope and analyzes the spectrum of light to identify elements in the target
  • As of the start of December, ChemCam has fired its laser on Mars more than 102,000 times, at more than 420 rock or soil targets
  • The instrument has also returned more than 1,600 images taken by its remote micro-imager camera
  • Each pulse delivers more than a million watts of power for about five one-billionths of a second
  • The technique used by ChemCam, called laser-induced breakdown spectroscopy, has been used to assess composition of targets in other extreme environments, such as inside nuclear reactors and on the sea floor
Mars Base

Europa's ocean could help explain its jigsaw surface | Ars Technica - 0 views

arstechnica.com/...elp-explain-its-jigsaw-surface

scibyte113 Europa ViewerFeedback

shared by Mars Base on 06 Dec 13 - No Cached
  • Jupiter’s icy moon Europa
  • cracks appear in this facade
  • the cracks come in the form of jumbled pieces of ice that make up what are called the moon's “chaos terrains.”
  • ...5 more annotations...
  • It seems likely that the ocean has something to do with the chaos terrain, especially given the presence of salt there
  • To figure that out, however, we’d have to know something about how water circulates in that ocean
  • Circulation in the ocean would be driven by the heat from Europa’s interior
  • It’s been thought that the big-picture pattern might look something like the atmosphere of Jupiter, with alternating bands of eastward or westward flow.
  • difficulty of studying Europa’s
Mars Base

China's Maiden Moon Rover Mission Chang'e 3 Achieves Lunar Orbit - 0 views

www.universetoday.com/...oon-rover-achieves-lunar-orbit

scibyte112 ChineseSpaceProgram

shared by Mars Base on 09 Dec 13 - No Cached
  • China’s
  • moon landing probe successfully entered lunar orbit on Friday, Dec. 6
  • China’s ‘Yutu’ lunar lander is riding piggyback atop the four legged landing probe
  • ...2 more annotations...
  • Chang’e 3 is due to make a powered descent to the Moon’s surface on Dec. 14, firing the landing thrusters at an altitude of 15 km (9 mi) for a soft landing in a preselected area called the Bay of Rainbows or Sinus Iridum region.
  • The Bay of Rainbows is a lava filled crater located in the upper left portion of the moon as seen from Earth.
Mars Base

Curiosity Discovers Ancient Mars Lake Could Support Life - 0 views

www.universetoday.com/...t-mars-lake-could-support-life

scibyte112 Curiosity

shared by Mars Base on 10 Dec 13 - No Cached
  • ASA’s Curiosity rover has discovered evidence that an ancient Martian lake had the right chemical ingredients that could have sustained microbial life
  • these habitable conditions persisted until a more recent epoch than previously thought
  • researchers have developed a novel technique allowing Curiosity to accurately date Martian rocks for the first time ever
  • ...10 more annotations...
  • The ancient fresh water lake at the Yellowknife Bay area inside the Gale Crater landing site explored earlier this year
  • existed for periods spanning perhaps millions to tens of millions of years in length
  • before eventually evaporating completely after Mars lost its thick atmosphere.
  • the lake may have existed until as recently as 3.7 Billion years ago, much later than researchers expected
  • which means that life had a longer and better chance
  • before it was transformed into its current cold, arid state.
  • Researchers also announced that they are shifting the missions focus from searching for habitable environments to searching for organic molecules – the building blocks of all life as we know it.
  • the team believes they have found a way to increase the chance of finding organics preserved in the sedimentary rock layers
  • a mission that is now dedicated to the search for that subset of habitable environments which also preserves organic carbon
  • the ancient lake at Yellowknife Bay was likely about 30 miles long and 3 miles wide.
Mars Base

Ancient Mars Lake Could Have Supported Life, Curiosity Rover Shows | Space.com - 0 views

www.space.com/life-lake-curiosity-rover.html

scibyte112 Curiosity

shared by Mars Base on 10 Dec 13 - No Cached
  • The lake once covered a small portion of the 96-mile-wide (154 kilometers) Gale Crater
  • The lake could have potentially supported a class of microbes called chemolithoautotrophs, which obtain energy by breaking down rocks and minerals
  • Here on Earth, chemolithoautotrophs are commonly found in habitats beyond the reach of sunlight, such as caves and hydrothermal vents on the ocean floor
  • ...7 more annotations...
  • The shallow ancient lake may have been about 30 miles long by 3 miles wide (50 by 5 kilometers
  • the research team estimates that the lake existed for at least tens of thousands of years — and perhaps much longer, albeit on a possibly on-and-off basis
  • for times when the lake might have been dry, the groundwater's still there
  • The lack of weathering on Gale Crater's rim suggests that the area was cold when the lake existed
  • raising the possibility that a layer of ice covered the lake on a permanent or occasional basis
  • These are entirely viable habitable environments for chemolithoautotrophs
  • Curiosity was not designed to hunt for signs of life on Mars
Mars Base

Scientists Discover Untapped Freshwater Reserves Beneath the Oceans - 0 views

www.scienceworldreport.com/...eserves-beneath-the-oceans.htm

scibyte113 water

shared by Mars Base on 10 Dec 13 - No Cached
  • Australian scientists have identified vast freshwater reserves buried beneath the oceans
  • According to the latest report documented in the journal Nature
  • researchers have revealed the presence of nearly half a million cubic kilometres of low salinity water located beneath the seabed on the continental shelves
  • ...16 more annotations...
  • Located off Australia, China, North America and South Africa, the newly discovered fresh water reserves can be used to supply water to coastal cities
  • this water resource is a hundred times greater than the amount we've extracted from the Earth's sub-surface in the past century since 1900
  • groundwater scientists were very well aware of the presence of the freshwater reserves beneath the seafloor, but have assumed it to occur during unusual and extraordinary situations
  • this latest study reveals that the fresh and brackish aquifers under the seabed are a common phenomena
  • formed hundreds to thousands of years ago when the sea level was lower than what it is currently
  • rainwater penetrated into the ground and filled up the water tables in regions that are currently under sea
  • Nearly 20,000 years ago, the sea levels rose, the ice caps began melting and the areas were covered by oceans
  • Most of the aquifers today are protected from seawater by blankets of clay and sediments that are piled on top
  • These aquifers are not different from those found below land. Their salinity is low due to which they can be easily converted into drinking water
  • researchers propose two ways to gain access to these freshwater reserves
  • either be by constructing a platform and drilling into the seabed, which is expensive
  • Or drill from the mainland that is at a closer distance from the aquifer
  • Freshwater under the seabed is much less salty than seawater
  • it can be converted to drinking water with less energy than seawater desalination
  • also leave us with a lot less hyper-saline water
  • freshwater offshore should remember is that the water reserves are non-renewable and should be used carefully
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

Space Station Suffers Cooling System Shutdown, Some Systems Offline | Space.com - 0 views

www.space.com/on-cooling-system-problem.html

scibyte113 iss

shared by Mars Base on 12 Dec 13 - No Cached
  • Loop B
  • is struggling to keep up,
  • looking at some additional power downs in other modules to make sure that the highest priority loads get adequate cooling
  • ...1 more annotation...
  • it may require that astronauts go outside the International Space Station at some point to replace the pump module with a spare unit.
Mars Base

One-Way, Manned Mission To Mars Just Got Closer To Reality | Popular Science - 0 views

www.popsci.com/...n-mars-just-got-closer-reality

scibyte113 MarsOne

shared by Mars Base on 12 Dec 13 - No Cached
  • Mars One announced
  • Lockheed Martin and Surrey Satellite Technology Ltd. were awarded contracts to study and develop concepts for a Mars lander and a data link satellite,
  • for a 2018 exploratory mission
  • ...1 more annotation...
  • The mission's timetable has been pushed back by two years. The satellite was originally supposed to launch in 2016, with humans arriving by 2023. Now, Mars One is aiming for a 2025 colonization date. 
Mars Base

Update on Space Station Cooling System | NASA - 0 views

www.nasa.gov/...n-space-station-cooling-system

scibyte113 iss

shared by Mars Base on 13 Dec 13 - No Cached
  • Dec. 11, 2013
  • the pump module on one of the space station’s two external cooling loops automatically shut down when it reached pre-set temperature limits
  • These loops circulate ammonia outside the station to keep both internal and external equipment cool
  • ...4 more annotations...
  • suspect a flow control valve actually inside the pump module itself might not be functioning correctly
  • At no time was the crew or the station itself in any danger
  • ground teams did work to move certain electrical systems over to the second loop
  • Some non-critical systems have been powered down inside the Harmony node, the Kibo laboratory and the Columbus laboratory
Mars Base

Teams Working Cooling System Issue; Station Crew Carries on With Research | NASA - 0 views

www.nasa.gov/...-crew-carries-on-with-research

scibyte113 iss

shared by Mars Base on 13 Dec 13 - No Cached
  • Dec. 12, 2013
  • suspect a flow control valve actually inside the pump module itself might not be functioning correctly
  • hat flow control valve regulates the temperature of the ammonia in the loop so that when the ammonia is re-introduced into the heat exchanger on the Harmony node it does not freeze the water also flowing through the exchange
  • ...17 more annotations...
  • Mission managers have deferred the decision on whether to proceed with or postpone the launch of the Orbital Sciences’ Cygnus commercial cargo craft until more is known about the flow control valve issue
  • Cygnus is currently scheduled to launch Dec. 18 from Wallops Flight Facility in Virginia and rendezvous with the station on Dec. 21
  • Wednesday, the first of two reboosts of the station took place to raise the station’s orbit and set up
  • for Russian vehicle launches and dockings in 2014
  • also places the station in position for the arrival of Orbital Sciences’ Cygnus commercial cargo vehicle this month
  • e 7-minute, 41-second firing
  • Expedition 38 crew members also tackled a variety of other tasks Thursday, including maintenance work and scientific research
  • work on the Advanced Resistive Exercise Device, or ARED, which allows the crew to perform a wide range of weightlifting exercises in the weightless environment of the station
  • installed a jumper in the Quest airlock to provide contingency power to the airlock’s secondary shell heaters
  • prepared the U.S. spacesuits for some upcoming scheduled maintenance
  • deployed eight bubble detectors for the RaDI-N experiment, which seeks to characterize the neutron radiation environment of the station
  • removed and stowed a NanoRacks platform. NanoRacks provides lower-cost microgravity research facilities for small payloads utilizing a standardized “plug-and-play” interface
  • spoke with students in Kyoto, Japan, via the amateur radio aboard the station
  • unloading cargo from the Progress 53 cargo vehicle that docked to the station on Nov. 29
  • collected micro-accelerometer data for the Identification experiment, which examines the station’s dynamic loads during events such as dockings and reboosts
  • continued the replacement of fans in the Zvezda service module with low-noise units and used a sound level meter to measure the results.
  • conducted routine maintenance on the life support systems in the Zvezda service module
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