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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

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

NASA Hubble Telescope Discovers Water Plumes Over Icy Europa - 0 views

www.scienceworldreport.com/...ter-plumes-over-icy-europa.htm

scibyte113 Europa

shared by Mars Base on 13 Dec 13 - No Cached
  • NASA's Hubble Space Telescope has
  • spotted water vapor above the moon's frigid south polar region, providing the first strong evidence of water plumes erupting off the moon's surface
  • Scientists had previously detected evidence of an ocean under Europa's icy crust
  • ...12 more annotations...
  • the simplest explanation for this water vapor is that it erupted from plumes on the surface of Europa
  • If those plumes are connected with the subsurface water ocean
  • then this means that future investigations can directly investigate the chemical makeup of Europa's potentially habitable environment without drilling through layers of ice
  • This would actually be the second moon in the solar system known to have water vapor plumes
  • The first one to be discovered was Saturn's moon Enceladus
  • First detected in 2005 by NASA's Cassini orbiter, the plumes also possess dust and ice particles
  • So far, though, only water vapor gases have been detected in Europa.
  • It's possible that these plumes could be vented from long cracks on Europa's surface
  • Cassini has actually seen similar fissures that host the Enceladus
  • Europa plumes are similar to Enceladus in another way. They seem to also vary depending on the moon's orbital position; active jets have only been seen when Europa is farthest from Jupiter
  • supports a key prediction that Europa should tidally flex by a significant amount if it has a subsurface ocean
  • Once the plumes are confirmed, scientists can take a closer look at their composition and may even be able to find out more about the potential subsurface sea of Europa
Mars Base

Hubble discovers water vapor venting from Jupiter's moon Europa - 0 views

phys.org/...apor-venting-jupiter-moon.html

scibyte113 Europa

shared by Mars Base on 13 Dec 13 - No Cached
  • Only after a particular camera on the Hubble Space Telescope had been repaired on the last servicing mission by the Space Shuttle did we gain the sensitivity to really search for these plumes
  • Future space probe missions to Europa could confirm that the exact locations and sizes of vents and determine whether they connect to liquid subsurface reservoirs
  • ESA's JUpiter ICy moons Explorer, a mission planned for launch in 2022, and which aims to explore both Jupiter and three of its largest moons: Ganymede, Callisto, and Europa.
Mars Base

China's Maiden Lunar Rover 'Yutu' Rolls 6 Wheels onto the Moon - Photo and Video Gallery - 0 views

www.universetoday.com/...e-moon-photo-and-video-gallery

scibyte113 ChineseSpaceProgram

shared by Mars Base on 15 Dec 13 - No Cached
  • China’s first ever lunar rover rolled
  • onto the Moon’s soil on Sunday, Dec. 15, barely seven hours after the Chang’e-3 mothership touched down
  • The six wheeled ‘Yutu’, or Jade Rabbit, rover drove straight off a pair of ramps at 4:35 a.m. Beijing local time
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
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

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

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

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
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