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Mars Base

Curiosity Hammers into Mars Rock in Historic Feat - 0 views

www.universetoday.com/...nto-mars-rock-in-historic-feat

scibyte80 Curiosity

shared by Mars Base on 05 Feb 13 - No Cached
  • Image caption: Curiosity tool turret located at end of robotic arm is positioned with drill bit
  • on Jan 31, 2013
  • The Alpha Particle X-Ray Spectrometer (APXS) was also placed in contact with the ground to determine the chemical composition of the rock drill test site and possible calcium sulfate vein and investigate its hydration state.
  • ...3 more annotations...
  • Image caption: Close-up view of Curiosity drill bit penetrating John Klein outcrop
  • Curiosity can drill to a depth of about 2 inches (5 cm) into rocks
  • Ultimately a powdered and sieved sample about half an aspirin tablet in size will be delivered to the SAM and CheMin analytical labs on the rover deck.
Mars Base

Mars Science Laboratory: Images - 0 views

mars.jpl.nasa.gov/...images

scibyte80 Curiosity

shared by Mars Base on 05 Feb 13 - No Cached
  • Drill Bit Tip on Mars Rover Curiosity, Side View
Mars Base

Mars Science Laboratory: Images - 0 views

mars.jpl.nasa.gov/...images

scibyte80 Curiosity

shared by Mars Base on 05 Feb 13 - No Cached
  • The bit in the rotary-percussion drill of NASA's Mars rover Curiosity left its mark in a target patch of rock
  • (Feb. 2, 2013
  • used only the hammering or percussive action of the drill, not rotary action.
  • ...5 more annotations...
  • This image
  • was taken with the camera positioned about 4 inches (10 centimeters) off the ground
  • about 3 inches (7.7 centimeters) wide. The length of the gray divot cut by the drill bit is about two-thirds of an inch (1.7 centimeters)
  • Another preparatory test, called "mini drill," will precede the full drilling
  • The mini drill test will use both the rotary and percussive actions of the drill to generate a ring of rock powder around a hole
Mars Base

Mars Science Laboratory: Images - 0 views

mars.jpl.nasa.gov/...images

scibyte80 Curiosity

shared by Mars Base on 05 Feb 13 - No Cached
  • Drill Bit Tip on Mars Rover Curiosity, Head-on View
Mars Base

Mars Science Laboratory: Weekend Test on Mars Was Preparation to Drill a Rock - 0 views

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

scibyte80 Curiosity

shared by Mars Base on 05 Feb 13 - No Cached
  • The successful activity, called a "drill-on-rock checkout" by the rover team at NASA's Jet Propulsion Laboratory, Pasadena, is part of a series of tests to prepare for the first drilling in history to collect a sample of rock material on Mars
  • Another preparatory test, called "mini drill," will precede the full drilling
  • The mini drill test will use both the rotary and percussive actions of the drill to generate a ring of rock powder around a hole
  • ...1 more annotation...
  • This will allow for evaluation of the material to see if it behaves as a dry powder suitable for processing by the rover's sample handling mechanisms
Mars Base

First Evidence of Life in Antarctic Subglacial Lake : The Crux - 0 views

blogs.discovermagazine.com/...e-in-antarctic-subglacial-lake

scibyte80 AntarcticLake

shared by Mars Base on 01 Feb 13 - No Cached
  • The search continues for life in subglacial Lake Whillans, 2,600 feet below the surface of the West Antarctic Ice Sheet—but a thrilling preliminary result has detected signs of life
  • At 6:20am on January 28, four people in sterile white Tyvek suits tended to a winch winding cable onto the drill platform
  • One person knocked frost off the cable as it emerged from the ice borehole a few feet below
  • ...24 more annotations...
  • a gray plastic vessel, as long as a baseball bat, filled with water from Lake Whillans, half a mile below.
  • The bottle was hurried into a 40-foot cargo container outfitted as a laboratory on skis
  • Some of the lake water was squirted into bottles of media in order to grow whatever microbes might inhabit the lake
  • cultures could require weeks to produce results
  • When lake water was viewed under a microscope, cells were seen: their tiny bodies glowed green in response to DNA-sensitive dye. It was the first evidence of life in an Antarctic subglacial lake.
  • (A Russian team has reported that two types of bacteria were found in water from subglacial Lake Vostok, but DNA sequences matched those of bacteria that are known to live inside kerosene—causing the scientists to conclude that those bacteria came from kerosene drilling fluid used to bore the hole, and not from Lake Vostok itself
  • In order to conclusively demonstrate that Lake Whillans harbors life, the researchers will need to complete more time-consuming experiments showing that the cells actually grow
  • dead cells can sometimes show up under a microscope with DNA-sensitive
  • weeks or months will pass before it is known whether these cells represent known types of microbes, or something never seen before
  • t a couple of things seem likely. Most of those microbes probably subsist by chewing on rocks. And despite being sealed beneath 2,600 feet of ice, they probably have a steady supply of oxygen.
  • oxygen comes from water melting off the base of the ice sheet—maybe a few penny thicknesses of ice per year
  • When you melt ice, you’re liberating the air bubbles [trapped in that ice
  • That’s 20 percent oxygen
  • , lake bacteria could live on commonly occurring pyrite minerals that contain iron and sulfur
  • would obtain energy by using oxygen to essentially “burn” that iron and sulfur (analogous to the way that animals use oxygen to slowly burn sugars and fats).
  • The half mile of glacial ice sitting atop Lake Whillans is quite pure—derived from snow that fell onto Antarctica thousands of years ago.
  • contains only one-hundredth the level of dissolved minerals that are seen in a clear mountain creek, or in tap water from a typical city
  • a sensor lowered down the borehole this week showed that dissolved minerals were far more abundant in the lake itself
  • The fact that we see high concentrations is suggestive that there’s some interesting water-rock-microbe interaction that’s going on
  • Microbes, in other words, might well be munching on minerals under the ice sheet
  • will take months or years to unravel this picture
  • will perform experiments to see whether microbes taken from the lake metabolize iron, sulfur, or other components of minerals
  • will analyze the DNA of those microbes to see whether they’re related to rock-chewing bacteria that are already known to science.
  • Antarctica isn’t the only place in the solar system where water sits concealed in the dark beneath thick ice. Europa and Enceladus (moons of Jupiter and Saturn, respectively) are also thought to harbor oceans of liquid water. What is learned at Lake Whillans could shed light on how best to look for life in these other places
Mars Base

Chipmaker Races to Save Stephen Hawking's Speech as His Condition Deteriorates: Sc... - 0 views

www.scientificamerican.com/article.cfm

scibyte80 StephenHawking

shared by Mars Base on 01 Feb 13 - No Cached
  • Renowned physicist Stephen Hawking has long relied on technology to help him connect with the outside world despite the degenerative motor neuron disease he has battled for the past 50 years
  • a highly respected computer scientist indicated at last week’s International Consumer Electronics Show (CES) that he and his team may be close to a breakthrough that could boost the rate at which the physicist communicates, which has fallen to a mere one word per minute in recent years.
  • For the past decade Hawking has used a voluntary twitch of his cheek muscle to compose words and sentences one letter at a time that are expressed through a speech-generation device connected to his computer.
  • ...25 more annotations...
  • Each tweak stops a cursor that continuously scans text on a screen facing the scientist.
  • Intel chief technology officer
  • noted that Hawking can actually make a number of other facial expressions as well that might also be used to speed up the rate at which the physicist conveys his thoughts
  • Even providing Hawking with two inputs would give him the ability to communicate using Morse code
  • Intel has since the late 1990s supplied Hawking with technology to help the scientist express himself
  • The latest chapter in their work together began in late 2011 when Hawking reached out to
  • inform
  • the Intel co-founder and father of Moore’s law that the physicist’s ability to compose text was slowing and inquiring whether Intel could help.
  • met with Hawking early last year around the time of the latter’s 70th birthday celebration in Cambridge, where the Intel CTO was one of the speakers
  • After meeting with Hawking
  • he wondered whether his company’s processor technology could restore the scientist’s ability to communicate at five words per minute, or even increase that rate to 10
  • Intel is now working on a system that can use Hawking’s cheek twitch as well as mouth and eyebrow movements to provide signals to his computer
  • built a new, character-driven interface in modern terms that includes a better word predictor
  • company is also exploring the use of facial-recognition software to create a new user interface for Hawking that would be quicker than selecting individual letters or words
  • A black box beneath his wheelchair contains an audio amplifier, voltage regulators and a USB hardware key that receives the input from an infrared sensor on Hawking’s eyeglasses, which detects changes in light as he twitches his cheek
  • current setup includes a tablet PC with a forward-facing Webcam that he can use to place Skype calls
  • A hardware voice synthesizer sits in another black box on the back of the chair and receives commands from the computer via a USB-based serial port
  • Intel’s work with Hawking is part of the company’s broader research into smart gadgets as well as assistive technologies for the elderly
  • The key to advancing smart devices—which have been at a plateau over the past five or six years—is context awareness
  • Devices will really get to know us the way a friend would, understanding how our facial expressions reflect our mood
  • Intel’s plan for identifying personal context requires a combination of hardware sensors—camera, accelerometer, microphone, thermometer and others
  • with software that can check one’s personal calendar, social networks and Internet browsing habits, to name a few.
  • use this [information] to reason your current context and what's important at any given time [and deliver] pervasive assistance
  • One approach to “pervasive assistance” is the Magic Carpet, a rug that Intel and GE developed with embedded sensors and accelerometers that can record a person’s normal routine and even their gait, sounding an alert when deviations are detected.
  • Such assistance will anticipate our needs, letting us know when we are supposed to be at an appointment and even reminding us to carry enough cash when running certain errands
Mars Base

Study of friction reveals clues about arthritis - 0 views

phys.org/...n-reveals-clues-arthritis.html

scibyte80 arthritis

shared by Mars Base on 30 Jan 13 - No Cached
  • A new, noninvasive, and low-cost method for the early detection and monitoring of osteoarthritis (arthritis caused by wear and tear) may be on its way
  • By studying patterns of friction between cartilage pads, the researchers discovered a different type of friction that is more likely to cause wear and damage
  • work suggests ways to detect this friction, and points to new research directions for getting to the root cause of arthritis
  • ...31 more annotations...
  • Imagine going to the doctor for your aching knees
  • what if your doctor could actually listen to your body, monitoring the way your knees sound as they bend and flex
  • an instrument called a Surface Forces Apparatus (SFA), a device that measures the adhesion and friction forces between surfaces—in this case cartilage, the pad of tissue that covers the ends of bones at a joint.
  • degeneration of cartilage is the most common cause of osteoarthritis: The pads wear away, leaving bone grinding against bone
  • researchers found is that it isn't just any kind of friction that leads to the irreversible wear and tear on the material
  • currently believed that a high-friction force, or 'coefficient of friction,' is the primary factor in surface wear and damage
  • found is that this is not the case
  • The critical feature is not a high-friction force, but what is known as "stick-slip" friction, or, sometimes, "stiction."
  • Both are characterized by surfaces that initially stick together, and then accelerate away quickly once the static friction force is overcome
  • With stick-slip friction, the surfaces eventually pull slightly apart and slide across each other, stick again, and pull apart, causing jerky movements.
  • That's when things get damaged microscopically
  • Stick-slip is a common phenomenon. It is responsible for everything from computer hard drive crashes and automobile failures, to squeaking doors and music
  • same thing happens with a violin string
  • Even if you're pulling the bow steadily, it's moving in hundreds or thousands of little jerks per second, which determine the sound you hear
  • Each little jerk, no matter how submicroscopic, is an impact, and over time the accumulation of these impacts can deform surfaces, causing irreparable damage—first microscopically, then growing to macroscopic
  • it's not easy to tell the difference between types of friction at the microscopic level
  • Smooth-sliding joints might feel the same as those undergoing stiction, or the even more harmful stick-slip, especially in the early stages of arthritis
  • when measured with an ultra-sensitive and high-resolution instrument like the SFA, each type of friction revealed its own characteristic profile
  • Smooth-sliding joints yielded an almost smooth constant line (friction force or friction trace
  • with stiction showed up as a peak, as the "sticking" was being overcome, followed by a relatively smooth line
  • stick-slip shows the jagged saw-tooth profile of two surfaces repeatedly pulling apart, sticking, and pulling apart again
  • these measurements could be recorded by placing an acoustic or electric sensing device around joints, giving a signal similar to an EKG.
  • this could be a good way to measure and diagnose damage to the cartilage
  • to measure the progression, or even the early detection of symptoms related to arthritis
  • Early detection of conditions like arthritis has been a priority for many years
  • the functioning of joints is more complicated
  • scientists will continue their work by studying synovial fluid—the lubricating fluid between two cartilage surfaces in joints
  • plays a major role in whether or not the surfaces wear and tear, and the synergistic roles of the different molecules (proteins, lipids, and polymers
  • all involved in lubricating and preventing damage to our joints.
  • a number of directions to take, both fundamental and practical
  • it looks as if we need to focus our research on finding ways to prevent stick-slip motion, rather than lowering the friction force
Mars Base

Working alone won't get you good grades, study finds - 0 views

phys.org/...2013-01-wont-good-grades.html

scibyte80 Learning

shared by Mars Base on 01 Feb 13 - No Cached
  • Students who work together and interact online are more likely to be successful in their college classes, according to a study
  • 80,000 interactions between 290 students in a collaborative learning environment for college courses
  • major finding was that a higher number of online interactions was usually an indicator of a higher score in the class
  • ...12 more annotations...
  • High achievers also were more likely to form strong connections with other students and to exchange information in more complex ways
  • tended to form cliques, shutting out low-performing students from their interactions
  • Students who found themselves shut out were not only more likely to have lower grades; they were also more likely to drop out of the class entirely.
  • Elite groups of highly connected individuals formed in the first days of the course
  • "For the first time, we showed that there is a very strong correspondence between social interaction and exchange of information - a 72 percent correlation
  • almost equally interesting is the fact that these high-performing students form 'rich-clubs', which shield themselves from low-performing students, despite the significant efforts by these lower-ranking students to join them.
  • weaker students try hard to engage with the elite group intensively, but can't. This ends up having a marked correlation with their dropout rates
  • might better identify patterns in the classroom that can trigger early dropout alarms
  • allowing more time for educators to help the student and, ideally, reduce those rates through appropriate social network interventions.
  • work is part of
  • wider research effort at the intersection of the computer and social sciences
  • enhance our understanding of the ways in which people share information and how this impacts areas of national significance, such as the spread of health-related or political behavior.
Mars Base

Historic First Use of Drill on Mars Set for Jan. 31 - Curiosity's Sol 174 - 0 views

www.universetoday.com/...-for-jan-31-curiositys-sol-174

scibyte80 Curiosity

shared by Mars Base on 01 Feb 13 - No Cached
  • Curiosity drove about 3.5 meters to reach the John Klein outcrop that the team chose as the 1st drilling site. The car sized rover is investigating a shallow depression known as ‘Yellowknife Bay’
  • widespread evidence for repeated episodes of the ancient flow of liquid water near her landing site inside Gale Crater on Mars.
Mars Base

Mars Science Laboratory: Curiosity Maneuver Prepares for Drilling - 0 views

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

scibyte70 Curiosity

shared by Mars Base on 01 Feb 13 - No Cached
  • placed its drill onto a series of four locations on a Martian rock and pressed down on it with the rover's arm, in preparation for using the drill in coming days.
  • carried out this "pre-load" testing on Mars
  • (Jan. 27
  • ...15 more annotations...
  • ctions for what would result from the commanded motions.
  • next step is an overnight pre-load test, to gain assurance that the large temperature change from day to night at the rover's location does not add excessively to stress on the arm while it is pressing on the drill
  • air temperature plunges from about 32 degrees Fahrenheit (zero degrees Celsius) in the afternoon to minus 85 degrees Fahrenheit (minus 65 degrees Celsius) overnight
  • Over this temperature swing, this large rover's arm, chassis and mobility system grow and shrink by about a tenth of an inch (about 2.4 millimeters), a little more than the thickness of a U.S. quarter-dollar coin
  • Remaining preparatory steps will take at least the rest of this week
  • Some of these steps are hardware checks. Others will evaluate characteristics of the rock material at the selected drilling site on a patch of flat, veined rock called "John Klein
  • We are proceeding with caution in the approach to Curiosity's first drilling. This is challenging. It will be the first time any robot has drilled into a rock to collect a sample on Mar
  • "drill-on-rock checkout" will use the hammering action of Curiosity's drill briefly, without rotation of the drill bit, for assurance that the back-and-forth percussion mechanism and associated control system are properly tuned for hitting a rock
  • the surface of the rock while penetrating less than eight-tenths of an inch (2 centimeters).
  • "mini-drill" is designed to produce a small ring of tailings -- powder resulting from drilling
  • will not go deep enough to push rock powder into the drill's sample-gathering chamber
  • The rover team's activities this week are affected by the difference between Mars time and Earth time
  • To compensate for this, the team develops commands based on rover activities from two sols earlier
  • the mini-drill activity cannot occur sooner than two sols after the drill-on-rock checkout.
  • Martian sol lasts about 40 minutes longer than a 24-hour Earth day.
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