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Mars Base

Has Dark Matter Been Seen? | Dark Matter and Dark Energy | Space.com - 0 views

www.space.com/rk-matter-detection-wimps.html

scibyte91 DarkMatter

shared by Mars Base on 16 Apr 13 - No Cached
  • absolute zero, which is minus 459.67 degrees Fahrenheit, or minus 273.15 degrees Celsius
  • the signals detected could also be statistical hiccups
  • Scientists would expect to see three or more of these WIMP-like events 5.4 percent of the time simply due to random fluctuations in the experiment
  • ...4 more annotations...
  • But the fluctuations detected by the experiment are in a similar energy range, which is less likely to be a random accident
  • the signal is 99.81 percent more likely to be WIMP than simply background fluctuations, Cabrera said.
  • mass is consistent with earlier CDMS results as well as another dark-matter-hunting experiment called CoGeNT at the U.S. Department of Energy's Pacific Northwest National Laboratory
  • contradicts preliminary results seen at the international XENON Dark Matter Project, a major experiment located in Italy
Mars Base

Dark matter detector reports hints of WIMPs | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/...etector_reports_hints_of_WIMPs

scibyte91 DarkMatter

shared by Mars Base on 16 Apr 13 - No Cached
  • Ultracold crystals designed to catch particles of dark matter deep underground have come up with three potential detections
  • The researchers do not have enough evidence to say they have discovered dark matter particles
  • Theoretical physicists have put forth some ideas for particles that might constitute dark matter, including one called a weakly interacting massive particle, or WIMP.
  • ...22 more annotations...
  • The experiment that made the newly reported detections is designed to pick up the signal of a WIMP as Earth passes through the galaxy
  • The Cryogenic Dark Matter Search consists of a network of silicon and germanium crystals cooled to near absolute zero
  • in the Soudan Underground Laboratory in Minnesota, a former iron mine more than 700 meters beneath the surface
  • If WIMPs exist, one should very occasionally slam into the nucleus of a silicon or germanium atom, causing a release of energy and a detectable vibration in the crystal
  • The hundreds of meters of earth above the experiment prevent other particles, such as protons and neutrons, from reaching the crystals and triggering a false positive
  • between July 2007 and September 2008, two of the experiment’s 11 silicon crystal detectors picked up three signals consistent with those expected from WIMP interactions
  • If the signals were caused by WIMPs
  • estimates the dark matter particle would weigh in at about 10 times the mass of the proton, well below many theoretical estimates
  • While the crystals’ underground setup provides plenty of shielding, some non-WIMP particles, such as electrons on the crystals’ surface, can cloud the results
  • it’s extremely unlikely that three events would show up from non-WIMP sources.
  • the energy released by the potential WIMPs is at the very lower limit of the detectors’ sensitivity
  • making erroneous WIMP detections more likely
  • concerns that the two crystals that picked up the signal could be more susceptible to false positives than the rest
  • In 2009, CDMS published a paper reporting that its germanium detectors had snagged two potential WIMPs, but further analysis revealed them to be surface electrons
  • more convinced if the detectors had picked up 10 or 12 signs of WIMPs, rather than just three
  • definitive detection would require multiple experiments worldwide to converge on the same characteristics for a dark matter particl
  • One in Italy called DAMA, short for Dark Matter, has made bold claims of dark matter detection that have drawn skepticism from many scientists
  • Other experiments have claimed to find signals at masses similar to this latest CDMS calculation but have not definitively said they have observed WIMPs
  • each experiment uses a different detection technique and has its own protocol for distinguishing WIMPs from background noise, making it hard to compare results
  • As for CDMS, the silicon detectors that found these signals are no longer collecting data
  • Researchers recently upgraded the Soudan facility with supersensitive germanium detectors
  • Over the next few years, the germanium detectors will move to a new, deeper underground home in Sudbury, Ontario, about 2 kilometers below the surface
Mars Base

T. K. Mattingly Oral History - 0 views

www.jsc.nasa.gov/...MattinglyTK_11-6-01.htm

scibyte91 Apollo13

shared by Mars Base on 18 Apr 13 - No Cached
  • The Race to the Moon book’s description is probably a little better
  • The way back, the spacecraft started drifting off its trajectory, and now they had to make their midcourse corrections to get back
  • turns out that, too, we had practiced in some simulation somewhere. It’s not very accurate, but it doesn’t have to be
  • ...40 more annotations...
  • It was hard to get people to recognize that we do that, but you don’t need to be the nearest five degrees
  • didn’t solve any problems in the simulator
  • actually ran those procedures, verified them, made some red lines, I think, brought them back over
  • They had to take their flight plan and turn it over and tear out pages and write on the back of it. The only thing they had were pencils and ball pens
  • actually had extra electrical power in the lunar module batteries
  • Somebody came in and found a way to do a jumper cord and take battery power out of the lunar module and top off the command module and to use that power to help get the command module stuff started so we didn’t use all the power from the batteries. So we ended up with a good margin on the batteries
  • Because all our procedures were based on two practical rules. One of them is, structural things don’t break. Actually, that drove everything. Fluid lines and structural—you know, joints can leak, shorts can happen to wires, but physical structure doesn’t break
  • if you admitted to that, then the number of things that you could have to prepare for is infinite.
  • had done a lot of testing of this, a lot of margin of safety in the hardware, so we never looked at those kinds of implications
  • Got in the car to drive back up. This is two days, I think, two days before launch, I think. I’m driving up the road, turned the radio on, and they interrupt the news announcement that this afternoon NASA has announced that they have changed and substituted Jack Swigert for me.
  • Gene says, “Sy, didn’t Jim say that he looked out the window and there’s stuff out in the sky and he heard something?” He says, “Does that sound like instrumentation to you?”
  • thanks to the kind of simulation training program we had, maybe the things weren’t exactly the same or in an exactly the same order, but everything we ended up doing had been done somewhere.
  • somewhere in an earlier sim, there had been an occasion to do what they call LM lifeboat, which meant you had to get the crew out of the command module and into the lunar module, and they stayed there
  • when you get out in space, that all those black spots in between the stars are filled with stars, and those constellations are nowhere near as obvious as they were
  • The guys in the lunar module electrical system had calculated how much time we had, and the two numbers didn’t match. So bringing on this platform is probably the biggest energy user in the spacecraft. Didn’t want to do it
  • They had a capability to maneuver, and they knew where they were, and now they could figure out what to do
  • a big debate about what to do next, as I recall, the books and the movies and all don’t really capture.
  • That debate of what to do next was also rather charged because there was one group of people that said, “You know, this has really been a bad day. We don’t know the condition of any piece of hardware we’ve got. We don’t want to do anything. Don’t touch anything. Let’s just figure this out.”
  • There’s others that said, “There’s only this much electricity and water in the lunar module. We need to turn around and come home as fast as possible.
  • Somewhere in there—I don’t remember all the details—we found out that a family that had gone to a picnic with Charlie and his family over the weekend, one of their kids had the measles, and Charlie was considered exposed
  • One of the many lessons out of all this is starting on day one it was from the very first moment, assume you’re going to succeed and don’t do anything that gets in the way.
  • you had to write down all the numbers in the command module, put them on a list, and then do some math, and then punch the numbers into the lunar module computer
  • you could get a very good alignment so that now you could go in with the lunar module and make a little tweak to tighten up the alignment
  • to get back before the batteries run out
  • while
  • debating what to do with this inertial unit in the command module we had to bring up from scratch, these units are very, very delicate
  • they were allowed to run at a temperature of like 70 plus or minus one. They were tested to see that they would work at plus or minus 10.
  • had one that we don’t know what its temperature is, but we know it’s below freezing
  • didn’t do any testing at those kind of temperatures
  • semi-apocryphal story is that one of the employees at the company
  • had a snowstorm
  • last winter
  • had an IMU in the back of the station wagon
  • took it inside
  • hooked it up and ran it, and they didn’t have any trouble
  • they had had a problem down on the spacecraft, some kind of a problem with detanking the oxygen from the service module
  • took all night and a good bit of the next day
  • to review
  • they’d seen a problem like this before, and even though the regular drain system wasn’t working, they could boil the oxygen out
  • the oxygen tank that we discussed prior to launch was, in fact, the culprit in the explosion. It was damaged in the process that we used in ways that we didn’t anticipate
Mars Base

Mars Science Laboratory: Images - 0 views

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

scibyte91 Curiosity

shared by Mars Base on 21 Apr 13 - No Cached
  • NASA's Curiosity Mars rover targeted the laser of the Chemistry and Camera (ChemCam) instrument with remarkable accuracy for assessing the composition of the wall of a drilled hole and tailings that resulted from the drilling
  • ChemCam fired its laser 150 times (5 bursts of 30 shots, each burst at a different target point) on the drill tailings between the two holes and 300 times (10 bursts of 30 shots) in the drill hole itself
  • The same day, ChemCam's remote micro-imager (RMI) captured images of the laser pits: small craters in the loose tailing
  • ...1 more annotation...
  • and tiny scrapes on the hard surface of the hole walls
  • Mars Base on 21 Apr 13
     
    Accurate pointing by Curiosity
Mars Base

Ken Mattingly Explains How the Apollo 13 Movie Differed From Real Life - 0 views

www.universetoday.com/...-movie-differed-from-real-life

scibyte91 Apollo13

shared by Mars Base on 18 Apr 13 - No Cached
  • : In the movie, mission controllers huddle in a side room and try to figure out how to stretch the resources of the lunar module — designed to carry only two men for a couple of days — into a four-day lifeboat to support three men.
  • somewhat true, NASA already had a preliminary lifeboat procedure simulated
  • Somewhere in an earlier sim [simulation], there had been an occasion to do what they call LM lifeboat, which meant you had to get the crew out of the command module and into the lunar module, and they stayed there
  • ...7 more annotations...
  • In the movie, as the crew faces a deadly buildup of carbon dioxide, a team in mission control builds a new system on the spot that adapts an originally incompatible filter
  • The solution that they came up with was that they could make a way to use the vacuum cleaner in the command module with some plastic bags cut up and taped to the lithium hydroxide cartridges and blow through it with a vacuum cleaner
  • there was a simulation for the Apollo 8 mission where a cabin fan was jammed due to a loose screw
  • Joe [Joseph P.] Kerwin showed up, and we talked about “How did you build that bag and what did you do?”
  • In the movie, Mattingly spends hours in a simulator putting together the procedures for starting up the cold, dead command module in time to bring the astronauts safely back to Earth
  • the simulation runs (done by other astronauts, Mattingly said) were more of a verification of already written procedures
  • they went to the simulator there at JSC [Johnson Space Center], and we handed them these big written procedures and said, “Here. We’re going to call these out to you, and we want you to go through, just like Jack will. We’ll read it up to you. See if there are nomenclatures that we have made confusing or whatever. Just wring it out. See if there’s anything in the process that doesn’t work.”
Mars Base

SkySweeper robot makes inspecting power lines simple and inexpensive (w/ video) - 0 views

phys.org/...-robot-power-lines-simple.html

scibyte91 SkySweeper

shared by Mars Base on 18 Apr 13 - No Cached
  • Mechanical engineers at the University of California
  • invented a robot designed to scoot along utility lines, searching for damage and other problems that require repairs.
  • the SkySweeper prototype could be scaled up for less than $1,000, making it significantly more economical than the two models of robots currently used to inspect power lines
  • ...5 more annotations...
  • Made of off-the-shelf electronics and plastic parts printed on an inexpensive 3D printer
  • Current line inspection robots are large, complex, and expensive
  • Utility companies may also use manned or unmanned helicopters equipped with infrared imaging to inspect lines
  • SkySweeper could be outfitted with induction coils that would harvest energy from the power line itself, making it possible for the robot to stay deployed for weeks or months at a time
  • strengthening the clamps so they can release from the rope and swing down the line, one end to the other, thereby swinging past cable support points
Mars Base

Scientists reverse memory loss in animal brain cells - 0 views

medicalxpress.com/...everse-memory-loss-animal.html

scibyte91 BrainTraining

shared by Mars Base on 18 Apr 13 - No Cached
  • Using sea snail nerve cells, the scientists reversed memory loss by determining when the cells were primed for learning
  • scientists were able to help the cells compensate for memory loss by retraining them through the use of optimized training schedules
  • study builds on
  • ...19 more annotations...
  • 2012 investigation that pioneered this memory enhancement strategy
  • The 2012 study showed a significant increase in long-term memory in healthy sea snails
  • study's co-lead author and a research scientist
  • has developed a sophisticated mathematical model that can predict when the biochemical processes in the snail's brain are primed for learning
  • model is based on five training sessions scheduled at different time intervals ranging from 5 to 50 minutes
  • can generate 10,000 different schedules and identify the schedule most attuned to optimum learning
  • Memory is due to a change in the strength of the connections among neurons. In many diseases associated with memory deficits, the change is blocked
  • senior research scientist
  • simulated a brain disorder in a cell culture by taking sensory cells from the sea snails and blocking the activity of a gene that produces a memory protein
  • This resulted in a significant impairment in the strength of the neurons' connections, which is responsible for long-term memory
  • To mimic training sessions, cells were administered a chemical at intervals prescribed by the mathematical model
  • After five training sessions, which like the earlier study were at irregular intervals, the strength of the connections returned to near normal in the impaired cells
  • This methodology may apply to humans if we can identify the same biochemical processes in humans
  • results suggest a new strategy for treatments of cognitive impairment
  • Mathematical models might help design therapies that optimize the combination of training protocols with traditional drug treatments
  • Combining these two could enhance
  • effectiveness
  • while compensating at least in part for any limitations or undesirable side effects of drugs
  • two approaches are likely to be more effective together than separately and may have broad generalities in treating individuals with learning and memory deficits."
Mars Base

Virgin Galactic 8 5min video - YouTube - 0 views

www.youtube.com/watch

scibyte91 VirginGalactic

shared by Mars Base on 20 Apr 13 - No Cached
  • Mars Base on 20 Apr 13
     
    Virgin Galactic 8 5min video
Mars Base

SkySweeper Robot Makes Inspecting Power Lines Simple and Inexpensive - YouTube - 0 views

www.youtube.com/watch

scibyte91 SkySweeper

shared by Mars Base on 20 Apr 13 - No Cached
  • Mars Base on 20 Apr 13
     
    SkySweeper Robot Makes Inspecting Power Lines Simple and Inexpensive
Mars Base

Most Earthlike planets yet seen bring Kepler closer to its holy grail | Atom & Cosmos |... - 0 views

www.sciencenews.org/...epler_closer_to_its_holy_grail

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • five-planet system around a star called Kepler-62, some 1,200 light-years away in the constellation Lyra
  • Astronomers found the planets by analyzing nearly three years’ worth of data
  • Kepler-62e and Kepler-62f are far more accommodating. They are 1.6 and 1.4 times the diameter of Earth
  • ...19 more annotations...
  • early evidence supports the optimistic view that at least 62f is rocky
  • biggest uncertainty about both planets is their composition
  • an astronomer at the University of Washington
  • not involved in the research
  • Kepler-62e
  • may be too close to its star – and therefore too hot – to sustain life
  • if 62e is a rocky planet, it’s almost certainly tidally locked with its star, with one half of its surface always illuminated and the other perpetually dark
  • Kepler 62 is about two-thirds the size of the sun and several hundred degrees Celsius cooler
  • Finding planets in the habitable zones of larger stars
  • harder because those planets have relatively long orbits and barely cast a shadow as they pass across the faces of their suns
  • another study
  • led by
  • NASA Ames Research Center
  • identified two planets around a sunlike star called Kepler-69, some 2,700 light-years away
  • One of the planets is 1.7 times the size of Earth and teeters on the inner edge of the habitable zone
  • probably too hot for life
  • almost certainly a super-Venus rather than a super-Earth
  • even a planet 75 percent larger than Earth is potentially habitable
  • Next-generation missions like the Transiting Exoplanet Survey Satellite, which NASA approved earlier this month for launch in 2017, will take on the task of finding nearer planets that astronomers can study in depth
Mars Base

3 Potentially Habitable Super-Earth Planets Explained (Infographic) | Space.com - 0 views

www.space.com/abitable-zone-infographic.html

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • Kepler-62 is a red dwarf, only 20 percent as bright as the sun
  • located 1,200 light-years away from Earth
  • The Kepler-69 system contains one known planet in that star's habitable zone
  • ...3 more annotations...
  • a sun-like star located 2,700 light-years away,
  • As of April 2013, Kepler data has uncovered more than 2,700 potential planets, with about 120 of them having been confirmed to date
  • mission scientists expect that more than 90 percent of the planets detected are real and not illusions in the data
Mars Base

Discovered! Most Earth-Like Alien Planet & 2 Other Possibly Habitable Worlds | Space.com - 0 views

www.space.com/e-alien-planets-discovery.html

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • The third potentially habitable planet, called Kepler-69c, is 1.7 times bigger than Earth and orbits a star similar to our own
  • It's the smallest world ever found in the habitable zone of a sunlike star
  • scientists rolled out seven new exoplanets today — five in the Kepler-62 system and two in Kepler-69
  • ...3 more annotations...
  • Kepler-62e and f take 122 and 267 days, respectively, to complete one orbit around their star, which is just 20 percent as bright as the sun
  • The telescope needs to observe three transits to flag a planet candidate, so detecting a potentially habitable world in a relatively distant orbit can take several years
  • Kepler cannot search for signs of life on worlds like Kepler-62e, Kepler-62f and Kepler-69c, but the telescope is paving the way for future missions that should do just that
Mars Base

The Solar Cell That Turns 1 Photon into 2 Electrons: Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte91 solarcell

shared by Mars Base on 19 Apr 13 - No Cached
  • If an incoming photon has too little energy, the cell won’t absorb it
  • Solar cells
  • If a photon has too much, the excess is wasted as heat
  • ...8 more annotations...
  • a silicon solar cell can never generate more than one electron from a single photon
  • severely limit the conversion efficiency of photovoltaic cells, and scientists have spent decades looking for work-arounds
  • the key to greater solar efficiency might be an organic dye called pentacene
  • a photovoltaic cell based on pentacene can generate two electrons from a single photon—more electricity from the same amount of sun.
  • The key is a phenomenon called singlet-exciton fission, in which an arriving photon generates two “excitons” (excited states) that can be made to yield two electrons.
  • Previous researchers had accomplished similar tricks using quantum dots (tiny pieces of matter that behave like atoms) and deep-ultraviolet light
  • Why it works is still not particularly clear, and for now, the pentacene cell works only with an extremely narrow band of visible light
  • it should be possible to create a pentacene coating for silicon solar cells that boosts the total conversion efficiency from today’s 25 percent to a shade over 30 percent—a significant jump
Mars Base

Astronomers Hint that our Sun won't Terminate as the Typical Planetary Nebula - 0 views

www.universetoday.com/...s-the-typical-planetary-nebula

scibyte91 sun

shared by Mars Base on 19 Apr 13 - No Cached
  • Textbooks often cite that planetary nebulae (PNe, plural) represent an endstate for lower-mass single stars
  • recent research suggests that most PNe stem from binary systems
  • The lowest mass star theorized to form the typical PN is near 1 solar mass, and thus without a companion the Sun may not surpass the mass limit required to generate the hot glowing (ionized) nebula typically tied to PNe
  • ...5 more annotations...
  • New research continues to question our original understanding of how the Sun’s life may end.
  • while the binary interaction model explains some of the anomalies associated with the observed planetary nebula population, this theory awaits final confirmation
  • The traditional theory
  • does not provide a natural explanation for the non-spherical
  • observed for the great majority
Mars Base

Kepler Team Finds System with Two Potentially Habitable Planets - 0 views

www.universetoday.com/...-potentially-habitable-planets

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • scientists analyzing data from NASA’s Kepler mission has found a planetary system with two small, potentially rocky planets that lie within the habitable zone of their star
  • Kepler-62, is a bit smaller and cooler than our Sun, and is home to a five-planet system
  • Two of the worlds, Kepler-62e and Kepler-62f are the smallest exoplanets yet found in a habitable zone, and they might both be covered in water or ice, depending on what kind of atmosphere they might have
  • ...19 more annotations...
  • The curves show the mass-radius-relation (average density) for different types of planets
  • The blue line indicates
  • planets made mostly (75%) of water, the black line that of planets like our Earth that consist almost exclusively of rock (
  • estimate of their mass places them in a region (blue areas) where it is highly probable for them to be earth-like planets, that is: planets with a solid (if possibly covered in water) surface
  • the empirical habitable zone, liquid water can exist on the surface of a planet if that planet has sufficient cloud cover. In the narrow habitable zone, liquid water can exist on the surface even without the presence of a cloud cover
  • while the sizes of Kepler 62e and 62f are known, their mass and densities are not.
  • every planet found in their size range so far has been rocky, like Earth
  • Life on these worlds would be under water with no easy access to metals, to electricity, or fire for metallurgy
  • life’s inventiveness to get to a technology stage will surprise us
  • Kepler-62e would have a bit more clouds than Earth according to computer models
  • More distant Kepler-62f would need the greenhouse effect from plenty of carbon dioxide to warm it enough to host an ocean
  • Kepler-62e probably has a very cloudy sky and is warm and humid all the way to the polar regions
  • Kepler-62f would be cooler, but still potentially life-friendly
  • the two would exhibit distinctly different colors and make our search for signatures of life easier on such planets in the near future
  • planets in the habitable zone were until now discovered by what is known as the radial velocity method
  • gives you a lower limit for the planet’s mass, but no information about its radius
  • What makes Kepler-62e and Kepler-62f so exciting is
  • We know their radius, which indicates that these are indeed rocky planets, and they orbit their star in the habitable zone
  • makes it difficult to assess whether or not a planet is rocky, like the Earth. A small radius (less than 2 Earth radii), on the other hand, is a strong indicator that a planet around is indeed rocky – unless we are talking about a planet around a very young star
Mars Base

Habitable Worlds? New Kepler Planetary Systems in Images - 0 views

www.universetoday.com/...er-planetary-systems-in-images

scibyte91 scibyte92 exoplanet

shared by Mars Base on 19 Apr 13 - No Cached
  • According to the Planetary Habitability Laboratory, there are now nine potential habitable worlds outside of our solar system, with 18 more potentally habitable planetary candidates found by Kepler waiting to be confirmed
  • astronomers predict there are 25 potentially habitable exomoons
  • Current known potentially habitable exoplanets. Credit: Planetary Habitability Laboratory/University of Puerto Rico, Arecibo
Mars Base

Virgin Galactic's SpaceShipTwo Makes Stunning Leap Toward Private Spaceflight | Space.com - 0 views

www.space.com/rgin-galactic-test-flight.html

scibyte91 VirginGalactic

shared by Mars Base on 17 Apr 13 - No Cached
  • Virgin Galactic's suborbital SpaceShipTwo successfully conducted its first "cold flow" flight test above the Mojave Desert
  • April 12).
  • During the test, oxidizer was run through the rocket's propulsion system and out the back nozzle of the ship, though the vehicle's rocket engine was not turned on
  • ...6 more annotations...
  • The next big step for the commercial spaceflight company appears to be conducting a full flight test, igniting the rocket in the air.
  • Once SpaceShipTwo is operational, WhiteKnightTwo will carry the vehicle up to an altitude of about 50,000 feet (15,240 meters) before releasing it.
  • After separation, SpaceShipTwo will accelerate to 2,500 mph (4,000 km/h) and eventually pass an altitude of 62 miles (100 kilometers), the point at which passengers are considered astronauts
  • The spaceship will reach a peak altitude of 68 miles (110 km), giving the six passengers and two pilots about five minutes of weightlessness
  • Upon re-entry, SpaceShipTwo will be able to land on a conventional runway
  • A seat on board a SpaceShipTwo flight costs $200,000. More than 550 people have put down deposits to reserve a spot
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