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Mars Base

Nearby Ancient Star is Almost as Old as the Universe - 0 views

www.universetoday.com/...-almost-as-old-as-the-universe

scibyte84

shared by Mars Base on 24 Feb 13 - No Cached
  • A metal-poor star located merely 190 light-years from the Sun is 14.46+-0.80 billion years old, which implies that the star is nearly as old as the Universe
  • results emerged from a new study
  • Such metal-poor stars are (super) important to astronomers because they set an independent lower limit for the age of the Universe
  • ...21 more annotations...
  • can be used to corroborate age estimates inferred by other means
  • In the past, analyses of globular clusters and the Hubble constant
  • yielded vastly different ages for the Universe, and were offset by billions of years
  • based on the microwave background and Hubble constant, but it must have formed soon after the big bang
  • Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 ± 0.06 billion years
  • Metal-poor stars can be used to constrain the age of the Universe because metal-content is typically a proxy for age
  • Heavier metals are generally formed in supernova explosions, which pollute the surrounding interstellar medium.
  • Stars subsequently born from that medium are more enriched with metals than their predecessors
  • each successive generation becoming increasingly enriched
  • HD 140283 exhibits less than 1% the iron content of the Sun, which provides an indication of its sizable age.
  • had been used previously to constrain the age of the Universe, but uncertainties tied to its estimated distance (at that time) made the age determination somewhat imprecise
  • obtain a new and improved distance for HD 140283 using the Hubble Space Telescope (HST), namely via the trigonometric parallax approach
  • distance uncertainty for HD 140283 was significantly reduced by comparison to existing estimates, thus resulting in a more precise age estimate for the star
  • The reliability of the age determined is likewise contingent on accurately determining the sample’s metal content
  • analyses of globular clusters and the Hubble constant yielded vastly different ages for the Universe
  • discrepant ages stemmed partly from uncertainties in the cosmic distance scale
  • determination of the Hubble constant relied on establishing (accurate) distances to galaxies
  • One of the key objectives envisioned for HST was to reduce uncertainties associated with the Hubble constant to <10%, thus providing an improved estimate for the age of the Universe
  • the mean implying an age near ~14 billion years
  • Determining a reliable age for stars in globular clusters is likewise contingent on the availability of a reliable distance
  • the study reaffirms that there are old stars roaming the solar neighborhood which can be used to constrain the age of the Universe
Mars Base

Japanese Team Claims Discovery Of Elusive Element 113, And May Get To Name It | Popular... - 0 views

www.popsci.com/...lement-113-and-may-get-name-it

scibyte65 elements

shared by Mars Base on 30 Sep 12 - No Cached
  • Japanese researchers claim they’ve seen conclusive evidence of the long-sought element 113, a super-heavy, super-unstable element near the bottom of the periodic table
  • not yet verified by the International Union of Pure and Applied Chemistry
  • if the IUPAC grants its blessing, the researchers could be the first team from Asia to name one of nature’s fundamental atoms.
  • ...5 more annotations...
  • Super-heavy elements do not occur in nature and have to be discovered in the lab, using particle accelerators, nuclear reactors, ion separators and other complex equipment
  • Science have been hunting for 113 for nine years, and have claimed to see it a few times already — but the evidence has never been this clear,
  • the team used a customized gas-filled recoil ion separator paired with a semiconductor detector that can pick out atomic reaction products
  • created element 113 by speeding zinc ions through a linear accelerator until they reached 10 percent of the speed of light.
  • ions then smashed into a piece of bismuth. When the zinc and bismuth atoms fused, they produced an atom with 113 protons
Mars Base

Could the Next Planetary Rover Come from Canada? - 0 views

www.universetoday.com/...anetary-rover-come-from-canada

scibyte70 rover

shared by Mars Base on 29 Oct 12 - No Cached
  • Canadian Space Agency is well known for its robotics but they’ve recently expanded from robotic arms to building prototypes for five new rovers, designed for future lunar and Mars missions
  • range from microrovers to full-sized science missions and range in size from 30 kg up to 900 kg.
  • the Lunar Exploration Light Rover, is designed to carry a scientific payload and can be fitted with a robotic arm. It has a range of 15 km, can be operated remotely, or can be used to carry astronauts across a planetary surface.
  • ...14 more annotations...
  • two Micro-Rover prototypes, at 40 kg and 30 kg., are designed to be operated in conjunction with larger rovers, and can be tethered to them and lowered into otherwise inaccessible areas.
  • On the Moon, permanently shadowed craters provide many interesting areas to find water and other volatiles
  • craters have steep slopes making it difficult and risky for a large rover
  • sending a micro-rover tethered to its mother one gives us the ability to explore the bottom of these craters with a minimum risk.
  • they are very slow so it is more efficient to have them on a larger rover to cover long distance and deploy them when needed.
  • The micro-rovers can also be used to work alongside astronauts, to gain access to small spaces like caves
  • e rovers should be mission-ready by about 2020, and NASA is already interested.
  • designs are intended to fit in with those types of activities.
  • NASA has an experiment under consideration that entails digging up soil on the Moon and making hydrogen and oxygen out of it
  • Canadarm was a fixture on the Space Shuttles and made it possible to do things like deploying satellites like the Hubble Space Telescope
  • instrumental in building the International Space Station
  • CSA also built the huge Canadarm 2 and Dextre, the highly dexterous dual-armed robot, both of which reside on the International Space Station
  • CSA contributed a robotic arm and other equipment to Curiosity
  • e CSA doesn’t anticipate any other rover designs, these 5 prototypes could be focused “on more specific applications such as in-situ resource utilization or science,
Mars Base

How Supersonic Skydiver Will Freefall Through Earth's Atmosphere | Felix Baumgartner Sp... - 0 views

www.space.com/-skydive-earth-atmosphere.html

scibyte66 RedBullStratos

shared by Mars Base on 06 Oct 12 - No Cached
  • Earth's atmosphere starts 430 miles (690 kilometers) up.
  • upper boundary of the thermosphere, the outermost layer of the atmosphere
  • Solar radiation bombards this layer, striking its sparse air molecules and causing them to emit flashes of light: the auroras
  • ...6 more annotations...
  • altitude of 53 miles (85 km), the thermosphere transitions into the mesosphere, an atmospheric layer known for its faint clouds, as well as electrical discharge events called red sprites and blue jets.
  • e stratosphere extends from an altitude of 6 miles (10 kilometers) up to about 30 miles (50 km) above the surface. The air pressure drops from 10 percent of its value at sea level to just 0.1 percent
  • , unlike in the layers above and below, absorption of ultraviolet sunlight by ozone causes the temperature to increase as you move up in altitude
  • coupling of temperature with altitude prevents convection from happening, and so the air in this layer is dynamically stable.
  • troposphere, which includes everything from an altitude of 6 miles down over most of Eart
  • re all weather happens, as well as longer-term processes such as the jet stream. In this layer, temperature and pressure both drop as you move up in altitude
Mars Base

Meteorite From California Fireball Is Meteor-wrong, Scientist Says | Space.com - 0 views

www.space.com/all-meteorite-normal-rock.html

scibyte69 meteor

shared by Mars Base on 26 Oct 12 - No Cached
  • A rock thought to be a meteorite from a recent fireball seen over Northern California is in fact, just a regular Earth rock
  • Projected band (light area) where meteorites of different size may have fallen over Marin and Sonoma counties from an Oct. 17, 2012 meteor.
  • Novato, Calif. resident
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  • read about the fireball and recalled hearing a sound on her roof that night
  • she and neighbors found a ding on the roof
  • On closer inspection, that crust was a product of weathering of a natural rock, not from the heat of entry
  • Examination of the rock under a petrographic microscope quickly revealed the stone was not a meteorite
  • the ding on Webber's roof, along with her recollection of the sound she heard that night, suggest her house may in fact have been hit by a still-missing meteorite.
  • r Marin and Sonoma counties
Mars Base

Ancient Quasar Shines Brightly, But All the Galaxy's Stars Are Missing - 0 views

www.universetoday.com/...-the-galaxys-stars-are-missing

scibyte69 quasar

shared by Mars Base on 24 Oct 12 - No Cached
  • Quasars have been the best and most easily observed beacons for astronomers to probe the distant Universe
  • one of the most distant and brightest quasars is providing a bit of a surprise
  • Astronomers studying a distant galaxy, dubbed J1148+5251 and which contains a bright quasar, are seeing only the quasar and not the host galaxy itself
  • ...15 more annotations...
  • has been thought that the quasar has been feeding on a handful of stars every year in order to bulk up to its size of three billion solar masses over just a few hundred million years. But where are all the stars
  • Near infrared views with the Hubble Space Telescope’s Wide Field Camera 3 are only providing hints of what might be taking place
  • galaxy is so enshrouded with dust that none of the starlight can be seen
  • only the bright, blaring quasar shines through
  • most early galaxies contain hardly any dust
  • the early universe was dust-free until the first generation of stars started making dust through nuclear fusion
  • quasar was first identified in the Sloan Digital Sky Survey (SDSS) and the follow-up submillimeter observations showed significant dust but not how and where
  • If you want to hide the stars with dust
  • make lots of short-lived massive stars earlier on that lose their mass at the end of their lifetime
  • used Hubble to very carefully subtract light from the quasar image and look for the glow of surrounding stars.
  • remarkable
  • Hubble didn’t find any of the underlying galaxy
  • Because we don’t see the stars, we can rule out that the galaxy that hosts this quasar is a normal galaxy
  • It’s among the dustiest galaxies in the universe
  • so widely distributed that not even a single clump of stars is peeking through
Mars Base

Game on! Researchers use online crowd-sourcing to diagnose malaria - 0 views

medicalxpress.com/...ne-crowd-sourcing-malaria.html

scibyte45 crowdsourcing medical

shared by Mars Base on 03 May 12 - No Cached
  • Online crowd-sourcing — in which a task is presented to the public, who respond, for free, with various solutions and suggestions — has been used to evaluate potential consumer products, develop software algorithms and solve vexing research-and-development challenges. But diagnosing infectious diseases
  • crowd-sourced online gaming system in which players distinguish malaria-infected red blood cells from healthy ones by viewing digital images obtained from microscopes.
  • recognize infectious diseases with the accuracy of trained pathologists
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  • UCLA Henry Samueli School of Engineering and Applied Science
  • Working on the assumption that large groups of public non-experts can be trained to recognize infectious diseases with the accuracy of trained pathologists
  • School of Medicine at UCLA
  • found that a small group of non-experts playing the game (mostly undergraduate student volunteers) was collectively able to diagnosis malaria-infected red blood cells with an accuracy that was within 1.25 percent of the diagnostic decisions made by a trained medical professional.
  • The game, which can be accessed on cell phones and personal computers, can be played by anyone around the world, including children
  • if you carefully combine the decisions of people — even non-experts — they become very competitive
  • if you just look at one person's response, it may be OK, but that one person will inevitably make some mistakes. But if you combine 10 to 20, maybe 50 non-expert gamers together, you improve your accuracy greatly in terms of analysis
  • could potentially help overcome limitations in the diagnosis of malaria
  • current gold standard for malaria diagnosis involves a trained pathologist using a conventional light microscope to view images of cells and count the number of malaria-causing parasites
  • process is very time-consuming, and given the large number of cases in resource-poor countries, the sheer volume presents a big challenge
  • significant portion of cases reported in sub-Sahara Africa are actually false positives, leading to unnecessary and costly treatments and hospitalizations
  • t the same platform could be applied to combine the decisions of minimally trained health care workers to significantly boost the accuracy of diagnosis, which is especially promising for telepathology, among other telemedicine field
  • By training hundreds, and perhaps thousands, of members of the public to identify malaria through UCLA's crowd-sourced game, a much greater number of diagnoses could be made more quickly — at no cost and with a high degree of collective accurac
  • research group created an automated algorithm for diagnosing the same images using computer vision, as well as a novel hybrid platform for combining human and machine resources toward efficient, accurate and remote diagnosis of malaria.
  • Before playing the game, each player is given a brief online tutorial and an explanation of what malaria-infected red blood cells typically look like using sample images
  • one of the major challenges will be the skepticism of traditional microscopists, pathologists and clinical laboratory personnel, not to mention malaria experts, who will initially view with suspicion a gaming approach in malaria diagnostics
Mars Base

Take a peek inside Curiosity's shell - 0 views

phys.org/...2-05-peek-curiosity-shell.html

scibyte46 Curiosity

shared by Mars Base on 09 May 12 - No Cached
  • Take a look around Curiosity’s cozy cabin!
  • didn’t get a window seat
  • the image above was taken by the rover’s Mars Hand Lens Imager (MAHLI) camera on April 20
  • ...4 more annotations...
  • color image was planned by the MSL team, used to confirm that MAHLI is operating as it should
  • two green dots are reflections of the camera’s LED lights
  • rusty-orange out-of-focus parts are cables
  • silver thing is a bracket holding said cables.
Mars Base

Spitzer sees the light of alien 'super earth' - 0 views

phys.org/...spitzer-alien-super-earth.html

scibyte45 exoplanet Spitzer

shared by Mars Base on 09 May 12 - No Cached
  • new information is consistent with a prior theory that 55 Cancri e is a water world: a rocky core surrounded by a layer of water in a "supercritical" state where it is both liquid and gas, and topped by a blanket of steam
Mars Base

Exeter biologist rediscovers 'forgotten' 19th century illustrations - 0 views

phys.org/...ediscovers-forgotten-19th.html

scibyte45f CollectionDigitized

shared by Mars Base on 09 May 12 - No Cached
  • unique collection of nineteenth century visual teaching aids belonging to the University of Exeter has been rediscovered after more than six decades
  • created by local naturalist Charles Thomas Hudson FRS to illustrate his lectures
  • They are framed paintings of microscopic animals and plants, all masked with thick brown paper
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  • When backlit in a darkened room the transparencies are transformed
  • illuminating the various organisms
  • have been kept in a dark room in the University’s Hatherly Laboratories since the 1960s.
  • storage conditions have proved ideal and the collection is still in excellent condition.
  • University of Exeter zoologist Dr. Robin Wootton, whose cataloguing project has brought the slides out of obscurity
  • painstakingly photographed each individual painting, using Photoshop Elements to optimise lighting and visibility.
  • the history of the transparencies
  • the University had acquired them from a Mrs F.R. Rowley on the death of her husband
  • in the late 1930s
  • it is possible that he may have known Hudson personally
Mars Base

Solar Tornadoes Dance Across Sun's Surface in NASA Video | Sun Tornado & Solar Flares |... - 0 views

www.space.com/-tornadoes-nasa-video-sdo.html

FebMedia

shared by Mars Base on 18 Feb 12 - No Cached
  • The tornado-like eruptions of super-hot plasma were spotted by NASA's Solar Dynamics Observatory, which is constantly recording high-definition videos of the sun.
  • shows swirling fountains of plasma creeping across the surface of the sun during a 30-hour period between Feb. 7 and 8.
  • unlike tornadoes on Earth, which are wind-driven phenomena, the sun's plasma tornadoes are shaped by the powerful magnetic field of our star.
  • ...10 more annotations...
  • active region rotating into view provides a bright backdrop to the gyrating streams of plasma
  • particles are being pulled this way and that by competing magnetic forces
  • tracking along strands of magnetic field lines
  • cooler plasma material appears as darker spots on a bright background
  • SDO spacecraft recorded the video in the extreme ultraviolet range of the light spectrum, giving the movie an eerie yellow hue.
  • released
  • SDO video
  • mark the second anniversary
  • on a five-year mission to record high-definition videos of the sun to help astronomers better understand how changes in the sun's solar weather cycle can affect life on Earth.
  • launched on Feb. 11, 2010
Mars Base

Orion Crew Capsule Targeted for 2014 Leap to High Orbit - 0 views

www.universetoday.com/...ed-for-2014-leap-to-high-orbit

scibyte39 orion

shared by Mars Base on 21 Mar 12 - No Cached
  • highest leap in human spaceflight in nearly 4 decades when an unmanned Orion crew capsule blasts off from Cape Canaveral, Fla., on a high stakes, high altitude test flight in early 2014.
  • narrated animation (see below) released by NASA depicts the planned 2014 launch of the Orion spacecraft on the Exploration Flight Test-1 (EFT-1) mission to the highest altitude orbit reached by a spaceship intended for humans since the Apollo Moon landing Era.
  • launch atop a Delta 4 Heavy booster rocket
  • ...5 more annotations...
  • capsule will then separate from the upper stage, re-enter Earth’s atmosphere at a speed exceeding 20,000 MPH
  • trio of huge parachutes and splashdown in the Pacific Ocean off the west coast of California.
  • altitude 15 times higher than the International Space Station (ISS) circling in low orbit some 250 miles above Earth and provide highly valuable in-flight engineering data that will be crucial for continued development of the spaceship.
  • Lockheed Martin is nearing completion of the initial assembly of the Orion EFT-1 capsule
  • first integrated launch of an uncrewed Orion is scheduled for 2017 on the first flight of NASA’s new heavy lift rocket
Mars Base

NASA - NASA Spacecraft Images Offer Sharper Views of Apollo Landing Sites - 0 views

www.nasa.gov/...apollo-sites.html

scibyte39 moon Apollo MarMedia

shared by Mars Base on 22 Mar 12 - No Cached
  • NASA's Lunar Reconnaissance Orbiter (LRO) captured the sharpest images ever taken from space of the Apollo 12, 14 and 17 landing sites
  • interactive shows two LRO images of the Apollo 17 landing site. Click and drag on the white slider bar to wipe from one to the other
  • This interactive shows two LRO images of the Apollo 12 landing site. Click and drag on the white slider bar to wipe from one to the other
  • ...5 more annotations...
  • can retrace the astronauts' steps with greater clarity to see where they took lunar samples
  • In the Apollo 17 image, the foot trails, including the last path made on the moon by humans
  • One of the details that shows up is a bright L-shape in the Apollo 12 image. It marks the locations of cables running from ALSEP's central station to two of its instruments. Although the cables are much too small for direct viewing, they show up because they reflect light very well.
  • higher resolution of these images is possible because of adjustments made to LRO's orbit, which is slightly oval-shaped or elliptical
  • paths left by astronauts Alan Shepard and Edgar Mitchell on both Apollo 14 moon walks are visible in this image. (At the end of the second moon walk, Shepard famously hit two golf balls.)
Mars Base

Mercury Surprises: Tiny Planet Has Odd Interior, Active Past | Messenger Spacecraft | S... - 0 views

www.space.com/ries-messenger-spacecraft.html

scibyte39 MarMedia mercury messenger

shared by Mars Base on 21 Mar 12 - No Cached
  • interior unlike that of any other rocky planet in our solar system and a surprisingly dynamic history,
  • remained geologically active for a surprisingly large chunk of its evolutionary history, researchers said
  • planet's huge iron core is even larger than they had thought
  • ...24 more annotations...
  • likely overlain with a solid shell of iron and sulfur
  • layered structure not known to exist on Earth, Venus or Mars
  • Messenger has taken nearly 100,000 images and made more than 4 million measurements of the planet's surface
  • probe is mapping Mercury's surface and gathering data on the planet's composition, magnetic environment and tenuous atmosphere, among other features
  • s original science campaign was designed to last one Earth year
  • NASA announced in November that it had granted the spacecraft a one-year mission extension
  • officially began its extended mission earlier this week.
  • In one study
  • They found that the range of elevations was smaller than that found on either Mars or the moon.
  • also observed that the floors of many Mercury craters have been tilted substantially
  • suggest that internal forces pushed the craters up after the impacts created them
  • not out of the question that Mercury is still active today
  • not very likely
  • have not observed an active eruption or extrusion
  • determined that Mercury has "mascons," large positive gravity anomalies associated with big impact basins
  • first discovered on the moon in 1968 and caused great problems in the Apollo program because they tugged low-orbiting spacecraft around and made navigation difficult
  • Subsequently mascons were discovered on Mars
  • find out that Mercury has
  • appear to be a common feature of terrestrial planetary bodies
  • gravity calculations also suggest that Mercury has an iron core that comprises roughly 85 percent of the planet's radius
  • Earth's iron core covers about half of its radius
  • new findings should help shed light on Mercury's past
  • formation and evolution of rocky planets in general
  • looks like a layer of solid iron sulfide overlies Mercury's core — a feature not known to exist on any other terrestrial planet
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