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Mars Base

Apollo Moon Rocks Challenge Lunar Water Theory: Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte83 moon

shared by Mars Base on 20 Feb 13 - No Cached
  • The discovery of "significant amounts" of water in moon rock samples collected by NASA's Apollo astronauts is challenging a longstanding theory about how the moon formed
  • Since the Apollo era, scientists have thought the moon came to be after a Mars-size object smashed into Earth early in the planet's history, generating a ring of debris that slowly coalesced over millions of years
  • That process, scientists have said, should have flung away the water-forming element hydrogen into space
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  • a new study suggests the accepted scenario is not possible given the amount of water found in moon rocks collected from the lunar surface in the early 1970s
  • By "water," the researchers don't mean liquid water, but hydroxyl, a chemical that includes the hydrogen and oxygen ingredients of water.
  • Those water-forming elements would have been on the moon all along
  • the impact scenario is the best formation scenario for the moon, but we need to reconcile the theory of hydrogen
  • Past studies have suggested water-forming elements came to the moon from outside sources long after the moon's crust cooled
  • The solar wind — a stream of particles emanating from the sun — as well as meteorites and comets were pegged as possible sources ofwater depositson the moon in recent studies
  • that explanation does not account for the amount of water found in the Apollo samples
  • Because they found hydroxyl deep inside each sampled rock, the scientists say they have eliminated the solar wind moon water explanation
  • those particles can penetrate the surface only slightly
  • An impact from an asteroid or comet could push the hydrogen in further, but it would not be as pristine as the samples the researchers observed, because it would have melted from the heat of the asteroid collision
  • Researchers probed samples from the late Apollo missions, including the famous "Genesis Rock" that was named for its advanced age of 4.5 billion years, about the same time the moon is thought to have formed
  • Using an infrared spectrometer, the researchers found water embedded in the Genesis Rock
  • implies that the various landing sites of Apollo 15, 16 and 17 each had water present
  • Hui's research flies in the face of past analyses of Apollo rocks that found they were very dry, except for a small bit of water attributed to the rock containers leaking when they were returned to Earth
  • Past instruments that analyzed these samples, however, were not very sensitive
  • older spectrometers had a sensitivity of around 50 parts per million (ppm), while his instruments were able to detect water at concentrations of about 6 ppm in anorthosites and 2.7 ppm in troctolites, which are both igneous rocks found in the moon's crust.
Mars Base

Confirmed: Dogs Sneak Food When People Aren't Looking - 0 views

news.nationalgeographic.com/...ogs-animals-science-mind-smart

scibyte83 dog

shared by Mars Base on 19 Feb 13 - No Cached
  • The research shows that domestic dogs, when told not to snatch a piece of food, are more likely to disobey the command in a dark room than in a lit room
  • The one thing we can say is that dogs really have specialized skills in reading human communication
  • This is special in dogs
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  • recruited 84 dogs, all of which were more than a year old, motivated by food, and comfortable with both strangers and dark rooms
  • The team then set up experiments in which a person commanded a dog not to take a piece of food on the floor
  • repeated the commands in a room with different lighting scenarios ranging from fully lit to fully dark
  • They found that the dogs were four times as likely to steal the food—and steal it more quickly—when the room was dark
  • the dog's behavior depended on whether the food was in the light or not, suggesting that the dog made its decision based on whether the human could see them approaching the food
  • were thinking what affected the dog was whether they saw the human, but seeing the human or not didn't affect the behavior
  • The study of dog cognition suddenly began about 15 years ago
  • Many of the new dog studies are variations on research done with chimpanzees, bonobos, and even young children
  • Selectively bred as companions for thousands of years, dogs are especially attuned to human emotions
  • are better at reading human cues than even our closest mammalian relatives
  • research reveals more and more insight into the minds
  • We still don't know just how smart they are
  • researchers are interested in whether the dog has a theory of mind
  • theory of mind is "an understanding that others have different perspective, knowledge, feelings than we do
  • Now, a new study suggests dogs might understand people even better than we thought
Mars Base

Tiny exoplanet smaller than Mercury: Smallest planet yet found outside solar system (Up... - 0 views

phys.org/...exoplanet-smaller-mercury.html

scibyte83 exoplanet

shared by Mars Base on 21 Feb 13 - No Cached
  • The bigger the star, the lower the frequency, or 'pitch' of its song
  • The team determined Kepler-37's mass is about 80 percent the mass of our sun
  • That's the lowest mass star astronomers have been able to measure using oscillation data for an ordinary star
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  • Those measurements also allowed the main research team to more accurately measure the three planets orbiting Kepler-37, including the tiny Kepler-37b
  • Kepler-37b is about 80% the size of Mercury and is the first exoplanet to be found that is smaller than any planet in our own Solar System
  • Kepler-37b is very likely a rocky planet with no atmosphere or water, similar to Mercury
  • "The detection of such a small planet shows for the first time that stellar systems host planets much smaller as well as much larger than anything we see in our own Solar System."
Mars Base

Naming Pluto's Moons: Will it Come Down to Trekkies Versus the IAU? - 0 views

www.universetoday.com/...own-to-trekkies-versus-the-iau

scibyte83 pluto

shared by Mars Base on 19 Feb 13 - No Cached
  • the SETI Institute has invited the public to vote on the names of Pluto’s 4th and 5th moons
Mars Base

Curiosity rover confirms first drilled Mars rock sample - 0 views

phys.org/...rover-drilled-mars-sample.html

scibyte83 Curiosity

shared by Mars Base on 21 Feb 13 - No Cached
  • NASA's Mars rover Curiosity has relayed new images that confirm it has successfully obtained the first sample ever collected from the interior of a rock on another planet
  • Transfer of the powdered-rock sample into an open scoop was visible for the first time in images received Wednesday
  • The drill on Curiosity's robotic arm took in the powder as it bored a 2.5-inch (6.4-centimeter) hole into a target on flat Martian bedrock on Feb. 8
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  • rover team plans to have Curiosity sieve the sample and deliver portions of it to analytical instruments inside the rover
  • The scoop now holding the precious sample is part of Curiosity's Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA)
  • During the next steps of processing, the powder will be enclosed inside CHIMRA and shaken once or twice over a sieve that screens out particles larger than 0.006 inch (150 microns) across
  • In response to information gained during testing at JPL, the processing and delivery plan has been adjusted to reduce use of mechanical vibration
  • The 150-micron screen in one of the two test versions of CHIMRA became partially detached after extensive use, although it remained usable
Mars Base

Smallest Exoplanet Yet Discovered by 'Listening' to a Sun-like Star - 0 views

www.universetoday.com/...y-listening-to-a-sun-like-star

scibyte83 exoplanet

shared by Mars Base on 21 Feb 13 - No Cached
  • Scientists have discovered a new planet orbiting a Sun-like star, and the exoplanet is the smallest yet found in data from the Kepler mission
  • Kepler-37b, is smaller than Mercury, but slightly larger than Earth’s Moon
  • discovery came from a collaboration between Kepler scientists and a consortium of international researchers who employ asteroseismology
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  • measuring oscillations in the star’s brightness caused by continuous star-quakes, and turning those tiny variations in the star’s light into sounds
  • The bigger the star, the lower the frequency, or ‘pitch’ of its song
  • The measurements made by the astroseismologists allowed the Kepler research team to more accurately measure the tiny Kepler-37b
  • revealing two other planets in the same planetary system: one slightly smaller than Earth and one twice as large
  • Kepler-37b is very likely a rocky planet with no atmosphere or water, similar to Mercury
  • “The detection of such a small planet shows for the first time that stellar systems host planets much smaller as well as much larger than anything we see in our own Solar System.”
  • host star, Kepler-37, is about 210 light-years from Earth
  • All three planets orbit the star at less than the distance Mercury is to the Sun
  • Kepler-37b orbits every 13 days at less than one-third Mercury’s distance from the Sun
  • estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin
  • hot enough to melt the zinc in a penny
  • Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively
  • The size of the star must be known in order to measure the planet’s size accurately
  • scientists examined sound waves generated by the boiling motion beneath the surface of the star
  • The technique for stellar seismology is analogous to how geologists use seismic waves generated by earthquakes to probe the interior structure of Earth
  • sound waves travel into the star and bring information back up to the surface
  • waves cause oscillations that Kepler observes as a rapid flickering of the star’s brightness
  • barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure
  • why most objects previously subjected to asteroseismic analysis are larger than the Sun
  • Kepler-37 has a radius just three-quarters of the Sun
  • the radius of the star is known to 3 percent accuracy, which translates to exceptional accuracy in the planet’s size.
  • this discovery took a long time to verify, as the signature of this very small exoplanet was hard to confirm
  • Kepler is sending astronomers photometry data that’s “probably the best we’ll see in our lifetimes
  • uncovered a planet smaller than any in our solar system orbiting one of the few stars that is both bright and quiet, where signal detection was possible
Mars Base

Has Dark Matter Finally Been Found? Big News Soon | Space.com - 0 views

www.space.com/ter-found-nasa-experiment.html

scibyte82 scibyte83 DarkMatter

shared by Mars Base on 19 Feb 13 - No Cached
  • the Alpha Magnetic Spectrometer, a particle collector mounted on the outside of the International Space Station
  • first paper of results
  • in about two weeks
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  • e said the results bear on the mystery of dark matter,
  • "It will not be a minor paper,"
  • important enough that the scientists rewrote the paper 30 times before they were satisfied with it
  • it represents a "small step" in figuring out what dark matter is, and perhaps not the final answer
  • Some physics theories suggest that dark matter is made of WIMPS (weakly interacting massive particles), a class of particles that are their own antimatter partner particles
  • When matter and antimatter partners meet, they annihilate each other, so if two WIMPs collided, they would be destroyed, releasing a pair of daughter particles — an electron and its antimatter counterpart, the positron, in the process
  • Alpha Magnetic Spectrometer has the potential to detect the positrons and electrons produced by dark matter annihilations in the Milky Way
  • was installed on the International Space Station in May 2011, and so far, it has detected 25 billion particle events, including about 8 billion electrons and positrons
  • This first science paper will report how many of each were found, and what their energies are
  • If the experiment detected an abundance of positrons peaking at a certain energy, that could indicate a detection of dark matter,
  • while electrons are abundant in the universe around us, there are fewer known processes that could give rise to positrons
  • The smoking gun signature is a rise and then a dramatic fall" in the number of positrons with respect to energy
  • he positrons produced by dark matter annihilation would have a very specific energy, depending on the mass of the WIMPs making up dark matter
  • Another telling sign will be the question of whether positrons appear to be coming from one direction in space, or from all around
  • f they're from dark matter, scientists expect them to be spread evenly through space, but if they're created by some normal astrophysical process, such as a star explosion, then they would originate in a single direction
  • There is a lot of stuff that can mimic dark matter,"
  • Regardless of whether AMS has found dark matter yet, the scientists said they expected the question of dark matter's origin to become clearer soon
Mars Base

Scientists sense breakthroughs in dark-matter mystery - 0 views

phys.org/...oughs-dark-matter-mystery.html

scibyte82 scibyte83 DarkMatter

shared by Mars Base on 19 Feb 13 - No Cached
  • Dark matter throws down the gauntlet to the so-called Standard Model of physics.
  • Elegant and useful for identifying the stable of particles and forces that regulate our daily life, the Standard Model only tells part of the cosmic story
  • it does not explain gravity, although we know how to measure gravity and exploit it for our needs
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  • the Standard Model has been found to account for only around four or five percent of the stuff in the Universe
  • dark matter, making up 23 percent, and dark energy, an enigmatic force that appears to drive the expansion of the Universe, which accounts for around 72 or 73 percent.
  • The dark matter theory was born 80 years ago when Swiss astrophysicist Fritz Zwicky discovered that there was not enough mass in observable stars or galaxies to allow the force of gravity to hold them together
  • why dark matter has six times the energy that is in ordinary matter
  • could be 10 trillions times bigger
  • first results will be published in two to three weeks
  • High-powered instruments track cosmic particles
  • To track these phantom particles, physicists rely on several methods and tools
  • One is the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station (ISS), which captures gamma rays coming from collisions of dark matter particles.
  • only suggesting that these highly anticipated results would give humans a better idea about the nature of dark matter
  • Another tool used by the scientists is the South Pole Neutrino Observatory, which tracks subatomic particles known as neutrinos, which, according to physicists, are created when dark matter passes through the Sun and interacts with protons
  • Another
  • is the Large Hadron Collider (LHC) near Geneva, the biggest particle smasher in the world
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