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Mars Base

Astronomers discover first Thorne-Zytkow object, a bizarre type of hybrid star -- Scien... - 0 views

www.sciencedaily.com/...140604115117.htm

scibyte134 ThorneZytkowStar

shared by Mars Base on 05 Jun 14 - No Cached
  • While normal red supergiants derive their energy from nuclear fusion in their cores, TŻOs are powered by the unusual activity of the absorbed neutron stars in their cores
  • Thorne-Żytkow objects (TŻOs) are hybrids of red supergiant and neutron stars that superficially resemble normal red supergiants,
  • They differ, however, in their distinct chemical signatures
  • ...17 more annotations...
  • TŻOs are thought to be formed by the interaction of two massive stars―a red supergiant and a neutron star formed during a supernova explosion―in a close binary system
  • the most commonly held theory suggests that, during the evolutionary interaction of the two stars
  • the much more massive red supergiant essentially swallows the neutron star, which spirals into the core of the red supergiant
  • Studying these objects
  • represents a completely new model of how stellar interiors can work
  • In these interiors we also have a new way of producing heavy elements in our universe
  • The astronomers
  • examined the spectrum of light emitted from apparent red supergiants, which tells them what elements are present
  • When the spectrum of one
  • star -- HV 2112
  • were quite surprised by some of the unusual features
  • took a close look at the subtle lines in the spectrum they found that it contained excess rubidium, lithium and molybdenum
  • Past research has shown that normal stellar processes can create each of these elements
  • high abundances of all three of these at the temperatures typical of red supergiants is a unique signature of TŻOs
  • careful to point out that HV 2112 displays some chemical characteristics that don't quite match theoretical models
  • There are some minor inconsistencies between some of the details of what we found and what theory predicts
  • But the theoretical predictions are quite old, and there have been a lot of improvements in the theory since then
Mars Base

Researchers find spatial awareness shifts right as people fall asleep - 0 views

medicalxpress.com/...reness-shifts-people-fall.html

scibyte134

shared by Mars Base on 05 Jun 14 - No Cached
  • A team of researchers
  • has found that spatial awareness shifts to the right when people are falling asleep
  • another team of researchers reported noting that people experiencing reduced alertness due to sleepiness, tended to have alterations to their spatial awareness
Mars Base

Astronomers find a new type of planet: The 'mega-Earth' - 0 views

phys.org/...onomers-planet-mega-earth.html

scibyte134 exoplanet

shared by Mars Base on 05 Jun 14 - No Cached
  • Astronomers announced
  • that they have discovered a new type of planet - a rocky world weighing 17 times as much as Earth
  • Theorists believed such a world couldn't form because anything so hefty would grab hydrogen gas as it grew and become a Jupiter-like gas giant
  • ...28 more annotations...
  • This planet, though, is all solids and much bigger than previously discovered "super-Earths," making it a "mega-Earth."
  • Kepler-10c, circles a sunlike star once every 45 days
  • It is located about 560 light-years from Earth in the constellation Draco
  • The system also hosts a 3-Earth-mass "lava world," Kepler-10b, in a remarkably fast, 20-hour orbit
  • Kepler-10c was originally spotted by NASA's Kepler spacecraft.
  • By measuring the amount of dimming, astronomers can calculate the planet's physical size or diameter
  • Kepler can't tell whether a planet is rocky or gassy
  • Kepler-10c was known to have a diameter
  • , 2.3 times as large as Earth
  • This suggested it fell into a category of planets known as mini-Neptunes, which have thick, gaseous envelopes
  • The team used the HARPS-North instrument on the Telescopio Nazionale Galileo (TNG) in the Canary Islands to measure the mass of Kepler-10c
  • They found that it weighed 17 times as much as Earth - far more than expected.
  • This showed that Kepler-10c must have a dense composition of rocks and other solids.
  • Planet formation theories have a difficult time explaining how such a large, rocky world could develop
  • The early universe contained only hydrogen and helium
  • Heavier elements needed to make rocky planets, like silicon and iron, had to be created
  • When those stars exploded
  • scattered
  • through space, which then could
  • later generations of stars and planets
  • This process should have taken billions of years. However, Kepler-10c shows that the universe was able to form such huge rocks even during the time when heavy elements were scarce.
  • tells us that rocky planets could form much earlier than we thought. And if you can make rocks
  • This research implies that astronomers shouldn't rule out old stars when they search for Earth-like planets
  • if old stars can host rocky Earths too, then we have a better chance of locating potentially habitable worlds in our cosmic neighborhood
  • The Kepler-10 system is about 11 billion years old, which means it formed less than 3 billion years after the Big Bang
  • It's massive enough to have held onto
  • its atmosphere
  • if it ever had it
Mars Base

Contact With 36-Year Old Spacecraft Results in Dancing, Hugs. Now Comes Even Bigger Cha... - 0 views

www.universetoday.com/...ow-comes-even-bigger-challenge

scibyte134 ISEE-3

shared by Mars Base on 05 Jun 14 - No Cached
  • the spin rate of spacecraft is slightly below what it should be
  • the spacecraft is spinning at 19.16 rpm. “The mission specification is 19.75 +/- 0.2 rpm
  • are now receiving information from the spacecraft’s magnetometer
  • ...1 more annotation...
  • The next task will be looking at the propulsion system and making sure they can actually fire the engines for a trajectory correction maneuver (TCM), currently targeted for June 17.
Mars Base

Astronomers Find Evidence of a Strange Type of Star - 0 views

www.universetoday.com/...ence-of-a-strange-type-of-star

scibyte134 ThorneZytkowStar

shared by Mars Base on 05 Jun 14 - No Cached
  • a Thorne-Zytkow Object, or TZO
  • the outward appearance of
  • red supergiants
  • ...6 more annotations...
  • actually two stars in one: a binary pair where a super-dense neutron star has been absorbed into its less dense supergiant
  • First theorized in 1975
  • difficult to find in real life because of their similarity to red supergiants,
  • It’s only through detailed spectroscopy that the particular chemical signatures
  • can be identified.
  • Only by absorbing a much hotter star — such as a neutron star left over from the explosive death of a more massive partner — is the production of such elements presumed to be possible
Mars Base

Move Over, Gravity: Black Hole Magnetic Fields May Have Powerful Pull - 0 views

www.universetoday.com/...-fields-may-have-powerful-pull

scibyte134 BlackHole

shared by Mars Base on 05 Jun 14 - No Cached
  • It’s oft-repeated that black holes are powerful gravity wells, because they represent a dense concentration of matter in one location
  • magnetic fields
  • A new study suggests that
  • ...1 more annotation...
  • could be at least as strong as gravity in supermassive black holes, the singularities that lurk in the center of many galaxies
Mars Base

Lake on Saturn's Largest Moon May Have Waves - Scientific American - 0 views

www.scientificamerican.com/...-s-largest-moon-may-have-waves

scibyte134 titan

shared by Mars Base on 05 Jun 14 - No Cached
  • meras on NASA's spacecraft Cassini recently saw what appear to be waves on one of Titan's largest methane lakes
  • a signal scientists have long searched for but never found
  • If confirmed, the discovery would mark the first time waves have been seen outside Earth.
  • ...13 more annotations...
  • team found patterns in the sunlight reflecting off a northern lake called Punga Mare that they interpret as two-centimeter-high waves
  • There
  • may be a mudflat instead of a deep lake, and a shallow film of liquid on top may be the cause of the unique light signature
  • If life on Titan exists,
  • the best place to look
  • is in large bodies of liquid—the kind that form waves
  • Waves on Titan
  • would confirm that the lakes actually are deep reservoirs of methane and ethane,
  • True liquid bodies would also make a robotic spacecraft mission to explore Titan's habitability more feasible
  • By 2017 scientists should know for certain whether what they are seeing is indeed caused by waves
  • Cassini has been observing the moon during its northern winter, when weak winds are at work
  • As spring
  • over the next few years, bringing stronger winds to kick up seas, the probe should capture more definitive evidence of waves if they exist
Mars Base

Researchers find novel approach to reactivate latent HIV - 0 views

medicalxpress.com/...ach-reactivate-latent-hiv.html

scibyte134

shared by Mars Base on 06 Jun 14 - No Cached
  • A team of scientists
  • has identified a new way to make latent HIV reveal itself
  • could help overcome one of the biggest obstacles to finding a cure for HIV infection
  • ...18 more annotations...
  • They discovered that increasing the random activity, or noise, associated with HIV gene expression–without increasing the average level of gene expression–can reactivate latent HIV
  • When HIV infects an immune cell, it inserts its genetic material into the DNA of the infected cell
  • In most cases, the immune cell's
  • makes copies of the viral genetic material
  • eventually leads to the production
  • of all the components needed to make more viruses
  • In some cases, however, HIV
  • goes into a holding pattern and the virus enters a latent state within the infected immune cell
  • This means that a small percentage of HIV hides in infected cells, beyond the reach of even the most potent drugs
  • people with HIV infection have to take antiretroviral drugs (ARVs) for the rest of their lives
  • Roy Dar, PhD,
  • "If we can make the virus show itself, we can then use ARVs to eliminate it.
  • This so-called 'shock and kill' approach holds great promise, but to date it has unfortunately shown only limited success."
  • In this study, the team tested the counter-intuitive notion that compounds that increase noise in gene expression could work together with transcriptional activators to increase overall levels of HIV reactivation
  • They found that while the noise enhancers could not cause reactivation on their own, 75 percent of them could synergize with activators and increase viral reactivation relative to activator alone
  • some noise enhancers doubled reactivation levels when combined with activators
  • "The implications for using noise also extend far beyond HIV reactivation, since random cellular activity contributes to a wide range of processes, from antibiotic persistence to cancer metastasis
  • Dr. Weinberger
Mars Base

Hulk Smash! Collision That Formed Our Moon Shows Up In Lunar Rocks, Study Says - 0 views

www.universetoday.com/...s-up-in-lunar-rocks-study-says

scibyte134 LunarFormation

shared by Mars Base on 07 Jun 14 - No Cached
  • theory
  • Billions of years ago
  • , a Mars-sized body (sometimes called “Theia”) smashed into our young planet
  • ...14 more annotations...
  • Earth fortunately survived
  • and the fragments from the crash gradually coalesced into the Moon that we see today
  • scientists believe they have found traces of Theia in lunar rocks pulled from the Apollo missions
  • The isotopes or types of oxygen revealed in the new research appear to be different between the Earth and the Moon
  • implies that a body of different composition caused the changes
  • Before, the “resolution” of these microscopes couldn’t find any significant differences
  • the new data reveals the moon rocks have 12 parts per million more oxygen-17 than the Earth rocks
  • “The differences are small and difficult to detect, but they are there,” stated lead researcher Daniel Herwartz
  • means two things
  • first
  • can now be reasonably sure that the giant collision took place
  • Second
  • it gives us an idea of the geochemistry of Theia
  • The work was published in Science and will also be presented at the Goldschmidt geochemistry conference in California on June 11.
Mars Base

Could Pulses in Earth's Magnetic Field Forecast Earthquakes? | Science/AAAS | News - 0 views

news.sciencemag.org/...tic-field-forecast-earthquakes

scibyte134 earthquakes

shared by Mars Base on 07 Jun 14 - No Cached
  • In the days leading up to some recent moderate-sized earthquakes, instruments nearby have picked up brief low-frequency pulses in Earth’s magnetic field
  • A few scientists have proposed that such pulses, which seemed to become stronger and more frequent just before the earthquakes occurred, could serve as an early warning sign for impending seismic activity
  • Now, a team has come up with a model for how these magnetic pulses might be generated, though some critics say they may have a humanmade origin.
  • ...32 more annotations...
  • Brief fluctuations in Earth’s magnetic field have been detected before many earthquakes in the past 50 years
  • Friedemann Freund, a crystallographer at San Jose State University
  • in the weeks before a magnitude-5.4 quake struck about 15 kilometers northeast of San Jose in October 2007, an instrument near the epicenter sensed a number of unusual magnetic pulses
  • Those blips became more frequent as the day of the earthquake approached, Freund says
  • recently, prior to several medium- to moderate-sized quakes in Peru, two sensitive magnetometers recorded the same sort of pulses
  • how such pulses could be generated
  • suggest that these blips stem from microscopic changes in crystals in rocks under seismic stress deep within Earth
  • In many types of rocks, particularly volcanic rocks that have substantial amounts of water locked inside them, crystals are chock-full of oxygen-oxygen bonds called peroxy bonds
  • (These bonds formed long ago, after chemical changes split some of the water molecules, freeing the hydrogen atoms to bond together and then diffuse out of the rocks as gas.)
  • When those rocks are squeezed, say, by the sides of a fault zone scraping past one another, some of the peroxy bonds break
  • Those broken bonds release negatively charged electrons, which remain trapped in place, and create positively charged “holes” in the crystal
  • his team propose that the same process might be happening within Earth’s crust
  • As stress on large volumes of rock builds in advance of an impending quake, many, many of these electrical holes are created inside them
  • the mass migration of such holes that creates the large electrical currents responsible for generating the low-frequency magnetic pulses that make their way to detectors on Earth’s surface
  • they say
  • some critics of his model have proposed
  • lightning
  • as an alternative explanation
  • he notes, with data from the two sensors in Peru he and his colleagues were able to pinpoint the strongest of those pulses as originating within a few kilometers of the epicenters of subsequent quakes
  • For now, Freund admits, the team’s model is preliminary: The paper has been submitted to a journal and is now being reviewed by other scientists.
  • two instruments aren’t sufficient to pinpoint the location of an event; to truly “triangulate” an event you need at least three sensors
  • “I’m concerned that the pulses are not originating deep within the Earth.”
  • “This paper only makes sense if the observations [of magnetic pulses] are good,”
  • John Ebel, a seismologist at Boston College, who wasn’t involved in the research
  • the blips may have some inexplicable humanmade origin
  • Decades ago
  • his Boston-based magnetometers started picking up a series of odd pulses every morning.
  • Eventually
  • identified
  • It was the engineers cranking up Boston’s trolley cars at a rail yard a few kilometers away from the instruments
  • Even if the magnetic pulses originate within Earth along seismic zones under stress, Freund says, the blips don’t always foretell a quake
  • It’s more likely to be the pattern of pulses—and, in particular, changes in their size and frequency—that Freund and his colleagues say might offer scientists a crystal ball for impending temblors
Mars Base

This Week's Sky at a Glance, June 6 - 14 | Sky & Telescope - 0 views

www.skyandtelescope.com/...weeks-sky-glance-june-6-14

scibyte134 LookingUp

shared by Mars Base on 08 Jun 14 - No Cached
  • Thursday, June 12
  • Full Moon
  • Friday, June 13
  • ...10 more annotations...
  • Vega is the brightest star shining in the east after dusk. It's currently the top star of the big Summer Triangle. The brightest star to Vega's lower left is Deneb. Look farther to Vega's lower right for Altair. The Summer Triangle will climb higher in early evening all through the summer, to pose highest overhead at dusk when fall begins
  • Venus
  • low in the east during dawn.
  • Mars (
  • high in the south-southwest in late twilight
  • Mars sets in the west around 2 a.m. daylight saving time
  • Jupiter
  • low in the west-northwest in twilight and sets around nightfall
  • southeast to south during evening
  • Saturn (
Mars Base

NASA's LDSD 'Flying Saucer' Test--Update - Mars Science Laboratory - 0 views

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

scibyte134 Curiosity

shared by Mars Base on 08 Jun 14 - No Cached
  • NASA's flying saucer-shaped test vehicle is ready
  • for its first engineering shakeout flight.
  • The Low Density Supersonic Decelerator (LDSD) will gather data about landing heavy payloads on Mars and other planetary surfaces
  • ...14 more annotations...
  • As NASA plans increasingly ambitious robotic missions to Mars, laying the groundwork for even more complex human science expeditions to come, accommodating extended stays for explorers on the Martian surface will require larger and heavier spacecraft
  • use a helium balloon -- that, when fully inflated, would fit snugly into Pasadena's Rose Bowl
  • to lift our vehicle to 120,000 feet
  • A fraction of a second after dropping from the balloon, and a few feet below it, four small rocket
  • stabilize the saucer.
  • A half second later, a
  • solid-fueled rocket engine will
  • sending the test vehicle to the edge of the stratosphere
  • "Our goal is to get to an altitude and velocity which simulates the kind of environment one of our vehicles would encounter when it would fly in the Martian atmosphere," said Ian Clark, principal investigator of the LDSD project at JPL
  • to fly the two supersonic decelerator technologies that will be thoroughly tested during two LDSD flight tests next year.
  • The SIAD-R, essentially an inflatable doughnut that increases the vehicle's size and, as a result, its drag
  • . It will quickly slow the vehicle
  • where the
  • the largest supersonic parachute ever flown, first hits the supersonic flow
Mars Base

Curiosity Captures Mercury from Mars - 0 views

www.universetoday.com/...ity-captures-mercury-from-mars

scibyte134 Curiosity

shared by Mars Base on 11 Jun 14 - No Cached
  • NASA’s Curiosity rover
  • does get a chance to skygaze on occasion. And while looking at the Sun on June 3, 2014
  • the rover’s Mastcam spotted
  • ...8 more annotations...
  • Mercury
  • across the Sun’s face
  • Silhouetted against the bright disk of the Sun, Mercury barely appears as a hazy blur in the filtered Mastcam images
  • it was moving relatively quickly during the transit, passing the darker smudges of two Earth-sized sunspots over the course of several hours.
  • It’s the first time Mercury has ever been imaged from Mars
  • the first time we’ve observed a planet transiting our Sun from another world besides our own
  • this was
  • a carefully calculated observation using the Mastcam’s right 100mm telephoto lens and neutral density filter, which is used to routinely image the Sun in order to measure the dustiness of the Martian atmosphere
Mars Base

Reversal of type 1 diabetes in mice may eventually help humans - 0 views

medicalxpress.com/...es-mice-eventually-humans.html

scibyte135 Diabetes

shared by Mars Base on 15 Jun 14 - No Cached
  • Investigators at the University of Cincinnati (UC) have found a therapy that reverses new onset Type 1 diabetes in mouse models and may advance efforts in combating the disease among humans.
  • Type 1 diabetes is usually diagnosed in children and young adults and affects about 5 percent of all people with diabetes
  • . In Type 1 diabetes, the body does not produce sufficient insulin, which is central to glucose metabolism: without insulin, blood glucose rises
  • ...15 more annotations...
  • There is no cure for Type 1 diabetes though it can be controlled with insulin therapy
  • by using an antibody to stimulate a specific molecule in the innate immune system we can reverse—with a high rate of success—new onset diabetes in mice that have already developed the symptoms of diabetes
  • The cause of this reversal is a preservation of the endocrine pancreatic beta cells that produce insulin
  • These cells are preserved from the autoimmune attack which is the hallmark of Type 1 diabetes
  • The key to reversing Type 1 diabetes in mice,
  • is catching the disease at its onset, which is typically within a very short time window
  • The time frame would be longer in humans, but it is still a relatively short time from new onset to end-stage Type 1 diabetes
  • Ridgway says this approach differs from most in combating Type 1 diabetes because his team's therapies in mice do not directly interact with T-cells
  • treatment of autoimmunity has often been directed at suppressing an over-zealous adaptive immune response by eliminating auto-reactive T-cells
  • In Type 1 diabetes, autoimmunity causes the body's T-cells to attack its insulin-producing beta cells.
  • targeting a different part of the immune system
  • There are two arms of the immune system.
  • respond to many different antigens
  • The innate system tends to have a stereotypical response. We are targeting a receptor that is found mostly on the innate immune cells, such as dendritic cells.
  • Additional study will be required, but the therapy may hold promise because one agonistic anti-TLR4 agent is already FDA approved and others are under development
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