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Asteroid's troughs suggest stunted planet - 0 views

  • Scientists have been trying to determine the origin of these unusual troughs since their discovery just last year
  • new analysis supports the notion that the troughs are faults that formed when a fellow asteroid smacked into Vesta's south pole. The research reinforces the claim that Vesta has a layered interior, a quality normally reserved for larger bodies, such as planets and large moons.
  • ggest of those troughs, named Divalia Fossa, surpasses the size of the Grand Canyon by spanning 465 kilometers (289 miles) long, 22 km (13.6 mi) wide and 5 km (3 mi) deep
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  • The complexity of their formation can't be explained by simple collisions
  • New measurements
  • taken by NASA's Dawn spacecraft last year
  • indicate that a large collision could have created the asteroid's troughs
  • would only have been possible if the asteroid is differentiated – meaning that it has a core, mantle and crust
  • By saying it's differentiated, we're basically saying Vesta was a little planet trying to happen
  • previous research has found signs of igneous rock on Vesta, indicating that rock on Vesta's surface was once molten, a sign of differentiation
  • If the troughs are made possible by differentiation, then the cracks aren't just troughs, they're graben
  • graben is a dip in the surface that forms when two faults move apart from each other and the ground sinks into the widening gap
  • Vesta's troughs have many of the qualities of graben
  • observations indicate that Vesta is also unusually planet-like for an asteroid in that its mantle is ductile and can stretch under a lot of pressure
  • not yet fully convinced that Vesta's troughs are graben
  • There are other qualities of Vesta that could be clues to how the troughs formed
  • unlike the larger asteroid Ceres, Vesta is not classified as a dwarf planet because the large collision at its south pole knocked it out of its spherical shape
  • if Vesta has a mantle and core, that would mean it has qualities often reserved for planets, dwarf planets and moons—regardless of its shape
  • believes the south pole collision knocked Vesta into its current speedy rate of rotation about its axis of about once per 5.35 hours
  • may have caused the equator to bulge outward so far and so fast that the rotation caused the troughs, rather than the direct power of the impact
  • enigma why Vesta rotates so quickly
  • Dawn has already left to explore Ceres, so all the data it will retrieve on Vesta is in hand
  • scientists will continue to sort that data out and improve on computer simulations of Vesta's interior
Mars Base

Search for element 113 concluded at last - 0 views

  • do not occur in nature and must be produced through experiments involving nuclear reactors or particle accelerators
  • via processes of nuclear fusion or neutron absorption
  • Elements 93 to 103 were discovered by the Americans, elements 104 to 106 by the Russians and the Americans, elements 107 to 112 by the Germans, and the two most recently named elements, 114 and 116, by cooperative work of the Russians and Americans.
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  • On August 12, those experiments bore fruit: zinc ions travelling at 10% the speed of light collided with a thin bismuth layer to produce a very heavy ion followed by a chain of six consecutive alpha decays identified as products of an isotope of the 113th element
Mars Base

Buddhist statue, discovered by Nazi expedition, is made of meteorite, new study reveals - 0 views

  • a 1,000 year-old ancient Buddhist statue which was first recovered by a Nazi expedition in 1938 has been analysed by scientists and has been found to be carved from a meteorite
  • statue, known as the Iron Man, weighs 10kg and is believed to represent a stylistic hybrid between the Buddhist and pre-Buddhist Bon culture
  • discovered in 1938 by an expedition of German scientists
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  • expedition was supported by Nazi SS Chief Heinrich Himmler and the entire expeditionary team were believed to have been SS members.
  • unknown how the statue was discovered
  • believed that the large swastika carved into the centre of the figure may have encouraged the team to take it back to Germany
  • only became available for study following an auction in 2007.
  • first team to study the origins of the statue
  • The team was able to classify it as an ataxite
  • a rare class of iron meteorite with high contents of nickel.
  • statue was chiseled from a fragment of the Chinga meteorite which crashed into the border areas between Mongolia and Siberia about 15,000 years ago
  • first debris was officially discovered in 1913 by gold prospectors
  • believe that this individual meteorite fragment was collected many centuries before
Mars Base

Sumatra quake was part of crustal plate breakup: Study shows huge jolt measured 8.7, ri... - 0 views

  • Seismologists have known for years that the Indo-Australian plate of Earth's crust is slowly breaking apart
  • quake was caused by at least four undersea fault ruptures
  • within a 2-minute, 40-second period
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  • This is part of the messy business of breaking up a plate. … This is a geologic process
  • will take millions of years to form a new plate boundary
  • likely, it will take thousands of similar large quakes for that to happen."
  • All four faults
  • were strike-slip faults, meaning ground on one side of the fault moves horizontally past ground on the other side
  • great quake of last April 11 "is possibly the largest strike-slip earthquake ever seismically recorded
  • although a similar size quake in Tibet in 1950 was of an unknown type
  • 2012 quakes likely were triggered, at least in part, by changes in crustal stresses caused by the magnitude-9.1 Sumatra-Andaman earthquake of Dec. 26, 2004
  • the 8.7 and 8.2 quakes were generated by horizontal movements
  • not by vertical motion
  • explains why they didn't generate major tsunamis
  • 8.7 quake caused small tsunamis, the largest of which measured about 12 inches in height at Meulaboh, Indonesia
  • Indo-Australian plate is breaking into two or perhaps three pieces
  • happening because it is colliding with Asia in the northwest, which slows down the western part of the plate, while the eastern part of the plate continues moving more easily by diving or "subducting" under the island of Sumatra to the northeast
  • subduction zone off Sumatra caused the catastrophic 2004 magnitude-9.1 quake and tsunami
  • ruptured along a roughly 90-mile length
  • seafloor on one side of the fault slipped about 100 feet past the seafloor on the fault's other side
  • second fault, which slipped about 25 feet, began to rupture 40 seconds after
  • extended an estimated 60 miles to 120 miles north-northeast to south-southwest – perpendicular to the first fault and crossing it.
  • third fault was parallel to the first fault and about 90 to the miles southwest
  • started breaking 70 seconds after the quake began
  • along a length of about 90 miles
  • slipped about 70 feet
  • The fourth fault paralleled the first and third faults
  • began to rupture 145 seconds after the quake began
  • fault rupture was roughly 30 miles to 60 miles long.
  • fault slipped about 20 feet past ground on the other side
Mars Base

Google Lat Long: Dive into the Great Barrier Reef with the first underwater imagery in ... - 0 views

  • experience six of the ocean’s most incredible living coral reefs
  • sea turtle swimming among a school of fish
  • follow a manta ray
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  • experience the reef at sunset
  • see an ancient boulder coral, which may be several hundred years old
  • drift over the vast coral reef at Maui's Molokini crater
Mars Base

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

  • 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.
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  • 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

Cyclone Center - 0 views

  • The global intensity record contains uncertainties caused by differences in analysis procedures around the world and through time. Scientists are enlisting the public because patterns in storm imagery are best recognized by the human ey
Mars Base

For the first time, astronomers have measured the radius of a black hole - 0 views

  • an international team
  • , has for the first time measured the radius of a black hole at the center of a distant galaxy—the closest distance at which matter can approach before being irretrievably pulled into the black hole.
  • scientists linked together radio dishes in Hawaii, Arizona and California to create a telescope array called the "Event Horizon Telescope" (EHT) that can see details 2,000 times finer than what's visible to the Hubble Space Telescope.
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  • , the team observed the glow of matter near the edge of this black hole—a region known as the "event horizon."
  • , not everything can cross the event horizon to squeeze into a black hole
  • "cosmic traffic jam" in which gas and dust build up, creating a flat pancake of matter known as an accretion disk
  • disk of matter orbits the black hole at nearly the speed of light, feeding the black hole a steady diet of superheated material
  • Over time, this disk can cause the black hole to spin in the same direction as the orbiting material
  • Caught up in this spiraling flow are magnetic fields, which accelerate hot material along powerful beams above the accretion disk
  • resulting high-speed jet, launched by the black hole and the disk, shoots out across the galaxy, extending for hundreds of thousands of light-years
  • jets can influence many galactic processes, including how fast stars form.
  • . Because M87's jet is magnetically launched from this smallest orbit,
  • astronomers can estimate the black hole's spin through careful measurement of the jet's size as it leaves the black hole
  • Until now, no telescope has had the magnifying power required for this kind of observation
  • team used a technique called Very Long Baseline Interferometry, or VLBI, which links data from radio dishes located thousands of miles apart.
  • , taken together, create a "virtual telescope" with the resolving power of a single telescope as big as the space between the disparate dishes
  • enables scientists to view extremely precise details in faraway galaxies.
  • Using the technique
  • team measured the innermost orbit of the accretion disk to be only 5.5 times the size of the black hole event horizon
  • According to the laws of physics, this size suggests that the accretion disk is spinning in the same direction as the black hole
  • first direct observation to confirm theories of how black holes power jets from the centers of galaxies
  • The team plans to expand its telescope array, adding radio dishes in Chile, Europe, Mexico, Greenland and Antarctica, in order to obtain even more detailed pictures of black holes in the future.
  • www.eventhorizontelescope.org/
Mars Base

Mars Science Laboratory: Longest Drive Yet - 0 views

  • On Sol 50 (Sept. 26), Curiosity completed its longest drive yet, rolling about 160 feet (48.9 meters)
  • total distance driven has now reached one-quarter mile (416 meters).
  • Sol 50, in Mars local mean solar time at Gale Crater, ends at 4:29 p.m. Sept. 25, PDT (7:29 p.m. EDT).
Mars Base

Curiosity Finds Evidence of An Ancient Streambed on Mars - 0 views

  • said the rover has found “surprising” outcrops and gravel near the rover landing site that indicate water once flowed in this region, and likely flowed for a long time.
  • Too many things that point away from a single burst event
  • This is the first time we’re actually seeing water-transported gravel on Mars
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  • The discovery comes from examining two outcrops, called “Hottah” and “Link,” with the telephoto capability of Curiosity’s mast camera during the first 40 days
  • exposed by thruster exhaust as Curiosity touched down
  • We are getting better about integrating the orbital data,” said Grotzinger. “We see an alluvial fan and debris flow from orbit, and then see these water-transported pebbles from the ground
  • abundance of channels in the fan between the rim and conglomerate suggests flows continued or repeated over a long time, not just once or for a few years
  • Glenelg area marks the intersection of three kinds of terrain: bedrock for drilling, several small craters that may represent an older or harder surface, and also terrain similar to where Curiosity landed
  • can do comparisons
Mars Base

NASA - NASA Rover Finds Old Streambed on Martian Surface - 0 views

  • this evidence -- images of rocks containing ancient streambed gravels -- is the first of its kind
  • sizes and shapes of stones offer clues to the speed and distance of a long-ago stream's flow
  • can interpret the water was moving about 3 feet per second, with a depth somewhere between ankle and hip deep
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  • This is the first time we're actually seeing water-transported gravel on Mars
  • transition from speculation about the size of streambed material to direct observation of
  • finding site lies between the north rim of Gale Crater and the base of Mount Sharp, a mountain inside the crat
  • Earlier imaging of the region from Mars orbit allows for additional interpretation of the gravel-bearing conglomerate
  • rounded shape of some stones in the conglomerate indicates long-distance transport from above the rim
  • channel named Peace Vallis feeds into the alluvial fan.
  • abundance of channels in the fan between the rim and conglomerate suggests flows continued or repeated over a long time, not just once or for a few years.
  • discovery comes from examining two outcrops, called "Hottah" and "Link," with the telephoto capability of Curiosity's mast camera during the first 40 days after landing
  • observations followed up on earlier hints from another outcrop, which was exposed by thruster exhaust as Curiosity, the Mars Science Laboratory Project's rover, touched down
  • Hottah looks like someone jack-hammered up a slab of city sidewalk, but it's really a tilted block of an ancient streambed
  • gravels in conglomerates at both outcrops range in size from a grain of sand to a golf ball. Some are angular, but many are rounded
  • shapes tell you they were transported and the sizes tell you they couldn't be transported by wind
  • team may use Curiosity to learn the elemental composition of the material, which holds the conglomerate together, revealing more characteristics of the wet environment that formed these deposits
  • stones in the conglomerate provide a sampling from above the crater rim, so the team may also examine several of them to learn about broader regional geology.
  • slope of Mount Sharp in Gale Crater remains the rover's main destination
  • sulfate minerals detected there from orbit can be good preservers of carbon-based organic chemicals that are potential ingredients for life
Mars Base

Intraplate Quakes Signal Tectonic Breakup - Science News - 0 views

  • The first April 11 quake unzipped four perpendicular faults one after another in less than two minutes
  • They continued to resonate around the globe, triggering big aftershocks as far away as Mexico, a third study finds.
  • the number of quakes of magnitude 5.5 or greater, located more than 1,500 kilometers from the April 11 quakes, went up nearly fivefold for six days afterward
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  • Most giant quakes don’t trigger temblors so far away
  • The biggest
  • was a magnitude 7 in Baja California, about 22 hours afterward
  • the triggered quakes are well below magnitude 5
  • The difference, Pollitz says, lay in the strike-slip nature of the April 11 quakes
  • fault geometry allows the stress of a crustal movement to propagate much farther across the planet’s surface
Mars Base

Chocolate makes snails smarter - 0 views

  • some websites even maintain that dark chocolate can have beneficial effects
  • the science underpinning these claims, and you'll discover just how sparse it is
  • University of Calgary undergraduate
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  • became curious about how dietary factors might affect memory
  • Despite his misgivings
  • decided to concentrate on a group of compounds – the flavonoids – found in a wide range of 'superfoods' including chocolate and green tea, focusing on one particular flavonoid, epicatechin (epi).
  • figuring out how a single component of chocolate might improve human memory is almost impossible
  • too many external factors influence memory formation
  • the pond snail Lymnaea stagnalis, to find out whether the dark chocolate flavonoid could improve their memories
  • publish their discovery that epi improves the length and strength of snail memories in The Journal of Experimental Biology
  • molluscs can be trained to remember a simple activity: to keep their breathing tubes (pneumostomes) closed when immersed in deoxygenated water
  • t pond snails usually breathe through their skins, but when oxygen levels fall, they extend the breathing tube above the surface to supplement the oxygen supply
  • e snails can be trained to remember to keep the breathing tube closed in deoxygenated water by gently tapping it when they try to open it,
  • the strength of the memory depends on the training regime.
  • identified an epi concentration – 15 mg m3 pond water – that didn't affect the snails' behaviour
  • to be sure that we're not looking at wired animals
  • ested the molluscs' memories. Explaining that a half-hour training session in deoxygenated water allows the snails to form intermediate-term memories (lasting less than 3 h) but not long-term memories (lasting 24 h or more)
  • when Fruson plunged the molluscs into deoxygenated water to tested their memories a day later, they remembered to keep their breathing tubes closed
  • provided the snails with two training sessions, the animals were able to remember to keep their breathing tubes shut more than 3 days later
  • boosted the molluscs' memories and extended the duration, but how strong were the epi-memories
  • memories can be overwritten by another memory
  • process called extinction
  • the original memory is not forgotten and if the additional memory is stored weakly
  • can be lost and the original memory restored
  • then tried to replace it with a memory where the snails could open their breathing tubes
  • instead of learning the new memory, the epi-trained snails stubbornly kept their breathing tubes shut. The epi-memory was too strong to be extinguished.
  • also found that instead of requiring a sensory organ to consolidate the snails' memories – like their memories of predators triggered by smell – epi directly affects the neurons that store the memory
  • that the cognitive effects of half a bar of dark chocolate could even help your grades: good news for chocoholics the world over.
Mars Base

A Crescent Moon in the Martian Sky - 0 views

  • raw image taken on September 21 by Curiosity’s right Mastcam shows a daytime view of the Martian sky with a crescent-lit Phobos
  • image
  • is a crop of the original, contrast-enhanced and sharpened
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  • 13-km-wide Phobos has been spotted several times before by Mars rovers
  • most recently during a solar transit on September 13 (sol 37)
Mars Base

Guest Post: Comet Kerfuffle - 0 views

  • Comet. No, not Comet PANSTARRS, which is due to shine in the sky next March, perhaps rivalling the fondly-remembered Comet Hale Bopp from 1996
  • initial calculations of its orbit show it will pass ridiculously close to the Sun next November
  • Although Comet ISON looks promising, very promising in fact, it’s very early days. It needs to be observed a lot more before we know exactly what’s in store for us
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  • what it will actually look like in the sky is impossible to predict this far ahead
  • There’s a whole spectrum of possibilities here
  • SON will live up to the most breathless predictions and blaze in the sky
  • Its tail will span half the sky
  • becoming visible as soon as the Sun has set
  • At the other end of the spectrum, ISON will play us all for fools, and even before its close solar flyby it will break up without developing a searchbeam tail
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