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Mars Base

Ancient Egyptians transported pyramid stones over wet sand - 0 views

phys.org/...tians-pyramid-stones-sand.html

scibyte129

shared by Mars Base on 02 May 14 - No Cached
  • Physicists
  • have discovered that the ancient Egyptians used a clever trick to make it easier to transport heavy pyramid stones by sledge
  • The Egyptians moistened the sand over which the sledge moved.
  • ...16 more annotations...
  • By using the right quantity of water they could halve the number of workers needed
  • For the construction of the pyramids, the ancient Egyptians had to transport heavy blocks of stone and large statues across the desert
  • The Egyptians therefore placed the heavy objects on a sledge that workers pulled over the sand
  • Research
  • revealed that the Egyptians probably made the desert sand in front of the sledge wet
  • Experiments have demonstrated that the correct amount of dampness in the sand halves the pulling force required
  • physicists placed a laboratory version of the Egyptian sledge in a tray of sand
  • determined both the required pulling force and the stiffness of the sand as a function of the quantity of water in the sand.
  • To determine the stiffness they used a rheometer, which shows how much force is needed to deform a certain volume of sand
  • Experiments revealed that the required pulling force decreased proportional to the stiffness of the sand
  • Capillary bridges arise when water is added to the sand. These are small water droplets that bind the sand grains together
  • In the presence of the correct quantity of water, wet desert sand is about twice as stiff as dry sand
  • A sledge glides far more easily over firm desert sand simply because the sand does not pile up in front of the sledge as it does in the case of dry sand.
  • A wall painting in the tomb of Djehutihotep clearly shows a person standing on the front of the pulled sledge and pouring water over the sand just in front of it.
  • the results are also interesting for modern-day applications. We still do not fully understand the behaviour of granular material like sand
  • The research results could therefore be useful for examining how to optimise the transport and processing of granular material, which at present accounts for about ten percent of the worldwide energy consumption
Mars Base

Rare Water-Rich Mars Meteorite Discovered : Discovery News - 0 views

news.discovery.com/...rs-meteorite-found-120103.html

scibyte76 mars

shared by Mars Base on 04 Jan 13 - No Cached
  • A rare Martian meteorite recently found in Morocco contains minerals with 10 times more water than previously discovered Mars meteorites
  • raises new questions about when and how long the planet most like Earth in the solar system had conditions suitable for life
  • believed to be similar to those studied by NASA's Spirit and Opportunity rovers
  • ...15 more annotations...
  • known as Northwest Africa (NWA) 7034, is the second-oldest of 110 named stones originating from Mars that have been retrieved on Earth
  • Purchased from a Moroccan meteorite dealer in 2011, the black, baseball-sized stone, which weighs less than 1 pound, is 2.1 billon years old, meaning it formed during what is known as the early Amazonian era in Mars' geologic history.
  • The only older Mars meteorite found so far is the 4-billion-year-old Allan Hills 84001 Antarctica stone that was the source of speculation about microfossils in 1996
  • Early Mars was believed to be warm and wet, but the planet lost most of its atmosphere and its surface water to become a cold, dry desert that appears today
  • The time from when our meteorite is from is maybe a transitional period in the climate, when Mars was losing its atmosphere, losing its water on the surface
  • relatively rich in water -- about 6,000 parts per million -- compared with typical Martian meteorites that contain about 200- to 300 parts per million
  • similar to basaltic rocks on Earth that form in volcanic eruptions
  • NWA 7034, nicknamed "Black Beauty," also contains tiny bits of carbon, formed from geologic, not biological activity
  • Scientists don't know why more meteorites like Black Beauty haven't been found on Earth. The period of time from which they originated may be relatively short, or most may not survive the trip through Earth's atmosphere
  • This one does look completely different," he added. "It's jet black. The others are slightly greenish cast
  • After an initial battery of tests revealed the rock's unique nature, meteorite hunters returned to the area where it was found to search for other similar stones
  • took several months to get an idea of what it was
  • eventually realized there was no other conclusion but that it was Martian and that it was different from all the other ones
  • If it were similar, we would have known within one day," he added
  • Four more pieces, all smaller than the original, have now been found
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

Polymer Power Drives Tiny Reactions - Science News - 0 views

www.sciencenews.org/...er_power_drives_tiny_reactions

scibyte38

shared by Mars Base on 14 Mar 12 - No Cached
  • Applying force to polymers in water generates enough energy to drive chemical reactions
  • won’t replace large-scale energy operations
  • offers a way to harness the wisps of unused energy generated by everyday endeavors, like walking or compacting plastic bags at a recycling center
  • ...13 more annotations...
  • capturing such energy could lead to cheap, clean ways to sanitize a small container of water, for example, or to run a simple lab bench reaction
  • Scientists knew that bonds can break when mechanical force is applied to a polymer
  • breakage can generate free radicals, atoms with unpaired electrons that are eager to engage in further reactions
  • new work shows that when a polymer is squeezed in water, the free radicals migrate and react with the water, generating enough hydrogen peroxide to spur other reactions.
  • When the scientists added gold and silver metal salts to a PDMS tube filled with water, squeezing the tube powered reactions that generated gold and silver nanoparticles
  • also injected the sole of a Nike LeBron sneaker with water and a compound that fluoresces when it is cleaved
  • Half an hour of walking applied force to the polymers in the sneaker’s sole, and the resulting free radicals made enough hydrogen peroxide to cleave the fluorescing compound and make the sole glow. 
  • capturing and converting the mechanical energy of polymer squeezing into energy for driving reactions can be as efficient as 30 percent
  • comparable to some power plants that use coal.
  • PDMS is used in some medical devices such as catheters, and in some breast implants, raising the issue that normal wear in the body might generate free radicals that could cause inflammation and other problems
  • adding an antioxidant such as vitamin E, which latches onto free radicals, to the implant ingredients might be a quick and easy way to
  • Some of the body’s immune cells, though, generate well more hydrogen peroxide than that generated by the polymers
  • the fact that enough free radicals are generated to drive reactions — which might even contribute to the breakdown of medical devices — is interesting, Tang says. “I don’t know how unique it is or material-specific, but it could have potential importance.”
Mars Base

Water Ice in Moon's Shackleton Crater Identified | Space.com - 0 views

www.space.com/ter-ice-shackleton-crater.html

LunarWater

shared by Mars Base on 21 Jun 12 - No Cached
  • sits almost directly on the moon's south
  • more than 12 miles wide (19 kilometers) and 2 miles deep (3 km) — about as deep as Earth's oceans.
  • in nearly perpetual darkness
  • ...11 more annotations...
  • Japanese spacecraft Kaguya saw no discernible signs of
  • NASA's LCROSS probe analyzed Cabeus Crater near the moon's south pole and found it measured as much as 5 percent water by mass
  • crater's floor is more reflective than that of other nearby craters, suggesting it had ice.
  • The amount of ice in Shackleton Crater "can also be much less, conceivably as little as zero
  • Bizarrely, while the crater's floor was relatively bright, Zuber and her colleagues observed that its walls were even more reflective.
  • researchers think the reflectance of the crater's walls is due not to ice, but to quakes
  • may have caused Shackleton's walls to slough off older, darker soil, revealing newer, brighter soil underneath
  • reflectance could be indicative of something else in addition to or other than water ice
  • might be reflective because it could have had relatively little exposure to solar and cosmic radiation that would have darkened it.
  • measurements only look at a micron-thick portion of Shackleton Crater's uppermost layer
  • bigger question is how much water might be buried at depth
Mars Base

Curiosity Discovers Patch of Pebbles Formed by Flowing Martian Water on Mount Sharp Trek - 0 views

www.universetoday.com/...tian-water-on-mount-sharp-trek

scibyte104

shared by Mars Base on 27 Sep 13 - No Cached
  • Curiosity
  • has discovered a new patch of pebbles formed and rounded eons ago by flowing liquid water
  • the new finding at a sandstone outcrop called ‘Darwin’ during a brief science stopover spot called ‘Waypoint 1’.
  • ...7 more annotations...
  • The discovery at Darwin is significant because it significantly broadens the area here that was altered by flowing liquid water
  • The robot pulled into ‘Waypoint 1’ on Sept. 12 (Sol 392).
  • Did the water flow that deposited the pebbly sandstone at Waypoint 1 occur at about the same time as the water flow at Yellowknife Bay?
  • If the same fluid flow produced the veins here and the veins at Yellowknife Bay, you would expect the veins to have the same composition.’
  • the veins are different, so we know the history is complicated. We use these observations to piece together the long-term history
  • Darwin comes from a list of 100 names the team put together to designate rocks in the Mawson Quadrangle
  • on Sept. 22, the rover departed Darwin and Waypoint 1 on a westward heading to resume the many months long journey to Mount Sharp
Mars Base

Bering Strait may be global temperature stabilizer - 0 views

phys.org/...al-temperature-stabilizer.html

scibyte42 BeringStrait

shared by Mars Base on 11 Apr 12 - No Cached
  • normally the AMOC causes cycling of warm water from the south to flow north, and cold water from the north to flow south
  • engine for this system is cold salt laden water in the north sinking beneath incoming warm water
  • If the cold water in the north is fresh, as it would be if it were coming from the melted glaciers, then it wouldn’t sink and the whole AMOC system would stop
  • ...2 more annotations...
  • if it stopped, air temperatures could change quickly.
  • computer simulation actually showed the same temperature fluctuations over Greenland as researchers have found, via core ice samples, occurred the last time the Strait closed during the last Ice Age.
Mars Base

APOD: 2012 May 24 - All the Water on Europa - 0 views

apod.nasa.gov/ap120524.html

scibyte48 earth Europa water

shared by Mars Base on 24 May 12 - No Cached
  • Based on the Galileo probe data acquired during its exploration of the Jovian system from 1995 to 2003
  • Europa possesses a deep, global ocean of liquid water beneath a layer of surface ice
  • The subsurface ocean plus ice layer could range from 80 to 170 kilometers in average dept
  • ...3 more annotations...
  • estimate of 100 kilometers depth
  • all the water on Europa were gathered into a ball it would have a radius of 877 kilometers
  • a volume 2-3 times the volume of water in Earth's oceans
Mars Base

Chocolate makes snails smarter - 0 views

phys.org/...-chocolate-snails-smarter.html

scibyte65 chocolate

shared by Mars Base on 27 Sep 12 - No Cached
  • 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
  • ...25 more annotations...
  • 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

Desert Farming Experiment Yields First Results | Science/AAAS | News - 0 views

news.sciencemag.org/...xperiment-yields-first-results

scibyte110 Farming

shared by Mars Base on 17 Nov 13 - No Cached
  • A project to “green” desert areas with an innovative mix of technologies—producing food, biofuel, clean water, energy, and salt
  • A pilot plant built by the Sahara Forest Project (SFP) produced 75 kilograms of vegetables per square meter in three crops annually, comparable to commercial farms in Europe, while consuming only sunlight and seawate
  • The heart of the SFP concept is a specially designed greenhouse. At one end, salt water is trickled over a gridlike curtain so that the prevailing wind blows the resulting cool, moist air over the plants inside
  • ...12 more annotations...
  • This cooling effect allowed the
  • facility to grow three crops per year, even in the scorching summer
  • At the other end of the greenhouse is a network of pipes with cold seawater running through them
  • Some of the moisture in the air condenses on the pipes and is collected, providing a source of fresh water
  • One of the surprising side effects of such a seawater greenhouse, seen during early experiments, is that cool moist air leaking out of it encourages other plants to grow spontaneously outside
  • Qatar plant took advantage of that effect to grow crops around the greenhouse, including barley and salad rocket (arugula), as well as useful desert plants
  • The pilot plant accentuated this exterior cooling with more “evaporative hedges” that reduced air temperatures by up to 10°C.
  • The third key element of the SFP facility is a concentrated solar power plant
  • This uses mirrors in the shape of a parabolic trough to heat a fluid flowing through a pipe at its focus. The heated fluid then boils water, and the steam drives a turbine to generate power
  • the plant has electricity to run its control systems and pumps and can use any excess to desalinate water for irrigating the plants
  • The fact that this small greenhouse produced such good yields,
  • suggests that a commercial plant—with possibly four crops a year—could do even better
Mars Base

Distant planets' atmospheres revealed | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/...t_planets_atmospheres_revealed

scibyte86 exoplanet

shared by Mars Base on 15 Mar 13 - No Cached
  • Astronomers have gotten the most detailed look yet at the atmosphere of a planet outside the solar system
  • The study is among the first to directly analyze the chemical makeup of an exoplanet
  • In the past, astronomers inferred the existence of exoplanets and their gases by looking for subtle changes in the light streaming from the planet’s star
  • ...42 more annotations...
  • Now, with improved instruments, a team
  • has detected light coming directly from a planet light-years away
  • The data have high enough resolution to reveal not only the presence but the abundance of carbon monoxide and water in the planet’s atmosphere
  • Such information could shed light on how the planet formed
  • studies could also reveal the presence of life on a distant planet, but the planet’s size and orbit have already ruled it out as a habitable world
  • In 2008
  • the first image of a multiplanet system outside the solar system, showing three gas giants orbiting the star HR 8799
  • HR 8799 is about 130 light-years from Earth, in the constellation Pegasus
  • The planets are scorching hot, making them bright enough for astronomers to detect directly
  • In 2010, the researchers imaged a fourth planet around HR 8799
  • In the new study
  • focused on one of these planets, HR 8799c.
  • Five to 10 times as massive as Jupiter, HR 8799c sits about eight times farther away from its star than Jupiter does from the sun
  • Because of that great distance, the astronomers could block the star’s light and record infrared light
  • Because different gases absorb and emit light in distinct ways, the team could identify carbon monoxide and water but found no methane, which scientists had thought might be present.
  • In another new study
  • researchers simultaneously collected infrared light from the atmospheres of all four planets
  • A team led by
  • an astrophysicist at the American Museum of Natural History in New York City, found hints of ammonia, methane, carbon dioxide and acetylene in the planets’ atmospheres
  • The chemistry of each planet varies
  • different from anything in our own solar system
  • Although the teams looked at different wavelengths of light, which pick up different types of molecules, the two studies appear consistent
  • by peering at just one planet, Konopacky’s team obtained more detailed data that allowed the researchers to get a sense of how much carbon and oxygen is in HR 8799c’s atmosphere
  • Knowing the ratio of carbon to oxygen in the atmosphere may reveal how the planet formed
  • Astronomers have two competing theories of how planets arise from the disk of gas and dust encircling a young star
  • In the gravitational instability model, some of the gas and dust suddenly clumps and collapses, simultaneously creating a planet’s core and atmosphere
  • In this scenario, the chemical composition of a planet should match that of its star
  • In the other model, known as core accretion, planet building is a two-step process
  • First, material from the disk accumulates into a core.
  • Later, the core captures gases swirling in the disk to form an atmosphere.
  • In this case, the carbon-to-oxygen ratio of the planet may differ from the star because the accretion of cores may deplete the disk of certain elements
  • Compared with its star, HR 8799c appears to have slightly more carbon relative to oxygen, suggesting the planet originated via core accretion
  • surmise that when the disk around HR 8799 formed, water froze into particles of ice.
  • The bits of ice collided to form the planet’s core, leaving behind little water vapor, and therefore less oxygen, when the planet accumulated its atmosphere later on
  • Other researchers are not convinced by this conclusion
  • “We don’t really understand planetary formation enough to make a strong case either way,”
  • the data from both new studies may help astronomers refine their simulations of planetary formation
  • astronomers have directly imaged planets around three distant stars
  • researchers are poised to capture light from many more planets
  • Project 1640,
  • is looking for Jupiter-sized planets around some 200 stars
  • “Ultimately, with better instruments, people will be able to use these methods on Earthlike planets.”
Mars Base

Opportunity Discovers Clays Favorable to Martian Biology and Sets Sail for Motherlode o... - 0 views

www.universetoday.com/...il-for-motherlode-of-new-clues

scibyte95 opportunity

shared by Mars Base on 26 May 13 - No Cached
  • Opportunity,
  • has just discovered the strongest evidence to date for an environment favorable to ancient Martian biology
  • Opportunity’s analysis of a new rock target named “Esperance” confirmed that it is composed of a “clay that had been intensely altered by relatively neutral pH water – representing the most favorable conditions for biology that Opportunity has yet seen in the rock histories it has encountered
  • ...9 more annotations...
  • Water that moved through fractures during this rock’s history would have provided more favorable conditions for biology than any other wet environment recorded in rocks Opportunity has seen
  • Opportunity accomplished the ground breaking new discovery by exposing the interior of Esperance with her still functioning Rock Abrasion Tool (RAT) and examining a pristine patch using the microscopic camera and X-Ray spectrometer on the end of her 3 foot long robotic arm.
  • “Esperance was so important, we committed several weeks to getting this one measurement of it
  • Esperance stems from a time when the Red Planet was far warmer and wetter billions of years ago.
  • made the discovery at the conclusion of a 20 month long science expedition circling around a low ridge called “Cape York”
  • What’s so special about Esperance is that there was enough water not only for reactions that produced clay minerals, but also enough to flush out ions set loose by those reactions
  • Opportunity can clearly see the alteration
  • Esperance is unlike any rock previously investigated by Opportunity; containing far more aluminum and silica which is indicative of clay minerals and lower levels of calcium and iron.
  • Most, but not all of the rocks inspected to date by Opportunity were formed in an environment of highly acidic water
Mars Base

Soybeans soaked in warm water naturally release key cancer-fighting substance - 0 views

phys.org/...cancer-fighting-substance.html

scibyte46 medical Cancer MedicalTreatment

shared by Mars Base on 10 May 12 - No Cached
  • Soybeans soaked in warm water naturally release key cancer-fighting substance
  • Protease Inhibitor (BBI), has shown promise for preventing certain forms of cancer in clinical trials.
  • BBI derived from the large amounts of soybeans in traditional Japanese diets might underpin low cancer mortality rates in Japan
  • ...4 more annotations...
  • the current method of extracting BBI from soybeans is time-consuming and involves harsh chemicals
  • soybean seeds incubated in water at 122 degrees Fahrenheit naturally release large amounts of BBI that can easily be harvested from the water
  • protein appeared to be active
  • tests showing that it stopped breast cancer cells from dividing in a laboratory dish
Mars Base

Oil spill cleanup: Smart filter can strain oil out of water - 0 views

phys.org/...eanup-smart-filter-strain.html

scibyte61

shared by Mars Base on 29 Aug 12 - No Cached
  • researchers created a filter coating that repels oil but attracts water
  • Most natural substances soak up oil, and the few that repel it also repel water because water has a higher surface tension
  • , the researchers dipped postage-stamp-size pieces of stainless steel window screen and polyester fabric into their solution
  • ...1 more annotation...
  • cured the coated snippets under ultraviolet light
Mars Base

Sea turtles 'lost years' mystery starts to unravel - 0 views

phys.org/...urtles-lost-years-mystery.html

scibyte123

shared by Mars Base on 05 Mar 14 - No Cached
  • Small satellite-tracking devices attached to sea turtles swimming off Florida's coast have delivered first-of-its-kind data that could help unlock they mystery of what endangered turtles do during the "lost years."
  • "lost years" refers to the time after turtles hatch and head to sea where they remain for many years before returning to near-shore waters as large juveniles
  • The time period is often referred to as the "lost years" because not much has been known about where the young turtles go and how they interact with their oceanic environment
  • ...22 more annotations...
  • "Before this study, most of the scientific information about the early life history of sea turtles was inferred through genetics studies, opportunistic sightings offshore, or laboratory-based studies
  • With real observations of turtles in their natural environment, we are able to examine and reevaluate existing hypotheses about the turtles' early life history
  • A team of scientists
  • tracked 17 loggerhead turtles for 27 to 220 days in the open ocean using small, solar-powered satellite tags
  • The goal was to better understand the turtles' movements, habitat preferences, and what role temperature may play in early sea turtle life history
  • While the turtles remain in oceanic waters (traveling between 124 miles to 2,672 miles) off the continental shelf and the loggerhead turtles sought the surface of the water as predicted
  • the study found that the turtles do not necessarily remain within the currents associated with the North Atlantic subtropical gyre
  • . It was historically thought that loggerhead turtles hatching from Florida's east coast complete a long, developmental migration in a large circle around the Atlantic entrained in these currents
  • the team's data suggest that turtles may drop out of these currents into the middle of the Atlantic or the Sargasso Sea.
  • The team also found that while the turtles mostly stayed at the sea surface, where they were exposed to the sun's energ
  • the turtles' shells registered more heat than anticipated (as recorded by sensors in the satellite tags
  • a new hypothesis about why the turtles seek refuge in Sargassum. It is a type of seaweed found on the surface of the water in the deep ocean long associated with young sea turtles.
  • propose that young turtles remain at the sea surface to gain a thermal benefit
  • "This makes sense because the turtles are cold blooded animals. By remaining at the sea surface,
  • by associating with Sargassum habitat, turtles gain a thermal refuge of sorts that may help enhance growth and feeding rates, among other physiological benefits.
  • More research will be needed, but it's a start at cracking the "lost years" myster
  • findings are important because the loggerhead turtles along with other sea turtles are threatened or endangered species
  • Florida beaches are important to their survival because they provide important nesting grounds in North America
  • More than 80% of Atlantic loggerheads nest along Florida's coast
  • There are other important nesting grounds and nursing areas for sea turtles in the western hemisphere found from as far north as Virginia to South America and the Caribbean.
  • "There's a whole lot that happens during the Atlantic crossing that we knew nothing abou
  • r work helps to redefine Atlantic loggerhead nursery grounds and early loggerhead habitat use
Mars Base

Mars rover Curiosity finds water in first sample of planet surface - 0 views

phys.org/...r-curiosity-sample-planet.html

scibyte104

shared by Mars Base on 27 Sep 13 - No Cached
  • The first scoop of soil analyzed by
  • Curiosity rover reveals
  • several percent water by weight
  • ...5 more annotations...
  • very first solid sample ingested by Curiosity is the high percentage of water in the soil
  • About 2 percent of the soil on the surface of Mars is made up of water
  • The sample also released significant carbon dioxide, oxygen, and sulfur compounds when heated
  • organics are not likely preserved in surface soils, which are exposed to harsh radiation and oxidants
  • layer of surface soil that has been mixed and distributed by frequent dust storms. So a scoop of this stuff is basically a microscopic Mars rock collection
Mars Base

May 2 - Today in Science History - Scientists born on May 2nd, died, and events - 0 views

todayinsci.com/5_02.htm

scibyte128 LookingBackMay

shared by Mars Base on 27 Apr 14 - No Cached
  • Electrolysis of water
  • In 1800, English chemist William Nicholson was the first to produce a chemical reaction by electricity. He had been working with Anthony Carlisle, a London surgeon, experimenting with Allesandro Volta's voltaic pile. The new effect was discovered when wires from the poles of the battery being used came into contact with water and bubbles of gas were released as current flowed through the water. Closer examination of the electrolysis showed oxygen was released at the (positive) anode, and hydrogen appeared at the cathode. Electricity had separated the molecules of water. Further, the effect of the amount of hydrogen and oxygen set free by the current was proportional to the amount of current used
  • Gulf Stream
  • ...1 more annotation...
  • In 1775, Benjamin Franklin completed the first scientific study of the Gulf Stream. His observations began in 1769 when as deputy postmaster of the British Colonies he found ships took two weeks longer to bring mail from England than was required in the opposite direction. Thus, Franklin became the first to chart the Gulf Stream
Mars Base

NASA - NASA Researchers Discover Ancient Microbes in Antarctic Lake - 0 views

www.nasa.gov/...12-408_Lake_Vida_Microbes.html

scibyte73 AntarcticLake

shared by Mars Base on 01 Dec 12 - No Cached
  • In one of the most remote lakes of Antarctica, nearly 65 feet beneath the icy surface, scientists
  • , have uncovered a community of bacteria
  • one of Earth's darkest, saltiest and coldest habitats
  • ...16 more annotations...
  • increase our limited knowledge of how life can sustain itself in these extreme environments on our own planet and beyond.
  • Lake Vida, the largest of several unique lakes found in the McMurdo Dry Valleys, contains no oxygen, is mostly frozen and possesses the highest nitrous oxide levels of any natural water body on Earth
  • approximately six times saltier than seawater
  • average temperature is minus 8 degrees Fahrenheit
  • the brine harbors a surprisingly diverse and abundant variety of bacteria that survive without a current source of energy from the sun
  • Previous studies of Lake Vida dating back to 1996 indicate the brine and its inhabitants have been isolated from outside influences for more than 3,000 years.
  • the best analog we have for possible ecosystems in the subsurface waters of Saturn's moon Enceladus and Jupiter's moon Europa
  • collaborators
  • developed stringent protocols and specialized equipment for their 2005 and 2010 field campaigns to sample from the lake brine while avoiding contaminating the pristine ecosystem
  • expands our knowledge of environmental limits for life and helps define new niches of habitability
  • To sample unique environments such as this, researchers must work under secure, sterile tents on the lake's surface
  • The tents kept the site and equipment clean as researchers drilled ice cores, collected samples of the salty brine residing in the lake ice and assessed the chemical qualities of the water and its potential for harboring and sustaining life
  • analyses suggest chemical reactions between the brine and the underlying iron-rich sediments generate nitrous oxide and molecular hydrogen
  • may provide the energy needed to support the brine's diverse microbial life.
  • Additional research is under way to analyze the abiotic, chemical interactions between the Lake Vida brine and its sediment
  • investigating the microbial community by using different genome sequencing approaches
Mars Base

NASA - Curiosity Rover Hits Paydirt - 0 views

www.nasa.gov/...curiosity20130315.html

scibyte86 Curiosity

shared by Mars Base on 17 Mar 13 - No Cached
  • This week the Curiosity science team released its initial findings from its first ever drilled sample on Mars
  • Curiosity obtained her first drill sample and passed that sample on to her onboard analytical lab instruments, called CheMin and SAM
  • These powerful instruments tell us about what minerals are present in these rocks and whether they contain the ingredients necessary to sustain life as we know it.
  • ...9 more annotations...
  • When we combine what we have learned from our remote sensing and contact science instruments with the data that's coming in from CheMin and SAM, we get a picture of an ancient watery environment, which would have been habitable had life been present in it.
  • the information that we're getting from the CheMin instrument, tells us that the minerals that are present in this lakebed sedimentary rock at John Klein are very different from just about anything we've ever analyzed before on Mars
  • they tell us that the John Klein rock was deposited in a fresh water environment
  • This is an important contrast with other sedimentary environments that we've visited on Mars, like the Meridiani Planum landing site where the Mars Exploration Rover, Opportunity, has been operating since 2004.
  • At that site, the sedimentary rocks record evidence of an environment that was only wet on a very intermittent basis, and when it was, the waters that were there were highly acidic, very salty, and not favorable for the survival of organic compounds.
  • direct contrast to the fresh water environment we're seeing here at the John Klein Site
  • The SAM instrument is telling us that these rocks contained all of the ingredients necessary for a habitable environment
  • We found carbon, sulfur and oxygen, all present and a number of other elements in states that life could have taken advantage of.
  • these few tablespoons of powder from a Martian rock have provided the Curiosity science team with an exciting new dataset
Mars Base

Hydrogen Peroxide Could Feed Life on Europa - 0 views

www.universetoday.com/...xide-could-feed-life-on-europa

scibyte89 Europa

shared by Mars Base on 06 Apr 13 - No Cached
  • According to research
  • Jupiter’s ice-encrusted moon Europa has hydrogen peroxide across much of the surface of its leading hemisphere
  • compound
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  • could potentially provide energy for life if it has found its way into the moon’s subsurface ocean.
  • The availability of oxidants like peroxide on Earth was a critical part of the rise of complex, multicellular life
  • The highest concentration of peroxide found was on the side of Europa that always leads in its orbit around Jupiter,
  • roughly 20 times more diluted than the hydrogen peroxide mixture available at drug stores
  • The concentration
  • then drops off to nearly zero on the hemisphere of Europa that faces backward in its orbit.
  • Hydrogen peroxide was first detected on Europa by NASA’s Galileo mission, which explored the Jupiter system from 1995 to 2003
  • Galileo observations were of a limited region. The new Keck data show that peroxide is widespread across much of the surface of Europa, and the highest concentrations are reached in regions where Europa’s ice is nearly pure water with very little sulfur contamination
  • scientists think hydrogen peroxide is an important factor for the habitability of the global liquid water ocean under Europa’s icy crust
  • hydrogen peroxide decays to oxygen when mixed into liquid water
  • abundant compounds like peroxide could help to satisfy the chemical energy requirement needed for life within the ocean, if the peroxide is mixed into the ocean
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