and more efficient at harvesting energy from the sun. For solar panels wringing every drop of energy from as many photons as possible is imperative.
and most of the energy from the sun is in the visible and infrared spectrum. â#Finding a material that exhibits the bulk photovoltaic effect for visible light would greatly simplify solar cell construction.
Moreover it would be a way around an inefficiency intrinsic to interfacial solar cells known as the Shockley-Queisser limit where some of the energy from photons is lost as electrons wait to make the jump from one material to the other. hink of photons coming from the sun
and earth-abundant elements unlike compound semiconductor materials currently used in efficient thin-film solar cell technology. he research was supported by the Energy Commercialization Institute of Ben Franklin Technology Partners the Department of energy's Office of Basic Sciences
MKIDS were developed first a decade ago by Mazin his Ph d. adviser Jonas Zmuidzinas professor of physics at the California Institute of technology and Henry Leduc at NASA s Jet propulsion laboratory.
MKIDS are used in astronomy for taking measurements across the electromagnetic spectrum. In his lab at UC Santa barbara Mazin has adapted these detectors for the ultraviolet optical and near-IR parts of the spectrum.
MKIDS which operate at cryogenic temperatures (typically 0. 1 Kelvin) allow astronomers to determine the energy
and arrival time of individual photons. orty years ago we were doing optical astronomy with photographic plates
but not all applications. or observations of rare objects like optical pulsars and high redshift galaxies ARCONS small field of view (20 arc seconds by 20 arc seconds
This allows astronomers to see rapidly changing events a great advantage for many observations. MKIDS have inherent frequency domain multiplexing capabilities
Mazin and his team lens-coupled a 2024-pixel array to the Palomar 200-inch and the Lick 120-inch telescopes in Southern California and Northern California respectively.
ARCONS was on these telescopes for 24 observing nights during which data was collected on optical pulsars compact binaries high redshift galaxies and planetary transits.
RCONS is very sensitive but it s been coupled with 5-meter telescopesmazin says. he 8-to 10-meter telescopes such as Keck are at better sites with four times the collecting area. e hope to deploy MKID instruments in the next several
years at Keck and other telescopes to make fascinating new observations including using MKIDS coupled to a coronagraph to directly discover
and take spectra of planets around nearby stars. Source: UC Santa Barbar
#Wireless device grabs lost energy from Wi-fi Using inexpensive materials configured and tuned to capture microwave signals researchers have designed a power harvesting device with efficiency similar to that of modern solar panels.
The device wirelessly converts the microwave signal to direct current voltage capable of recharging a cell phone battery or other small electronic device according to a report appearing in Applied Physics Letters.
or example a series of power harvesting blocks could be assembled to capture the signal from a known set of satellites passing overhead the researchers explain.
If you think about the beauty of an egg yolk there is some empty space inside with space for the yolk to expandyu says.
The component converts heat from the sun into infrared light which can be absorbed by solar cells to make electricity a technology known as thermophotovoltaics.
A typical solar cell has a silicon semiconductor that absorbs sunlight directly and converts it into electrical energy.
Instead of sending sunlight directly to the solar cell thermophotovoltaic systems have an intermediate component that consists of two parts:
an absorber that heats up when exposed to sunlight and an emitter that converts the heat to infrared light
Land-based wireless networks rely on radio waves that transmit data via satellites and antennae. Unfortunately radio waves work poorly underwaterâ
The buoys convert the acoustic waves into radio waves to send the data to a satellite which then redirects the radio waves back to land-based computers.
#Signs of water detected in exoplanet s debris University of Warwick rightoriginal Studyposted by Anna Blackaby-Warwick on October 11 2013the remains of a water-rich rocky exoplanet have been discovered outside
our solar system orbiting a white dwarf star 170 light years away. Using observations obtained with the Hubble Space Telescopeâ
and the large telescopes of the W. M. Keck Observatory researchers found an excess of oxygenâ##a chemical signature that indicates that the debris had once been part of a bigger body originally composed of 26 percent water by mass.
By contrast only approximately 0. 023 percent of the Earth s mass is water. Evidence for water outside our solar system has previously been found in the atmosphere of gas giants
but this is the first time it has been pinpointed in a rocky body making it of significant interest in understanding of the formation and evolution of habitable planets and life.
The dwarf planet Ceres contains ice buried beneath an outer crust and researchers have drawn a parallel between the two bodies.
Itâ#believed that bodies like Ceres were the source of the bulk of our own water On earth.
In the study published in Science researchers suggest it is most likely that the water detected around the white dwarf GD 61 came from a minor planet at least 90 kilometers (56 miles) in diameterâ
##but potentially much biggerâ##that once orbited the parent star before it became a white dwarf.
Like Ceres the water was most likely in the form of ice below the planet s surface.
From the amount of rocks and water detected in the outer envelope of the white dwarf the researchers estimate that the disrupted planetary body had a diameter of at least 90 kilometers.
However because their observations can only detect what is being accreted in recent history the estimate of its mass is on the conservative side.
It is likely that the object was as large as Vesta the largest minor planet in the solar system.
In its former life GD 61 was a star somewhat bigger than our Sun and host to a planetary system.
About 200 million years ago GD 61 entered its death throes and became a white dwarf yet parts of its planetary system survived.
The water-rich minor planet was knocked out of its regular orbit and plunged into a very close orbit where it was shredded by the starâ#gravitational force.
Researchers believe that destabilizing the orbit of the minor planet requires a so far unseen much larger planet going around the white dwarf. t this stage in its existence all that remains of this rocky body is simply dust
and debris that has been pulled into the orbit of its dying parent starâ#says Boris Gänsicke professor of physics at the University of Warwick. owever this planetary graveyard swirling around the embers of its parent star is a rich source
of information about its former life. Â In these remnants lie chemical clues which point towards a previous existence as a water-rich terrestrial body. hose two ingredientsâ##a rocky surface
and waterâ##are key in the hunt for habitable planets outside our solar system so itâ#very exciting to find them together for the first time outside our solar system.?
The finding of water in a large asteroid means the building blocks of habitable planets existedâ ##and maybe still existâ##in the GD 61 system and likely also around substantial number of similar parent starssays lead author Jay Farihi from the Institute of Astronomy at the University of Cambridge. hese water-rich building blocks
and the terrestrial planets they build may in fact be commonâ##a system cannot create things as big as asteroids
and avoid building planets and GD 61 had the ingredients to deliver lots of water to their surfaces. ur results demonstrate that there was definitely potential for habitable planets in this exoplanetary system
. or their analysis the researchers used ultraviolet spectroscopy data obtained with the Cosmic Origins Spectrograph on board the Hubble space telescope of the white dwarf GD 61.
As the atmosphere of the Earth blocks the ultraviolet light such study can only be carried out from space.
Additional observations were obtained with both of the 10m telescopes of the W. M. Keck Observatory on the summit of Mauna kea Hawaii.
The Hubble and Keck data allows the researchers to identify the different chemical elements that are polluting the outer layers white dwarf.
Using a sophisticated computer model of the white dwarf atmosphere developed by Detlev Koester at the University of Kiel they were able to infer the chemical composition of the shredded minor planet.
To date observations of 12 destroyed exoplanets orbiting white dwarves have been carried out but this is the first time the signature of water has been found.
Source: University of Warwickyou are free to share this article under the Creative Commons Attribution-Noderivs 3. 0 Unported license h
#rtificial nose detects dangerous vapors Researchers have developed a way to sniff out solvent gases by combining a common mineral zeolite with a metallic compound based on rhenium.
They report that in the presence of the compound each gas has a photoluminescent ingerprintwith a specific intensity lifetime and color.
The challenge for Angel Mart assistant professor of chemistry and bioengineering at Rice university and his team of student researchers was to get their large metallic particles through the much smaller pores of a zeolite cage.
and gases can t interact with themhe says. o we started thinking of ways to create space between them. nter zeolites. hese zeolites are cages with big cavities
or search for such formations on Mars and other planets to determine where water once existed.
They take almost no space at all. ther researchers from Rice university the University of Texas at Austin Oak ridge National Laboratory
First they are boosted to nearly the speed of light. Then any additional acceleration increases their energy but not their speed;
and generate more heatâ##all in a smaller and smaller space as evidenced by the warmth emanating from the bottom of a laptop.
These deep earthquakes occur in older and colder areas of the oceanic plate that gets pushed into the earth s mantle.
because seismologists could not find a seismic signal in the Earth that could confirm the results.
The ability to do such experiments allows scientists like Green to simulate the appropriate conditions within the Earth
and found the arthquakesonly within a narrow temperature range that simulates conditions where the real earthquakes occur in Earth. sing synchrotron X-rays to aid our observations we found that fractures nucleate at the onset of the olivine to spinel transitiongreen says. urther these fractures propagate dynamically
#Densest galaxy is jam-packed with stars Michigan State university right Original Studyposted by Tom Oswald-Michigan State on September 25 2013 Astronomers have discovered the densest galaxy in the nearby universe.
The stars are about 25 times closer than those in the Milky way. Imagine the distance between the sun and the star nearest to itâ##a star called Alpha centauri.
That's a distance of about 4 light years. Now imagine as many as 10000 of our suns crammed into that relatively small space. his galaxy is more massive than any ultra-compact drawfs of comparable sizesays Jay Strader assistant professor of physics
and astronomy at Michigan State university nd is arguably the densest galaxy known in the local universe. s detailed in the recent edition of the publication Astrophysical Journal Letters the ultra-compact dwarf galaxy was found in near
the massive elliptical galaxy NGC 4649 also called M60 about 54 million light years from Earth.
What makes this galaxy dubbed M60-UCD1 so remarkable is that about half of its mass is found within a radius of only about 80 light years.
This would make the density of stars about 15000 times greater than that found in Earth's neighborhood in the Milky way. raveling from one star to another would be a lot easier in M60-UCD1 than it is in our galaxystrader says. ince the stars are so much closer in this galaxy
it would take just a fraction of the time. he discovery of ultra-compact galaxies is relatively newâ##only within the past 10 years or so.
Until then astronomers could see these hingsway off in the distance but assumed they were either single stars or very-distant galaxies.
Another intriguing aspect of this galaxy is the presence of a bright X-ray source in its center.
One explanation for this is a giant black hole weighing in at some 10 million times the mass of our sun. Astronomers are trying to determine
if M60-UCD1 and other ultra-compact dwarf galaxies are born either as really jam-packed star clusters or if they are galaxies that get smaller
because they have ripped stars away from them. The possible massive black hole combined with the high galaxy mass and sun-like levels of elements found in the stars favor the latter idea.
A giant black hole at the center of M60-UCD1 helps tip the scales against the scenario where this galaxy was once a star cluster
since such large black holes are not found in these types of objects. The galaxy was discovered using NASA's Hubble space telescope.
Follow-up observations were done with NASA's Chandra X-ray Observatory and ground-based optical telescopes including the Keck 10-meter telescope in Hawaii. wenty years ago we couldn't have done thisstrader says. e didn't have Hubble or Chandra.
This is one of those projects where you bring together the full force of NASA's great observatories plus ground-based resources. ource:
Michigan State Universityyou are free to share this article under the Creative Commons Attribution-Noderivs 3. 0 Unported license u
#Colonies of wired microbes turn sewage into electricity Stanford university rightoriginal Studyposted by Tom Abate-Stanford on September 19 2013a new way to generate electricity from sewage uses naturally occurring ired microbesas mini power plants
to produce electricity as they digest plant and animal waste. Scientists hope the icrobial batterycan be used in places such as sewage treatment plants
or to break down organic pollutants in the ead zonesof lakes and coastal waters where fertilizer runoff and other organic waste can deplete oxygen levels
and suffocate marine life. At the moment however the laboratory prototype is about the size of A d-cell battery
and looks like a chemistry experiment with two electrodes one positive the other negative plunged into a bottle of wastewater.
Inside that murky vial attached to the negative electrode bacteria feast on particles of organic waste
and produce electricity that is captured by the battery s positive electrode. e call it fishing for electronssays Craig Criddle a professor in the department of civil and environmental engineering at Stanford university.
That is roughly the same efficiency at which the best commercially available solar cells convert sunlight into electricity.
#Earth s inner core spins faster than rest of planet University of Leeds rightoriginal Studyposted by Ben Jones-U. Leeds on September 17 2013the Earth s
Although Edmund Halley who also discovered the famous comet showed the westward-drifting motion of the Earth s geomagnetic field in 1692 it is the first time that scientists have been able to link the way the inner core spins to the behavior of the outer core.
The planet behaves in this way because it is responding to the Earth s geomagnetic field.
The findings published in the Proceedings of the National Academy of Sciences help scientists to interpret the dynamics of the core of the Earth the source of our planet s magnetic field.
In the last few decades seismometers measuring earthquakes travelling through the Earth s core have identified an eastwards
or superrotation of the solid inner core relative to Earth s surface. he link is explained simply in terms of equal and opposite actionsays Philip Livermore of the School of Earth
and Environment at the University of Leeds. he magnetic field pushes eastwards on the inner core causing it to spin faster than the Earth
but it also pushes in the opposite direction in the liquid outer core which creates a westward motion. he solid iron inner core is about the size of the Moon.
It is surrounded by the liquid outer core an iron alloy whose convection-driven movement generates the geomagnetic field.
The fact that the Earth s internal magnetic field changes slowly over a timescale of decades means that the electromagnetic force responsible for pushing the inner and outer cores will itself change over time.
The authors used a model of the Earth s core that was run on the giant supercomputer Monte Rosa part of The swiss National Supercomputing Centre in Lugano Switzerland.
Using a new method they were able to simulate the Earth s core with an accuracy about 100 times better than other models.
#Earth s wobble fixes food for ocean creatures Princeton university rightoriginal Studyposted by Catherine Zandonella-Princeton on September 16 2013the cyclic wobble of the Earth on its axis controls the production of ixednitrogen
and fell in a pattern that closely matched the changing orientation of Earth s axis of rotation or axial precession.
and arises because the Earth wobbles slightly as it rotates similar to the wobble of a toy top.
and geophysical sciences at Princeton university. y studying the response of nitrogen fixation to different environmental changes in the Earth s past we have found connections that may ensure that the ocean s fixed nitrogen level will always reboundsigman says. his suggests that an ocean over time has a relatively stable nutrient reservoir
Some of the work was carried out at the Jet propulsion laboratory under a contract with NASA and the Kavli Nanoscience Institute at Caltech provided support and infrastructure.
and robust performance on virtually all surfaces. n aerospace company has expressed already interest in furthering thes technology.
and in space. ur intention is to completely move away from conventional liquid or gel-type electrolytes,
#Ice may explain odd craters on Mars Brown University right Original Studyposted by Kevin Stacey-Brown on August 6 2013brown (US) More than 600 double-layer craters on Mars may have been caused by debris
These distinctive craters were documented first in data returned from the Viking missions to Mars in the 1970s
Recent discoveries by planetary geoscientists at Brown and elsewhere have shown that the climate of Mars has varied in the past says James W. Head professor of geological science at Brown University.
During these times ice from the polar caps is redistributed into the mid-latitudes of Mars as a layer about 50 meters thick in the same place that we see that the DLES have formed.
or high latitudes areas where scientists believe there may once have been glacial ice on Mars. Ultimately understanding how DLES
and other crater types are formed could lead to a better understanding of Mars past. There are over 600 DLES on the Martian surface
so reconciling how they formed with our knowledge of the climate of Mars is pretty important Weiss says.
NASA supported the work. Source: Brown University you are free to share this article under the Creative Commons Attribution-No Derivs 3. 0 Unported license c
maintaining the minute space between the graphene sheets and conducting electricity. Unlike in traditional#hard#porous carbon where space is wasted with unnecessarily large pores density is maximized without compromising porosity in Li s electrode.
To create their material the research team used a method similar to that used in traditional paper making meaning the process could be easily
Maurizio Porfiri associate professor of mechanical and aerospace engineering at the Polytechnic institute of New york University (NYU-Poly) and Simone Macr##a collaborator at the Istituto Superiore di Sanit##in Rome Italy published their findings
#This discovery of electron neutrino appearance from muon neutrinos by the T2k experiment opens another critical door in our journey to unveil the secrets of our universe.#
because it could help explore a fundamental question of science#why is made the universe up almost exclusively of matter
when matter and antimatter were created in equal amounts in the Big bang? Somehow this balance changed over time to a dominance of matter.
##Solar steam kills germs while off the grid RICE (US) A new sterilization system uses nanomaterials to convert 80 percent of the energy in sunlight into heat,
director of the Laboratory for Nanophotonics (LANP) at Rice university. olar steam efficiency at converting sunlight directly into steam opens up new possibilities for off-grid sterilization that simply aren available today In a previous study last year,
Halas and colleagues showed that olar steamwas so effective at direct conversion of solar energy into heat that it could even produce steam from ice water. t makes steam directly from sunlight,
and exposed to sunlight, the particles heat up so quickly they instantly vaporize water and create steam.
#New evidence suggests giant ocean on Mars CALTECH (US) esearchers have found signs of an ancient delta on Mars where a river might have emptied once into a vast ocean.
could have covered much of Mars northern hemispheretretching over as much as a third of the planet. cientists have hypothesized long that the northern lowlands of Mars are a dried-up ocean bottom,
Most of the northern hemisphere of Mars is flat and at a lower elevation than the southern hemisphere,
Researchers used new high-resolution images from the Mars Reconnaissance Orbiter (MRO) to study a 100-square-kilometer area that sits right on this possible former coastline.
Previous satellite images have shown that this areaart of a larger region called Aeolis Dorsa which is about 1,
000 kilometers away from Gale crater where the Curiosity rover is now roamings covered in ridge-like features called inverted channels.
By taking pictures from different points in its orbit, the spacecraft was able to make stereo images that have allowed scientists to determine the topography of the martian surface.
of Mars, says Dibiase, lead author of the paper published in the Journal of Geophysical Research.
This large body of water could be the ocean that has been hypothesized to have covered a third of the planet.
and that of othersncluding the Curiosity rovercientists are finding a rich sedimentary record on Mars that is revealing its past environments,
and potentially oceans, Lamb says. oth the ancient environments on Mars and the planet sedimentary archive of these environments are turning out to be surprisingly Earthlike.
This research was supported by the National Science Foundation NASA, and Caltech
#Graphene#s jagged edge can easily slice cells Brown University right Original Study Posted by Kevin Stacey-Brown on July 10 2013brown (US) the jagged edges of tiny graphene sheets
can spell trouble for human cells. New research shows the sharp edges can puncture cell membranes.
a science fiction idea of a space elevator that could connect an orbiting satellite to Earth by a long cord that might consist of sheets of CVD graphene,
and Exploration Science Directorate NASA/Johnson Space center notes that the spindles appear to be the same as those found in rocks from the Strelly Pool Formation in Western australia
The NASA Astrobiology Institute the Astromaterials Research and Exploration Science Directorate Johnson Space center and the Japan Society for the Promotion of Science supported this research.
#One of the major advantages of robotics is that we can provide a fully controllable consistent stimulus for the zebrafish#says Maurizio Porfiri associate professor of mechanical and aerospace engineering at the Polytechnic institute of New york University (NYU-Poly.#
#It is one of the most durable construction materials on the planet and that was no accident.
#Earth-friendly alternativewhile Roman concrete is durable it#s unlikely to replace modern concrete because it is not ideal for construction where faster hardening is needed.
But the researchers are now finding ways to apply their discoveries about Roman concrete to the development of more earth-friendly and durable modern concrete.
we use the hurricane to take us places#says Kamran Mohseni professor in the department of mechanical and aerospace engineering and the department of electrical and computer engineering at the University of Florida.
##Dynamo accounts for Sun s weather cycle University of Chicago University of Leeds rightoriginal Studyposted by Richard Mellor-Leeds on May 23 2013u.
what drives the generation of astrophysical magnetic fields like the Sun s. Scientists have known since the 18th century that the Sun regularly oscillates between periods of high and low solar activity in an 11-year cycle
but have been unable to fully explain how this cycle is generated. It has become increasingly important to be able to understand the Sun#s magnetic activity as it is the changes in its magnetic field that are responsible for#space weather#phenomena including solar flares and coronal mass ejections.
When this weather heads in the direction of Earth it can damage satellites endanger astronauts on the International space station and cause power grid outages on the ground.
The research published in Nature explains how the cyclical nature of these large-scale magnetic fields emerges providing a solution to the mathematical equations governing fluids and electromagnetism for a large astrophysical body.
which makes up the Sun. More importantly it does so in the extreme parameter regime that is relevant to astrophysical bodies.#
#Previously dynamos for large highly conducting bodies such as the Sun would be overwhelmed by small-scale fluctuations in the magnetic field.
In addition this mechanism could be used to describe other large spinning astronomical bodies with large-scale magnetic fields such as galaxies.
and huge supercomputers shows how complicated the dynamo process really is#says Professor Fausto Cattaneo of the University of Chicago#s department of astronomy and astrophysics.
The presence of spots on the Sun has been known since antiquity and further analyzed after the invention of the telescope by Galileo in the 16th century.
However their cyclic nature with periods of high activity (lots of sunspots) and low activity (few sunspots) following each other was identified not until the 18th century.
At the start of the 20th century it was recognized then that these sunspots were the result of the Sun#s magnetic field.
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