Here we are one more time. Monday arrived right on schedule. Science talk returns to brighten your day with selections from science sites across the globe. New discoveries, new takes on old knowledge, and other bits of news are all available for the perusing in today's information world. Today's tidbits include NASA's WISE survey uncovers millions of black holes, there may be large methane reservoirs beneath the Antarctic ice sheet, shading Earth could combat global warming, development of a new and less expensive nanolithography method, and 'nanoresonators' might improve cell phone function.
Pull up that comfy chair and grab a spot on the porch. There is always plenty of room for everyone. Another session of Dr. Possum's science education, entertainment, and potluck discussion is set to begin.
Featured Stories
Large numbers of black holes and hot DOGS (dust-obscured galaxies) are the result of NASA's WISE (Wide-field Infrared Survey Explorer) mission.
WISE scanned the whole sky twice in infrared light, completing its survey in early 2011. Like night-vision goggles probing the dark, the telescope captured millions of images of the sky. All the data from the mission have been released publicly, allowing astronomers to dig in and make new discoveries.
The latest findings are helping astronomers better understand how galaxies and the behemoth black holes at their centers grow and evolve together. For example, the giant black hole at the center of our Milky Way galaxy, called Sagittarius A*, has 4 million times the mass of our sun and has gone through periodic feeding frenzies where material falls towards the black hole, heats up and irradiates its surroundings. Bigger central black holes, up to a billion times the mass of our sun, may even shut down star formation in galaxies.
Old organic matter beneath the Antarctic ice sheet may be an important reservoir of
methane.
The science team estimated that 50 percent of the West Antarctic Ice Sheet (1 million square kilometers) and 25 percent of the East Antarctic Ice Sheet (2.5 million square kilometers) overlies pre-glacial sedimentary basins containing about 21,000 billion metric tons of organic carbon.
"This is an immense amount of organic carbon, more than ten times the size of carbon stocks in northern permafrost regions," (researcher) Wadham said. "Our laboratory experiments tell us that these sub-ice environments are also biologically active, meaning that this organic carbon is probably being metabolized to carbon dioxide and methane gas by microbes."
The transport of materials into space to
shade Earth and slow global warming may be both possible and affordable according to researchers.
Based on existing research into solar radiation management, the researchers performed their cost analyses for systems that could deliver around one million tonnes of aerosols each year at an altitude between 18 and 25 km and between a latitude range of 30°N and 30°S.
The study concluded that using aircraft is easily within the current capabilities of aerospace engineering, manufacturing and operations. The development of new, specialized aircraft appeared to be the cheapest option, with costs of around $1 to $2 billion a year; existing aircraft would be more expensive as they are not optimized for high altitudes and would need considerable and expensive modifications to do so.
Guns and rockets appeared to be capable of delivering materials at high altitudes but the costs associated with these are much higher than those of airplanes and airships due to their lack of reusability.
One use of
nanolithography is in the development of microchips for biological sensors. A new method promises both an easier and less expensive method.
The new technique relies on cantilevers, which are 150-micron long silicon strips. The cantilevers can be tipped with spheres made of polymer or with naturally occurring spores. The spheres and spores are coated with ink and dried. The spheres and spores are absorbent and will soak up water when exposed to increased humidity.
As a result, when the cantilevers are exposed to humidity in a chamber, the spheres and spores absorb water – making the tips of the cantilevers heavier and dragging them down into contact with any chosen surface.
Users can manipulate the size of the spheres and spores, which allows them to control the patterns created by the cantilevers. For example, at low humidity, a large sphere will absorb more water than a small sphere, and will therefore be dragged down into contact with the substrate surface. The small sphere won’t be lowered into contact with the surface until it is exposed to higher humidity and absorbs more water.
'Nanoresonators,' a class of tiny mechanical devices, may one day help filter cell phone signals to allow better functions in terms of few dropped calls and higher speed data transmission.
The devices are created using silicon-on-insulator, or SOI, fabrication - the same method used by industry to manufacture other electronic devices. The resonators can be readily integrated into electronic circuits and systems because SOI is compatible with complementary metal–oxide–semiconductor technology, or CMOS, another mainstay of electronics manufacturing used to manufacture computer chips.
The resonators are in a class of devices called nanoelectromechanical systems, or NEMS.
The new device is said to be "highly tunable," which means it could enable researchers to overcome manufacturing inconsistencies that are common in nanoscale devices.
Knucklehead's Photo of the Week
Marine Betta
©Knucklehead, all rights reserved, presented by permission. (Click on the image to see more in the same series.)
Other Worthy Stories of the Week
Astronomers find double planet, double star system
A new theory for Moon formation
'Penis-head' fish discovered in Vietnam
Building blocks of life found around a young star
New video shows huge eruption on the Sun
Genome brings ancient girl to life
Space warping white dwarfs produce gravitational waves
First implantation of prototype bionic eye
Hubble spotted a supernova in NGC 5806
Glass shape influences how quickly we drink alcohol
Hidden graves of the Holocaust
Arctic sea ice reaches the lowest extent ever recorded
Why are there so many species of beetles and so few crocodiles?
For even more science news:
General Science Collectors:
Alpha-Galileo
BBC News Science and Environment
Eureka Science News
LiveScience
New Scientist
PhysOrg.com
SciDev.net
Science/AAAS
Science Alert
Science Centric
Science Daily
Scientific American
Space Daily
Blogs:
A Few Things Ill Considered Techie and Science News
Cantauri Dreams space exploration
Coctail Party Physics Physics with a twist.
Deep Sea News marine biology
Laelaps more vertebrate paleontology
List of Geoscience Blogs
ScienceBlogs
Space Review
Techonology Review
Tetrapod Zoologyvertebrate paleontology
Science Insider
Scientific Blogging.
Space.com
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
At Daily Kos:
This Week in Science by DarkSyde
Overnight News Digest:Science Saturday by Neon Vincent. OND tech Thursday by rfall.
Pique the Geek by Translator Sunday evenings about 9 Eastern time
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
A More Ancient World by matching mole
Astro Kos
SciTech at Dkos.
Sunday Science Videos by palantir
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive
Doradus Nebula, NASA, Public Domain