Thursday, December 30, 2010

NASA Invests in Earth Observation




Artist's concept of the Glory spacecraft in orbit. Credit: NASA

Strong support from the White House and U.S. Congress will allow NASA to lay the groundwork for a vigorous and extensive Earth science program that includes 16 major missions scheduled for launch between 2011 and 2021, an agency official said.
 
"What a difference a year makes," Michael Freilich, director of NASA's Earth Science Division, said this month at a meeting of the American Geophysical Union here. "Last year things were a little bit dicey. This year we are moving forward rather dramatically." 

In contrast to late 2009 when NASA's Earth Science Division faced growing demands in spite of constrained funding, the current five-year spending plan provides the division with an additional $2.4 billion over the previous budget blueprint, Freilich said. 

If approved by Congress, that money will allow NASA "to go from flying one mission every couple of years to flying a couple of missions per year," he said.

NASA SOHO Image: 2,000th Comet spotted




SOHO's 2,000th comet, spotted by a Polish amateur astronomer on Dec. 26, 2010. 

Credit: SOHO/Karl Battams 

As people on Earth prepare to mark the passage of another year, a sun-studying spacecraft has quietly reached a big milestone of its own: discovering its 2,000th comet.
The Solar and Heliospheric Observatory, a probe operated jointly by NASA and the European Space Agency, detected comet No. 2,000 on Dec. 26. SOHO, which draws on help from citizen scientists around the world, is the single greatest comet-finder of all time, researchers said.
This is an impressive show of versatility, since SOHO was designed to monitor the sun, not look for comets.
"Since it launched on December 2, 1995, to observe the sun, SOHO has more than doubled the number of comets for which orbits have been determined over the last 300 years," Joe Gurman, the U.S. project scientist for SOHO at NASA's Goddard Space Flight Center in Greenbelt, Md., said in a statement.

NASA WISE Image: Flaming Star Nebula




An image of the Flaming Star Nebula, taken in infrared light by NASA's WISE space telescope.

Credit: NASA/JPL-Caltech/WISE Team

The new pictures from WISE — short for Wide-field Infrared Survey Explorer, which launched on Dec. 14, 2009 — are dramatic, colourful images of interstellar clouds of gas and dust called nebulas.
The first photo depicts a structure known as the Flaming Star Nebula, which is about 1,500 light-years away in the constellation Auriga.

At the nebula's heart is the star AE Aurigae, which appears to be ablaze, hence the name.
AE Aurigae is a so-called runaway star, researchers said. It was likely born in the Trapezium Cluster, in the constellation Orion, but was booted out by a collision with a binary star system about 2.5 million years ago.
The enhanced colours seen in the image represent specific wavelengths of infrared light, which unaided human eyes cannot see. 

Hot stars scattered throughout the nebula show up as blue and cyan. Glowing gas appears green, while heated-up dust is primarily red, researchers said.

ESA Fails to endorse ISS extension

The European Space Agency (ESA) was unable to win its member governments' approval of NASA's proposed five-year extension of operations of the International Space Station because of an unrelated dispute over financial support for EuropeÕs Arianespace commercial launch services consortium, ESA and European government officials said. 
 
As a result, no decision approving the station's extension to 2020 will be made before a March meeting of ESA governments. ESA already is committed to supporting the station through 2015, though the details remain to be worked out.

Meeting in its habitual closed-door session Dec. 15-16, ESA's ruling council issued a statement expressing general approval for the station's continued use, and also backing further support for Arianespace. 

The resolution produced during the meeting makes no specific reference to Evry, France-based Arianespace's request for 240 million euros ($324 million) over two years to offset certain fixed costs of its business at its suppliers' factories in Europe and at the Guiana Space Center spaceport in French Guiana. 

Antonio Fabrizi, ESA's director of launchers, said the agency views Arianespace's request for 120 million euros per year in support as "a kind of ceiling. We will now examine the request in detail and report to our council in March on our conclusions. But our member states are generally in favor of some support. What remains is an examination of what the level of support should be."

Russian President Reprimands RSA

Russian President Dmitry Medvedev has formally reprimanded the chief of his country's national space agency and fired two other high-ranking space officials over the loss of three state-of-the-art navigation satellites in a botched rocket launch earlier this month.

The decision, announced by the Kremlin today (Dec. 29), comes after an investigation into the Dec. 5 launch failure of a Russian-built Proton rocket carrying three new Glonass-M navigation satellites.

The satellites never reached orbit. Instead, they plunged back to Earth and crashed in the Pacific Ocean north of Hawaii.

Inactive 'Zombie' satellite comes to life




The Galaxy 15 satellite is seen before its 2005 launch to geostationary orbit nearly 36,000 kilometers over the Earth's equator. 

Credit: Orbital Sciences

The Galaxy 15 communications satellite lost contact with its flight control center in April. But in an unexpected twist, the stricken satellite's telecommunications broadcast package remained in operation. 

With Intelsat operators unable to control the solar-powered satellite, Galaxy 15 continued to transmit signals, posing a risk of interfering with the signals of neighbouring satellites


In the months that followed, Intelsat worked closely with the operators of other broadcast satellites to ensure that their communications services – which included television broadcasts – would not be affected when Galaxy 15 drifted by. But that drama in space has ended.

On Dec. 23, the battery on Galaxy 15 — which relied on solar panels pointed at the sun to generate power — became completely drained, Intelsat officials said. Once that happened, the satellite reset itself as designed and began accepting commands from Intelsat's control centre.

"We have placed Galaxy 15 in safe mode, and at this time, we are pleased to report it no longer poses any threat of satellite interference to either neighboring satellites or customer services," Intelsat officials announced.

Arianespace Ariane 5 launch




An Arianespace Ariane 5 rocket soars from a launch pad at the Guiana Space Center Kourou, French Guiana on Dec. 29, 2010, carrying two new communications satellites for different customers. 

It was the sixth and last Ariane 5 rocket launch of 2010, and the last rocket launch of the year. 

Credit: Arianespace

The heavy-lift launcher, making its 55th flight, climbed steeply through the late afternoon sky and headed downrange for a half-hour trek into geosynchronous transfer orbit to deliver the Spanish Hispasat 1E and South Korea's Koreasat 6 spacecraft.

Friday, December 24, 2010

Ben Goldacre Video: Bad Science Kills

CLICK on the picture to play the video

Here's Ben "Bad Science" Goldacre presenting on how non-evidence-based medicine can kill you and thousands of your friends.

Ben's book, titled Bad Science, is great as well, and it comes highly recommended.

He had to take out a chapter to avoid litigation by Mathias Rath, who travelled to South Africa and widely publicised claims that vitamins can cure AIDS. This fell into line with the South African AIDS denialists.

Ben posted that chapter on his website, and it may be one of the most important things ever written in the area of critical thinking. Lack of responsible treatment for AIDS kills hundreds of thousands of people in Africa alone.

When people like Ben win, lives are saved. The more people who know about him, the better. He's a true hero of skepticism.

Thursday, December 23, 2010

Solar Simulator: Reactor could make fuel from solar energy and CO2

SolarSimulator.jpg

(Image: Aldo Steinfield/Swiss Federal Institute of Technology)

Imagine filling up your car on an environmentally-friendly fuel produced from sunlight, water and carbon dioxide from the air.

That goal may now be a step closer following successful tests of a new solar-powered reactor.

Researchers around the world have recently been experimenting with different catalysts capable of producing hydrocarbon fuels from water and carbon dioxide when heated by concentrated sunlight.

Such a fuel would not only reduce greenhouse gas emissions, but could be used with little change to our existing cars and infrastructure.

Now William Chueh at the California Institute of Technology in Pasadena and colleagues have developed a reactor that uses cerium oxide as a catalyst. Cerium oxide is an abundant material suitable for commercial-scale fuel production, but it hadn't been demonstrated in a reactor under realistic conditions.

In Chueh's reactor, concentrated solar energy enters the chamber through a window. Once inside the chamber, the sunlight is reflected several times to capture as much of the solar energy as possible. It is used to heat a 35 millimetre-diameter cylinder of cerium oxide to around 1500 degrees Celsius. This causes the cerium to release an oxygen atom.

The temperature in the chamber is then reduced to around 900 degrees Celsius, and carbon dioxide is pumped into the chamber through an inlet. The cerium grabs an oxygen atom from the carbon dioxide to replace the one that it has lost, producing carbon monoxide and cerium oxide.

The carbon monoxide is then removed from the chamber, which is heated back up to 1500 degrees Celsius and the whole cycle is repeated.

The same process is also used to generate hydrogen from steam. The team has successfully run the process to produce the two gases in over 500 cycles.

The efficiency of the device is low, at around 0.4 per cent, but much of this is due to heat loss through the reactor walls and aperture, which can be dealt with through improvements to the device's insulation and design, the team say. Efficiencies of up to 19 per cent should then be possible, they add.

Carbon monoxide and hydrogen can be converted into a synthetic liquid using a technique such as the Fischer-Tropsch process, in which they are heated in the presence of an iron-based catalyst to produce hydrocarbon fuels.

Ultimately, such plants could use carbon dioxide from the air to produce fuel. Team member Aldo Steinfeld at the Swiss Federal Institute of Technology, Zurich, has already demonstrated that a similar process can be used to remove CO2 from the atmosphere.

He and his team used concentrated sunlight to heat calcium oxide to 400 degrees Celsius, causing it to react with CO2 in the air to form calcium carbonate. When heated again, this time to 800 degrees Celsius, the calcium carbonate releases a pure stream of CO2 that can then be used in the solar fuel reactor.

Journal reference: Science, DOI: 10.1126/science.1197834

Our Universe is one of many




Some researchers think concentric ring patterns in measurements of the cosmic microwave background are evidence of a universe that existed before our own was born in the Big Bang. 

Credit: Roger Penrose and Vahe Gurzadyan


The evidence in question is said to lie in the haze of microwaves permeating the cosmos that was left over after the Big Bang.

This light, and patterns within it, has granted scientists a picture of the earliest years of the universe.

However, a little over a month ago, a pair of physicists said they found something potentially even more extraordinary in this radiation — giant rings they said could be evidence of a universe that existed before the Big Bang roughly 13.7 billion years ago.

The cosmic microwave background is normally slightly blotchy, showing variations in hot and cold that apparently originate from microscopic fluctuations in the very earliest moments after the Big Bang. Recently, a pair of researchers claimed to have found concentric ring patterns where this radiation is less patchy than normal.

So what are these circles within circles? 
They might be nothing less than the aftermath of collisions of supermassive black holes in a past universe, akin to ripples in a pond, according to calculations from mathematical physicist Roger Penrose at the University of Oxford in England and physicist Vahe Gurzadyan at Yerevan State University in Armenia that appeared online Nov. 16.

Sahara Desert from Space




The Sahara Desert extends eastward from the Atlantic Ocean some 3,000 miles to the Nile River and the Red Sea, and southward from the Atlas Mountains of Morocco and the Mediterranean shores more than 1,000 miles to the savannah called the Sahel. 

Credit: NASA's MODIS instrument (Moderate Resolution Imaging Spectroradiometer).

ESA Mars express HRSC Image: Phoenicis Lacus



Phoenicis Lacus has an area of 8100 sq km (59.5 x 136 km), which corresponds to the size of Corsica. 

This image was obtained on 31 July 2010 using the High-Resolution Stereo Camera (HRSC) on ESA's Mars Express spacecraft. 

Credit: ESA/DLR/FU Berlin (G. Neukum)

New images of Mars' Phoenix Lake region show where complex fault lines along a vast Martian plain have resulted in terrain with contrasting light and dark appearances. 

The Phoenix Lake region, formally called Phoenicis Lacus, was first spotted by 19th century astronomers, who identified it as a dark spot that resembled a sea. Scientists now know that it is not a body of water, but the southwestern extension of the maze-like Noctis Labyrinthus system of deep valleys.
 
Phoenicis Lacus has an area of 3,127 square miles (8,100 square kilometers), which is roughly equal to the size of the island of Corsica in the Mediterranean Sea. 

Only a small portion of the region is visible in the new images, which were obtained with the High-Resolution Stereo Camera on the European Space Agency's Mars Express spacecraft in orbit around the Red Planet.

Wednesday, December 22, 2010

NASA Cassini's Dramatic Views Of Rhea


Newly released for the holidays, images of Saturn's second largest moon Rhea obtained by NASA's Cassini spacecraft show dramatic views of fractures cutting through craters on the moon's surface, revealing a history of tectonic rumbling.

The images are among the highest-resolution views ever obtained of Rhea.

"These recent, high-resolution Cassini images help us put Saturn's moon in the context of the moons' geological family tree," said Paul Helfenstein, Cassini imaging team associate, based at Cornell University, Ithaca, N.Y.

"Since NASA's Voyager mission visited Saturn, scientists have thought of Rhea and Dione as close cousins, with some differences in size and density. The new images show us they're more like fraternal twins, where the resemblance is more than skin deep. This probably comes from their nearness to each other in orbit."

Cassini scientists designed the March 2010 and November 2009 encounters in part to search for a ring thought to encircle the moon. During the March flyby, Cassini made its closest- approach to Rhea's surface so far, swooping within 100 kilometers (62 miles) of the moon.

Based on these observations, however, scientists have since discounted the possibility that Rhea might currently have a faint ring above its equator.

These flybys nonetheless yielded unique views of other features on the moon, including ones that are among the best ever obtained of the side of Rhea that always faces away from Saturn.

Other views show a web of bright, "wispy" fractures resembling some that were first spotted on another part of Rhea by the two Voyager spacecraft in 1980 and 1981.

At that time, scientists thought the wispy markings on the trailing hemispheres - the sides of moons that face backward in the orbit around a planet - of Rhea and the neighboring moon Dione were possible cryovolcanic deposits, or the residue of icy material erupting. The low resolution of Voyager images prevented a closer inspection of these regions.

Solar Eclipse over NASA Space Shuttle Discovery

Credit Photo by NASA

The New Dust Ball

Dust Ball from Dave Hakkens on Vimeo.

Monday, December 20, 2010

At last a compound that prevents the growth of prostate cancer cells

Evidence pointing to the effects of monensin emerged in a project investigating the effects of nearly 5,000 drugs and micromolecules on the growth of prostate cancer cells. The project involved most of the drugs on the market today. Researchers found that small amounts of compounds — disulfiram (Antabus), thiram, tricostatin A, and monensin — can prevent the growth of prostate cancer cells without significant effects on the growth of the normal human prostate epithelial cells.

Further studies revealed that monensin caused prostate cancer cell death by reducing the amount of testosterone receptor and by increasing production of reactive oxygen species and inducing DNA damage. In addition, monensin was shown to have combined effects with anti-androgens — the drugs suppressing the effects of androgens — in preventing prostate cancer cell growth.

“These research findings give rise to a potential new use for the monensin. The results also demonstrate that the effects of anti-androgens in suppressing the growth of cancer cells can be enhanced by using drugs inducing production of reactive oxygen species”, say Senior Research Scientist Kristiina Iljin from VTT and Research Scientist Kirsi Ketola from the University of Turku.

The research findings concerning the effects of drugs and micromolecules were published in the Clinical Cancer Research journal in 2009. The effects of monensin on preventing the growth of prostate cancer was published in the Molecular Cancer Therapeutics journal in December 2010.

Recently, medical companies have shown great interest in these kinds of projects aiming at finding novel indications for established drugs. Since the dosage and adverse effects of drugs already in use and their combined effects with other drugs are relatively well known, this kind of drug repositioning may result in considerable cost savings.

Prostate cancer is the second most common cause of cancer death in men after lung cancer. It has been estimated that globally about 300,000 men die from prostate cancer every year.

Voyager Crosses Point Of Solar Stillness

The 33-year odyssey of NASA's Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind.

Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the Sun, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the Sun has slowed to zero. 


Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars.

The event is a major milestone in Voyager 1's passage through the heliosheath, the turbulent outer shell of the Sun's sphere of influence, and the spacecraft's upcoming departure from our solar system.

"The solar wind has turned the corner," said Ed Stone, Voyager project scientist based at the California Institute of Technology in Pasadena, Calif. "Voyager 1 is getting close to interstellar space."

Our sun gives off a stream of charged particles that form a bubble known as the heliosphere around our solar system. The solar wind travels at supersonic speed until it crosses a shockwave called the termination shock.

At this point, the solar wind dramatically slows down and heats up in the heliosheath.

Launched on Sept. 5, 1977, Voyager 1 crossed the termination shock in December 2004 into the heliosheath. Scientists have used data from Voyager 1's Low-Energy Charged Particle Instrument to deduce the solar wind's velocity.

When the speed of the charged particles hitting the outward face of Voyager 1 matched the spacecraft's speed, researchers knew that the net outward speed of the solar wind was zero.

This occurred in June, when Voyager 1 was about 17 billion kilometers (10.6 billion miles) from the Sun.
Because the velocities can fluctuate, scientists watched four more monthly readings before they were convinced the solar wind's outward speed actually had slowed to zero.

Analysis of the data shows the velocity of the solar wind has steadily slowed at a rate of about 20 kilometers per second each year (45,000 mph each year) since August 2007, when the solar wind was speeding outward at about 60 kilometers per second (130,000 mph). The outward speed has remained at zero since June.

The results were presented at the American Geophysical Union meeting in San Francisco.


Voyager Crosses Point Of Solar Stillness

NASA LRO: Unprecedented Topographic Map Of Moon

NASA's Lunar Reconnaissance Orbiter is allowing researchers to create the most precise and complete map to date of the moon's complex, heavily cratered landscape.

"This dataset is being used to make digital elevation and terrain maps that will be a fundamental reference for future scientific and human exploration missions to the moon," said Dr. Gregory Neumann of NASA's Goddard Space Flight Center in Greenbelt, Md.

"After about one year taking data, we already have nearly 3 billion data points from the Lunar Orbiter Laser Altimeter on board the LRO spacecraft, with near-uniform longitudinal coverage.

We expect to continue to make measurements at this rate through the next two years of the science phase of the mission and beyond.

Near the poles, we expect to provide near-GPS-like navigational capability as coverage is denser due to the spacecraft's polar orbit."

Neumann will present the map at the American Geophysical Union meeting in San Francisco December 17.
The Lunar Orbiter Laser Altimeter (LOLA) works by propagating a single laser pulse through a Diffractive
Optical Element that splits it into five beams.

These beams then strike and are backscattered from the lunar surface. From the return pulse, the LOLA electronics determines the time of flight which, accounting for the speed of light, provides a precise measurement of the range from the spacecraft to the lunar surface.



NASA's LRO Creating Unprecedented Topographic Map Of Moon

Soyuz Arrives at the International Space Station

Sunday, December 19, 2010

Hopes for new Alzheimer's and Parkinson's treatments

Diseases such as Alzheimer's and Parkinson's could be caused by just a handful of genetic "repeat offenders" in the brain, Scottish scientists have revealed.

Researchers have identified a small set of proteins responsible for more than 130 brain diseases, the biggest cause of disability in the world.

The scientists, led by Professor Seth Grant at the Wellcome Trust Sanger Institute and Edinburgh University, hope that the identification of such a relatively small number of damaging genetic triggers could lead to new treatments for brain disease.

Professor Grant said: "These diseases include common debilitating diseases such as Alzheimer's disease, Parkinson's disease and other neurodegenerative disorders as well as epilepsies and childhood developmental diseases including forms of autism and learning disability."

Neurology Professor Jeffrey L Noebels, of Baylor College of Medicine in Texas, said around half of the damaging proteins are "repeat offenders", giving researchers a strategic entry point to get to the bottom of brain diseases.

He added: "The rest of us have a front row seat to witness neuroscience unravel the complexity of human brain disorders."

The scientists say the findings open several new paths toward tackling these diseases.

"Since many different diseases involve the same set of proteins, we might be able to develop new treatments that could be used on many diseases", said Professor Grant.

"We also can see ways to develop new genetic diagnostic tests and ways to help doctors classify the brain diseases."

Friday, December 17, 2010

PTSD: Woman who cannot feel fear


A woman who cannot feel afraid because of a missing structure in her brain could help scientists discover treatments for post-traumatic stress disorder (PTSD).

Research published in Current Biology showed the woman felt no fear in a variety of scary situations.

These included exposure to snakes and spiders, horror films and a "haunted house". The woman feels other emotions but said as an adult, she had never felt afraid. She is the first known case of someone who is unable to process fear.

Researchers at the University of Iowa said her inability to feel frightened was because she is missing a structure in her brain called the amygdala.

The structure has long been associated with emotional learning - experiments in animals have shown that removing it makes them fearless. However, it has never been observed in a human before.

The woman experienced fear as a child and knows that some situations should be frightening. As an adult she has been in various frightening situations, including being threatened with a knife and held at gunpoint.

Researchers at the University of Iowa, in Iowa City, observed and recorded the woman's responses in situations that would make most people feel fear.

She watched a series of horror films, went to a reputedly haunted house and to an exotic pet store - where she handled dangerous snakes and asked to handle a tarantula.

She showed no fear in any of the situations and had to be prevented from touching the tarantula because of the high risk of being bitten.

When asked why she wanted to touch something that she knows is dangerous, she replied that she was overcome with curiosity.

Lead researcher Justin Feinstein said: "Because she is missing her amygdala, she is also missing the ability to detect and avoid danger in the world. "It is quite remarkable that she is still alive."

ESA Soyuz MagISStra: Paolo Nespoli arrives at the International Space Station

ESA astronaut Paolo Nespoli trying on his Russian Sokol suits at Star City, 15 November 2010.

He will travel to the International Space Station (ISS) on a long-duration mission in December, serving as flight engineer for Expeditions 26 and 27.

This will be the third six-month mission by a European astronaut on the Station.

From December 2010 to May 2011, Paolo Nespoli, ESA's Italian astronaut, will carry out an intensive programme of experiments, ranging from radiation monitoring to measurements that could improve oil recovery in petroleum reservoirs.

His duties aboard the ISS include participating in the docking operations to receive two cargo spacecraft: Europe’s second Automated Transfer Vehicle (ATV) Johannes Kepler, and the second Japanese HII Transfer Vehicle (HTV).

Both are unmanned spacecraft used to resupply the ISS. Nespoli will be the prime operator for berthing the HTV to the Station after the free-flying vehicle has been captured by his crewmate Catherine Coleman.

Credits: ESA - S. Corvaja, 2010

MagISStra Soyuz craft docking at ISS

Soyuz docking monitor and control view.

The Soyuz TMA-20 spacecraft docked this evening with the International Space Station carrying ESA astronaut Paolo Nespoli and his crewmates Dmitri Kondratyev and Catherine Coleman. They will stay in orbit now for six months and return to Earth next May.

ESA’s third long-duration mission aboard the International Space Station (ISS) began last Wednesday, 15 December, when the Soyuz spacecraft was launched from Baikonur Cosmodrome in Kazakhstan.

After circling the globe some 35 times in the last two days, the spacecraft docked at 21:12 CET (20:12 GMT) this evening.

During this third flight day, the crew prepared their vessel for arrival, closed the hatch between its two modules, donned their Sokol pressure suits and carefully monitored the approach and docking sequence.

Harrier Jump Jets Farewell

Different models of Royal Air Force Harrier jets take part in what was billed as their final flight, at RAF Cottesmore, before they were  prematurely axed by UK Government spending cuts.

Picture: PA

Replicate Tron Light Cycle

A designer has created ten street-legal replicas of the Tron Light Cycle.

The bikes are available to rent from Parker Brothers Choppers, based in Florida, USA.
 
See a video of the bike in action here:

NASA Mars Rover Opportunity: Alligator tail rock

A rock that looks like an alligator's tail is seen on the surface of Mars in this Navcam panorama image from the red planet.

The picture showing many interestingly shaped rocks and the edge of the Santa Maria crater was taken by the Mars rover Opportunity on December 15.

Picture: NASA / BARCROFT MEDIA

Rocket-triggered lightning in Florida

This University of Florida image shows rocket-triggered lightning at the UF/FIT International Centre for Lightning research and Testing near Gainsville, Florida.

Researchers for the first time have captured X-ray images of lightning, a feat that they hope will help them better predict how lightning moves.

A team from the Florida Institute of Technology and University of Florida launched small rockets into thunderclouds.

Using a special camera, the researchers recorded X-rays coming from the resulting light flashes before they hit the ground. Scientists have known that lightning emits X-rays, but they don't fully understand it.

Picture: AP / UNIVERSITY OF FLORIDA

Thursday, December 16, 2010

First measurement of magnetic field in Earth’s core

A University of California, Berkeley, geophysicist has made the first-ever measurement of the strength of the magnetic field inside Earth’s core, 1,800 miles underground.

The magnetic field strength is 25 Gauss, or 50 times stronger than the magnetic field at the surface that makes compass needles align north-south. Though this number is in the middle of the range geophysicists predict, it puts constraints on the identity of the heat sources in the core that keep the internal dynamo running to maintain this magnetic field.

“This is the first really good number we’ve had based on observations, not inference,” said author Bruce A. Buffett, professor of earth and planetary science at UC Berkeley. “The result is not controversial, but it does rule out a very weak magnetic field and argues against a very strong field.”

The results are published in the Dec. 16 issue of the journal Nature.

A strong magnetic field inside the outer core means there is a lot of convection and thus a lot of heat being produced, which scientists would need to account for, Buffett said. The presumed sources of energy are the residual heat from 4 billion years ago when the planet was hot and molten, release of gravitational energy as heavy elements sink to the bottom of the liquid core, and radioactive decay of long-lived elements such as potassium, uranium and thorium.

A weak field — 5 Gauss, for example — would imply that little heat is being supplied by radioactive decay, while a strong field, on the order of 100 Gauss, would imply a large contribution from radioactive decay.

“A measurement of the magnetic field tells us what the energy requirements are and what the sources of heat are,” Buffett said.

About 60 percent of the power generated inside the earth likely comes from the exclusion of light elements from the solid inner core as it freezes and grows, he said. This constantly builds up crud in the outer core.

The Earth’s magnetic field is produced in the outer two-thirds of the planet’s iron/nickel core. This outer core, about 1,400 miles thick, is liquid, while the inner core is a frozen iron and nickel wrecking ball with a radius of about 800 miles — roughly the size of the moon. The core is surrounded by a hot, gooey mantle and a rigid surface crust.

Wednesday, December 15, 2010

NASA Shuttle Discovery STS-133 Launch: No earlier than Feb 3rd 2011

 STS133-S-002 -- STS-133 crew  


Technicians at NASA Kennedy Space Center’s Launch Pad 39A in Florida are moving ahead with plans for a tanking test for space shuttle Discovery’s external fuel tank, which now will be no earlier than Friday, Dec. 17, weather permitting.

Cold and windy conditions have slowed test preparation. The test will help verify repairs associated with cracks on the tops of two 21-foot-long, U-shaped aluminum brackets, called stringers, and help engineers determine what caused the cracks in the first place during Discovery’s launch countdown on Nov. 5.

Shuttle managers also decided late Monday afternoon that following the tanking test they plan to roll Discovery back into Kennedy’s Vehicle Assembly Building (VAB) to allow its external tank to undergo additional image scans.

Rollback is expected to occur four to five days after the tanking test. Once in the VAB, technicians would collect X-ray data on stringers on the back side of the external tank midsection, called the intertank, which is not accessible at the launch pad.

Additionally, the test instrumentation and foam insulation on those areas of the intertank would be removed and the area would be prepared again for launch. In parallel, the back side stringer inspections would take place.

At the launch pad, crews currently are replacing foam insulation after installing 89 strain gauges and temperature sensors for the tanking test to precisely record movement and temperatures from the intertank as it chills and warms again during the loading of propellants and emptying process. The tank holds super-cold liquid oxygen and liquid hydrogen, which cause the tank to shrink by about half an inch.

Managers and engineers will review the data gathered from the tanking test and additional image scans before determining the next course of action. Currently, managers plan to have Discovery returned to the launch pad in January ahead of its next launch opportunity, which is no earlier than Feb. 3 at 1:34 a.m. EST.

NASA Mars Odyssey: Udzha Crater

Although it is 45 kilometers (28 miles) wide, countless layers of ice and dust have all but buried Udzha Crater.

Udzha lies near the edge of the northern polar cap, and only the topmost edges of its crater rim rise above the polar deposits to hint at its circular shape.

The image was taken by the Thermal Emission Imaging System instrument on NASA's Mars Odyssey orbiter and posted in a special December 2010 set marking the occasion of Odyssey becoming the longest-working Mars spacecraft in history. The pictured location on Mars is 81.8 degrees north latitude, 77.2 degrees east longitude.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Science Mission Directorate, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing.

The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Image credit: NASA/JPL-Caltech/ASU

More Mars Odyssey Images here

NASA IBEX: first images of magnetotail structures

Image courtesy of NASA/IBEX Science Team

This image shows the first-ever view of the magnetospheric plasma sheet in profile, as seen by the Interstellar Boundary Explorer (IBEX) from outside the magnetosphere.

It shows the densest portions of the plasma sheet, largely following the modeled magnetic structure.

Invisible to the naked eye, yet massive in structure around the Earth is the magnetosphere, the region of space around the planet that ebbs and flows in response to the million-mile-per-hour flow of charged particles continually blasting from the Sun.

NASA's Interstellar Boundary Explorer (IBEX) spacecraft, designed to image the invisible interactions occurring at the edge of the solar system, captured images of magnetospheric structures and a dynamic event occurring in the magnetosphere as the spacecraft observed from near lunar distance.

Tuesday, December 14, 2010

NASA Hubble Image: Supernova Bubble

A delicate sphere of gas, photographed by NASA's Hubble Space Telescope, floats serenely in the depths of space.

The pristine shell, or bubble, is the result of gas that is being shocked by the expanding blast wave from a supernova.

Called SNR 0509-67.5 (or SNR 0509 for short), the bubble is the visible remnant of a powerful stellar explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light-years from Earth.

Ripples in the shell's surface may be caused by either subtle variations in the density of the ambient interstellar gas, or possibly driven from the interior by pieces of the ejecta.

The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 11 million miles per hour (5,000 kilometers per second).

Astronomers have concluded that the explosion was one of an especially energetic and bright variety of supernovae. Known as Type Ia, such supernova events are thought to result from a white dwarf star in a binary system that robs its partner of material, takes on much more mass than it is able to handle, and eventually explodes.

Hubble's Advanced Camera for Surveys observed the supernova remnant on Oct. 28, 2006 with a filter that isolates light from glowing hydrogen seen in the expanding shell.

These observations were then combined with visible-light images of the surrounding star field that were imaged with Hubble's Wide Field Camera 3 on Nov. 4, 2010.

With an age of about 400 years as seen from Earth, the supernova might have been visible to southern hemisphere observers around the year 1600, however, there are no known records of a "new star" in the direction of the LMC near that time.

A more recent supernova in the LMC, SN 1987A, did catch the eye of Earth viewers and continues to be studied with ground- and space-based telescopes, including Hubble.

Mechanism Boasts Memory: Neuropeptide S

In collaboration with scientists at Germany's University of Munster, the UC Irvine team found that a small protein called neuropeptide S can strengthen and prolong memories of everything from negative events to simple objects.

According to study leader Rainer Reinscheid, UCI associate professor of pharmaceutical sciences, the discovery could provide important clues about how the brain stores memories and also lead to new treatments for Alzheimer's disease, dementia and other cognitive impairments.

"Additionally, it may help us better understand post-traumatic stress disorder, which involves exaggerated memories of traumatic events," he said.

In tests on mice, the researchers observed that if neuropeptide S receptors in the brain were activated immediately after a learning experience, it could be recalled for much longer and with much greater intensity.

This memory enhancement lasted up to a week, Reinscheid said, but when NPS receptor activation was disrupted, the mice didn't remember events as strongly -- if at all -- when tested just a day or two later.

Study results, which appear in the journal Neuro-psycho-pharmacology, are in accordance with Reinscheid's previous findings that NPS causes wakefulness and has a calming effect.

"It appears that the combination of increased alertness and reduced anxiety produced by NPS prepares the animals to learn much better," he said. "Memory is remarkably improved after activation of their NPS system, and the effects are long-lasting, independent of content."

Naoe Okamura, Celia Garau, Dee Duangdao and Stewart Clark of UCI as well as Kay Jungling and Hans-Christian Pape of the University of Munster contributed to the study, which was funded in part by the National Institute of Mental Health.

NASA JPL: Giant ice volcano found on Titan

A potential new ice volcano has been found on Saturn's moon Titan.

Named Sotra, the volcano is nearly 1 kilometre tall and has a 1.6-kilometre-deep pit alongside it.

Surrounded by giant sand dunes, it is thought to be the largest in a string of several volcanoes that once spewed molten ice from deep beneath the moon's surface.

"We think we have found the strongest case yet for an ice volcano on Titan," said Randy Kirk, a geophysicist at the US Geological Survey in Flagstaff, Arizona. "What we see is not just a flow like we see in other places, it's like a volcanic field would be on Earth."

Titan is about the size of the planet Mercury but has an atmosphere thicker than Earth's. This makes it incredibly difficult for astronomers to know what's happening on the surface. Planetary scientists, including Kirk, are using NASA's Cassini spacecraft to map the moon, but so far only about half of Titan has been imaged.

Kirk and his team created a 3D mapping technique that patches together multiple images of the same area, so they were lucky that Sotra was in one of the rare places imaged twice.

"The classical volcano everybody thinks of when you say the word is a mountain with a crater on it and lava flows coming out of it," said Kirk. "That's what we've found on Titan."
'This is it'

The team cannot be certain if the chain is active, but described the find as the best evidence found so far for a cryovolcano, or ice volcano. Previously, bright spots seen in low-resolution satellite images have been interpreted as volcanic flows and craters. However, once those areas were mapped in 3D, it became obvious they weren't volcanoes.

"We had noted Sotra Facula as a candidate cryovolcano before," said Rosaly Lopes at NASA's Jet Propulsion Laboratory in Pasadena, California. "But it was only when Randy got the topography done that we realised, wow, this is it."

Earth's interior is divided into distinct layers of rock and liquid magma. When this molten rock erupts through the planet's crust, it's known as volcanism. Titan's volcanism is more complicated because beneath the moon's surface lies a layer of ice. Even a small amount of internal heat could create molten ices. Because the liquid would be less dense, it would force its way to the surface. The result would be a massive eruption of slushy liquid and gases similar to what scientists have seen on other icy moons.

"Ice at outer solar system temperatures is very rigid," Kirk said. "Ice at close to its melting point is soft. What would be a glacier on Earth would be a volcano on a body that's made of that same material. It's the difference between the cake and the frosting."



Giant ice volcano may have been found on Titan - space - 14 December 2010 - New Scientist

NASA ISS Image: Houston - Space City


Photo Courtesy of NASA Astronaut Clayton Anderson

NASA ISS Image: HPS9 Glacier in Chilean Patagonia

Photo Courtesy of NASA Astronaut Clayton Anderson

Qatar funds collaborative discovery of new exo-Planet

PhD students Grant Miller and David Brown used Scotland's largest optical telescope, the 0.9m diameter James Gregory telescope at the St Andrews campus observatory, to confirm the presence and measure the diameter of the new planet, contributing to the discovery of a new alien world.

The St Andrews team helped to find the new planet in record time thanks to teamwork and internet communications between astronomers in Qatar, the US, Germany, Denmark, and at the Universities of Leicester and Keele.

The group said this discovery was a good example of successful collaboration across international borders and time zones.

The planet, described as a 'hot Jupiter' which has been named Qatar-1b, adds to the growing list of alien planets orbiting distant stars discovered by scientists around the world.

These distant planets are detected by scientists who closely study the light emitted by stars. Because the planets orbit their parent star, and will regularly pass directly between it and the earth and block its light, causing a characteristic dip in the amount of light coming from the star.

While a huge number of stars are observed, only a few will have detectable planets.

In this case, Qatar's wide-angle cameras - located in New Mexico - took images of the sky every clear night beginning in early 2010. The digital images then were transmitted to the UK for computer analysis by collaborating astronomers at St Andrews, Leicester and Qatar.

Data from hundreds of thousands of stars was examined after it was extracted from the images, and the analysis narrowed the field to a few hundred possible stars.

The group followed up on the most promising candidates with Dr David Latham from the Harvard-Smithsonian Centre for Astrophysics, making observations from Arizona to weed out binary-star systems with grazing eclipses that can mimic planetary transits. The resulting data measured the mass of the new planet.

Dr Latham said: "The discovery of Qatar-1b is a wonderful example of how science and modern communications can erase international borders and time zones. No one owns the stars. We can all be inspired by the discovery of distant worlds."

Qatar-1b is a gas giant planet, 20% larger than Jupiter in diameter and 10% more massive. It belongs to the 'hot Jupiter' family because it orbits 3.5 million km from its star, so close that it roasts at a temperature of around 1100 degrees Celsius. The orbital period is just 34 hours.

St Andrews astronomer Professor Keith Horne said: "Qatar-1b is just the beginning. With Qatar's new planet-hunting cameras, we should soon be finding smaller planets as well, hot Saturns and hot Neptunes, and ultimately, with a different technique, cool Earths.

Mount Merapi volcanic ash for sale

A bottle containing volcanic ash from Mount Merapi is seen in Yogyakarta, Indonesia. The ash from the country's most volatile volcano is being sold for $1 per bottle to raise money for victims of its eruption. The writing on the sticker says 'Year 2010, DANGER, Composition: Merapi volcanic ash. Containing SiO2/silica, may cause severe damage to lungs, eyes and infection to respiratory system.'
A bottle containing volcanic ash from Mount Merapi is seen in Yogyakarta, Indonesia.

The ash from the country's most volatile volcano is being sold for $1 per bottle to raise money for victims of its eruption.

The writing on the sticker says "Year 2010, DANGER, Composition: Merapi volcanic ash. Containing SiO2/silica, may cause severe damage to lungs, eyes and infection to respiratory system."
 
Picture: AP

Russian Soyuz TMA-20 spacecraft blessed

A Russian Orthodox priest blesses the Soyuz TMA-20 spacecraft on the launch pad at the Russian leased Baikonur cosmodrome in Kazakhstan. The rocket is set to blast off to the International Space Station on December 15, with US astronaut Cady Coleman, Italian astronaut Paolo Nespoli and Russian cosmonaut Dmitry Kondratiev on board
A Russian Orthodox priest blesses the Soyuz TMA-20 spacecraft on the launch pad at the Russian leased Baikonur cosmodrome in Kazakhstan.

The rocket is set to blast off to the International Space Station on December 15, with US astronaut Cady Coleman, Italian astronaut Paolo Nespoli and Russian cosmonaut Dmitry Kondratiev on board.

Picture: GETTY

Carl Sagan's Voyager near Solar System's edge

Voyager 1, one of the first satellites launched by Carl Sagan and his visionary team, is now the most distant spacecraft from Earth.

Voyager 1 has reached a new milestone in its quest to explore the edge of the Solar System.

Now 17.4bn km (10.8bn miles) from home, the veteran probe has detected a distinct change in the flow of particles that surround it.

These particles, which emanate from the Sun, are no longer travelling outwards but are moving sideways.

It means Voyager must be very close to making the jump to interstellar space - the space between the stars.

Edward Stone, the most recent Voyager project scientist, lauded the explorer and the fascinating science it continues to return 33 years after launch.

"When Voyager was launched, the space age itself was only 20 years old, so there was no basis to know that spacecraft could last so long," he said.

"We had no idea how far we would have to travel to get outside the Solar System. We now know that in roughly five years, we should be outside for the first time."

Dr Stone was speaking here at the American Geophysical Union (AGU) Fall Meeting, the largest gathering of Earth scientists in the world.

Particle bubble

Voyager 1 was launched by NASA and Carl Sagan, on 5 September 1977, and its sister spacecraft, Voyager 2, on 20 August 1977.

The Nasa probes' initial goal was to survey the outer planets Jupiter, Saturn, Uranus and Neptune, a task completed in 1989. The was the first ever fly-by of the planets.

They were then despatched towards deep space, in the general direction of the centre of our Milky Way Galaxy. But before doing that the spacecraft was turned towars the Earth, which at that time was a mear dot in the Universe. The picture taken and downloaded, is known as the iconic 'Earth, the pale blue dot.'

Radioactive Power
Sustained by their radioactive power packs, the probes' instruments continue to function well and return data to Earth, although the vast distance between them and Earth, plus the low tech comms equipment, means a radio message now has a travel time of about 16 hours.

The newly reported observation comes from Voyager 1's Low-Energy Charged Particle Instrument, which has been monitoring the velocity of the solar wind.

This stream of charged particles forms a bubble around our Solar System known as the heliosphere, as shown in the picture. The wind travels at "supersonic" speed until it crosses a shockwave called the 'termination shock.'

At this point, the wind then slows dramatically and heats up in a region termed the heliosheath. Voyager has determined the velocity of the wind at its location has now slowed to zero.

Voyaging onwards

"We have gotten to the point where the wind from the Sun, which until now has always had an outward motion, is no longer moving outward; it is only moving sideways so that it can end up going down the tail of the heliosphere, which is a comet-shaped-like object," said Dr Stone, who is based at the California Institute of Technology in Pasadena, California.

This phenomenon is a consequence of the wind pushing up against the matter coming from other stars. The boundary between the two is the "official" edge of the Solar System - the heliopause. Once Voyager crosses over, it will be in interstellar space.

First hints that Voyager had encountered something new came in June. Several months of further data were required to confirm the observation.

"When I realised that we were getting solid zeroes, I was amazed," said Rob Decker, a Voyager Low-Energy Charged Particle Instrument co-investigator from the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

"Here was Voyager, a spacecraft that has been a workhorse for 33 years, showing us something completely new again."

Voyager is racing on towards the heliopause at 17km/s. Dr Stone expects the cross-over to occur within the next few years.

Monday, December 13, 2010

NASA Wise Image: Jellyfish Nebula - Explosion in Infra-red light



Image credit: NASA/JPL-Caltech/UCLA

In this WISE image, infrared light has been colour-coded to reveal what our eyes cannot see.

The colours differ primarily because materials surrounding the supernova remnant vary in density. When the shock waves hit these materials, different gases were triggered to release a mix of infrared wavelengths.

The supernova remnant's northeastern shell, seen here as the violet-coloured semi-circle at top left, is composed of sheet-like filaments that are emitting light from iron, neon, silicon and oxygen gas atoms and dust particles heated by a fast shock wave traveling at about 100 kilometers per second, or 223,700 mph.

The smaller southern shell, seen in bright bluish colours, is constructed of clumps and knots primarily emitting light from hydrogen gas and dust heated by a slower shock wave traveling at about 30 kilometers per second, or 67,100 miles per hour.

This oddly colourful nebula is the supernova remnant IC 443 as seen by NASA's Wide-field Infrared Survey Explorer, or WISE. Also known as the Jellyfish nebula, IC 443 is particularly interesting because it provides a look into how stellar explosions interact with their environment.

IC 443 can be found near the star Eta Geminorum, which lies near Castor, one of the twins in the constellation Gemini.

Just like human beings, stars have a life cycle - they are born, mature and eventually die. The manner in which stars die depends on their mass. Stars with mass similar to the sun typically become planetary nebulae at the end of their lives, whereas stars with many times the sun's mass explode as supernovae.

IC 443 is the remains of a star that went supernova somewhere between 5,000 and 10,000 years ago. The blast from the supernova sent out shock waves that traveled through space, sweeping up and heating the surrounding gas and dust in the interstellar medium, and creating the supernova remnant seen in this image.

SANSA - South African National Space Agency launched

South Africa launched its space agency last Thursday on what has been described as a historic day for the country. Science and Technology Minister Naledi Pandor and experts from the space agencies of other countries Thursday attended the launch of the South African Space Agency (SANSA).


South Africa now joins a select group of countries that boast having a space agency, the state-run BuaNews agency reported. Outlining SANSA's role, the minister said it will implement a national space programme and advise her on the subject.

It will have the responsibility of acquiring, assimilating and distributing space data to various state entities.

Pandor said the national space strategy will promote research in the areas of astronomy, earth observation, communications, navigation and space physics. The strategy will foster international cooperation in space-related activities, and advance scientific, engineering and technological competencies through outreach programmes.

Emphasis would be placed on encouraging space science research and development, she added.

She said the space industry is a big business and went beyond just space travel. It is an industry with enormous potential future growth. Over the next five years, South Africa intends to develop a formal space programme.

'Our combined efforts at enhancing South Africa's space capabilities will not only be of immense value to the scientific community in the southern African region. It will also assist in addressing the persistent challenges of health care provision, water resources, agricultural mapping, and urban planning and communications,' she said.

She announced further plans aimed at strengthening the space sector, which included setting up a Centre of Competence in Optronics and Synthetic Aperture Radar.

Space science has contributed significantly in the sustainable development of the African continent and SANSA will help play a role in this regard, the minister added.

Chair of the SANSA board, Maurice Magugumela, said SANSA has ushered in a new era in the science and technology landscape in South Africa and the continent.

Pandor signed a memorandum of understanding (MoU) relating to data access with the representatives of the Brazilian and Chinese governments.

NASA Saturn: Large Satellite may have led to the formation of Saturn’s rings

Simulations performed at Southwest Research Institute may explain how Saturn’s majestic rings and icy inner moons formed following the collision of a Titan-sized satellite with the planet, according to a paper published in Nature magazine’s Dec. 12 Advance Online Publication.

Saturn’s rings are at present 90 to 95 percent water ice. Because dust and debris from rocky meteoroids have polluted the rings, the rings are believed to have consisted of pure ice when they formed.

This composition is unusual compared to the approximately half-ice and half-rock mixture expected for materials in the outer Solar System. Similarly, the low densities of Saturn’s inner moons show that they too are, as a group, unusually rich in ice.

The previous leading ring origin theory suggests the rings formed when a small satellite was disrupted by an impacting comet. “This scenario would have likely resulted in rings that were a mixture of rock and ice, rather than the ice-rich rings we see today,” says the paper’s author, Dr. Robin M. Canup, associate vice president of the SwRI Planetary Science Directorate in Boulder.

The new theory links the formation of the rings to the formation of Saturn’s satellites. While Jupiter has four large satellites, Saturn has only one, Titan. Previous work suggests that multiple Titan-sized satellites originally formed at Saturn, but that those orbiting interior to Titan were lost as their orbits spiraled into the planet.

As the final lost satellite neared Saturn, heating caused by the flexing of its shape by the planet’s gravity would cause its ice to melt and its rock to sink to its center. Canup uses numerical simulations to show that as such a satellite crosses the region of the current B ring, planetary tidal forces strip material from its outer icy layers, while its rocky core remains intact and eventually collides with the planet. This produces an initial ice ring that is much more massive than Saturn’s current rings.

Over time, collisions in the ring cause it to spread radially and decrease in mass. Inwardly spreading ring material is lost, while material spreading past the ring’s outer edge accumulates into icy moons with estimated masses consistent with the inner moons seen today.

“The new model proposes that the rings are primordial, formed from the same events that left Titan as Saturn’s sole large satellite, ” says Canup. “The implication is that the rings and the Saturnian moons interior to and including Tethys share a coupled origin, and are the last remnants of a lost companion satellite to Titan.”

During its extended mission, the Cassini spacecraft will measure the rings’ current mass and will indirectly measure the pollution rate of the rings. This should provide an improved estimate of the rings’ age and a test of the new ring origin model.

NASA’s Outer Planets Research Program funded this research. The paper, “Origin of Saturn’s Rings and Inner Moons by Mass Removal from a Lost Titan-Sized Satellite,” by Dr. R.M. Canup, was published in Nature magazine’s Dec. 12 Advance Online Publication.

Friday, December 10, 2010

Amelia Earhart's Finger Bone Recovered

A tiny bone fragment could provide crucial information about the fate of Amelia Earhart, the legendary pilot who disappeared 73 years ago while flying over the Pacific Ocean in a record attempt to fly around the world at the equator.

Collected on Nikumaroro, an uninhabited tropical island in the southwestern Pacific republic of Kiribati, the bone has raised the interest of The International Group for Historic Aircraft Recovery (TIGHAR), which has long been investigating the Earhart mystery, as it may be from a human finger.

The phalax was found together with other artifacts during a month-long expedition last June to the tiny coral atoll believed to be Earhart's final resting place.

"At first we assumed it was from the turtle whose remains we found nearby. Indeed, sea turtles have finger bones in their flippers. But further research suggests it could also be human," Ric Gillespie, executive director of TIGHAR, told Discovery News.

Read more here Amelia Earhart's Finger Bone Recovered? : Discovery News

The Sno-Ped a Snow Bike for Bad Weather

Designer Michele Marin has dreamed up a human-powered snow machine that will get you over the powdery hills without the need for a fossil fueled engine -- and alternative for those of us who want to enjoy zipping over hills with more finesse than a snowmobile can offer, if not the same amount of speed.

Whipping along icy streets on a bike isn’t everyone’s cup of tea, so for those who miss the exhilaration of an outdoor commute during the winter months, this human-powered snow vehicle could be right up your alley.



Outside of the obvious green advantage of not using fossil fuels, the construction of the vehicle itself also gets a high grade on the eco-friendly scale with a frame made of recyclable, bent-aluminum sheets.

It may never replace skis as the preferred mode of winter travel, but a cup holder and solar-powered bumwarmer could change that in a snap

ESA MARS Express Image: Rim of Schiaparelli impact basin

The small crater embedded in the northwestern rim of the Schiaparelli impact basin features prominently in this new image from ESA’s Mars Express.

All around is evidence for past water and the great martian winds that periodically blow.

Schiaparelli is a large impact basin about 460 km in diameter located in the eastern Terra Meridiani region of the equator of Mars.

The centre of the basin lies at about 3°S/17°E and is named after the Italian astronomer Giovanni Schiaparelli (1835–1910). Although he also studied Mercury and Venus, he is best known for his observations of the Red Planet.
During the ‘Great Opposition’ of 1877, when Mars passed close to Earth, Schiaparelli mapped the planet, perceiving a number of straight dark lines across the red surface.

He assumed that these were natural water-filled channels and used the equivalent Italian word, ‘canali’.

However, other astronomers thought he meant canals, meaning artificial irrigation and transportation routes, which led to a few astronomers, and a large number of the general public, believing that they had been created by intelligent Martians.

Now we know that Schiaparelli’s ‘canali’ were illusions created by the comparatively poor telescopes of the time and there are no water-filled channels on Mars today. Nevertheless, there is evidence in this new picture that water was once present in this region of the planet, perhaps in the form of a lake.

NASA HST Image: Pismis 24 in NGC 6357 Nebula, part of Scorpius

The small open star cluster Pismis 24 lies in the core of the NGC 6357 nebula in Scorpius, about 8,000 light-years away from Earth.

The brightest object in the center of this image is designated Pismis 24-1 and was once thought to weigh as much as 200 to 300 solar masses.

This would not only have made it by far the most massive known star in the galaxy, but would have put it considerably above the currently believed upper mass limit of about 150 solar masses for individual stars.

However, Hubble Space Telescope high-resolution images of the star show that it is really two stars orbiting one another that are each estimated to be 100 solar masses.

In addition, spectroscopic observations with ground-based telescopes further reveal that one of the stars is actually a tight binary that is too compact to be resolved even by Hubble.

This divides the estimated mass for Pismis 24-1 among the three stars. Although the stars are still among the heaviest known, the mass limit has not been broken due to the multiplicity of the system.

The images of NGC 6357 were taken with Hubble's Wide Field and Planetary Camera 2 in April 2002.

ImageCredit: NASA, ESA, and J. Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain)

Artificial Kidney Implant good news for patients



About 85,000 people need kidney transplants each year, but fewer than 20,000 kidneys are available. To survive, people with chronic kidney disease must undergo dialysis for 4 hours at a time, multiple times each week.

UCSF Professor of Bioengineering, Shuvo Roy, PhD, is leading a team of researchers to develop an implantable artificial kidney that could make dialysis a thing of the past.

ESA ENVISAT Observing the Earth: Great Barrier Reef

This Envisat image features part of the Great Barrier Reef off Australia’s Queensland coast.

It is the world’s most protected marine area, one of its natural wonders and a World Heritage site.

Coral reefs consist of huge numbers of individual coral polyps – soft-bodied, invertebrate animals – linked by tissue.

The Great Barrier Reef is an interlinked system of about 3000 reefs and 900 coral islands, divided by narrow passages, just beneath the surface of the Coral Sea.

Spanning more than 2000 km and covering an area of some 350 000 sq km, it is the largest living structure on Earth and the only one visible from space. The southern part of the reef is pictured here.

Creating conditions for coral polyps to colonise here took some time. The reef we see today originated during the last Ice Age when water from the melting ice inundated the edge of the continental shelf. It is believed to be built upon a platform from an earlier reef structure dating back some 18 000 years.

As diverse as a rainforest with numerous types of habitats, the reef hosts thousands of marine animals, including sharks, barracuda, turtles and some 1500 tropical fish species.

Fraser Island juts out into the sea (bottom right). Green and tan swirls around the coast are due to sediments being transported in the water.

This image was acquired by Envisat’s Medium Resolution Imaging Spectrometer on 8 November at a resolution of 300 m.

Thursday, December 9, 2010

Fewer Synapses, More Efficient Learning: Molecular Glue Wires the Brain

Yale University researchers have found that a single molecule not only connects brain cells but also changes how we learn. The findings, reported in the December 9 issue of the journal Neuron, may help researchers discover ways to improve memory and could lead to new therapies to correct neurological disorders.


The junctions between brain cells over which nerve pulses pass -- called synapses -- are crucial for regulating learning and memory and how we think. Aberrations in the structure and function of synapses have been linked to mental retardation and autism, while synapses are lost in the aging brains of Alzheimer's patients.

However, the mechanisms that organize synapses in the living brain remain a puzzle. Yale scientists identified one critical piece of this puzzle, a molecule called SynCAM 1 that spans across synaptic junctions.

"We hypothesized that this molecule might promote new synapses in the developing brain, but were surprised that it also impacts the maintenance and function of these structures," said Thomas Biederer, associate professor of molecular biophysics and biochemistry and senior author of the study. "We can now define how this molecule supports the brain's ability to wire itself."

The Yale team focused on SynCAM 1, an adhesion molecule that helps to hold synaptic junctions together. They found that when the SynCAM 1 gene was activated in mice, more synaptic connections formed. Mice without the molecule produced fewer synapses.

When we learn, new synapses can form. However, the strength of synaptic connections also changes during learning, based on the amount of stimuli received -- a quality scientists termed "plasticity." Together with a group in Germany led by Valentin Stein, the team was surprised to find that SynCAM 1 controls an important form of synaptic plasticity.

Unexpectedly, Biederer and colleagues also found that mice with high amounts of SynCAM 1 are unable to learn while mice lacking SynCAM 1 -- and having fewer synapses -- learn better. Apparently an excess of the molecule can be damaging. This builds on recent theories suggesting that having too many connections isn't always better and that the balance of synaptic activity is crucial for proper learning and memory.

"Synapses are dynamic structures. It appears that SynCAM 1 ties synapses together; some of this molecule is needed to promote contact but too much glues down the synapse and inhibits its function. It may act a bit like a sculptor who helps give synapses their shape." Biederer also said that the molecule is almost identical in mice and man, and likely has the same roles in human brains.

Journal Reference:
  1. Elissa M. Robbins, Alexander J. Krupp, Karen Perez De Arce, Ananda K. Ghosh, Adam I. Fogel, Antony Boucard, Thomas C. Südhof, Valentin Stein, Thomas Biederer. SynCAM 1 adhesion dynamically regulates synapse number and impacts plasticity and learning. Neuron, 2010; 68 (5): 894-906 DOI: 10.1016/j.neuron.2010.11.003