Sunday, January 31, 2010
Four-legged tracks in mud cause paleontologists re-think
A beach "provides a ready food source of stranded marine animals," the study's authors say. That would have allowed marine
ancestors of four-legged creatures to evolve "terrestrial competence" while dining on "a new and essentially untouched resource."
The trackway discovery "is undoubtedly one of the most extraordinary and unexpected finds in paleontology for decades, perhaps a century," says paleontologist John Long of the Natural History Museum of Los Angeles County.
Until the discovery, paleontologists thought the evolutionary transition from fishes to land animals was tightly nailed down to fossils dated about 379 million years old, he says.
The tracks "lob a grenade" into fossil studies of the earliest land creatures, Philippe Janvier and Gael Clement of the Muséum National d'Histoire Naturelle in Paris say in a commentary accompanying the study.
Not so fast, Tiktaalik's discoverers say. "Trace fossils such as these presumed vertebrate tracks and trackways, however, are a notoriously difficult class of evidence to interpret with full confidence," says Ted Daeschler of the Academy of Natural Sciences in Philadelphia by e-mail. "With all respect to the scientists involved in this study, there may be other explanations for these suggestive tracks."
The study authors acknowledge they have only fossil tracks, not bones, from their four-legged creature, which perhaps resembled an oversized salamander. Based on its gait, the critter floated in the tide while making tracks. The authors recommend from their finding that other paleontologists look for fossils of four-legged creatures as far back as 420 million years ago.
Scottish scientists who reach for stars ‘are leading the world’
The photograph was taken by the Vista telescope at the European Southern Observatory, using technology designed and built at the UK Astronomy Technology Centre in Edinburgh. That contribution was symbolic of the global importance of the country’s research base, said Anne Glover, the Scottish government’s chief scientific adviser.
“In every area of science Scotland outperforms the world average; our performance is truly stunning for a nation of only five million people,” Professor Glover said. “This is a country full of potential for those in science, engineering and technology.”
Professor Glover was speaking at the presentation of a report that purports to demonstrate the continuing success of home-grown scientists and engineers by comparing rates of publication of academic studies, and by collating the numbers of citations achieved by Scottish researchers in articles published by their peers from other countries.
The 120-page document showed that in sciences as diverse as medicine, agriculture and biology, Scotland has achieved 1.8 per cent of the world’s academic citations, from a population share of less than 0.1 per cent. Scotland even led the field in space sciences, Professor Glover said, though more dogs than Scots have experienced space travel so far.
To read the full article, click here .....
Saturday, January 30, 2010
Natural World: The Chimpcam Project
How does a chimpanzee see the world? A research project at Edinburgh Zoo is designed to answer just that question in an innovative new way - by training chimps to use video touch screens and giving them a special chimp-proof camera.
How will they react to tools which in evolutionary terms are a few million years ahead of them? As chimp specialist Betsy Herrelko finds out, trying to communicate with chimps using video technology has its trials and tribulations.
Friday, January 29, 2010
Lunar Orbit: Perigee and Apogee Moon(s)
The orbit of the Moon is distinctly elliptical with an average eccentricity of 0.0549.
The non-circular form of the lunar orbit causes variations in the Moon's angular speed and apparent size as it moves towards and away from an observer on Earth.
The mean angular daily movement relative to an imaginary observer at the barycenter is 13.176358° to the east. The orientation of the orbit is not fixed in space, but precesses over time.
Elongation
The Moon's elongation is its angular distance east of the Sun at any time. At new moon it is zero and the Moon is said to be in conjunction. At full moon the elongation is 180° and it is said to be in opposition. In both cases the moon is in syzygy, that is, the Sun, Moon and Earth are nearly aligned. When elongation is either 90° or 270° the Moon is said to be in quadrature.
Nodes
The line of nodes of the lunar orbit (the line of the intersection of the plane of the lunar orbit with the plane of the ecliptic) has a retrograde motion, that is, it rotates towards the west (along the ecliptic) at a rate of 19°21′ per year, that is, with a period of 6,793 days or 18.60 years (nutation period).
Thus the node, or point at which the Moon's orbit crosses the ecliptic, moves steadily clockwise (viewed from celestial north), closely aligned with Earth's orbital path but in the opposite direction. The interval of time between the passage of the Moon through the same node is called the draconitic month, and is 27.2122 days. The times of the eclipses depend upon these factors.
Line of Apsides
Perigee is the distance of closest approach, whereas apogee is its farthest recession. The line joining these two points (the line of apsides) has a progressive motion or advances, that is, it slowly rotates counterclockwise in space in the plane of the Moon's orbit, that is, direct motion, making one complete revolution in 3232.575 days or about 8.85 years.
Lunar Standstill
When the ascending node of the moon's orbit coincides with the vernal equinox in the northern hemisphere, the declination of the moon in the sky reaches a maximum at 23°29′ + 5°9′ or 28°36′.
This is called the major standstill. Nine and a half years later, when the descending node has come to the same point, the angle is only 23°28′ − 5°8′ or 18°19′, and the declination of the moon is a minimum. This is the minor standstill.
OBAMA to cancel NASA Moon mission
A White House official confirmed published reports that when next week's budget is proposed, Nasa will get an additional 5.9 billion US dollars over five years.
Some of that money would extend the life of the International Space Station to 2020.
It would also be used to entice companies to build private spacecraft to ferry astronauts to the space station after the space shuttle retires, said the official, who spoke on condition of anonymity.
The money in the President's budget is not enough to follow through with Nasa's plan for flights to the moon, which had been initiated by President George W Bush and has already cost 9.1 billion US dollars.
It all comes down to money. The six-year-old Bush plan sputtered when promised budget increases did not materialise. And now money is a big consideration in Nasa's latest shift in focus.
A new direction for Nasa has been on hold for several months while an independent commission studied options and the White House weighed them.
Mr Obama's choice will be made clear on Monday, when he releases his 2011 budget proposal.
Space policy scholar John Logsdon, who was on an Obama space campaign advisory committee, said Mr Obama is adopting the preferred option of a White House-appointed outside panel of experts last year. That concept includes reliance on a commercial spaceship, a space station that functions for five more years than planned, and a "flexible path" for human space exploration.
That might mean trips to a nearby asteroid, a Martian moon or a brief visit to the moon, instead of the Bush plan for a moon base by the end of the decade.
Giant Laser set to trigger Fusion Reaction
The world's largest laser is approaching the long-sought goal of igniting a fusion reaction that produces more energy than the laser delivers.
Lasers are intended to do this by super-heating a fusion fuel pellet until it implodes, heating and compressing its central core to the temperatures and pressures needed for nuclear fusion.
Past experiments have been plagued by irregular implosions that wasted most of the input energy. But now, researchers led by Brian MacGowan of the Lawrence Livermore National Laboratory in California have managed to squeeze targets of material into spheres rather than pancakes or more lopsided shapes, paving the way for future attempts at fusion.
The work was performed at Livermore's 192-laser beam National Ignition Facility (NIF), which began operating in 2009.
The team used targets that did not contain the key ingredients for fusion – two isotopes of hydrogen known as deuterium and tritium. But the symmetrical implosion of the targets suggests that NIF should be able to ignite fusion with laser pulses of 1.2 to 1.3 megajoules – well below its full 1.8-megajoule capacity.
"From everything we can see, we're on the right path here," Jeff Wisoff, a top NIF manager told New Scientist.
Researchers spent last year slowly cranking up the output of the laser, ultimately reaching a total energy of more than 1 megajoules. Now they're pausing to mount new instruments on the 10-centimetre-thick aluminium target chamber and to install giant concrete doors to contain neutrons they expect to produce in future fusion experiments.
In a few months, they will begin testing a series of new targets designed to assess beam interactions and compression. If all goes well, they could try for fusion ignition by the end of the year.
ESA: Mars express - 7777th Orbit
Mars Express has been in orbit since 25 December 2003, returning a wealth of scientific information and some of the most stunning high-resolution imagery of the Red Planet ever.
This week, the orbiter completed 7777 circuits of the planet and continues to operate flawlessly. Currently, each orbit takes 6 hours and 54 minutes.
ESA: Mars express Auspicious orbit marks run-up to Phobos flyby
The images were acquired with the Super Resolution Channel (SRC) of the High Resolution Stereo Camera (HRSC). The camera took 130 images of the moons on 5 November at 9:14 CET in a span of 1.5 minutes at intervals of 1s, speeding up to 0.5-s intervals toward the end. The image resolution is 110 m/pixel for Phobos and 240 m/pixel for Deimos — Deimos was more than twice as far from the camera.
The Super Resolution Channel of the HRSC uses an additional lens, which has a very narrow field of view of just 0.5°, providing four times the magnification than otherwise providing four times the resolution of the HRSC colour stereo channel. Phobos, the larger of the two moons, orbits closer to the Red Planet, circling it every 7 hours and 39 minutes. It travels faster relative to Mars than the Moon relative to Earth. It was 11800 km from Mars Express when the images were taken. Deimos was 26200 kilometres away.
Credits: ESA/DLR/FU Berlin (G. Neukum)
Human Genome Contains Viral DNA
One was the sheer lack of genes: where we had anticipated perhaps 100,000 there were actually as few as 20,000.
A bigger surprise came from analysis of the genetic sequences, which revealed that these genes made up a mere 1.5 per cent of the genome.
This is dwarfed by DNA deriving from viruses, which amounts to roughly 9 per cent.
On top of that, huge chunks of the genome are made up of mysterious virus-like entities called retrotransposons, pieces of selfish DNA that appear to serve no function other than to make copies of themselves. These account for no less than 34 per cent of our genome.
All in all, the virus-like components of the human genome amount to almost half of our DNA. This would once have been dismissed as mere "junk DNA", but we now know that some of it plays a critical role in our biology. As to the origins and function of the rest, we simply do not know.
The human genome therefore presents us with a paradox. How does this viral DNA come to be there? What role has it played in our evolution, and what is it doing to our physiology? To answer these questions we need to deconstruct the origins of the human genome - a story more fantastic than anything we previously imagined, with viruses playing a bigger part than you might care to believe.
Around 15 years ago, when I was researching my book Virus X, I came to the conclusion there was more to viruses than meets the eye. Viruses are often associated with plagues - epidemics accompanied by great mortality, such as smallpox, flu and AIDS.
I proposed that plague viruses also interact with their hosts in a more subtle way, through symbiosis, with important implications for the evolution of their hosts. Today we have growing evidence that this is true (New Scientist, 30 August 2008, p 38), and overwhelming evidence that viruses have significantly changed human evolution.
Thursday, January 28, 2010
Compton Observatory: Detection of Gamma Ray Bursts
Cosmic gamma ray bursts (GRBs) were discovered by accident in the late 1960's by satellites designed to detect gamma rays produced by atomic bomb tests on Earth.
The GRBs appear first as a brilliant flash of gamma rays, that rises and falls in a matter of minutes. These bursts are often followed by afterglows at X-ray, optical and radio wavelengths.
A major leap forward in understanding the source of cosmic GRBs was made when the Burst and Transient Source Experiment (BATSE) was launched aboard the Compton Gamma Ray Observatory in 1991.
BATSE had an all-sky monitor that was capable of detecting a GRB virtually anywhere in the sky. Over a period of 9 years BATSE recorded thousands of GRBs, about 1 per day. Among other things, these results showed that the bursts occurred at random all over the sky.
If the bursts were associated with objects in our Milky Way Galaxy, they would not show such a universal distribution. Rather, they would be concentrated along the plane of our galaxy like most of the matter in the Milky Way.
The BATSE data was so good that it allowed astronomers to also rule out the possibility that the GRBs might be originating in the halo of our galaxy.
The Observatory was named in honor of Dr. Arthur Holly Compton, who won the Nobel prize in physics for work on scattering of high-energy photons by electrons - a process which is central to the gamma-ray detection techniques of all four instruments.
Read the full article on the Chandra X-ray Observatory here ....
'Superman' vision penetrates opaque glass
Some things we consider opaque – "not able to be seen through", in the New Oxford Dictionary of English definition – are slightly translucent, meaning some light does in fact make it through. However, it is scattered so much by bouncing around such materials' lattice of atoms that physicists thought it was beyond practical use for seeing what is on the other side of the object.
A 2007 experiment that managed to focus light through eggshells and a human tooth demonstrated that might not be so. Now the first simple images have been transmitted through an opaque object and reconstructed on the far side, by physicist Sylvain Gigan and colleagues at École Supérieure de Physique et de Chimie Industrielles in Paris, France.
Read the full article here...
ESA Proba-2 Sun Observation Video
Description
Packed with novel devices and science instruments, Proba-2 is demonstrating technologies for future ESA missions while providing new views of our Sun. The team behind the small satellite now declared themselves extremely happy with its first three months in orbit and unveiled Proba-2’s first solar observations.
Gestalt Laws and Design: Slideshare
What is Gestalt?
When human beings look at a painting or a web page or any complex combination of elements, we see the whole before we see the individual parts that make up that whole. This idea of seeing the whole before the parts and even more the whole becoming more than the sum of its parts is Gestalt.
The German word gestalt can be translated as “shape” or “form” and the term refers to how visual input is perceived by human beings. Gestalt psychology was founded by Max Wertheimer and has been added to over the years by other authors.
Wertheimer’s original observation was that we perceive motion when there is nothing more than a rapid sequence of individual sensory events such as a series of lights flashing in sequence. Imagine a string of Christmas lights. Each light turns on and off in sequence along the string. We see the movement of light from one end of the string to the other, when in reality nothing has moved.
We see something that’s not really there and Wertheimer’s explanation is that we see the effect of the whole event that is not necessarily contained in the sum of the parts.
Route 66: Cassini's Next Look at Titan
Cassini's Next Look At Titan
Sixteen days after last visiting Saturn's largest moon, NASA's Cassini spacecraft returns for another look-see of the cloud-shrouded moon - this time from on high.
While this latest close approach places Cassini more than 6,400 kilometers (3,970 miles) higher above Titan's surface than the Jan. 12 flyby, it should not considered of lesser scientific value. Instead, this high-altitude encounter will provide an opportunity for some of the spacecraft's instruments to gain another unique perspective on this crepuscular world.
During T-66, the Imaging Science Subsystem is set to acquire high-resolution observations during and after closest-approach, covering territory from the trailing hemisphere at high southern latitudes northeast to near-equatorial Adiri.
On the inbound leg, the Visual and Infrared Mapping Spectrometer will have the opportunity to do one stellar occultation. (A stellar occultation occurs when an intervening body - in this case Titan - blocks the light from a star).
Thursday's stellar occultation should allow the Cassini science team to further constrain the composition and the spectral properties of Titan's atmosphere.
Although this latest flyby is dubbed "T66," planning changes early in the orbital tour made this the 67th targeted flyby of Titan. T66 is the 22nd Titan encounter in Cassini's Solstice Mission.
NASA 2010: Final Space Shuttle Year Begins With Last Night Launch
Lift-off is set for 04:39 am (0939 GMT) from the Kennedy Space Center at Cape Canaveral in Florida in what marks the final year of space exploration for the shuttle fleet, which is due to be mothballed at the end of September.
Only five more shuttle flights, including the Endeavour launch, are planned, NASA said in a statement after a meeting of the US space agency's scientists.
During its 13-day mission Endeavour's crew will deliver the US module Tranquility, the last big piece of equipment to be flown to the ISS for installation.
Tranquility will provide extra room for crew members as well as the life support and environmental control systems. It will also help recycle waste water and produce oxygen.
The Endeavour's crew will also carry out three spacewalks during the mission.
Wednesday, January 27, 2010
L'Oceans en Danger! Jacques Perrin et Jacques Cluzaud
Rarement des images auront autant donné l’impression de nager en communion avec les multiples animaux qui peuplent les mers de notre globe. Il faut dire qu’avec Le Peuple Migrateur, Jacques Perrin et Jacques Cluzaud nous avaient fait déjà voler auprès des oiseaux qui entament un long périple lors des changements de saisons. Pour ces deux cinéastes fascinés par la nature, se pencher sur les océans ne pouvait que s’imposer. Le film qui découle de leur démarche, et qui s’intitule très logiquement Océans, sortira en début d’année prochaine sur les écrans européens (bande-annonce ci-dessous).
ESA: Previewing of Marvellous Oceans Video
Oceans, a new film produced by filmmaker Jacques Perrin that captures the mysterious and fascinating marine world like never before, makes its big-screen debut today in cinemas across France, Belgium and Switzerland.
ESA and the European space programme play a major role in the film, showing the importance of space to allow us to understand the evolution of the planet and the impact human activities are having on it.
Oceans cover nearly three-quarters of Earth's surface, yet they remain the least explored territories of our planet. Oceans captures the mysterious and fascinating marine world like never before.
The film highlights the unique advantage that views from space provide us with by showing impressive images of our oceans taken from ESA satellites. With pictures 'speaking a thousand words', the film is the ultimate speech in defense of the planet.
For more video previews and the full article click here....
Tuesday, January 26, 2010
Water woes could undermine Yemen's drive against Al-Qaeda
Impoverished Yemen is reeling under the threat of Al-Qaeda, northern Shiite rebels and southern secessionists, but a lack of water is putting its ancient capital at even greater risk, experts say.
Within a decade -- or even less -- Sanaa could become the first waterless capital in the world, they warn, adding the outlook is also bleak for the rest of this parched country where wells in some regions are already dry.
A conference in London
on Wednesday will discuss Yemen's anti-terrorism drive, but it is unclear whether the water woes that experts say are likely to fuel more insecurity are on the agenda.
Water disputes and riots in this largely tribal nation could squeeze Yemen's struggling government, undermining its ability to remain focused on an increasingly alarming security situation.
The United States and major European powers, concerned about the possible fallout from a resurgent Al-Qaeda, have been pressuring Sanaa to uproot the Islamic militants. Yemen says it needs arms, training and funds to do that.
"The situation in Yemen is rapidly deteriorating in the face of several challenges, all of which have the potential to develop into a serious crisis within the next five years," the Carnegie Endowment for International Peace said in a report last year.
NASA: Avoiding Planetary Asteroid Hits Is A Big Job
The Scope of the Hazard
Near-Earth objects are asteroids and comets that orbit the Sun and approach or cross Earth's orbit. An asteroid or comet about 10 kilometers in diameter struck the Yucatan peninsula 65 million years ago and caused global devastation, probably wiping out large numbers of plant and animal species including the dinosaurs. Objects as large as this one strike Earth only about once every 100 million years on average, the report notes.
NASA has been highly successful at detecting and tracking objects 1 kilometer in diameter or larger, and continues to search for these large objects. Objects down to sizes of about 140 meters in diameter - which NASA has been mandated to survey for - would cause regional damage; such impacts happen on average every 30,000 years, the report says.
While impacts by large NEOs are rare, a single impact could inflict extreme damage, raising the classic problem of how to confront a possibility that is both very rare and very important. Far more likely are those impacts that cause only moderate damage and few fatalities.
Conducting surveys for NEOs and detailed studies of ways to mitigate collisions is best viewed as a form of insurance, the report says. How much to spend on these insurance premiums is a decision that must be made by the nation's policymakers.
Yale Team Finds Neural Thermostat Keeps Brain Running Efficiently
Our energy-hungry brains operate reliably and efficiently while processing a flood of sensory information, thanks to a sort of neuronal thermostat that regulates activity in the visual cortex, Yale researchers have found.
The actions of inhibitory neurons allow the brain to save energy by suppressing non-essential visual stimuli and processing only key information, according to research published in the January 13 issue of the journal Neuron.
"It's called the iceberg phenomenon, where only the tip is sharply defined yet we are aware that there is a much larger portion underwater that we can not see," said David McCormick, the Dorys McConnell Duberg Professor of Neurobiology at Yale School of Medicine, researcher of the Kavli Institute of Neuroscience and co-senior author of the study.
"These inhibitory neurons set the water level and control how much of the iceberg we see. We don't need to see the entire iceberg to know that it is there."
The brain uses the highest percentage of the body's energy, so scientists have long wondered how it can operate both efficiently and reliably when processing a deluge of sensory information.
Most studies of vision have concentrated on activity of excitatory neurons that fire when presented with simple stimuli, such as bright or dark bars. The Yale team wanted to measure what happens outside of the classical field of vision when the brain has to deal with more complex scenes in real life.
By studying brains of animals watching movies of natural scenes, the Yale team found that inhibitory cells in the visual cortex control how the excitatory cells interact with each other.
"We found that these inhibitory cells take a lead role in making the visual cortex operate in a sparse and reliable manner," McCormick said.
Nuclear fission algorithm is created
U.S. Department of Energy scientists say they've created a computer algorithm that allows a substantially enhanced view of nuclear fission.
The Argonne National Laboratory scientists said the algorithm, known as the neutron transport code, enables researchers for the first time to obtain a highly detailed description of a nuclear reactor core.
"The code could prove crucial in the development of nuclear reactors that are safe, affordable and environmentally friendly," laboratory officials said in a statement.
To model the complex geometry of a reactor core currently requires billions of spatial elements, hundreds of angles and thousands of energy groups -- all of which lead to problem sizes with quadrillions of possible solutions, the researchers said. Such calculations exhaust computer memory of the largest machines, they said, and therefore reactor modeling codes typically rely on various approximations.
"The (neutron transport code) is intended to reduce the uncertainties and biases in reactor design calculations by progressively replacing existing multilevel averaging techniques with more direct solution methods based on explicit reactor geometries," said Andrew Siegel, leader of Argonne's reactor simulation group.
Officials said the code has run successfully in some of the world's fastest supercomputers, including the IBM Blue Gene at Argonne and the Cray XT5 at the Oak Ridge National Laboratory.
ESA: Slovenia Joins Space Agency
Slovenia becomes the sixth European country to sign the European Cooperating State Agreement with ESA.
ESA's Director of Legal Affairs and External Relations, Peter Hulsroj, and Slovenian Minister of Higher Education, Science and Technology, Gregor Golobic, signed the agreement at ESTEC, Noordwijk, The Netherlands, on 22 January 2010.
This agreement strengthens Slovenia's relations with ESA and defines the legal basis for developing a Plan for European Cooperating State (PECS) Charter, describing activities, projects and budget for Slovenia's cooperation with ESA. Following the signing ceremony, Mr Golobic visited the ESTEC Test Centre and Concurrent Design Facility.
Hungary was the first country to gain this status in April 2003, with Romania, Poland and Estonia also becoming ECS countries. The Czech Republic, now a full Member State, was the second ECS.
The first visit to ESA of a Slovenian delegation was in May 2006, led by Mr Alojz Peterle (former Slovenian Prime Minister and currently Member of European Parliament). Since then, several steps have been made in cooperation between Slovenia and ESA, and the first Cooperation Agreement was signed in May 2008.
ESA participated, through its Earth Observation Directorate, in the 'Bridging the gap' conference in Portoroz, 14-16 May 2008. An ESA expert team visited Slovenian industrial and research organisations involved in space projects in May 2009, notably the Josef Stefan Institute ('bed rest' studies) and EMO Orodjarna, a supplier for the Ariane 5 programme.
During the coming months, Slovenia will define with ESA the specific areas and projects for cooperation, and the budget for the next five years. Its major participation will be in ESA's Science and Robotic Exploration programme.
Slovenia has a longstanding involvement in astronomy and space science. Herman Potocnik (1892-1929) was a Slovene rocket engineer and pioneer of astronautics.
His book, Das Problem der Befahrung des Weltraums - der Raketen-Motor (The Problem of Space Travel - The Rocket Motor) was published in Berlin in 1928. Potocnik devoted himself to rocketry and space science, set out plans for a permanent human presence in space, with detailed plans for a space station and one of the first calculations of a geostationary orbit.
Jupiter: Difference Between Ganymede And Callisto
Jupiter (right) and the Galilean satellites (right to left) Io, Europa, Ganymede, and Callisto. Cutaways show the interior states of Ganymede and Callisto after many impacts by icy planetesimals during the late heavy bombardment. Colors represent density, with black showing the rocky core (with a density 3 g/cm^3), blue showing mixed ice and rock (densities 1.8 to 1.9 g/cm^3) and white showing rock-free ice.
Differences in the number and speed of cometary impacts onto Jupiter's large moons Ganymede and Callisto some 3.8 billion years ago can explain their vastly different surfaces and interior states, according to research by scientists at the Southwest Research Institute appearing online in Nature Geoscience Jan. 24, 2010.
Ganymede and Callisto are similar in size and are made of a similar mixture of ice and rock, but data from the Galileo and Voyager spacecraft show that they look different at the surface and on the inside. A conclusive explanation for the differences between Ganymede and Callisto has eluded scientists since the Voyager Jupiter encounters 30 years ago.
Dr. Amy C. Barr and Dr. Robin M. Canup of the SwRI Planetary Science Directorate created a model of melting by cometary impacts and rock core formation to show that Ganymede and Callisto's evolutionary paths diverged about 3.8 billion years ago during the Late Heavy Bombardment, the phase in lunar history dominated by large impact events.
"Impacts during this period melted Ganymede so thoroughly and deeply that the heat could not be quickly removed. All of Ganymede's rock sank to its center the same way that all the chocolate chips sink to the bottom of a melted carton of ice cream," says Barr. "Callisto received fewer impacts at lower velocities and avoided complete melting."
Monday, January 25, 2010
NASA: Costa Rica's Turrialba Volcano
Strong, long-lasting volcanic tremors were accompanied by gas plumes over the volcano, and emissions of ash began on January 5th. The “jet-type noise” of gas and ash rushing out of fumaroles was heard several kilometers away. On January 21, 2010, Nacion.com reported that potato and carrot farmers were asked to leave fields near the volcano’s summit due to further increases in gas emissions.
Drug that could reverse Alzheimer’s to be tested on patients
The drug, which tackles a key factor in the development of the disease, is expected to enter the crucial Phase 3 trial – the last stage before seeking regulatory approval – in the latter half of 2010, according to its inventor, Aberdeen University’s Professor Claude Wischik.
Earlier clinical trials of the drug – called remberTM – showed that it could slow progression of Alzheimer’s disease by 84 per cent over 12 months. Furthermore, the effect was sustained over two years. When the results were reported at a conference in Chicago in 2008, they caused worldwide excitement and optimism that, at last, an effective treatment for dementia could be in the pipeline.
But before the drug could move to Phase 3 trials – which will compare it against placebo in larger numbers of patients – millions of dollars in funding have to be raised and regulatory obstacles overcome.
Prof Wischik is optimistic that that ongoing fundraising will permit the Phase 3 trial to begin this year. “This will be a large-scale, international study using around 50 centres,” he said. “We’re moving on substantially from the Phase 2 trial – we’ve beefed up our management team and have really moved on to another level.
“We’re breaking new ground here – the Phase 2 trial provided the first evidence that a drug of this type could arrest progression of the disease, but we believe it can go further than that and perhaps reverse the disease, at least at its early stages.”
The drug acts on the “tangles” which are found in the brains of people with the disease, and which were first described by Alois Alzheimer in 1907. Around two decades ago, Prof Wischik discovered that these tangles were made up of a build up of tau protein, which destroys the brain cells responsible for memory, before going on to kill neurons elsewhere in the brain.
A university spin-out company, TauRx Therapeutics, based in Singapore, developed a novel treatment from a chemical already used in other conditions, which appears to ‘dissolve’ the tangles and halt cognitive decline – the Holy Grail in dementia treatment.
The Phase 2 trial – intended to reveal side-effects as well as efficacy – revealed that the tested form of the chemical worked well at the low and moderate doses, backing the theory that it could arrest the progression of the disease.
It did not work at the highest dose tested due to a problem with the formulation which affected the release of the drug in its active form and this had an impact both on the efficacy and side-effects and limiting the benefit that can be achieved with the older form of the chemical.
Read the full article here at Caledonian Mercury .....
ESA: CryoSat-2 Satellite Prepared for Launch
Initial inspections show the satellite to be in good shape.
Marking the official start of the launch campaign, CryoSat-2 arrived at the Yubileiniy airfield at the launch site on 13 January. The first task was to unload the satellite container and support equipment from the Antonov aircraft, which had carried the cargo from Munich in Germany.
Fortunately, the weather was kind; sunny, around –12°C and a slight breeze, which helped with the job of unloading and transporting the precious cargo by lorry to the integration facilities.
The following day was spent unpacking and setting up the ground support equipment. This equipment includes a lifting beam and the multipurpose trolley, which is used to support the satellite while it is being tested. Once the equipment was set up the satellite could be unpacked and installed on the trolley – an important milestone in the launch campaign.
Read the full article on the ESA site ....
Russia's FSB seeking Israeli drones to Patrol Borders
Russian business newspaper Kommersant reports that the security service, known by its Russian acronym FSB, seeks at least five high-performance Orbiter UAVs from Israel's Aeronautics Defense Systems.
Israel is a world leader in developing and manufacturing advanced UAVs. Its military forces have used them extensively for surveillance of the Palestinian territories in the West Bank and the Gaza Strip, and in Lebanon, its northern neighbor.
It has also used missile-armed UAVs for airstrikes, including the assassination of militant leaders on both fronts in recent years.
The Orbiter has a silent electric motor that reduces detection from the ground. It can carry a payload -- video cameras and transmitters -- of around 3.5 pounds at a maximum altitude of around 8,500 feet for two to three hours.
"That the FSB should express interest in UAVs is not surprising," according to the Washington-based Jamestown Foundation, which monitors global security issues.
"There are a number of locations where they would enhance border security, ranging from the Russian-Kazakh border to potential conflict zones such as Abkhazia, South Ossetia as well as in the North Caucasus.
"The deterioration in the security situation in the North Caucasus is undoubtedly a factor in the timing of the FSB initiative, since special services are at the forefront of combating the rising tide of insurgency."
NASA: WISE Telescope Detecting Near Earth Asteroids
The near-Earth object, designated 2010 AB78, was discovered by WISE Jan. 12. After the mission's sophisticated software picked out the moving object against a background of stationary stars, researchers followed up and confirmed the discovery with the University of Hawaii's 2.2-meter (88-inch) visible-light telescope near the summit of Mauna Kea.
The asteroid is currently about 158 million kilometers (98 million miles) from Earth. It is estimated to be roughly 1 kilometer (0.6 miles) in diameter and circles the sun in an elliptical orbit tilted to the plane of our solar system. The object comes as close to the sun as Earth, but because of its tilted orbit, it is not thought to pass near our planet. This asteroid does not pose any foreseeable impact threat to Earth, but scientists will continue to monitor it.
WISE, which began its all-sky survey on Jan. 14, is expected to find about 100-thousand previously undiscovered asteroids in the Main Belt between Mars and Jupiter, and hundreds of new near-Earth asteroids. It will also spot millions of new stars and galaxies.
Sunday, January 24, 2010
ESA tooling up for ExoMars mission
Establishing whether life ever existed, or is still active on Mars today, is one of the outstanding scientific quests of our time. Both missions in the ExoMars programme will address this important goal. The first spacecraft is the Trace Gas Orbiter, which ESA will build and NASA will launch.
Today, both space agencies issued an Announcement of Opportunity inviting scientists to propose instruments to be carried on the mission. Once all proposals are in, they will be evaluated and the winning teams will be tasked with building the actual hardware.
A Joint Instrument Definition Team has identified a model payload based on current technology, but turning that blueprint into reality is now the job of the scientific community. "We are open to all instrumental proposals so long as they help us achieve our scientific objectives," says Jorge Vago, ESA ExoMars Project Scientist.
The priority for this mission is to map trace gases in the atmosphere of Mars, distinguishing individual chemical species down to concentrations of just a few parts per billion. Of these gases, one in particular attracts special attention: methane.
Discovered on Mars in 2003, it happens to be a possible 'biomarker', a gas that is readily produced by biological activity. Understanding whether the methane comes from life or from geological and volcanic processes takes precedence. "The methane is the anchor point around which the science is to be constructed," says Vago.
Adding to the mystery is that methane was found to be concentrated in just three locations on Mars, and then disappeared much faster from the atmosphere than scientists were expecting. This points to an unknown destruction mechanism much more powerful than any known on Earth. It may also indicate a much faster creation process to have produced such large quantities of the gas in the first place.
MARS is looking at its best right now
Earth and Mars are in an eternal dance with the two parties sometimes close, sometimes very far apart. Both worlds orbit the sun, with Earth doing so more quickly on the inner path. Every 2.1 years, Earth laps Mars, like a race car on the inside track. At that moment, the sun, Earth and Mars are all lined up. Astronomers call it opposition.
During much of January we've been speeding toward Mars in our orbit by an average of 3 miles per second; so Mars has been gradually getting brighter and larger in apparent size.
Mars will pass closest to the Earth at 2:01 p.m. EST during the American afternoon of Jan. 27, just two days before its Jan. 29 opposition, when it will appear to rise at sunset and set at sunrise and will be visible all night.
As a bonus, on opposition night, the Moon, just hours before officially turning full, will sit well off to the right of Mars as they climb the early evening eastern sky.
NASA Working to Boost Speed of Space Communications
View of the Canberra Complex showing the 70m (230 ft.) antenna and the 34m (110 ft.) antennas. The Canberra Deep Space Communications Complex, located outside Canberra, Australia, is one of the three complexes which comprise NASA's Deep Space Network. The other complexes are located in Goldstone, California, and Madrid, Spain
Rovers and deep space probes can forget about quickly posting cool high-definition videos to YouTube, given the painfully slow data transfer rates for most of today's space missions.
But NASA wants to change that by fusing together three aged space communication networks into a much faster, more efficient data network worthy of 21st century missions to the moon, Mars and beyond. And it hopes to do it all without costing taxpayers an extra cent.
NASA's overhaul aims to boost space communication by as much as 50 times faster than today's data transfer rates, so that a Mars mission squeaking by on a few megabits per second might someday get as much as 600 megabits per second, if not more. That could enable far more scientific payoff per mission in the long run.
"Imagine what you can accomplish with a single mission instead of several spacecraft flying over several years to collect the data," said Badri Younes, NASA's deputy associate administrator for Space Communications and Navigation.
An upgraded network might support the very quick upload or download of huge video files the size of an HD YouTube video, as opposed to current capabilities that would struggle to transfer mp3 music files.
Younes worked at NASA's Goddard Space Flight Center for a decade before leaving to join the U.S. Department of Defense. But the U.S. space agency hired him back in August 2007 for the purpose of revolutionizing its space communication networks.
Bigelow Aerospace Building the first Private Space Station
Bigelow Aerospace is pioneering use of expandable space modules. Grouping of modules into Earth orbiting facilities are to be offered for rent or lease to countries and corporate interests. Credit: Bigelow Aerospace
With two prototype modules for a commercial space station already circling the Earth, Bigelow Aerospace is gearing up for a full-scale assault on space.
For the upstart firm, it's about volume — and not entirely in the sense of quantity or number of items sold. The company's expandable module designs are designed to offer low-cost commercial volume in space — for rent or lease — not only to private sector interests, but also to national space agencies.
Entrepreneur Robert Bigelow founded Bigelow Aerospace in 1999. Over the years, the space businessman has invested some $180 million in his vision, drawing from a bank account built on construction and real estate deals, along with money gleaned from his hotel chain, Budget Suites of America.
Entrepreneurial zeal
As "Mr. B" explains, space is no longer viewed as largely the exclusive domain of large governments and satellite telecommunications companies. Emerging as a key ingredient of the future is the rise of the private sector, hungry to spur a new business case for space. An element of that entrepreneurial zeal is the establishment of commercial space habitats and complexes.
NASA Mars: HiRISE pictures on request
If you have an absolute favorite spot on Mars, NASA wants to know. The agency may even take a snapshot for you with its most powerful camera circling the red planet.
NASA is taking public suggestions for photo targets on Mars using the HiRISE camera on its Mars Reconnaissance Orbiter. The "HiWish" project, announced Wednesday, allows the general public to choose a location on Mars from a map on the Internet for HiRISE to photograph.
But there's a catch. Merely asking for a photo won't cut it. Requests must be accompanied with a title for the snapshot and a brief explanation of what scientific benefits may come from the Martian photo shoot. Suggestions also need to be categorized in one of the 18 science themes for the camera's mission at Mars.
The highest-priority suggestions will zoom to the top of the list, project organizers said. There is already a backlog of thousands of targets requested by scientists and students waiting for HiRISE to photograph, they added.
"The HiRISE team is pleased to give the public this opportunity to propose imaging targets and share the excitement of seeing your favorite spot on Mars at people-scale resolution," said HiRISE principal investigator Alfred McEwen of the University of Arizona in a statement.
Earth's Gravitational Pull Threatens Near-Earth Asteroids
Asteroids, such as Itokawa, pictured here, are thought to be more like piles of rubble loosely clung together, than solid chunks of rock. Credit: ISAS/JAXA
steroids may want to think twice before they swing too close to Earth. A new study has found that our planet's gravity can cause seismic tremors, or asteroid-quakes, if the space rocks stray too close.
This process could explain why many space rocks orbiting nearby appear pristine, as if they were covered in a new and clean surface, researchers said.
Normally, asteroids are weather-beaten, their top coats of rock made dirty and reddened by the onslaught of charged particles streaming off the sun during up to 4 billion years or more of wandering the solar system.
"Any part of the surface that's facing into the sun is hit by the solar wind, which damages the mineral grains and turns them red," said the study's lead researcher Richard Binzel of MIT. "An analogy is a sunburn."
Like a sunburn on your skin, the reddening of an asteroid is only skin deep, with fresher material lurking just beneath the sun-drenched surface of the space rock, he added.
But when asteroids approach the Earth, our planet's gravity may induce small quakes that shake up the space rocks, causing the weathered pebbles on their surface to turn over, revealing their cleaner undersides. Asteroids are thought to be more like piles of rubble loosely clung together, than solid chunks of rock, which means even a small tremble could displace surface material.
"All of the particles that got reddened are going to flip over and you're going to have new material that's fresh now out facing the sun," Binzel told SPACE.com. "So it's going to change the color of the asteroid from red to a brighter gray."
The idea has been suggested before, but now Binzel and his colleagues have finally found observational evidence that it's happening.
China: Launches Beidou GPS Satellite system
China has developed a family of boosters over the years, including new development of a heavy-lift launcher to fly by 2011. Credit: China National Space Administration
A Chinese Long March rocket hauled a new navigation satellite to a high-altitude perch over Earth on Saturday, marking the first space launch of the year for the world's space programs.
The Long March 3C rocket blasted off from the Xichang space center at 1612 GMT (11:12 a.m. EST) Saturday, or just after midnight Sunday morning local time, state media reported.
The 180-foot-tall booster flew east from Xichang, which is situated in Sichuan province in southwestern China. The Beidou, or Compass, navigation satellite was placed on a trajectory toward geosynchronous orbit, according to the Xinhua news agency.
The satellite is the third member of the second-generation Beidou constellation. Two spacecraft were launched to medium Earth orbit and geosynchronous orbit in 2007 and 2009, respectively.
First-generation satellites were launched between 2000 and 2007 to test the Beidou concept in space and provide limited services for China.
NASA: Fantastic Close-up of Moon Crater - Tycho
LRO image of Tycho crater. The proposed Constellation site is to the North of the crater's central peak. Credit: NASA/Goddard/Arizona State University
New photographs taken by a satellite in orbit around the moon have revealed one of its most prominent craters in a whole new light.
The moon's Tycho Crater, though average in size, is special because it appears to have formed relatively recently. The vast crater still looks pristine in the new images, while older craters are slowly covered by newer impacts as their features are obscured over the years.
Like all the moon's craters, Tycho is thought to have formed when a space rock slammed into the surface. Since the moon lacks Earth's protective atmosphere, which vaporizes small asteroids on collision courses, even tiny rocks can make a dent on the lunar surface.
The new images were captured by NASA's Lunar Reconnaissance Orbiter (LRO) and released Jan. 14. The robotic spacecraft is on a scouting mission to map the moon's surface in great detail to help plan for the proposed manned trips on the horizon.
Rays of material ejected during the impact are still visible around Tycho, as is the central heap of debris that resulted when melted material flowed back down the crater's slopes and solidified in the middle. Because it is so well preserved, Tycho offers a unique chance to study the mechanics of how craters form, researchers said in a statement.
Tycho is about 53 miles (85 km) in diameter. Without directly sampling rocks from inside the crater, scientists can't be sure how old it is.
One of their best guesses comes from rocks collected by astronauts at the Apollo 17 landing site that may have originated at Tycho and been displaced by the impact. Radiometric age dating of these rocks indicates they formed about 108 million years ago, meaning the Tycho crater may have formed then as well.
"This may still seem old, but compared to the 3.9 billion-year age for many large lunar craters, Tycho is the new kid on the block," LRO researchers said in a statement.
To find the truth about Tycho's age, scientists will need rocks collected inside the crater. These may finally be available soon, since the site has been chosen as a possible landing spot for future manned missions to the moon in the 2020s under NASA's Constellation program.
"Directly sampling material from within the crater would help us learn more about not just when Tycho formed, but the ages of terrains on other planets throughout the solar system," the scientists said.
Saturday, January 23, 2010
Viruses use 'Hive Intelligence' to spread Infection
A tactic familiar from insect behaviour seems to give viruses the edge in the eternal battle between them and their host – and the remarkable proof can be seen in a video.
The video catches viruses only a few hundred nanometres in size in the act of hopping over cells that are already infected. This allows them to concentrate their energies on previously uninfected cells, accelerating the spread of infection fivefold.
Geoffrey Smith and his team of virologists at Imperial College London were curious about the vaccinia virus, and set up a video microscope to watch how the virus spreads through cells.
Vaccinia and Smallpox
Vaccinia was used in the vaccine that rid the world of smallpox some 35 years ago. It doesn't cause disease in humans or any other animal, and its origin is unknown.
Spreading Infection
The traditional idea of how viruses spread goes like this. A virus first enters a cell and hijacks its machinery to make its own viral proteins and replicate. Thousands of replicated viruses then spread to neighbouring cells to wreak havoc.
When Smith watched the vaccinia virus infecting monkey liver cells, he thought that it was spreading far too quickly. "It takes 5 to 6 hours for the virus to replicate, but it was spreading from cell to cell within 1 or 2 hours," he says.
Spread of Vaccinia
Vaccinia is known to spread from cell to cell in a characteristic way. After attaching to the cell membrane of its target, it releases a protein that enters the cell, where it communicates with actin – a protein that helps maintain the cell's structure.
The actin responds by growing longer, and then attaches itself to the virus, still sitting on the surface of the cell, as a so-called "actin tail". This tail helps the virus take off from the cell and find the next victim.
Marking the Virus
Smith's team labelled the virus with green fluorescent protein, and labelled some – but not all – cells with a red marker that tagged the actin. They found, to their amazement, that a virus leaving a cell would travel to another cell and merely bounce off it if it already contained the virus.
Virus Changes
The researchers could tell that a single virus had travelled over more than one cell because some viruses which left a cell with an uncoloured actin tail picked up a red actin tail from another cell. "This means that the viruses can change their actin tails as they bounce along the surfaces of cells," says Smith. "This allows the virus to reach distant cells really quickly."
Smith reckons that two viral proteins which are presented on the surface of the infected cell effectively tell the virus not to bother reinfecting that cell. When he looked at virus strains lacking each of these proteins, the virus spread at the slower rate that would expected without the "bouncing infection" mechanism.
"It's as if the proteins are telling the virus: 'Hey guys, there's no point in coming in here'," says Smith. "If you think about it, it makes sense – it's very Darwinian."
Friday, January 22, 2010
ESA - Observing the Earth - Congo receives help from space after volcano eruption - images
Congo receives help from space after volcano eruption
Fears were also triggered in Goma as rumours circulated that an eruption was imminent at the nearby Nyiragongo volcano, which devastated the city in 2002.
Following the eruption, scientists and local authorities have been using a long series of space images from ESA’s Envisat, together with seismic and helicopter data, to monitor the situation and calm fears of the local population.
Dr Nicolas d’Oreye of GORISK, which is in Congo assisting the Goma Volcano Observatory to collect and process satellite observations and field data, said the satellite images are very useful for managing the crisis.
"As well as helping to validate information from different datasets, the satellite images are providing invaluable information about the situation, such as the details about the lava flow and the fact that the Nyiragongo volcano is not showing any signs of abnormal activity.
Path of lava flow |
Goma, the capital of the North Kivu province, is situated along the southern margin of the lava fields from these volcanoes. Lava from the Nyamulagira (height 3058 m) eruption has been flowing in a direction south and southwest of the volcano, raising concerns that lava could cover the Goma and Sake road within weeks, causing widespread chaos and threatening the local economy.
"Lava flows from Nyamulagira are usually not a direct threat for the population and the infrastructure except when it develops southwards, as it is in this case," explained Dr d’Oreye, a senior scientist at the Geophysics/Astrophysics Department of the National Museum of Natural History in Luxembourg. "In this situation, it is crucial to monitor the flow size, direction and speed for the authorities to be able to make timely decisions."
Lava flows can be mapped by comparing satellite radar images acquired before and after the eruption. In the images, old lava appears bright white. If an area appears white in before images and black in after images, then the ground has changed between acquisitions by the flow of new lava.Thursday, January 21, 2010
NASA Image of the the Day - Gallery
Dunes of Mars
Dunes of sand-sized materials have been trapped on the floors of many Martian craters. This is one example, from a crater in Noachis Terra, west of the giant Hellas impact basin. The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter captured this view on Dec. 28, 2009
Wednesday, January 20, 2010
Tuesday, January 19, 2010
Homeopathy - Didn't realise there was nothing in it
The 10:23 'overdose' event
What is Homeopathy?
Contrary to popular belief, 'homeopathy' is not the same as herbal medicine. Homeopathy is based on three central tenets, unchanged since their invention by Samuel Hahnemann in 1796.
The Law of Similars
The law of similars states that whatever would cause your symptoms, will also cure those same symptoms. Thus, if you find yourself unable to sleep, taking caffeine will help; streaming eyes due to hayfever can be treated with onions, and so on. This so-called law was based upon nothing other than Hahnemann's own imagination. You don't need to have a medical degree to see the flawed reasoning in taking caffeine - a stimulant - to help you sleep; yet caffeine is, even today, prescribed by homeopaths (under the name 'coffea') as a treatment for insomnia.
The Law of Infinitesimals
Following on from his 'law of similars', Hahnemann proposed he could improve the effect of his 'like-cures-like treatments' by repeatedly diluting them in water. The more dilute the remedy, Hahnemann decided, the stronger it will become. Thus was born his 'Law of Infinitesimals'.
Taking a single drop of caffeine and diluting in ninety-nine drops of water creates what is known to homeopaths as one 'centesimal'. One drop of this centesimal added to another ninety-nine drops of water produces a two-centesimal, written as 2C. This 2C caffeine potion is 99.99% water and just 0.01% caffeine. At 3C the dilution is 0.0001% caffeine, at 4C it's 0.000001% caffeine, and so on. Homeopathic remedies are commonly sold at 6C (0.000 000 000 1%) and even 30C (0.000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 1%) dilutions, which homeopaths will often drip onto little balls of sugar to sell.
When these numbers are written out, it's easy to see how absurd they are. At 12C you pass what is known as the Avogadro Limit, the point at which there is likely nothing of your original substance left.
By the time you reach 30C, you have more chance of winning the lottery five weeks running than you have of finding a single caffeine molecule in your homeopathic sleeping draft. It's just ordinary water, dripped onto ordinary sugar.
The Law of Succussion
While transporting his remedies on a horse-drawn carriage, Hahnemann made another 'breakthrough'. He decided that the vigorous shaking of a homeopathic remedy would further increase its potency. This shaking process was named 'succussion'. When ritually preparing a homeopathic remedy, the homeopath will shake or tap the preparation at each stage of dilution, in order to 'potentize' it.
Modern homeopaths believe that this 'potentization' process allows the water to retain the 'memory' or 'vibrations' of the original substance, long after it has been diluted away to nothing. Of course, there is no good scientific evidence to suggest that water has such an ability, nor any indication of how it might be able to use this 'memory' to cure a sick patient.
Does it work?
Despite being rooted in supersition, ritual and sympathetic magick, the laws devised by Hahnemann are still in use by homeopaths today.
For Hahnemann's Laws to be correct, we would have to toss out practically everything we have learned over the past two centuries about biology, pharmacology, mathematics, chemistry and physics. Illnesses are not effectively treated by administering substances which cause similar symptoms; serial dilution and succussion does not 'potentize' a remedy. Water has no memory, nor any way of using one if it did! Homeopathy could never work in the way Hahnemann described it, but does it work at all?
The most comprehensive review of homeopathic treatments ever conducted was published in the medical journal The Lancet in 2005. The paper analysed every clinical investigation then published into the effects of homeopathy, and concluded that any apparent benefits from homeopathic 'treatments' were simply placebo effects. Homeopathy does not work. This conclusion was supported by the Cochrane Collaboration, an independent global network of medical professionals tasked with examining medical research to determine exactly which treatments are effective.