Tuesday, January 31, 2012

Short-term memory is based on synchronized brain oscillations

In each of the two brain regions (IPF and V4) brain activity shows strong oscillations in a certain set of frequencies called the theta-band.

Credit: Stefanie Liebe, MPI for Biological Cybernetics

Holding information within one's memory for a short while is a seemingly simple and everyday task.

We use our short-term memory when remembering a new telephone number if there is nothing to write at hand, or to find the beautiful dress inside the store that we were just admiring in the shopping window.

Yet, despite the apparent simplicity of these actions, short-term memory is a complex cognitive act that entails the participation of multiple .

However, whether and how different brain regions cooperate during memory has remained elusive.

A group of researchers from the Max Planck Institute for in Tübingen, Germany have now come closer to answering this question.

They discovered that oscillations between different brain regions are crucial in visually remembering things over a short period of time.

It has long been known that brain regions in the frontal part of the brain are involved in , while processing of visual information occurs primarily at the back of the brain.

However, to successfully remember visual information over a short period of time, these distant regions need to coordinate and integrate information.

To better understand how this occurs, scientists from the Max Planck Institute of Biological Cybernetics in the department of Nikos Logothetis recorded electrical activity both in a visual area and in the frontal part of the brain in monkeys.

The scientists showed the animals identical or different images within short intervals while recording their brain activity. The animals then had to indicate whether the second image was the same as the first one.

The scientists observed that, in each of the two brain regions, brain activity showed strong oscillations in a certain set of frequencies called the theta-band.

Importantly, these oscillations did not occur independently of each other, but synchronized their activity temporarily: "It is as if you have two revolving doors in each of the two areas.

During working memory, they get in sync, thereby allowing information to pass through them much more efficiently than if they were out of sync," explains Stefanie Liebe, the first author of the study, conducted in the team of Gregor Rainer in cooperation with Gregor Hörzer from the Technical University Graz.

The more synchronized the activity was, the better could the animals remember the initial image. Thus, the authors were able to establish a direct relationship between what they observed in the brain and the performance of the animal. 

NASA IBEX: Video - Glimpses of the Interstellar Material Beyond our Solar System

A great magnetic bubble surrounds the solar system as it cruises through the galaxy.

The sun pumps the inside of the bubble full of solar particles that stream out to the edge until they collide with the material that fills the rest of the galaxy, at a complex boundary called the heliosheath.

On the other side of the boundary, electrically charged particles from the galactic wind blow by, but rebound off the heliosheath, never to enter the solar system. Neutral particles, on the other hand, are a different story.

They saunter across the boundary as if it weren't there, continuing on another 7.5 billion miles for 30 years until they get caught by the sun's gravity, and sling shot around the star.

There, NASA's Interstellar Boundary Explorer lies in wait for them. Known as IBEX for short, this spacecraft methodically measures these samples of the mysterious neighbourhood beyond our home.

IBEX scans the entire sky once a year, and every February, its instruments point in the correct direction to intercept incoming neutral atoms.

IBEX counted those atoms in 2009 and 2010 and has now captured the best and most complete glimpse of the material that lies so far outside our own system.

The results? It's an alien environment out there: the material in that galactic wind doesn't look like the same stuff our solar system is made of.

NASA Launches Blast Off! A New Facebook Game

NASA announced yesterday that it’s launched a new game on Facebook, with a goal of testing people’s knowledge about science, the space program, and pop culture.

The game was developed by Scott Hanger, Todd Powell and Jamie Noguchi of NASA’s Internet Services Group.

The game, called Space Race Blast Off is a pretty straightforward, multi-player trivia game. Players choose an avatar, then compete against two other players to see who can get the most points.

Winners earn achievements in the form of badges. The overall goal of the game is to provide more public outreach for NASA.

“Space Race Blastoff opens NASA’s history and research to a wide new audience of people accustomed to using social media,” said David Weaver, NASA’s associate administrator for communications in the press release. “Space experts and novices will learn new things about how exploration continues to impact our world.”

I tried out the game and am actually ashamed to admit it wasn’t until my fourth round playing that I finally beat my competitors. Which got me a Robert Goddard badge – something I’m quite happy about.

Not only am I a big Goddard fan, but I spent most of my time at my alma mater, WPI, at Goddard Hall – the home of the university’s chemistry and biochemistry programs.

If you’re going to play, be warned. The questions are actually pretty tough. Word of advice if you want to give it a shot: learn your astronauts. That’s definitely my weak point.

Make sure you have a good grasp of the periodic table, too. That said, it’s a fun game to play.

You can check out the game for yourself here.

Space Debris: ISS Orbit Raised to Avoid Collision with China Space Junk

Specialists of Russia's Mission Control Center raised the orbit altitude of the International Space Station (ISS) in the early hours of Sunday to prevent a possible collision with a Chinese satellite fragment, a spokesman for the Center said.

"The maneuver was performed using Zvezda service module engines," the spokesman said.

The altitude of the ISS orbit was raised by 1.7 kilometers to 391.6 kilometers, he said, adding that the maneuver lasted 64 seconds.

NASA earlier reported on its website that 32 hours after Russia's Progress-M-14M docks with the ISS - which occurred at 4.08 am Moscow time (00:08 GMT) on Saturday - a fragment of the Chinese Fengyun-1C weather satellite is likely to pass in dangerous proximity to the space station.

The satellite fragment approached the ISS several times in the past, most recently on January 24, but there was no need to change the station's altitude at that time, the spokesman said.

The aging Fengyun-1C satellite was destroyed in 2007 during Chinese anti-satellite missile tests. Thousands of its fragments have since remained in orbit.

Solar Flares Solution to Vanishing Electrons

Researchers from the University of California, Los Angeles (UCLA) have solved the mystery behind vanishing electrons on Earth. The scientists conducted an experiment which suggested solar flares were the major reason behind the mystery.

During the experiment, the researchers installed three networks of orbiting spacecrafts, positioned at different distances from Earth to catch escaping electrons in the act. The data shows that a majority of the electrons were stripped away from the radiation belt by solar wind particles, when the solar flare reached Earth.

According to the researchers, when flares erupt on the Sun's atmosphere, parts of the magnetized outer layers of the Sun's atmosphere crash onto Earth's magnetic field, thereby triggering geomagnetic storms that are capable of damaging satellites and affecting electrons present on Earth.

The fact that these electrons were missing was discovered back in the early 1960s. Initial hypothesis suggested they were lost to the Earth's atmosphere, while others said they were not permanently lost merely drained of energy (temporarily) so they appeared absent. The mystery has now been solved.

"During the onset of a geomagnetic storm, nearly all the electrons trapped within the radiation belt vanish, only to come back with a vengeance a few hours later," said Vassilis Angelopoulos, a Professor at the UCLA, "It's a puzzling effect."

"This is an important milestone in understanding Earth's space environment," said Drew Turner, an Assistant Researcher at UCLA, "We are one step closer towards understanding and predicting space weather phenomena."

Saturn: Plan to Fly A Nuclear powered Drone craft to Titan

Scientists have proposed a plan to send a nuclear-powered drone to Saturn's moon Titan, which is 10 times more distant from the sun than Earth and has a methane atmosphere that is four times a dense.

Led by BYU professor Jani Radebaugh, the plan is to put the drone in Titan for a year-long flight so it can observe the moon which shares many similarities with the Earth like rivers, oceans, mountains, sand dunes and winds.

"Titan is a really interesting place as far as understanding the processes on the early Earth," said Radebaugh.

"It orbits at a good distance, has organic molecules of carbon and hydrogen, there's energy in the atmosphere and perhaps occasionally water on or near the surface - those are the main things considered necessary for life."

According to the scientists, the proposed drone will operate on a nuclear battery that can power a couple light bulbs.

The battery would power a propeller except when it needed to beam data back to radio telescopes on earth, however, prior to these transmissions, the drone would climb high into Titan's atmosphere.

Power would then shift to the radio cone in the drone's nose as the aircraft glides back down to its usual flight altitude, the researchers explained.

Published in the Experimental Astronomy, Radebaugh and her group noted that while transporting the drone to Titan would take up to 7 years, once there the communication relay time would take a mere 90 minutes.

Titan is of great interest to scientists because it is the only moon in the solar system known to have clouds and a mysterious, thick, planet-like atmosphere.

Recent researches have also found Titan to be more Earth-like than previously thought. Here are some interesting facts about this object in the solar system.

• Titan is the biggest of the 53 known moons orbiting Saturn. It is a cold world enclosed by a thick, hazy atmosphere that is yet to be penetrated by telescopes and cameras.

• Titan is the second largest moon in our solar system with an equatorial radius of 2,575 km (1,600 miles). It's bigger than Earth's Moon and the planet Mercury.
• Titan's surface temperature is about -289 degrees Fahrenheit (-178 degrees Celsius).

• Titan orbits Saturn at a distance of about 1.2 million km (745,000 miles), taking almost 16 days to complete a full orbit.

• Titan was discovered on 25 March 1655 by the Dutch astronomer Christiaan Huygens.

Radebaugh wants to collect the data from Titan to get more information on how the moon's geology has formed.

"One of the main things we're looking for is life or precursors for life. Titan has a lot of molecules made of carbon and hydrogen, there's water ice bedrock, and water volcanoes," Radebaugh said.

"With water, organic molecules, and energy, that's all the ingredients for life. It's a really good place to look for precursory biology," she added.

Monday, January 30, 2012

NASA ISS Image: Western Europe at Night

With hardware from the Earth-orbiting International Space Station appearing in the near foreground, a night time European panorama reveals city lights from Belgium and the Netherlands at bottom center.

The British Isles partially obscured by solar array panels at left, the North Sea at left center, and Scandinavia at right center beneath the end effector of the Space Station Remote Manipulator System or Canadarm2.

The image was taken by the station crew on Jan. 22, 2012.

Image Credit: NASA

Spider Silk Skin can Stop a bullet

Dutch artist Jalila Essaïdi and cell biologist Abdoelwaheb El Ghalbzouri have blended spider silk with human skin to produce material that is three times stronger than kevlar.

In the first clip, the bioengineered skin cushions a bullet fired at half speed. But its resistance has its limits: when shot at a full speed of 329 m/s, the bullet pierces the material and travels through it. The same tests were also performed with piglet skin, human skin and human skin fused with regular silkworm silk, which were all penetrated by bullets of both speeds.

An international team worked together to create the new material. First, transgenic goats and silkworms equipped to produce spider-silk proteins spun out the raw material at the synthetic biology lab at Utah State University. The cocoons were then shipped to South Korea, where they were reeled into thread, before being woven into fabric in Germany. The modified silk was then wedged between bioengineered skin cells developed by biochemist Abdoelwaheb El Ghalbzouri at the Leiden University Medical Center in the Netherlands. After five weeks of incubation, the hybrid skin was ready for target practice.

In addition to exploring the material artistically, Essaïdi is also looking into practical uses, such as skin transplants. Spider silk is already being developed by other teams for high-tech applications, which range from artificial corneas to brain implants.

For more about spider silk spin-offs, check out our full-length feature: "Stretching spider silk to its high-tech limits". Or you might also like to find out about the science behind a lavish golden spider-silk cape, currently on display at the Victoria and Albert Museum in London.

ESA VEGA Launch - Video

'Artis de Marsis' Zoo Mascot in the ESA Cupola

'Artis de Marsis' (Amsterdam zoo mascot) in the ESA Cupola of the ISS.

Credit: ESA/NASA

NASA's Dawn: Does Asteroid Vesta Have Water Ice?

Astronomers from NASA have discovered a giant asteroid - Vesta - that is expected to have water ice. They believe Vesta may have stayed frozen for billions of years. This is contrary to earlier Earth-based observations that the surface of the Vesta is dry.

The information was transmitted from NASA's Dawn spacecraft, which entered into orbit around Vesta in July.

The asteroid is reportedly the second largest object in the asteroid belt between Mars and Jupiter and is approximately 480km (300 miles) in diameter. It doesn't have a permanent shadow because its axis is tilted to roughly 27 degrees, meaning the asteroid sees seasons similar to the ones we experience on Earth. As a result, almost every part of Vesta's surface is expected to see the Sun, at some point during the year.

The average temperature on Vesta is, however, around minus 190 degrees Fahrenheit... the reason why water ice is able to survive in the soil.

According to the astronomers, the presence of water ice on Vesta gives us an idea about the tiny world's formation and evolution, its history of bombardment by comets and its interaction with the environment in surrounding space. Furthermore, the fact that Vesta may have reserves of water ice could lead to a greater understanding of the solar system.

Meanwhile, the Dawn is also investigating the role of water in the evolution of planets, by studying Vesta and Ceres... two bodies in the asteroid belt that are considered remnant protoplanets (young planets whose growth was interrupted when Jupiter formed).

The spacecraft is looking for water using the Gamma Ray and Neutron Detector (GRaND) spectrometer, a data collection process well suited to the Dawn's current low orbit position.

"On average, it's colder at Vesta's poles than near its equator, so in that sense, they are good places to sustain water ice," said Timothy Stubbs from NASA's Goddard Space Flight Center, "But they also see sunlight for long periods of time during the summer seasons, which isn't so good for sustaining ice. So if water ice exists in those regions, it may be buried beneath a relatively deep layer of dry regolith."

"Hopefully, we'll know in the next few months whether the GRaND spectrometer sees evidence for water ice in Vesta's regolith. This is an important and exciting time in planetary exploration," he added.

"Our perceptions of Vesta have been transformed in a few months as the Dawn spacecraft has entered orbit and spiraled closer to its surface," said Lucy McFadden, a planetary scientist at NASA Goddard, "More importantly, our new views of Vesta tell us about the early processes of solar system formation. If we can detect evidence for water beneath the surface, the next question will be is it very old or very young, and that would be exciting to ponder."

ESA INTEGRAL: reveals new facets of the Vela pulsar wind nebula

This image shows the Vela pulsar wind nebula as observed with ESA's INTEGRAL observatory (blue pixellated image) and with other high-energy astronomical facilities (coloured contours).

The INTEGRAL image shows emission detected at hard X-ray energies, between 18 and 40 keV, with the IBIS imager on board INTEGRAL, after subtraction of the point-like source corresponding to the inner nebula.

The contours show soft X-ray emission detected by the German ROSAT telescope between 0.5 and 2 keV (green) and by the Birmingham Spacelab 2 telescope between 2.5 and 12 keV (cyan), and very-high energy gamma-ray emission detected with the H.E.S.S. Telescopes above 1 TeV (magenta).

The Vela pulsar wind nebula is a cloud of highly energetic electrons and positrons that are injected by the pulsar into its surroundings and radiate across the electromagnetic spectrum. The location of the Vela pulsar is marked with a cross.

The image measures roughly two degrees on the horizontal side. North is up and East is to the left. Copyright: ESA/INTEGRAL/IBIS-ISGRI/F. Mattana et al./ROSAT/H.E.S.S. /Spacelab 2.

Russia to postpone next manned space launches

Russia is set to pospone the next two manned launches for the International Space Station (ISS) for several weeks due to technical problems with the Soyuz spaceship, an industry source told Interfax Friday.

The source told Interfax that the Soyuz TMA-04M vessel had not withstood tests to its pressure chamber ahead of the planned mission on March 30 and the first flight would be postponed to mid-April or the first half of May.

"This re-entry capsule now cannot be used for manned spaceflight," the source said.

That mission would fly with the re-entry capsule that was due to go up on the next mission on May 30 and as a result that mission would also likely be postponed to the middle or end of June.

The re-entry capsule goes inside the spacecraft and is the portion that eventually returns the astronauts to Earth when the mission is over.

Russia now has sole reponsibility for taking US and other international astronauts to the ISS following the withdrawal of the US space shuttle but its own space programme has been hit by a string of problems in the last months.

Sunday, January 29, 2012

We Were Wanderers on a Prehistoric Earth - Film

We Were Wanderers On A Prehistoric Earth from James W Griffiths on Vimeo.

“We were wanderers on a prehistoric earth,” says the narrator Marlow in Joseph Conrad’s Heart of Darkness, “on an earth that wore the aspect of an unknown planet.

We could have fancied ourselves the first of men taking possession of an accursed inheritance, to be subdued at the cost of profound anguish and of excessive toil.”

The palpable menace that permeates Conrad’s classic novella has been edited out of the narration in this short film, made for Tourism Malaysia by British filmmaker James W. Griffiths.

What remains is a poetic sense of wonder for a natural world that is no longer frightening, no longer in need of being subdued.

In the original, the twisting and turning sentences are like a microcosm of a journey up the winding Congo River, into the metaphorical darkness that lies at the heart of all men. Out of the stillness of the page, Conrad’s imagination washes over us in a rolling wave of words:

The great wall of vegetation, an exuberant and entangled mass of trunks, branches, leaves, boughs, festoons, motionless in the moonlight, was like a rioting invasion of soundless life, a rolling wave of plants, piled up, crested, ready to topple over the creek, to sweep every little man of us out of his little existence. And it moved not.

Griffiths can be forgiven for defanging Conrad. We Were Wanderers on a Prehistoric Earth is a beautiful film, a quiet meditation on the unspoiled rainforest of West Malaysia shot in November by cinematographer Christopher Moon, who also collaborated with Griffiths on last year’s award-winning Nokia cellphone film Splitscreen.

The music is by Lennert Busch, the sound design is by Mauricio d’Orey, and Conrad’s words are spoken by Terry Burns.

Genetic study links body clock receptor to diabetes

A study published in Nature Genetics today has found new evidence for a link between the body clock hormone melatonin and type 2 diabetes.

The study found that people who carry rare genetic mutations in the receptor for melatonin have a much higher risk of type 2 diabetes.

The findings should help scientists to more accurately assess personal diabetes risk and could lead to the development of personalised treatments.

Previous research has found that people who work night shifts have a higher risk of type 2 diabetes and heart disease. Studies have also found that if volunteers have their sleep disrupted repeatedly for three days, they temporarily develop symptoms of diabetes.

The body's sleep-wake cycle is controlled by the hormone melatonin, which has effects including drowsiness and lowering body temperature.

In 2008, a genetic study led by Imperial College London discovered that people with common variations in the gene for MT2, a receptor for melatonin, have a slightly higher risk of type 2 diabetes.

The new study reveals that carrying any of four rare mutations in the MT2 gene increases a person's risk of developing type 2 diabetes six times.

The release of insulin, which regulates blood sugar levels, is known to be regulated by melatonin. The researchers suggest that mutations in the MT2 gene may disrupt the link between the body clock and insulin release, leading to abnormal control of blood sugar.

Professor Philippe Froguel, from the School of Public Health at Imperial College London, who led the study, said: "Blood sugar control is one of the many processes regulated by the body's biological clock.

This study adds to our understanding of how the gene that carries the blueprint for a key component in the clock can influence people's risk of diabetes.

"We found very rare variants of the MT2 gene that have a much larger effect than more common variants discovered before. Although each mutation is rare, they are common in the sense that everyone has a lot of very rare mutations in their DNA. Cataloguing these mutations will enable us to much more accurately assess a person's risk of disease based on their genetics."

In the study, the Imperial team and their collaborators at several institutions in the UK and France examined the MT2 gene in 7,632 people to look for more unusual variants that have a bigger effect on disease risk.

They found 40 variants associated with type 2 diabetes, four of which were very rare and rendered the receptor completely incapable of responding to melatonin. The scientists then confirmed the link with these four variants in an additional sample of 11,854 people.

Professor Froguel and his team analysed each mutation by testing what effect they have on the MT2 receptor in human cells in the lab. The mutations that completely prevented the receptor from working proved to have a very big effect on diabetes risk, suggesting that there is a direct link between MT2 and the disease.

More information: A. Bonnefond et al. 'Rare MTNR1B variants impairing melatonin receptor 1B function contribute to type 2 diabetes' Nature Genetics, published online 29 January 2012.

Expedition 26 Soyuz Landing: Soyuz TMA-01M spacecraft

Russian support personnel work to help get crew members out of the Soyuz TMA-01M spacecraft shortly after the capsule landed with Expedition 26 Commander Scott Kelly and Flight Engineers Oleg Skripochka and Alexander Kaleri near the town of Arkalyk, Kazakhstan on Wednesday, March 16, 2011.

You might have noticed in post-landing pictures that nobody approaches the “bottom” part of the Soyuz descent module. Ever wondered why?

Many people have suggested that it might be very hot. In fact, that is not the case. 

The real heat shield is ejected at an altitude of ca. 5,5 km when the capsule is already hanging under the parachute.

Others have suggested that there might be a danger of accidental firing of the retrorockets. 

Although this sounds like a reasonable suggestion, we are not aware that this presents a risk.

These are two sources of danger that we know of:

1) The gamma-ray altimeter
This device is responsible for generating a signal before ground impact (ca 0,74m) that causes retrorockets to fire

2) Antenna deployment
There are three UHF antennas on the bottom of the descent module. When the descent modules comes to a stop laying on its side, the highest one of the three is automatically deployed eight minutes after ground contact, or earlier by the crew. 

For deployment, the panels covering the antennas are shot away by explosive charges. In case of positive contact with the rescue squad, the crew is typically told to inhibit further antenna deployment; however, a residual danger remains, hence the Keep-Out-Zone.

Commander Scott Kelly: Expedition 26 Soyuz Landing

Expedition 26 Commander Scott Kelly listens to reporters questions while wearing a traditional Kazakh hat at the Kustanay, Kazakhstan airport on Wednesday, March 16, 2011 after he and fellow crew members Alexander Kaleri and Oleg Skripochka landed in their Soyuz TMA-01M capsule near the town of Arkalyk, Kazakhstan.

NASA Astronaut Kelly, Russian Cosmonauts Skripochka and Kaleri are returning from almost six months onboard the International Space Station where they served as members of the Expedition 25 and 26 crews. Photo Credit: (NASA/Bill Ingalls)

Expedition 26 Commander Scott Kelly performs the traditional sighing of the helicopter that flew him from Arkalyk to Kustanay, Kazakhstan after he and Expedition 26 Flight Engineers Oleg Skripochka and Alexander Kaleri landed in their Soyuz TMA-01M capsule near the town of Arkalyk, Kazakhstan on Wednesday, March 16, 2011.

Expedition 26 Soyuz Landing - Alexander Kaleri

Expedition 26 Flight Engineer Alexander Kaleri listens to reporters questions while wearing a traditional Kazakh hat at the Kustanay, Kazakhstan airport on Wednesday, March 16, 2011 after he and fellow crew members Scott Kelly and Oleg Skripochka landed in their Soyuz TMA-01M capsule near the town of Arkalyk, Kazakhstan. 

NASA Astronaut Kelly, Russian Cosmonauts Skripochka and Kaleri are returning from almost six months onboard the International Space Station where they served as members of the Expedition 25 and 26 crews. Photo Credit: (NASA/Bill Ingalls)

Expedition 26 Soyuz Landing - Oleg Skripochka

Expedition 26 Flight Engineer Oleg Skripochka listens to reporters questions in traditional Kazakh dress at the Kustanay, Kazakhstan airport on Wednesday, March 16, 2011 after he and fellow crew members Scott Kelly and Alexander Kaleri landed in their Soyuz TMA-01M capsule near the town of Arkalyk, Kazakhstan.

NASA Astronaut Kelly, Russian Cosmonauts Skripochka and Kaleri are returning from almost six months onboard the International Space Station where they served as members of the Expedition 25 and 26 crews. Photo Credit: (NASA/Bill Ingalls)

Expedition 26 Soyuz Landing - Kazakhstan

Russian support personnel work to help get crew members out of the Soyuz TMA-01M spacecraft shortly after the capsule landed with Expedition 26 Commander Scott Kelly and Flight Engineers Oleg Skripochka and Alexander Kaleri near the town of Arkalyk, Kazakhstan on Wednesday, March 16, 2011.

A Russian all terrain vehicle (ATV) takes Expedition 26 Commander Scott Kelly to a helicopter from the Soyuz TMA-01M spacecraft shortly after the capsule landed with Kelly and Expedition 26 Flight Engineers Oleg Skripochka and Alexander Kaleri near the town of Arkalyk, Kazakhstan on Wednesday, March 16, 2011.

NASA Astronaut Kelly, Russian Cosmonauts Skripochka and Kaleri are returning from almost six months onboard the International Space Station where they served as members of the Expedition 25 and 26 crews. Photo Credit: (NASA/Bill Ingalls)

Expedition 26 Commander Scott Kelly is helped as he exits a Russian all terrain vehicle (ATV) that delivered him to a helicopter from the Soyuz TMA-01M spacecraft shortly after the capsule landed with Kelly and Expedition 26 Flight Engineers Oleg Skripochka and Alexander Kaleri near the town of Arkalyk, Kazakhstan on Wednesday, March 16, 2011.

NASA Astronaut Kelly, Russian Cosmonauts Skripochka and Kaleri are returning from almost six months onboard the International Space Station where they served as members of the Expedition 25 and 26 crews. Photo Credit: (NASA/Bill Ingalls)

Saturday, January 28, 2012

Orbital Space debris update

The latest Orbital Debris Quarterly News has the good news that, barring another satellite collision or other debris-creating event, the number of catalogued debris should drop over the next two years.

The deliberate destruction of the Fengyun-1C satellite in January 2007 created 3,218 pieces of trackable debris, and only about 200 of those have re-entered the atmosphere.

As the solar activity increases leading up to solar maximum in 2013, more of that debris should be cleared out.

NB: Readers in the northern latitudes should look out for more auroras.

Speaking of space debris, an experiment from 1963 deliberately placed millions of tiny copper needles in medium Earth orbit.

Project West Ford created an artificial ionosphere to help the military, back in the days before communication satellites.

The needles were 0.7 inches long and less than half the diameter of human hair (17.8 micrometers).

These were the right size dipole antennas for the 8 GHz wavelength used in the study.

Most of them re-entered the atmosphere by 1970, but there are still some in orbit today.

Electric fields (blue) and magnetic fields (red) radiated by a dipole antenna.

A spacecraft from an earlier attempt in 1961 is also still in orbit. Protests over this experiment led to the addition of a consultation clause in the 1967 Outer Space Treaty. 

The result was, basically, all nations should sumit controversial proposals to the group before they did something that might wreck space for the rest of us.

If they had introduced more of these orbiting dipole antennas into the Earth's atmosphere, they could have wrecked global radio and microwave telescope observations.

World’s Most Powerful X-Ray Laser Created

Scientists from the Oxford University in the UK and the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory have invented a powerful X-ray laser - the Linac Coherent Light Source (LCLS).

For the first time, this laser will allow the heating of matter up to 2 million degrees Celsius, in a controlled setting.

The researchers tested the laser on a piece of aluminum foil and created hot dense matter (or a solid plasma).

The process of heating took less than a trillionth of a second.

According to the scientists, this represents a major step forward in understanding the composition of the more extreme forms of matter found in stars and giant planets; this could also help in experiments aimed at recreating the nuclear fusion process that powers the Sun.

"The LCLS X-ray laser is a truly remarkable machine," said Sam Vinko, a postdoctoral researcher at Oxford University, "Making extremely hot, dense matter is important scientifically if we are ultimately to understand the conditions that exist inside stars and at the center of giant planets within our own solar system and beyond."

"The LCLS, with its ultra-short wavelengths of X-ray laser light, is the first that can penetrate a dense solid and create a uniform patch of plasma - in this case a cube one-thousandth of a centimeter on a side - and probe it at the same time," said Bob Nagler from the SLAC.

"Those 60 hours when we first aimed the LCLS at a solid were the most exciting 60 hours of my entire scientific career," said Justin Wark, also from Oxford, "LCLS is really going to revolutionize the field, in my view."

Friday, January 27, 2012

Chandra X-Ray Image: Dark Energy

The composite image on the left is of the galaxy cluster Abell 85, located about 740 million light years from Earth.

The purple emission is multi-million degree gas detected in X-rays by NASA's Chandra X-ray Observatory and the other colors show galaxies in an optical image from the Sloan Digital Sky Survey.

This galaxy cluster is one of 86 observed by Chandra to trace how dark energy has stifled the growth of these massive structures over the last 7 billion years. Galaxy clusters are the largest collapsed objects in the Universe and are ideal for studying the properties of dark energy, the mysterious form of repulsive gravity that is driving the accelerated expansion of the Universe.

The illustration above shows snapshots from a simulation by Volker Springel, representing the growth of cosmic structure when the Universe was 0.9 billion, 3.2 billion and 13.7 billion years old (now).

This shows how the Universe has evolved from a smooth state to one containing a vast amount of structure.

Gas is shown in these snapshots, where the yellow regions are stars and the brightest structures are galaxies and galaxy clusters.

The growth of these structures was initially driven only by the attractive force of gravity, but then later there was competition with the repulsive force of dark energy.

Understanding the nature of dark energy is one of the biggest problems in science. Possibilities include the cosmological constant, equivalent to the energy of empty space, a modification in general relativity on the largest scales, or a more general physical field.

To help decide between these options, Chandra was used to study the increase in mass of galaxy clusters with time over the last 7 billion years.

The results are remarkably consistent with those from previous results that measure the expansion of the Universe using distance measurements, revealing that general relativity works as expected on large scales.

The cluster work, in combination with other studies, also provides the strongest evidence to date that dark energy is the cosmological constant, or that `nothing weighs something'.

Chandra Image: Abell 3376

Two different teams have reported using Chandra observations of galaxy clusters to study the properties of gravity on cosmic scales and test Einstein's theory of General Relativity.

Such studies are crucial for understanding the evolution of the universe, both in the past and the future, and for probing the nature of dark energy, one of the biggest mysteries in science.

This composite image of the galaxy cluster Abell 3376 shows X-ray data from the Chandra X-ray Observatory and the ROSAT telescope in gold, an optical image from the Digitized Sky Survey in red, green and blue, and a radio image from the VLA in blue.

The "bullet-like" appearance of the X-ray data is caused by a merger, as material flows into the galaxy cluster from the right side. The giant radio arcs on the left side of the image may be caused by shock waves generated by this merger.

The growth of galaxy clusters like Abell 3376 is influenced by the expansion rate of the universe - controlled by the competing effects of dark matter and dark energy - and by the properties of gravity over large scales.

By contrast, observations of supernovas or the large-scale distribution of galaxies, which measure cosmic distances, depend only on the expansion rate of the universe and are not sensitive to the properties of gravity.

In the first of the new studies of gravity, an alternative theory to General Relativity called "f(R) gravity" was tested.

In this theory, the acceleration of the expansion of the universe does not come from an exotic form of energy but from a modification of the gravitational force.

Mass estimates of galaxy clusters in the local universe were compared with model predictions for f(R) gravity.

Data from geometrical studies, such as supernova work, were also used. Using this comparison between theory and observation, no evidence was found that gravity is different from General Relativity on scales larger than 130 million light years.

This limit corresponds to a hundred-fold improvement on the bounds of the modified gravitational force's range that can be set without using the cluster data.

In the second study, a comparison was made between X-ray observations of how rapidly galaxy clusters have grown over cosmic time to the predictions of General Relativity.

Once again, data from geometrical studies such as distances to supernovas and galaxy clusters were incorporated.

Nearly complete agreement was seen between observation and theory, arguing against any alternative gravity models with a different rate of growth.

In particular "DGP gravity" (named after its inventors Gia Dvali, Gregory Gabadadze, and Massimo Porrati) predicts a slower rate of cluster growth than General Relativity, because gravity is weakened on large scales as it leaks into an extra dimension. Like f(R) gravity, the DGP model is designed to avoid the need for an exotic form of energy causing cosmic acceleration.

Chandra observations of galaxy clusters have previously been used to show that dark energy has stifled the growth of these massive structures over the last 5 billion years and to provide independent evidence for the existence of dark energy by offering a different way to measure cosmic distances.

Near Earth Asteroid's near-miss

An Asteroid, estimated to be about 36ft in diameter, will pass within around 37,000 miles of the Earth at 4pm.

Although the asteroid – named 2012 BX34 – will travel past less than a fifth of the distance to the Moon, experts said there is no cause for concern.

"It's one of the closest approaches recorded," said Gareth Williams, associate director of the US-based Minor Planet Center.

"It makes it in to the top 20 closest approaches, but it's sufficiently far away ... that there's absolutely no chance of it hitting us," he told the BBC.

The asteroid's path makes it the closest space-rock to pass by the Earth since object 2011 MD in June 2011.

arlier estimates put the asteroid's closest distance at as little as 12,000 miles, near the distance at which geostationary satellites reside, but observations overnight showed it will pass at a more comfortable distance.

Although the asteroid will not be visible to the naked eye, Dr Williams said that keen backyard astronomers could get a look.

ESA: First Vega rocket assembled on launch pad - images

ESA’s new Vega rocket is now fully assembled on its launch pad. Final preparations are in full swing for the rocket’s inaugural flight.

Flight VV01 will lift off from the new Vega launch site at Europe’s Spaceport in Kourou, French Guiana, carrying nine satellites into orbit: the LARES laser relativity satellite and ALMASat-1 from ASI with seven CubeSats from European Universities.

Credits: ESA - S. Corvaja, 2012

Vega's upper composite, comprising LARES, ALMASat-1, seven CubeSats and the fairing, was transferred to the pad on 24 January and added to the vehicle at Europe's Spaceport in French Guiana.

Credits: ESA - M. Pedoussaut, 2012

Vega's upper composite, comprising LARES, ALMASat-1, seven CubeSats and the fairing, was transferred to the pad on 24 January and added to the vehicle at Europe's Spaceport in French Guiana.

Credits: ESA - M. Pedoussaut, 2012

Bus-Size Near Earth Asteroid Buzzes Earth in Close Flyby

A small asteroid the size of a city bus zoomed between Earth and the moon's orbit Friday (Jan. 25) just days after its discovery, but it never posed a threat to our planet, NASA says.

The asteroid 2012 BX34 passed within 36,750 miles (59,044 kilometers) of Earth when it made its closest approach at 10:30 a.m. EST (1530 GMT). The space rock is about 37 feet (11 meters) wide and would have broken apart in Earth's atmosphere long before it reached the ground, if it had reached the planet at all, NASA scientists said.

"Asteroid 2012 BX34 is small," astronomers with NASA's Asteroid Watch at the Jet Propulsion Laboratory in Pasadena, Calif., said in a Twitter message. "It wouldn't get through our atmosphere intact even if it dared to try."

The space rock passed Earth at a distance that is only about 0.17 times that between the Earth and the moon. For comparison, the moon typically orbits Earth at a distance of about 240,000 miles (386,000 km).

Panoramic view of SpaceX ship Interior - Dragon

Click on the Image to visit the SpaceX Panoramic website.

Dragon is a free-flying, reusable spacecraft being developed by SpaceX under NASA's Commercial Orbital Transportation Services (COTS) program.

Initiated internally by SpaceX in 2005, the Dragon spacecraft is made up of a pressurized capsule and unpressurized trunk used for Earth to LEO transport of pressurized cargo, unpressurized cargo, and/or crew members.

The Dragon spacecraft is comprised of 3 main elements:
  • the Nosecone, which protects the vessel and the docking adaptor during ascent; 
  • the Spacecraft, which houses the crew and/or pressurized cargo as well as the service section containing avionics, the RCS system, parachutes, and other support infrastructure; and 
  • the Trunk, which provides for the stowage of unpressurized cargo and will support Dragon’s solar arrays and thermal radiators.
In December 2008, NASA announced the selection of SpaceX’s Falcon 9 launch vehicle and Dragon spacecraft to resupply the International Space Station (ISS) when the Space Shuttle retires.

The $1.6 billion contract represents a minimum of 12 flights, with an option to order additional missions for a cumulative total contract value of up to $3.1 billion.

Though designed to address cargo and crew requirements for the ISS, as a free-flying spacecraft Dragon also provides an excellent platform for in-space technology demonstrations and scientific instrument testing.

SpaceX is currently manifesting fully commercial, non-ISS Dragon flights under the name “DragonLab”. DragonLab represents an emergent capability for in-space experimentation.

Dragon Spacecraft with Solar Panels deployed

Dragon Highlights:

  • Fully autonomous rendezvous and docking with manual override capability in crewed configuration
  • 6,000 kg (13,228 lbs) payload up-mass to LEO; 3,000 kg (6,614 lbs) payload down-mass
  • Payload Volume: 10 m3 (350 ft3) pressurized, 14 m3  (490 ft3) unpressurized
  • Supports up to 7 passengers in Crew configuration
  • Two-fault tolerant avionics system with extensive heritage
  • Reaction control system with 18 MMH/NTO thrusters designed and built in-house; these thrusters are used for both attitude control and orbital maneuvering
  • 1290 kg of propellant supports a safe mission profile from sub-orbital insertion to ISS rendezvous to reentry
  • Integral common berthing mechanism, with LIDS or APAS support if required
  • Designed for water landing under parachute for ocean recovery
  • Lifting re-entry for landing precision & low-g’s
  • Ablative, high-performance heat shield and sidewall thermal protection
To ensure a rapid transition from cargo to crew capability, the cargo and crew configurations of Dragon are almost identical, with the exception of the crew escape system, the life support system and onboard controls that allow the crew to take over control from the flight computer when needed.

This focus on commonality minimizes the design effort and simplifies the human rating process, allowing systems critical to Dragon crew safety and ISS safety to be fully tested on uncrewed demonstration flights.

For cargo launches the inside of the spacecraft is outfitted with a modular cargo rack system designed to accommodate pressurized cargo in standard sizes and form factors.

For crewed launches, the interior is outfitted with crew couches, controls with manual override capability and upgraded life-support.

To Read More about the Dragon visit the SpaceX website

Vega: ESA's new small launcher - YouTube

Building Costs are being kept to a minimum by using advanced low-cost technologies and existing production facilities used for Ariane launchers, making access to space easier, quicker and cheaper.

Thursday, January 26, 2012

ESA ESO VLT: Ancient Galaxies Snapped

Light traveling for 10 billion years now gives astronomers a glimpse into the largest galaxies in the Universe.

Found in the Fornax constellation, these galaxies (highlighted in red) burst on the cosmic scene with very rapid, intense star formation.

MARS HiRISE Image: Very Fresh Impact Crater Superposing a Wrinkle Ridge in Hesperia Planum

The ridge captured in this HiRISE image is called a wrinkle ridge.

This wrinkle ridge is located in Hesperia Planum, a region of over two million square kilometers (over 770,000 square miles) in the southern highlands of Mars.

It is located northwest of the Hellas basin and adjacent to Tyrrhena Patera and contains abundant orthogonal and intersecting wrinkle ridges.

Wrinkle ridges are long, winding topographic highs and are often characterized by a broad arch with superposed narrow asymmetric ridges. These features have also been identified on the Moon, Mercury, and Venus.

Their origin is attributed to horizontal compression or shortening of the crust due to faulting and folding. They commonly have asymmetrical cross sectional profiles and an offset in elevation on either side of the ridge.

Superposing or located on top of the wrinkle ridge, is a very fresh impact crater. We can tell that this crater is fresh because of its relatively sharp or crisp rim and unmodified shape.

If you look closely, you can see faint rays of relatively fine material, boulders, and smaller secondary craters radiating from the crater and superposing the wrinkle ridge and older surrounding craters.

NASA Mars orbiter HiRise Image: Wind's handiwork

Some images of stark Martian landscapes provide visual appeal beyond their science value, including a recent scene of wind-sculpted features from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

The scene shows dunes and of various shapes and sizes inside an impact crater in the Noachis Terra region of southern Mars.

Patterns of dune erosion and deposition provide insight into the sedimentary history of the area.

The has been examining Mars with six science instruments since 2006.

Now in an extended mission, the orbiter continues to provide insights about the planet's ancient environments and about how processes such as wind, and seasonal frosts are continuing to affect the Martian surface today.

This mission has returned more data about Mars than all other orbital and surface missions combined.

More than 20,600 images taken by HiRISE are available for viewing on the instrument team's website: http://hirise.lpl.arizona.edu .

Each observation by this telescopic camera covers several square miles, or square kilometers, and can reveal features as small as a desk.

More information: For more information about the Mars Reconnaissance Orbiter, see http://www.nasa.gov/mro .

ESA’s CubeSats near the end of a five year journey

Xatcobeo, the CubeSat from University of Vigo and INTA, shown here prior to it's launch.

Credits: Universidade de Vigo / INTA

26 January 2012
The excitement is mounting, not only at the launch site in Kourou, French Guiana, but also in universities across Europe, as ESA's Vega launch vehicle is prepared for its maiden flight.

Among the payloads on board Europe's latest rocket are seven student-built CubeSats sponsored by ESA.

The story of the ESA CubeSats – dubbed the 'ESA Cubs' - began in May 2007, when the Agency decided to include an educational payload, including up to six CubeSats, on the first flight of Vega.

This was followed in January 2008 by the first dedicated CubeSat workshop to be held at European level.

"We didn’t know what to expect, since CubeSat missions were only just starting to become popular amongst universities at that time," said Roger Walker, the Head of Education Projects at the ESA Education Office.

"The level of interest was amazing, with more than 120 people attending the workshop. We were also surprised by the diversity of the projects that were put forward, demonstrating the high creativity of the CubeSats community.

In the end we selected 24 student teams to present their ideas during the workshop at the European Space Research and Technology Centre (ESTEC), in the Netherlands."

Read more here at ESA website

NASA MARS Rover Opprtunity: Greeley Haven

This NASA image is a mosaic of images taken in mid-January 2012 showing the windswept vista northward to northeastward from the location where NASA's Mars Exploration Rover Opportunity is spending its fifth Martian winter, an outcrop informally named "Greeley Haven."

The view includes sand ripples and other wind-sculpted features in the foreground and mid-field.


NASA Earth: The Blue Marble

A 'Blue Marble' image of the Earth taken from the VIIRS instrument aboard NASA's most recently launched Earth-observing satellite - Suomi NPP.

This composite image uses a number of swaths of the Earth's surface taken on January 4, 2012.

The NPP satellite was renamed 'Suomi NPP' on January 24, 2012 to honor the late Verner E. Suomi of the University of Wisconsin.

Suomi NPP is NASA's next Earth-observing research satellite. It is the first of a new generation of satellites that will observe many facets of our changing Earth.

Suomi NPP is carrying five instruments on board. The biggest and most important instrument is The Visible/Infrared Imager Radiometer Suite or VIIRS.

Image Credit: NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring

Laser first: Solves the puzzle of how the Universe got its magnetism

Scientists have demonstrated for the very first time how a laser can be used to stimulate the formation of magnetic fields, similar to those thought to be involved in the formation of the very first galaxies.

The findings published in Nature (26 January 2012) could help solve the riddle of how the Universe originally got its magnetism.

Magnetic fields exist throughout galactic and intergalactic space and in the stars and planets.

The magnetic fields in our solar system are important, since they shield us from the harmful effects of cosmic rays allowing life to thrive.

What is puzzling is how they were originally created. A way of creating magnetic fields without a magnet has long been theorised, but never before has the process been demonstrated.

A team, led by Oxford University physicists, have used a high-power laser to explode a rod of carbon, similar to pencil lead, in helium gas.

The explosion was designed to mimic the cauldron of plasma – an ionized gas containing free electrons and positive ions – out of which the first galaxies formed.

It was designed to prove a theory, known as the ‘Biermann battery effect’ that demonstrated how magnetic fields could form where none had existed before.

The team found that within a microsecond of the explosion strong electron currents and magnetic fields formed around a shock wave.

Scientists including Bob Bingham and Alex Robinson at the Central Laser Facility at STFC’s Rutherford Appleton laboratory took these results and compared them to existing planetary data.

Using computational resources from STFC’s e-science department, they scaled them through 22 orders-of-magnitude.

They found that their measurements closely matched theories which predict that tiny magnetic fields - ‘magnetic seeds’ – precede the formation of galaxies.

These fields can be amplified by turbulent motions and can strongly affect the evolution of the galactic medium.

Professor Bingham said: “The advantage of using lasers to simulate the early processes in the formation of magnetic fields is that you can create, with a burst of laser light just a billionth of a second long, an effect that in space would take years to develop on an incomprehensible scale”.

Dr Gianluca Gregori from Oxford University, who led the work said: “Our experiment recreates what was happening in the early Universe and shows how galactic magnetic fields might have first appeared.

It opens up the exciting prospect that we will be able to explore the physics of the cosmos, stretching back billions of years, in a laser laboratory here on Earth”.

The experiments were conducted at the Laboratoire pour l’Utilisation de Lasers Intenses laser facility in France.

For further details see the Oxford University press release

CANADA Lego Man in Space - YouTube

A video posted on YouTube shows the amazing voyage of a Lego man sent into space on a homemade spacecraft by two Toronto students.

Mathew Ho and Asad Muhammad, both 17, used a weather balloon ordered online and a makeshift Styrofoam spacecraft to send the plastic astronaut 15 miles into the stratosphere, reports said.

Their high school principal Lecourgos Papathanasakis confirmed the "amazing voyage" but neither of the teens was immediately available for comment.

The accelerated video clip shows highlights of the Lego man during his 97-minute odyssey.

Ultimately, he is seen holding a Canadian flag with the curvature of the Earth and the blackness of space in the background.

Canadian media said the pair had fitted a box tethered to the balloon with four cameras and a cellphone enabled with a GPS (global positioning system) device to capture the journey.

They then added a home-made nylon parachute, using Asad's mother's sewing machine, so the Lego man would return to Earth safely.

The balloon was filled with helium purchased from a party supply store.

The whole enterprise cost less than £320.

The duo then consulted a website to calculate the estimated landing spot of the weather balloon based on launch coordinates, prevailing winds and other data before launching it from a soccer pitch in nearby Newmarket, Ontario.

At four miles in altitude, the balloon travelled out of cell phone range and the GPS signal also cut out, so they went home and waited until Ho's iPad beeped.

The Lego man had called home. It had re-entered the atmosphere, picked up the cell signal again and touched down in a field 75 miles from the launch point.

Michael Reid, an astrophysicist at the University of Toronto, said what Ho and Muhammad were able to achieve is extraordinary.

"There are people that are doing it, but I haven't seen many examples of 17-year-old kids doing it," Reid said. "It's a pretty impressive accomplishment."

Tuesday, January 24, 2012

Rice lab mimics Jupiter's Trojan asteroids inside a single atom - YouTube

Rice University physicists have built an accurate model of part of the solar system inside a single atom.

In a new paper in Physical Review Letters, Rice's team and collaborators from Oak Ridge National Laboratory and the Vienna University of Technology showed they could make an electron orbit the atomic nucleus in the same way that Jupiter's Trojan asteroids orbit the sun.

The findings uphold a 1920 prediction by physicist Niels Bohr.

"Bohr predicted that quantum mechanical descriptions of the physical world would, for systems of sufficient size, match the classical descriptions provided by Newtonian mechanics," said lead researcher Barry Dunning, Rice's Sam and Helen Worden Professor of Physics and chair of the Department of Physics and Astronomy.

"Bohr also described the conditions under which this correspondence could be observed. In particular, he said it should be seen in atoms with very high principal quantum numbers, which are exactly what we study in our laboratory."

Bohr was a pioneer of . His 1913 atomic model, which is still widely invoked today, postulated a small nucleus surrounded by electrons moving in well-defined orbits and shells.

The word "quantum" in quantum mechanics derives from the fact that these orbits can have only certain well-defined energies.

Jumps between these orbits lead to absorption or emission of specific amounts of energy termed quanta.

As an electron gains energy, its quantum number increases, and it jumps to higher orbits that circle ever farther from the nucleus.

In the new experiments, Rice graduate students Brendan Wyker and Shuzhen Ye began by using an to create a Rydberg atom.

Rydberg atoms contain a highly excited electron with a very large quantum number. In the Rice experiments, potassium atoms with quantum numbers between 300 and 600 were studied.

NASA MODIS Image: Winter Storm in the Pacific Northwest

The image is a false-colour scene that better distinguishes between snow and clouds. The Ice and snow appear red.

A severe winter storm pummeled the Pacific Northwest in January late 2012, icing roads, downing power lines, and prompting avalanche warnings.

On January 20, more than 250,000 customers were without electricity, as utility crews struggled to restore power, news sources said.

Rising temperatures and potential new rainfall raised the possibility of flooding in the days that followed.

Snow still blanketed much of Washington state on January 23, 2012, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured these images.

Liquid-water clouds are white, and ice clouds are peach. Vegetation is bright green.

Snow blankets the region east of Seattle and Portland, stretching all the way to the Idaho border. In the band of forest along the Pacific Coast, snow may be more prevalent than it appears, as it is sometimes hidden from satellite imagers by trees.

Warmer air blew into the region soon after the storm, adding to hazardous conditions. Flooding closed roads and forced some residents into emergency shelters.

On January 23, KVAL reported that a fresh storm was approaching the region and might drop several inches of rain.

The National Weather Service issued a flood warning for the Portland area, as the new round of rain had the potential to push rivers into flood stage.