Sunday, November 30, 2014

Invisible shield to ultrarelativistic electrons found thousands of miles above Earth

Scientists have discovered an invisible shield roughly 7,200 miles above Earth. 

Image courtesy Andy Kale, University of Alberta.

A team led by the University of Colorado Boulder has discovered an invisible shield some 7,200 miles above Earth that blocks so-called "killer electrons," which whip around the planet at near-light speed and have been known to threaten astronauts, fry satellites and degrade space systems during intense solar storms.

The barrier to the particle motion was discovered in the Van Allen radiation belts, two doughnut-shaped rings above Earth that are filled with high-energy electrons and protons, said Distinguished Professor Daniel Baker, director of CU-Boulder's Laboratory for Atmospheric and Space Physics (LASP).

Held in place by Earth's magnetic field, the Van Allen radiation belts periodically swell and shrink in response to incoming energy disturbances from the sun.

As the first significant discovery of the space age, the Van Allen radiation belts were detected in 1958 by Professor James Van Allen and his team at the University of Iowa and were found to be comprised of an inner and outer belt extending up to 25,000 miles above Earth's surface.

In 2013, Baker, who received his doctorate under Van Allen, led a team that used the twin Van Allen Probes launched by NASA in 2012 to discover a third, transient "storage ring" between the inner and outer Van Allen radiation belts that seems to come and go with the intensity of space weather.

The latest mystery revolves around an "extremely sharp" boundary at the inner edge of the outer belt at roughly 7,200 miles in altitude that appears to block the ultrafast electrons from breeching the shield and moving deeper towards Earth's atmosphere.

"It's almost like theses electrons are running into a glass wall in space," said Baker, the study's lead author.

"Somewhat like the shields created by force fields on Star Trek that were used to repel alien weapons, we are seeing an invisible shield blocking these electrons. It's an extremely puzzling phenomenon."

A paper on the subject was published in Nature 'An impenetrable barrier to ultrarelativistic electrons in the Van Allen radiation belts.'

The team originally thought the highly charged electrons, which are looping around Earth at more than 100,000 miles per second, would slowly drift downward into the upper atmosphere and gradually be wiped out by interactions with air molecules, but the impenetrable barrier seen by the twin Van Allen Probes stops the electrons before they get that far, said Baker.

The group looked at a number of scenarios that could create and maintain such a barrier.

"Nature abhors strong gradients and generally finds ways to smooth them out, so we would expect some of the relativistic electrons to move inward and some outward," said Baker.

"It's not obvious how the slow, gradual processes that should be involved in motion of these particles can conspire to create such a sharp, persistent boundary at this location in space."

Another scenario is that the giant cloud of cold, electrically charged gas called the plasmasphere, which begins about 600 miles above Earth and stretches thousands of miles into the outer Van Allen belt, is scattering the electrons at the boundary with low frequency, electromagnetic waves that create a plasmapheric "hiss," said Baker.

The hiss sounds like white noise when played over a speaker, he said.

"I think the key here is to keep observing the region in exquisite detail, which we can do because of the powerful instruments on the Van Allen probes."

"If the sun really blasts the Earth's magnetosphere with a coronal mass ejection (CME), I suspect it will breach the shield for a period of time," said Baker, also a faculty member in the astrophysical and planetary sciences department.

"It's like looking at the phenomenon with new eyes, with a new set of instrumentation, which give us the detail to say, 'Yes, there is this hard, fast boundary,'" said John Foster, associate director of MIT's Haystack Observatory and a study co-author.

NGC 2074: The Seahorse of the Large Magellanic Cloud

The Seahorse of the Large Magellanic Cloud 

Image Credit: NASA, ESA, and M. Livio (STScI)

Explanation: It may look like a grazing seahorse, but the dark object toward the image right is actually a pillar of smoky dust about 20 light years long.

The curiously-shaped dust structure occurs in our neighboring Large Magellanic Cloud, in a star forming region very near the expansive Tarantula Nebula.

The energetic nebula is creating a star cluster, NGC 2074, whose center is visible just off the top of the image in the direction of the neck of the seahorse.

The representative color image was taken in 2008 by the Hubble Space Telescope's Wide Field Planetary Camera 2 in honour of Hubble's 100,000th trip around the Earth.

As young stars in the cluster form, their light and winds will slowly erode the dust pillars away over the next million years.

The Sylacauga meteorite: Mrs Hodges Struck and wounded

This image shows Ms Ann Hodges in hospital and clearly shows the severe bruising caused by the meteorite.

NB: An impact crater is called an "astrobleme."

Credit: Jay Leviton, Time & Life Pictures / Getty Images

60 years ago today, at 2:46 p.m. local time, a meteor burned over Sylacauga, Alabama.

Normally, this wouldn't be news, except that this fragment of interplanetary debris was pretty big, probably massing dozens of kilograms.

It broke up high over the ground, creating a fireball bright enough to be witnessed across three states.

Most of it became vapour and very small chunks, but one piece, with a mass of 3.9 kilos (8.5 pounds), survived its atmospheric entry.

Falling at terminal velocity, a couple of hundred kilometers per hour, it made it all the way to the ground.

Kinda, there were two things in its way: A house, and Ms Ann Hodges.

The rock (Sylacauga meteorite) slammed into the house, punching a hole in the roof.

Still moving rapidly, it hit a radio (at the time, a pretty large piece of furniture), careered off, and smacked into the hand and hip of Ms. Ann Hodges, who was napping on the couch nearby.

It left a fierce bruise on her side that. This event is the most well-documented case of a human hit by a meteorite in history.

Some believe the real story happened after Hodges was hit. There are some fairly complete articles about the aftermath at the Encyclopedia of Alabama and the Decatur Daily.

Basically, there was a big tussle over who owned the meteorite. Hodges and her husband were renting the house from one Birdie (or Bertie) Guy.

This picture shows the hole in the ceiling and the meteorite fragment held in the policeman's hand.

Mrs Hodges is standing next to the policeman.

Credit: Jay Leviton, Time & Life Pictures / Getty Images

Legally, Guy owned the meteorite, since it landed on her property, but public opinion, unsurprisingly, sided with Hodges to keep it.

The legal wrestling went on for some time until Guy gave up the lawsuit, but by that time interest had waned, and no one wanted to buy the rock.

Hodges initially used it as a doorstop but eventually she donated it to the Alabama Museum of Natural History, where it’s still on display in the Smith Hall, alongside the State Fossil of Alabama: Basilosaurus cetoides.

A Tenham Meteorite Sheds Light on Bridgmanite, a Mysterious Mineral

A thin section of a Tenham meteorite reveals a vein of bridgmanite.

Credit: Tschauner et al., 2014, Science/AAAS

The Tenham meteoritea rock from space, is giving scientists the first glimpse of a mineral long thought to be the most abundant mineral on Earth, but which researchers lacked a natural sample of until now.

This discovery could shed light on the structure and dynamics of the inner Earth, as well as the early history of the solar system, according to the new paper.

"The search for this mineral in meteorites has been going on for decades, it was just a matter of finding the right method for detecting it," said lead study author Oliver Tschauner, a mineralogist at the University of Nevada, Las Vegas.

The mineral is a high-density version of magnesium iron silicate. It is the most abundant mineral on Earth, and makes up about 38 percent of the planet's volume, but it's only stable at very high pressures and temperatures, so for decades, researchers had only seen lab-generated versions of it.

Under the heat and pressure found in Earth's lower mantle, which extends from about 410 to 1,615 miles (660 to 2,600 kilometers) below the planet's surface, magnesium silicate can form what is called a perovskite structure, which can be imagined as an array of double pyramids that are joined at their corners.

The centers of each pyramid are made of silicon, the apexes and corners are made of oxygen, and magnesium and iron reside in the spaces between each double pyramid.

But scientists had not discovered a naturally occurring version of this mineral until now, the mineral would not survive the long journey from the lower mantle to Earth's surface because it would readily transform into lower-density minerals.

The fact that scientists had not found any specimens of magnesium iron silicate perovskite in nature also meant it could not get an official mineral name from the International Mineralogical Association (IMA).

This presented geologists with the odd situation of a nameless mineral being the most abundant one on Earth.

Since researchers could not find a naturally occurring version of magnesium iron silicate perovskite from Earth, they instead looked to space.

They hypothesized that high-speed cosmic impacts could generate the pressures and temperatures needed to create this mineral, and samples of it could then come to Earth as meteorites knocked off their parent asteroids or planets.

Recently, Tschauner and his colleagues carefully isolated magnesium iron silicate perovskite in a Tenham meteorite.

The mineral was given has the official name of "bridgmanite," after the father of high-pressure experiments, Nobel laureate Percy Bridgman, according to the report, published in the Nov. 28 issue of the journal Science.

The researchers analyzed a Tenham meteorite, a rock that was part of a meteor shower that rained down on Australia on a spring night in 1879.

This meteorite bore signs that it was part of an asteroid that experienced a great impact.

The stone also possessed minerals called akimotoite and ringwoodite, which are similar in composition and origin to bridgmanite.

Tschauner and his colleagues used high-energy X-rays from a synchrotron, a particular type of cyclic particle accelerator, descended from the cyclotron, in which the guiding magnetic field (bending the particles into a closed path) is time-dependent, being synchronized to a particle beam of increasing kinetic energy.

These intense X-rays do little damage to bridgmanite, thus helping the scientists prove its composition and crystal structure.

The researchers found that bridgmanite was higher in iron and sodium than they had expected based on synthetic samples.

"This gives interesting insights for what might be going on in the lower mantle," Tschauner said.

Tschauner added that detecting bridgmanite in other meteorites could shed light on the strength of the impacts their parent bodies experienced.

The pressures and durations of these impacts in turn "allow us to estimate the size of the parent bodies of these meteorites, and with enough data, we can, for given points in time in the solar system's history, figure out how large bodies in the solar system were," Tschauner said.

Friday, November 28, 2014

Mars, Lagoon and Trifid Nebulas Shine in Stunning Skywatcher Photos

These amazing images are of the planet Mars passing below two nebulas. 

Astrophotographer Derek Demeter took the images from the Stardust Ranch in Okeechobee, Florida. 

Credit: Derek Demeter/Seminole State College

These amazing images show the planet Mars passing below two nebulas.

Astrophotographer Derek Demeter took the images from the Stardust Ranch in Okeechobee, Florida.

Demeter is the director of the Emil Buehler Perpetual Trust Planetarium at Seminole State College of Florida.

The photos capture Mars passing below two objects known as the Lagoon and Trifid nebulas.

Both are located in the constellation Sagittarius and are found in the central region of our Milky Way galaxy.

“This is a great perspective of our solar system relative to the galaxy,” Demeter told reporters.

The image shows Mars passing below two objects known as the Lagoon and Trifid nebulas. 

Astrophotographer Derek Demeter took the images from the Stardust Ranch in Okeechobee, Florida. 

Credit: Derek Demeter/Seminole State College

Located about 5,000 light-years from Earth, the Lagoon Nebula is one of two star-forming regions visible to the unaided eye from the Northern Hemisphere.

It is about 110 light-years across and is also known as Messier 8 or NGC 6523. The Trifid Nebula (Messier 20 or NGC 6514) is a combination of an emission nebula (the red area), a reflection nebula (the blue area) and a dark nebula.

Also visible are the star-forming regions of NGC 6559, IC 1274 and IC 1275.

Neutron Stars: Ripples in Space-Time Could Reveal 'Strange Stars' - video

By looking for ripples in the fabric of space-time, scientists could soon detect "strange stars," objects made of stuff radically different from the particles that make up ordinary matter, researchers say.

The protons and neutrons that make up the nuclei of atoms are made of more basic particles known as quarks.

There are six types, or "flavours," of quarks: up, down, top, bottom, charm and strange. Each proton or neutron is made of three quarks: Each proton is composed of two up quarks and one down quark, and each neutron is made of two down quarks and one up quark.

In theory, matter can be made with other flavours of quarks as well. Since the 1970s, scientists have suggested that particles of "strange matter" known as strangelets, made of equal numbers of up, down and strange quarks, could exist.

In principle, strange matter should be heavier and more stable than normal matter, and might even be capable of converting ordinary matter it comes in contact with into strange matter.

Scene from a NASA animation showing two neutron stars colliding.

Credit: NASA's Goddard Space Flight Center

However, lab experiments have not yet created any strange matter, so its existence remains uncertain.

One place strange matter could naturally be created is inside neutron stars, the remnants of stars that died in catastrophic explosions known as supernovas.

Neutron stars are typically small, with diameters of about 12 miles (19 kilometers) or so, but are so dense that they weigh as much as the sun.

A chunk of a neutron star the size of a sugar cube can weigh as much as 100 million tons.

Under the extraordinary force of this extreme weight, some of the up and down quarks that make up neutron stars could get converted into strange quarks, leading to strange stars made of strange matter, researchers say.

A strange star that occasionally spurts out strange matter could quickly convert a neutron star orbiting it in a binary system into a strange star as well.

Prior research suggests that a neutron star that receives a seed of strange matter from a companion strange star could transition to a strange star in just 1 millisecond to 1 second.

The researchers suggest that events involving strange stars could explain two short gamma-ray bursts, giant explosions lasting less than 2 seconds, seen in deep space in 2005 and 2007.

The Laser Interferometer Gravitational-Wave Observatory (LIGO) did not detect gravitational waves from either of these events, dubbed GRB 051103 and GRB 070201.

Future research could detect strange-star events. Using the Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO), whose first observing run is scheduled for 2015, the researchers expect to detect about 0.13 mergers per year of neutron stars with strange stars, or about one such merger every eight years.

Using the Einstein Telescope currently being designed in the European Union, the scientists eventually expect to detect about 700 such events per year, or about two per day.

Rising Sea Levels Show Strange Patterns and Trends

The world’s oceans are connected, but they rise at different rates.  Philip R. Thompson and Mark A. Merrifield

The oceans aren’t level. Over the span of decades, atmospheric weather patterns push water the water around, causing sea levels in connected basins to rise and fall somewhat predictably.

However, since 2000 the two huge basins in the southern hemisphere have broken their trend, rising jointly over 2 millimeters per year.

A new paper in Geophysical Research Letters proposes that this new development, found using satellite-derived sea height data, could be due to changes in a large climate system that wraps around the entire southern hemisphere.

The map above shows the different oceanic basins (which aren’t always separated by continental bodies).

The Indian ocean and southern Atlantic form the largest such connected system, and historically a rise in one would result in the fall of another.

In the bottom graph, the south Atlantic and Indian Ocean break their pattern of rising and falling. 

Credit: Philip R. Thompson andMark A. Merrifield

The graph to the left shows the relationships between sea level height for four pairs of connected ocean basins.

In the top three systems, the thin lines show how historically, when one basin rises, the other falls, and vice versa.

However, in the bottommost graph, showing the south Atlantic and Indian oceans, these trends break in the late 1990s, and both oceans rise in tandem.

The thick lines at the bottom of each graph show how a different weather pattern dominates how the water is redistributed between connected basins.

Changes in the east to west wind pattern seem to be driving the difference in Indian/southern Atlantic system.

The scientists have several hypotheses for what’s driving the shift in wind patterns, all of which are linked to climate change.

ESA: Eutelsat-9B satellite with its EDRS-A payload

The Eutelsat-9B satellite with its EDRS-A payload is shown in the anechoic test chamber of Airbus Defence and Space (EADS) in Toulouse, France. It completed its final antenna pattern tests today.

EDRS-A is a hosted package as the first of two nodes of the European Data Relay System set to be launched next year.

Also known as Europe’s SpaceDataHighway, EDRS will use cutting-edge laser technology to capture and relay information gathered by Earth-observing satellites.

By travelling via EDRS’s high-speed links and stationary position over Europe, the satellites’ data reach the ground in near-real time.

While EDRS-A’s Laser Communication Terminal is being checked for flight, the terminals on Copernicus’ Sentinel-1A and Alphasat telecom satellite are already fully operational in space, ready to demonstrate their ground-breaking capabilities for multi-gigabit optical communications in space.

On Friday, 28 November the first Earth observation image gathered by Sentinel-1A and relayed to a ground station at the DLR German Aerospace Center in Oberpfaffenhofen,

Germany, via Alphasat will be presented at an event at ESA’s European Space Operations Centre in Darmstadt, Germany.

Thursday, November 27, 2014

Process converts human waste into rocket fuel

At NASA's request, University of Florida researchers have figured out how to turn human waste into rocket fuel.

Adolescent jokes aside, the process finally makes useful something that until now has been collected to burn up on re-entry.

What's more, like so many other things developed for the space program, the process could well turn up on Earth, said Pratap Pullammanappallil, a UF associate professor of agricultural and biological engineering.

"It could be used on campus or around town, or anywhere, to convert waste into fuel," Pullammanappallil said.

In 2006, NASA began making plans to build an inhabited facility on the moon's surface between 2019 and 2024.

As part of NASA's moon-base goal, the agency wanted to reduce the weight of spacecraft leaving Earth.

Historically, waste generated during spaceflight would not be used further.

NASA stores it in containers until it's loaded into space cargo vehicles that burn as they pass back through the Earth's atmosphere.

For future long-term missions, though, it would be impractical to bring all the stored waste back to Earth.

Dumping it on the moon's surface is not an option, so the space agency entered into an agreement with UF to develop test ideas.

Abhishek Dhoble
Pullammanappallil and then-graduate student Abhishek Dhoble accepted the challenge.

"We were trying to find out how much methane can be produced from uneaten food, food packaging and human waste," said Pullammanappallil, a UF Institute of Food and Agricultural Sciences faculty member and Dhoble's adviser.

"The idea was to see whether we could make enough fuel to launch rockets and not carry all the fuel and its weight from Earth for the return journey."

"Methane can be used to fuel the rockets. Enough methane can be produced to come back from the moon."

NASA started by supplying the UF scientists with a packaged form of chemically produced human waste that also included simulated food waste, towels, wash cloths, clothing and packaging materials, Pullammanappallil said.

He and Dhoble, now a doctoral student at the University of Illinois, ran laboratory tests to find out how much methane could be produced from the waste and how quickly.

They found the process could produce 290 liters of methane per crew per day, all produced in a week, Pullammanappallil said.

A typical Anaerobic Digestor process using farmyard waste as a source of fuel.

Their results led to the creation of an anaerobic digester process, which kills pathogens from human waste, and produces biogas, a mixture of methane and carbon dioxide by breaking down organic matter in waste.

In earth-bound applications, that fuel could be used for heating, electricity generation or transportation.

The digestion process also would produce about 200 gallons of non-potable water annually from all the waste.

That is water held within the organic matter, which is released as organic matter decomposes.

Through electrolysis, the water can then be split into hydrogen and oxygen, and the astronauts can breathe oxygen as a back-up system.

The exhaled carbon dioxide and hydrogen can be converted to methane and water in the process, he said.

ESA JUICE: Mission gets go ahead towards exploration of Jupiter

Artist's impression of the JUICE mission. 

Credit: ESA/AOES

The European Space Agency's JUICE (JUpiter ICy moons Explorer) mission has been given the green light to proceed to the next stage of development.

This approval is a milestone for the mission, which aims to launch in 2022 to explore Jupiter and its potentially habitable icy moons.

JUICE gained approval for its implementation phase from ESA’s Science Programme Committee during a meeting at the European Space Astronomy Centre near Madrid, Spain, on 19 and 20 November 2014.

Chosen by ESA in May 2012 to be the first large mission within the Cosmic Vision Programme JUICE is planned to be launched in 2022 and to reach Jupiter in 2030.

The mission will tour the giant planet to explore its atmosphere, magnetosphere and tenuous set of rings and will characterise the icy moons Ganymede, Europa and Callisto.

Detailed investigations of Ganymede will be performed when JUICE enters into orbit around it, the first time any icy moon has been orbited by a spacecraft.

During its lifetime, the mission will give us an unrivalled and in-depth understanding of the Jovian system and of these moons.

The scientific goals of the mission are enabled by its instrument suite. This includes cameras, spectrometers, a radar, an altimeter, radio science experiments and sensors used to monitor the plasma environment in the Jovian system.

In February 2013, the SPC approved the payload that will be developed by scientific teams from 16 European countries, the USA and Japan, through corresponding national funding.

At the November 2014 meeting of the SPC, the multilateral agreement for JUICE was also approved.

This agreement provides the legal framework for provision of payload equipment and ongoing mission support between funding agencies.

Planet Labs are Using Tiny Satellites to Benefit Humanity - Video

A small group of scientists from Planet Labs monitor the Earth's resources using a network of tiny satellites that they call “Doves.”

In January 2014, they delivered Flock 1, the world’s largest constellation of Earth-imaging satellites, made up of 28 Doves.

Together with subsequent launches, they have launched 71 Doves, toward imaging the entire Earth, every day.

Planet creates commercial and humanitarian value with the market's most capable global imaging network.

Fresh data from any place on Earth is foundational to solving commercial, environmental, and humanitarian challenges.

Their global sensing and analytics platform unlocks the ability to understand and respond to change at a local and global scale.

Beautifully illustrated poems celebrating Space and Science - Joanna Tilsley

“The ideal scientist thinks like a poet and works like a bookkeeper,” the influential biologist E.O. Wilson said in his spectacular recent conversation with the former Poet Laureate Robert Hass, exploring the shared creative wellspring of poetry and science.

A beautiful embodiment of it comes from 30 Days, an unusual and bewitching series of “quantum poetry” by xYz, the pseudonym of British biologist and poet Joanna Tilsley, who began writing poetry at the age of eight and continued, for her own pleasure, until she graduated college with a degree in biology.

In April of 2013, while undergoing an emotional breakdown, Tilsley took a friend up on a dare and decided to participate in NaPoWriMo, an annual creative writing project inviting participants to write a poem a day for a month.

Immersed in cosmology and quantum physics at the time, she found herself enchanted by the scientific poetics of nature as she strolled around her home in North London.

Translating that enchantment in lyrical form, she produced a series of thirty poems on everything from DNA to the exoplanet Keppler-62F, a “super-Earth-sized planet orbiting a star smaller and cooler than the sun,” to holometabolism, the process by which the caterpillar metamorphoses into a butterfly, to the Soviet cosmonaut Yuri Gagarin, the first human being to see Earth from space.

 I had been reading a lot about cosmology and new physics at the time, and as I took my habitual walks across the marshes surrounding my home in North London, I pondered deeply upon the dimensions of space and time through which I was passing, as well as existing euphorically in the moment with the first stirrings of spring. 

The poems followed naturally through; in fact they burst out of me, allowing me to weave a pattern of deep emotion through a weft of scientific fact.

Wednesday, November 26, 2014

How NASA Censored Astronauts Swearing

During the early days of the space race the public relations handlers at NASA had an image to uphold.

America's astronauts were the new face of a nation: they were the bold, brave explorers of the beyond. But this image didn't always align with the more rough-and-tumble types who got the job.

Barring a couple of scientists, almost all of Americas early astronauts had moved over from the military.

Many having been experimental aircraft test pilots, a job not exactly known for its dependence on decorum.

As space history writer Amy Shira Teitel notes, some astronauts had trouble maintaining family-friendly language, and NASA went to sometimes great lengths to keep that fact under wraps.

In some cases, as Teitel covers in her Vintage Space video series, sometimes this censorship amounted to little more than scrubbing down transcripts, replacing “farts” with “gas” and cutting a few f-bombs. (Caution: the video contains cussing.)

In other cases, however, NASA took great pains to clean up astronauts' language. A few years ago Teitel wrote about the space agency's trick to harness one unnamed astronaut's filthy mouth:

One [astronaut] in particular had the unfortunate habit of filling space with profanities, when his mind wandered.  
This posed a problem for NASA - with the world watching astronauts walking around the lunar surface, how could the organization be sure the his transmissions from the Moon would be family-friendly? 
In preparing for his mission, NASA had the astronaut hypnotized. Rather than curse, a psychiatrist put the idea in his head that he would rather hum when his mind wandered.  
The hypnotized astronaut is rarely named, but only one man can be heard humming as he skipps across the lunar surface.  
Transmissions from Commander Pete Conrad are punctuated with "dum de dum dum dum" and "dum do do do, do do" making him the likliest candidate.

Even today astronauts maintain a largely squeaky clean image (best personified, perhaps, by former Canadian astronaut Chris Hadfield's endearingly non-threatening mustache). But just as before, what we see on the surface isn't all there is, the inner lives of astronauts in orbit are filled with frustrations and annoyances, and, probably, a few interlaced swears.

JAXA Ready to Face New Challenges - Hayabusa2

It has been four years since the Hayabusa’s dramatic return from space,bringing back the world’s first samples from an asteroid.

To further clarify the mystery of the origin and evolution of human beings, the Hayabusa2 is leaving for space.

This video explains the special features and significance of the Hayabusa2 mission in an easy and simple manner.

NASA's Van Allen Probes Detects an Impenetrable Barrier in Space

Two donuts of seething radiation that surround Earth, called the Van Allen radiation belts, have been found to contain a nearly impenetrable barrier that prevents the fastest, most energetic electrons from reaching Earth.

A cloud of cold, charged gas around Earth, called the plasmasphere and seen here in purple, interacts with the particles in Earth's radiation belts, shown in grey, to create an impenetrable barrier that blocks the fastest electrons from moving in closer to our planet.

Image Credit: NASA/Goddard

The Van Allen belts are a collection of charged particles, gathered in place by Earth’s magnetic field. They can wax and wane in response to incoming energy from the sun, sometimes swelling up enough to expose satellites in low-Earth orbit to damaging radiation.

The discovery of the drain that acts as a barrier within the belts was made using NASA's Van Allen Probes, launched in August 2012 to study the region.

A paper on these results appeared in the Nov. 27, 2014, issue of Nature magazine.

“This barrier for the ultra-fast electrons is a remarkable feature of the belts," said Dan Baker, a space scientist at the University of Colorado in Boulder and first author of the paper.

"We're able to study it for the first time, because we never had such accurate measurements of these high-energy electrons before."

Understanding what gives the radiation belts their shape and what can affect the way they swell or shrink helps scientists predict the onset of those changes. Such predictions can help scientists protect satellites in the area from the radiation.

Visualization of the radiation belts with confined charged particles (blue & yellow) and plasmapause boundary (blue-green surface)

The Van Allen belts were the first discovery of the space age, measured with the launch of a US satellite, Explorer 1, in 1958.

In the decades since, scientists have learned that the size of the two belts can change, or merge, or even separate into three belts occasionally.

But generally the inner belt stretches from 400 to 6,000 miles above Earth's surface and the outer belt stretches from 8,400 to 36,000 miles above Earth's surface.

A slot of fairly empty space typically separates the belts. But, what keeps them separate? Why is there a region in between the belts with no electrons?

Enter the newly discovered barrier. The Van Allen Probes data show that the inner edge of the outer belt is, in fact, highly pronounced. For the fastest, highest-energy electrons, this edge is a sharp boundary that, under normal circumstances, the electrons simply cannot penetrate.

"When you look at really energetic electrons, they can only come to within a certain distance from Earth," said Shri Kanekal, the deputy mission scientist for the Van Allen Probes at NASA's Goddard Space Flight Center in Greenbelt, Maryland and a co-author on the Nature paper. "This is completely new. We certainly didn't expect that."

The team looked at possible causes. They determined that human-generated transmissions were not the cause of the barrier. They also looked at physical causes.

Could the very shape of the magnetic field surrounding Earth cause the boundary? Scientists studied but eliminated that possibility. What about the presence of other space particles? This appears to be a more likely cause.

The radiation belts are not the only particle structures surrounding Earth. A giant cloud of relatively cool, charged particles called the plasmasphere fills the outermost region of Earth's atmosphere, beginning at about 600 miles up and extending partially into the outer Van Allen belt.

The particles at the outer boundary of the plasmasphere cause particles in the outer radiation belt to scatter, removing them from the belt.

Proton Rocket Technical Issues Postpone ILS Launch of Astra 2G

Industry officials said the delay of the launch of Astra 2G is likely to push the launch into mid-December at the earliest. 

Credit: ILS photo

The planned Nov. 28 launch of a Russian Proton rocket carrying the commercial Astra 2G telecommunications satellite has been scrubbed following communications issues with the rocket’s Breeze-M upper stage, industry officials and the Russian space agency, Roscosmos, said Nov. 26.

The rocket will be removed from the launch pad, its upper stage taken off and the Astra 2G will be removed for safekeeping pending inspection of the Breeze-M. It was not immediately clear whether another Breeze-M was available at the Russian-run Baikonur Cosmodrome launch complex in Kazakhstan.

Industry officials said the delay is likely to push the launch into mid-December at the earliest.

Roscosmos said a Russian State Commission decided to halt the launch following unspecified command-and-control anomalies on Breeze-M.

Yves Feltes, spokesman for Luxembourg-based SES, said the Astra 2G satellite, built by Airbus Defence and Space, is in good health and that the company would await the conclusions of the tests on Breeze-M before announcing a new launch date.

“We are in control of the situation with respect to Astra 2G,” Feltes said. “Astra 2G is safe and there are no issues with it. It will be removed from the rocket for additional checks on Breeze-M because the Breeze-M did not correctly respond to commands sent to it while the rocket was on the launch pad.”

The delay is the latest in a series of problems affecting Russia’s heavy-lift Proton rocket in recent years, which have pushed up the cost of insurance premiums and given its commercial competitor, Arianespace of Europe, room to raise its prices for heavier communications satellites.

International Launch Services of Reston, Virginia, which is owned by Proton prime contractor Khrunichev Space Center of Moscow and is in charge of selling commercial Proton launches, was not immediately available for comment on the launch scrub.

ILS in recent weeks has been battling widespread industry opinion that the Oct. 22 Proton launch of a Russian telecommunication satellite — a launch not handled by ILS but rather as part of Russia’s Federal space program — featured an underperformance by Breeze-M.

That satellite, the Express-AM6 owned by Russian Satellite Communications Co. (RSCC) of Moscow, will take longer than expected to reach its final operating orbit but is otherwise healthy.

SES and its insurers had raised questions about the Oct. 22 launch but ultimately were reassured that, whatever the issues were, they had been resolved, industry officials said. Plans for the Nov. 28 launch were permitted to proceed.

Rapid Coordination Extends Space‐Based Sun‐Climate Record

Total solar irradiance (TSI), a measure of how much solar radiative energy hits the entirety of Earth, is the principle energy input to the global climate system.

Collecting accurate TSI data spanning multiple years helps scientists understand how much solar radiation is deposited in the atmosphere and at the surface and thus how much energy is available to influence weather, climate, the cryosphere, atmosphere dynamics, and ocean currents.

Because of TSI’s relevance for natural climate change, TSI has been identified within the US president’s National Plan for Civil Earth Observations [ Holdren, 2014 ] as a vital observation for determining the Earth’s net energy balance.

Similarly, within the National Oceanic and Atmospheric Administration (NOAA) Climate Data Record program, TSI is recognized as an important long‐term measurement for a robust, sustainable, and scientifically defensible approach to climate change

Unfortunately, the main contributors to the TSI record have terminated their observations or are suffering degraded performance.

These include the NASA Active Cavity Radiometer Irradiance Monitor Satellite (ACRIMSat), whose mission ended in December 2013 due to battery problems after nearly 14 years in orbit; the Swiss Precision Monitor Sensor (PREMOS) instrument aboard the French Picard satellite, whose mission ended in March 2014; and the Variability of Solar Irradiance and Gravity Oscillations (VIRGO) aboard the European Space Agency/NASA Solar and Heliospheric Observatory (SOHO), which is still operational, albeit with degraded performance, after 18 years in orbit.

To ensure the longevity of the TSI record without data gaps, scientists had to work fast.

Extraordinary teamwork between NASA, the Laboratory for Atmospheric and Space Physics at the University of Colorado (CU‐LASP), NOAA, and the Air Force over the last few years has enabled the extension of TSI measurements.

This cooperation has included revitalizing the Solar Radiation and Climate Experiment (SORCE, see Image ), an aging NASA satellite launched in 2003; the launch and initial operations of the TSI Calibration Transfer Experiment (TCTE), a NOAA/NASA irradiance instrument aboard an Air Force satellite; and identifying a new opportunity for deployment on the International Space Station (ISS) in 2017 of the NOAA Total and Spectral Solar Irradiance Sensor (TSIS).

Read the full report here

European Service Module for NASA's Orion new Crewed Spacecraft

On 17 November, ESA signed a contract in Berlin with the Airbus Defence and Space division to develop and build the European Service Module for Orion, NASA’s new crewed spacecraft. 

It is the first time that Europe will provide system-critical elements for an American space transportation vehicle.

NASA intends to use this service module for the 2017 unmanned flight of Orion. The vehicle will perform a high-altitude orbital mission around the Moon.

This flight will be a precursor for future Orion human space exploration missions beyond low-Earth orbit.

The official name of Orion is ‘Multi-Purpose Crew Vehicle’, because the spacecraft can be used to conduct different missions. Eventually, NASA will use Orion to send astronauts to Mars.

NASA’s Orion spacecraft will carry astronauts further into space than ever before using a module based on Europe’s Automated Transfer Vehicles (ATV). 

ATV’s distinctive four-wing solar array is recognisable in this concept. 

The ATV-derived service module, sitting directly below Orion’s crew capsule, will provide propulsion, power, thermal control, as well as supplying water and gas to the astronauts in the habitable module. 

The first Orion mission will be an uncrewed lunar flyby in 2017, returning to Earth’s atmosphere at 11 km/s ­– the fastest reentry ever.

Credit: ESA

The design of the European Service Module (ESM) is based on the Automated Transfer Vehicle (ATV), the European supply craft for the International Space Station. It is a major achievement, as this is the first European development of a human spacecraft operating beyond Earth orbit.

“Being selected by NASA to develop critical elements for the Orion project – currently their most important exploration project – is a clear recognition of Europe’s performance in the frame of the ATV programme,” says Nico Dettmann, Head of ESA’s Space Transportation Department.

“Cooperation with NASA is going well. It is fruitful and is happening with the same good spirit as with the International Space Station partnership,” he adds.

The ESM is a cylindrical module with a diameter of 4.5 metres and a total length – main engine excluded – of 2.7 metres. It is fitted with four solar array ‘wings’ with a span of 18.8 metres. Its dry mass is 3.5 metric tons and it can carry 8.6 tons of propellant. Besides propulsion and power, ESM carries consumables.

The Critical Design Review (CDR) is planned for 2015.

ESA GOCE: Monitoring Ocean currents

The ocean currents and their speeds (in cm/s) derived from ESA's GOCE data. 

During the mission’s final year, its super-low orbit was lowered even further to obtain improved measurements of Earth’s gravity field, from which information on ocean currents was derived. 

Buoys floating in the oceans were used to validate the above map, proving that this GOCE-based model is more accurate than any other model based on space-based data to date. 

Credit: ESA

The mean dynamic topography (MDT, in cm) of the world’s oceans in the highest resolution ever achieved from space-based data. 

MDT is calculated by taking the mean sea-surface height measured by satellites like Envisat, and subtracting the gravity model from GOCE

Red areas show where water levels are above the surface of the gravity model, while blue depicts areas where the water is below. From this, scientists calculated the speed of ocean currents.

A year after the satellite reentered the atmosphere, scientists using data from the GOCE satellite have made a breakthrough in our understanding of ocean currents.

The Gravity field and steady-state Ocean Circulation Explorer (GOCE), mapped variations in Earth’s gravity with unrivalled precision, resulting in the most accurate shape of the ‘geoid’ – a hypothetical global ocean at rest – ever produced.

While the mission is well known for its gravity measurements, the second mission objective as an ‘ocean circulation explorer’ has reached a milestone.

Using GOCE data, scientists have produced the most accurate model of ocean current speeds to date.

To do this, the GOCE geoid was subtracted from the mean sea-surface height measured over a 20-year period by satellites including ESA’s veteran Envisat.

In 2011, GOCE delivered a model of the 'geoid' pictured here. At the time, it was the most accurate ever produced. 

The colours in the image represent deviations in height (–100 m to +100 m) from an ideal geoid. 

The blue shades represent low values and the reds/yellows represent high values. 

Credit: ESA

The result shows the mean dynamic topography of the ocean surface, showing higher- and lower-than-average water levels. Based on this map, ocean currents and their speeds were calculated and validated using in situ buoys.

The result shows that this GOCE-based model is more accurate than any other model based on space data to date.

“The accurate estimate of ocean surface currents, as provided today by the combination of GOCE and altimetry data, is crucial for the better understanding of the ocean dynamics,” said Marie-Hélène Rio from the Institute of Atmospheric Sciences and Climate of the Italian National Research Council.

“In particular, the assimilation of this information into operational ocean monitoring and forecasting systems will provide highly valuable new insight into the present and future state of the ocean.”

This was just one of many GOCE results presented today at the opening of the 5th International GOCE User Workshop at the UNESCO Headquarters in Paris, France.

ESA astronaut Samantha Cristoforetti enjoying ISS Zero Gravity

After a textbook Russian launch and precise docking on Sunday night, ESA astronaut Samantha Cristoforetti, NASA astronaut Terry Virts and Roscosmos commander Anton Shkaplerov boarded the International Space Station.

This image taken by Terry of Samantha was Samantha’s first Tweet from space, with the comment: “Amazing being in space, better than anything I ever imagined. Saw my first sunrise from the Cupola today!”

The three astronauts have about a week to get used to floating around their new surroundings before taking on a full schedule of science and maintenance for the rest of their six-month mission.

Credit: ESA

US ISS space lab in relative darkness during 'sleep time'

The US ISS space lab in relative darkness during 'sleep time' on the space station.

This image was posted on Twitter by the new guy, NASA astronaut Terry Virts.

Credit: NASA

Supercomputer Simulation of Magnetic Field Loops on the Sun

Magnetic fields emerging from below the surface of the sun influence the solar wind, a stream of particles that blows continuously from the sun’s atmosphere through the solar system. 

Researchers at NASA and its university partners are using high-fidelity computer simulations to learn how these magnetic fields emerge, heat the sun’s outer atmosphere and produce sunspots and flares.

This visualization shows magnetic field loops in a portion of the sun, with colors representing magnetic field strength from weak (blue) to strong (red). 

The simulation was run on the Pleiades supercomputer at the NASA Advanced Supercomputing facility at NASA's Ames Research Center in Moffett Field, California. 

The knowledge gained through simulation results like this one help researchers better understand the sun, its variations, and its interactions with Earth and the solar system.

Image Credit: Robert Stein, Michigan State University; Timothy Sandstrom, NASA/Ames

NASA Mars Curiosity Rover: Mars Target Area 'Alexander Hills'

This view from the Mast Camera (Mastcam) on NASA's Curiosity Mars rover shows a swath of bedrock called "Alexander Hills," which the rover approached for close-up inspection of selected targets.

The mosaic of six Mastcam frames covers an area about 6 feet (2 meters) across.

It shows details within the workspace accessible using the rover's robotic arm from the rover's location when the view was acquired.

The component exposures were taken on Nov. 23, 2014, during the 817th Martian day, or sol, of Curiosity's work on Mars.

The colour has been approximately white-balanced to resemble how the scene would appear under daytime lighting conditions on Earth.

This annotated version shows the location of three targets selected for study, "Aztec," "Agate Hill" and "Cajon", and a 50-centimeter (20-inch) scale bar.

The location of Alexander Hills within the "Pahrump Hills" outcrop at the base of Mount Sharp is indicated on an earlier Mastcam vew

Tuesday, November 25, 2014

ESA IXV Spaceplane set for February launch

Arianespace has put the launch of its IXV spaceplane back on the schedule, announcing a February 2015 date for the flight.

The launch was recently postponed, but the organisation now says it's agreed with French space agency CNES that the Intermedia eXperimental Vehicle (IXV), will ascend to space on February 11 2015.

The IXV was delivered to the French Guiana spaceport in September, but hopes for a November 2014 launch were dashed in October when the European Space Agency (ESA) announced it would be postponed.

At that time, the ESA said it needed more time to analyse the flight trajectory of the Vega launcher that will hoist the space plane, because instead of the usual polar trajectory the launcher uses, the IXV test will head eastwards.

Since an easterly launch is “unprecedented” for Vega, the ESA said it wanted to generate more information on the performance of the launch vehicle, “should an anomaly occur after liftoff”.

Vega will carry the IXV to 320 km, after which it will rise under its own power to 420 km.

It will reach a speed of 7.5 km/second before re-entry, which the agency says is “fully representative of any mission from low orbit”.

The ultimate aim for the two-tonne IXV is to develop the technologies needed to launch cargoes to targets like the ISS in a reusable autonomous craft. Lift is generated not by wings but by the body design, with a couple of flaps controlling its flight.

The IXV will land in the Pacific Ocean, but the ESA ultimately wants to develop a craft that can land on conventional runways