Posted on by Ian O'Neill

Countdown to the Final Burn: ATV Jules Verne will Undock on September 5th

The ATV on approach to the station in April. Mission will end next month (ESA/NASA)

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The Automated Transfer Vehicle (A T V) Jules Verne will undock from the International Space Station (ISS) on September 5th to begin three weeks of autonomous flight, setting it up for a suicidal re-entry on September 29th. The ATV has been loaded with refuse and unwanted equipment from the ISS set to burn up in the Earth’s upper atmosphere marking the end of the life of Europe’s most advanced space vehicle. To record the event, both NASA and the European Space Agency will be photographing and videoing the descent…

The Russian Federal Space Agency Roscosmos announced the date for the end of the Jules Verne mission to the ISS on Thursday. This news comes after a highly successful period for the European ATV, proving the ATV can be used for extensive re-supply tasks and provide the station with a valuable re-boost and space debris avoidance options.

This first ATV, also known as “Jules Verne” (as it delivered two original manuscripts written by the 19th Century author to the station), was launched from French Guiana in South America on board an Ariane-5 heavy-lift rocket on March 5th. During this busy time for the Space Station, the ATV had to remain in a “parking orbit” for nearly a month before delivering supplies to the ISS crew on April 3th. Only when Space Shuttle Endeavour (STS-123) had undocked and landed on March 26th could the ATV approach and dock.

Since then, the ATV has proven to be a valuable addition to the station, surpassing all expectations. The ISS crew will miss Jules Verne as the roomy temporary supply vessel has provided a great area for the crew to sleep and wash, plus one of its empty tanks has been used to store 110 litres of condensation water. These extra (unexpected) uses prompted mission control to extend the life of the mission for an extra month.

But all good things come to an end and the ATV will undock on September 5th to begin its journey back to Earth as a fireball at the end of September. The ATV will be dropping up to six tonnes of unwanted equipment and waste from the station into a pre-designated area of the Pacific Ocean. But ESA and NASA will be watching, photographing and videoing Jules Verne’s final service to the ISS crew…

Source: Red Orbit

Posted on by Tammy Plotner

How Far Would You Go For Dark Skies?

Arkaroola Wilderness Sanctuary

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In the age of global light pollution, one thing both amateur and professional astronomers have in common is the need for clear, dark skies. While almost all of us are aware of the impact of light pollution when it comes to pure observing, the “light factor” plays a far more serious role when it comes to astronomical studies. But, there’s far deeper reasons for observatories to become increasingly remote.

While escaping light sources such as brightly-lit cities is mandatory for amateur astronomers and astrophotographers to enjoy their hobby, professional observatories seek some of the world’s most remote locations for other reasons. Both in studying and in astrophotography, splitting the light into its component colors – the spectra – of an object becomes important. For example, when studying a distant galaxy through spectroscopy, astronomers rely on the different lines in the spectral signature as a unique indicator of the presence of a certain chemical. Through the strengths of these lines, astronomers can then determine the chemical composition and temperature. What’s more, by noting how far to the red side of the spectrum the lines are shifted, astronomers can also determine how fast the object is moving…

And light pollution wrecks spectrographs.

Besides light pollution, other enemies of astrophotography and spectroscopy are high-flying airplanes, clouds, inclement weather and atmospheric conditions. One of the reasons the Hubble is so successful in the lack of atmosphere, and that’s the major reason why most remote observatories choose to locate on high peaks – the less atmosphere and the more stable the atmosphere, the better. In some circumstances, and for some equipment and telescopes, humidity can also be a problem. This is why remote observatories are also often located in desert regions as well. So, in a world that looks like this…

Earthlights - Credit: NASA
Earthlights - Credit: NASA

How far would you go for dark skies?

In a report done by ABC news a study has found that more than 40 per cent of Australia remains undamaged – and unpolluted – by humans. This means the “land down under” offers exciting possibilities for astronomical studies, not only from the perspective of viewing southern hemisphere skies, but doing research from a pristine location. This is why you’ll find research facilities such as the Anglo-Australian Observatory, Australia Telescope National Facility, Melbourne Observatory, Perth Observatory, Sydney Observatory, Siding Springs, Mills Cross Telescope, Paul Wild Observatory, Mount Stromlo Observatory and Southern Galactic International Telescope Facility.

Flinders Range
Flinders Range
While the Cobaw Plateau region on the north face of the Great Dividing Range has proved to be an excellent site for Southern Galactic Telescope Hosting, the next step is to expand operations into the Arkaroola Wilderness Sanctuary. Located 600km north of Adelaide and 130km east of Leigh Creek, and in the more rugged and spectacular northern Flinders Ranges, this 610sq km multi award-winning Wilderness Sanctuary, contains some of Australia’s most spectacular mountain views – and darkest, clearest skies. The Southern Galactic Observatory and International Telescope Hosting Facility, an internationally renowned astronomical observatory based in Victoria, is pleased to announce the establishment of its exclusive Site 2 location at the Arkaroola Wilderness Sanctuary in the Northern Flinders Ranges of South Australia. This new location will be run as part of the Australian operations in partnership with the Directors of the Arkaroola Wilderness Sanctuary and will enable research in the areas of optical / radio astronomy, planetary studies, and space atmospheric sciences by providing specific telescope hosting services and remote control accessability together with logistical support to private and commercial international users and research scientists.

But carving the way out of the wilderness isn’t going to be easy. First a site needs to be chosen and then the logistics need to be considered. According to SG director, Dr. Bert Candusio; “The end result ultimately dictates if the effort is justified. In this case, the northern Flinders Ranges consistently proved to be the best observatory location Australia has to offer. The other factor in our site selection was availability of research support in such a remote location. Fortunately, the Arkaroola Village is fully self-contained and maintains all manner of activities from machine workshops, plant and equipment facilities all the way to visitor interpretation staff, high speed internet capabilities and support.”

Dodwell <br> Observatory
Dodwell Observatory
While the thought of having a village nearby might seem like another access to light pollution, stargazers don’t need to worry. The Arkaroola Wilderness Sanctuary is also home to three astronomical institutions – Dodwell, Sir Mark Oliphant and R. Sprigg Observatories – and soon to be the Southern Galactic Mt. Spriggina Observatory. Located 4km south of the AWS village and high atop it own 425 meters peak, this new facility is expected to have six positions open to researchers and private individuals in late 2008, early 2009.

“The SG Mt. Spriggina location presents a unique opportunity for advanced research and astrophotography outcomes to organizations, educators and individuals to be operational under perhaps Australia’s foremost astromony location.” says Dr. Candusio. “The site’s uniqueness in such a remote location towards Central Australia’s wilderness has never been offered to the private and corporate sector internationally before. According to a commissioned report on the seeing quality of the northern Flinders Ranges, the area receives less cloud cover than any other region of the Australian mainland and the seeing FWHM figures were considerably better when compared to the Anglo Australia Telescope at Siding Springs location.”

So who will be manning the telescopes in a remote observatory? Nah. As cute and cuddly as the Euro ‘roo can be, the Southern Galactic facility will offer a professionally trained support staff to oversee operations. According to Dr. Candusio, “Since Arkaroola hosts numerous visitors , there are several permanent on-site staff available to conduct tours of the existing Observatory Facilities at Arkaroola. The experience of these individuals will play a vital role in helping to keep the Mount Spriggina site functioning at all times.”

Just how far would you go?

Posted on by Tammy Plotner

Weekend SkyWatchers Forecast – August 29 – 31, 2008

Greetings, fellow SkyWatchers… It’s New Moon weekend and what better way to celebrate than to fly with the Swan and the Eagle?! While we’re out, we’ll drop by the Trifid, check into this week’s upcoming meteor shower activity and take a challenging walk into the world of dark nebula. Are you ready? Then it’s time to head out into the night… Together.

Friday, August 29, 2008 – While we’ve got a great dark skies night on our hands, it’s a perfect opportunity for all optics to hunt down a star forming region about a palm’s width north of the lid star (Lambda) in the Sagittarius teapot as we seek out the “Omega”…

Easily viewed in binoculars of any size and outstanding in every telescope, the 5000 light-year distant Omega Nebula was discovered by Philippe Loys de Chéseaux in 1745-46 and later (1764) cataloged by Messier as object 17 (RA 18 20 26 Dec -16 10 36). This beautiful emission nebula is the product of hot gases excited by the radiation of newly born stars. As part of a vast region of interstellar matter, many of its embedded stars don’t show up in photographs, but reveal themselves beautifully to the eye at the telescope. As you look at its unique shape, you realize many of these areas are obscured by dark dust, and this same dust is often illuminated by the stars themselves.

Often known as “The Swan,” M17 will appear as a huge, glowing check mark or ghostly “2” in the sky – but power up if you use a larger telescope and look for a long, bright streak across its northern edge with extensions to both the east and north. While the illuminating stars are truly hidden, you will see many glittering points in the structure itself and at least 35 of them are true members of this region, which spans up to 40 light-years and could form up to 800 solar masses. It is awesome…

Now let’s continue our nebula hunt as we head about a fingerwidth north and just slightly west of M8 for the “Trifid”…

M20 (RA 18 02 23 Dec -23 01 48) was discovered by Messier on June 5, 1764; much to his credit he described it as a cluster of stars encased in nebulosity. This is truly a wonderful observation since the Trifid could not have been easy given his equipment. Some 20 years later William Herschel (although he tried to avoid repeating Messier objects) found M20 of enough interest to assign separate designations to parts of this nebula – IV.41, V.10, V.11, and V.12. The word “Trifid” was first used by John Herschel to describe its beauty.

While M20 is a very tough call in binoculars, it is not impossible with good conditions to see light from an area which left its home nearly a millennium ago. Even smaller scopes will pick up the round, hazy patch of both emission and reflection, but you will need aversion to see the dark nebula which divides it; this was cataloged by Barnard as B 85. Larger telescopes will find the Trifid as one of the very few objects that actually appears much in the eyepiece as it does in photographs – with each lobe containing beautiful details, rifts and folds best seen at lower powers. Look for its cruciform star cluster and its fueling multiple star system while you enjoy this triple treat tonight!

Saturday, August 30, 2008 – Today (in 1991) celebrates Yohkoh. The Yohkoh Mission was a joint effort of both Japan and the United States to launch a satellite to monitor the Sun’s corona and study solar flares. While the mission was quite successful, on December 14, 2001, the spacecraft’s signal was lost during a total eclipse. Controllers were unable to point the satellite back toward the Sun, so its batteries discharged and Yohkoh became inoperable.

Tonight is New Moon and while the darkest skies are on our side, we’ll fly with the “Eagle” as we hop another fingerwidth north of M17 to M16 (RA 18 18 48 Dec -13 49 00) and head for one of the most famous areas of starbirth, IC 4703…

While the open cluster NGC 6611 was discovered by Chéseaux in 1745-6, it was Charles Messier who cataloged the object as M16. And he was the first to note the nearby nebula IC 4703, now commonly known as the Eagle. At 7000 light-years distant, this roughly 7th magnitude cluster and nebula can be spotted in binoculars, but at best it is only a hint. As part of the same giant cloud of gas and dust as neighboring M17, the Eagle is also a place of starbirth illuminated by these hot, high energy stellar youngsters which are only about five and a half million years old.

In small to mid-sized telescopes, the cluster of around 20 brighter stars comes alive with a faint nebulosity that tends to be brighter in three areas. For larger telescopes, low power is essential. With good conditions, it is very possible to see areas of dark obscuration and the wonderful notch where the “Pillars of Creation” are located. Immortalized by the Hubble Space telescope, they won’t be nearly as grand or as colorful as the HST saw them, but what a thrill to know they are there!

Sunday, August 31 – Tonight we will begin entering the stream of the Andromedid meteor shower, which peaks off and on for the next couple of months. For those of you in the northern hemisphere, look for the lazy “W” of Cassiopeia to the northeast. This is the radiant – or relative point of origin – for this meteor stream. At times, this shower has been known to be spectacular, but let’s stick with an accepted fall rate of around 20 per hour. These are the offspring of Biela’s Comet, one that split apart in 1846 leaving radically different streams – much like 73/P Schwassman-Wachmann in 2006. These meteors have a reputation for red fireballs with spectacular trains, so watch for them in the weeks ahead.

While there’s still no Moon to interfere with the dark – let’s take another, more challenging, look at the “dark” as we head toward open cluster NGC 6520…

Located just slightly more than a fingerwidth above Gamma Sagittarii and 5500 light-years away, NGC 6520 (RA 18 03 24 Dec –27 53 00) is a galactic star cluster which formed millions of years ago. Its blue stars are far younger than our own Sun, and may very well have formed from what you don’t see nearby – a dark, molecular cloud. Filled with dust, Barnard 86 literally blocks the starlight coming from our galaxy’s own halo area in the direction of the core. To get a good idea of just how much light is blocked by B 86, take a look at the star SAO 180161 on the edge. Behind this obscuration lies the densest part of our Milky Way! This one is so dark that it’s often referred to as the “Ink Spot.”

While both NGC 6520 and B 86 are about the same distance away, they don’t reside in the hub of our galaxy, but in the Sagittarius Spiral Arm. Seen in binoculars as a small area of compression, and delightfully resolved in a telescope, you’ll find this cluster is on the Herschel “400” list and many others as well. Enjoy this rare pair tonight!

This week’s awesome images are: M17 – Credit: Hillary Mathis, N.A.Sharp, REU program/NOAO/AURA/NSF, M20 – NOAO/AURA/NSF, Yohkoh – Credit: NASA, M16 – Credit: Bill Schoening/NOAO/AURA/NSF and NGC 6520 and B 86 – Credit: Palomar Observatory, courtesy of Caltech. Thank you!!

Posted on by Nancy Atkinson

Satellite Images Show Arctic Ice At Another Low

The arrow shows the Northwest Passage, which is virtually ice free. Credit: ESA

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Envisat satellite observations from mid-August show that a new record of low polar sea-ice coverage in the Arctic could be reached in sometime in September. This follows last summer’s record minimum ice cover in the same area. Current ice coverage in the Arctic has already reached the second absolute minimum since observations from space began 30 years ago. Because the extent of ice cover is usually at its lowest about mid-September, this year’s minimum could still fall to set another record low.

Click here for an animation of ice coverage from early June to mid-August 2008.

The direct route through the Northwest Passage – highlighted in the image above by an orange line – is currently almost free of ice, while the indirect route, called the Amundsen Northwest Passage, has been passable for almost a month. This is the second year in a row that the most direct route through the Northwest Passage has opened up.

Each year, the Arctic Ocean experiences the formation and then melting of vast amounts of ice that floats on the sea surface. An area of ice the size of Europe melts away every summer reaching a minimum in September. Since satellites began surveying the Arctic in 1978, there has been a regular decrease in the area covered by ice in summer – with ice cover shrinking to its lowest level on record and opening up the most direct route through the Northwest Passage in September 2007.

“The polar regions, especially the Arctic, are very sensitive indicators of climate change,” said Prof. Heinrich Miller from the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. “The UN’s Intergovernmental Panel on Climate Change has shown that these regions are highly vulnerable to rising temperatures and predicted that the Arctic would be virtually ice-free in the summer months by 2070. Other scientists claim it could become ice-free as early as 2040. Latest satellite observations suggest that the Arctic could be mainly ice-free even earlier.”

Source: ESA

Posted on by Nancy Atkinson

Minimum Mass for Galaxies Provides Insight on Dark Matter

Dwarf galaxies that are within 500,000 light-years from the Milky Way. Credit: UCI

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More news on dark matter this week: By analyzing light from dwarf galaxies that orbit the Milky Way, scientists believe they have discovered the minimum mass for galaxies in the universe – 10 million times the mass of the sun. This mass could be the smallest known “building block” of the mysterious, invisible substance called dark matter. Stars that form within these building blocks clump together and turn into galaxies. Scientists know very little about the microscopic properties of dark matter, even though it accounts for approximately five-sixths of all matter in the universe. “By knowing this minimum galaxy mass, we can better understand how dark matter behaves, which is essential to one day learning how our universe and life as we know it came to be,” said Louis Strigari, lead author of this study from the University of California, Irvine.

Dark matter governs the growth of structure in the universe. Without it, galaxies like our own Milky Way would not exist. Scientists know how dark matter’s gravity attracts normal matter and causes galaxies to form. They also suspect that small galaxies merge over time to create larger galaxies such as our Milky Way.

The smallest known galaxies, called dwarf galaxies, vary greatly in brightness, from 1,000 times the luminosity of the sun to 10 million times the luminosity of the sun. At least 22 of these dwarf galaxies are known to orbit the Milky Way. UCI scientists studied 18 of them using data obtained with the Keck telescope in Hawaii and the Magellan telescope in Chile, with the goal of calculating their masses. By analyzing stars’ light in each galaxy, they determined how fast the stars were moving. Using those speeds, they calculated the mass of each galaxy.

The researchers expected the masses to vary, with the brightest galaxy weighing the most and the faintest galaxy weighing the least. But surprisingly all dwarf galaxies had the same mass – 10 million times the mass of the sun.

Manoj Kaplinghat, a study co-author and physics and astronomy assistant professor at UCI, explains this finding using an analogy in which humans play the role of dark matter.

“Suppose you are an alien flying over Earth and identifying urban areas from the concentration of lights in the night. From the brightness of the lights, you may surmise, for example, that more humans live in Los Angeles than in Mumbai, but this is not the case,” Kaplinghat said. “What we have discovered is more extreme and akin to saying that all metro areas, even those that are barely visible at night to the aliens, have a population of about 10 million.”

Since dwarf galaxies are mostly dark matter – the ratio of dark matter to normal matter is as large as 10,000 to one – the minimum-mass discovery reveals a fundamental property of dark matter.

“We are excited because these galaxies are virtually invisible, yet contain a tremendous amount of dark matter,” said James Bullock, a study co-author and director of UCI’s Center for Cosmology. “This helps us better understand the particle that makes up dark matter, and it teaches us something about how galaxies form in the universe.”

The scientists say clumps of dark matter may exist that contain no stars. The only dark matter clumps they can detect right now are those that are lit by stars.

Scientists hope to learn about dark matter’s microscopic properties when the Large Hadron Collider in Switzerland becomes operational later this year. The device will accelerate two beams of nuclei in a ring in opposite directions and then slam them together to recreate conditions just after the Big Bang. By doing this, scientists hope to create the dark matter particle in the lab for the first time.

Source: University of California, Irvine

Posted on by Nancy Atkinson

Astronomers Locate High Energy Emissions from the Crab Nebula

Crab Nebula. Credit: NASA/ESA

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Scientists studying the Crab Nebula have discovered high energy gamma rays around the rotation-powered pulsar, the neutron star at the center of this enigmatic nebula. Neutron stars accelerate particles to immense energies, typically one hundred times more than the most powerful accelerators on Earth. Scientists have been uncertain exactly how these systems work and where the particles are accelerated. But by using the gamma-ray telescope on the European Space Agency’s INTEGRAL spacecraft orbiting Earth, astronomers have detected polarized gamma-rays emitting from near the pulsar.

The Crab Nebula was created by a supernova explosion which was seen from Earth by early Chinese and Arab astronomers on July 4, 1054. The explosion left behind a pulsar or rotating neutron star with a nebula of radiating particles around it.

The Crab Pulsar. This image combines optical data from Hubble (in red) and X-ray images from Chandra X-ray Observatory (in blue).
The Crab Pulsar. This image combines optical data from Hubble (in red) and X-ray images from Chandra X-ray Observatory (in blue).

The neutron star contains the mass of the Sun squeezed into a volume of about 10 km radius, rotating very fast – about 30 times a second – thereby generating magnetic fields and accelerating particles. But until now, astronomers didn’t know exactly where the particles were accelerated.
Looking into the heart of the pulsar with Integral’s spectrometer (SPI), the researchers made a detailed study of over 600 observations to assess the polarization – or the alignment – of the waves of high-energy radiation originating from the Crab.

They saw that this polarized radiation is aligned with the rotation axis of the pulsar. So they concluded that a significant portion of the electrons generating the high-energy radiation must originate from a highly-organized structure located very close to the pulsar, very likely directly from the jets themselves. The discovery allows the researchers to discard other theories that locate the origin of this radiation further away from the pulsar.

Credits: NASA/CXC/ASU/J. Hester et al.(for the Chandra image); NASA/HST/ASU/J. Hester et al. (for the Hubble image)
Credits: NASA/CXC/ASU/J. Hester et al.(for the Chandra image); NASA/HST/ASU/J. Hester et al. (for the Hubble image)

Professor Tony Dean of the University’s School of Physics and Astronomy, and one of the researchers, commented that the discovery of such alignment – also matching with the polarization observed in the visible band – is truly remarkable. “The findings have clear implications on many aspects of high energy accelerators such as the Crab,” he added.

“The detection of polarized radiation in space is very complicated and rare, as it requires dedicated instrumentation and an in-depth analysis of very complex data”, said Chris Winkler, Integral Project Scientist at ESA.

The paper ‘Polarized gamma-ray emission from the Crab’ is published this week in Science.

More information about the Integral Spacecraft.

Sources: ESA

Posted on by Nancy Atkinson

Space Station Evades Space Debris

ISS. Credit: NASA

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The International Space Station had to perform an evasive maneuver yesterday to dodge space debris from a Russian satellite that disintegrated earlier this year. ESA’s ATV (Automated Transfer Vehicle) was used to perform the avoidance maneuver, the first time it had been used for such a maneuver. A few things about this maneuver are interesting. First, this is the first time in five years that the ISS has had to perform a debris avoidance maneuver. Second, the maneuver was unusual in that was a retrograde maneuver, which slows the ISS and brings it to a lower orbit instead of higher. The last time a retrograde maneuver was performed was eight years ago. Third, according to Jim Oberg at MSNBC, the Russians deny that the satellite has broken up. Fourth, however, the Mission Control Center in Moscow carried out the maneuver.

The maneuver began on August 27 at 18:11 CEST (16:11 UT) and finished 5 minutes 2 seconds later.
In the current ISS configuration the ATV, which is docked to the aft end of the Russian Zvezda Service module at the back of the station, is the only vehicle that can carry out this kind of maneuver. First, the station was turned 180 degrees so that ATV’s aft thrusters were at the front of the ISS with respect to the station’s flight profile.

Once turned, Jules Verne ATV used its rear thrusters produce a speed of 1 m/s to slow the Station down, lowering it about 1.5 kilometers (1 mile). The space station orbits between 320-400 km (200-250 miles) above the Earth’s surface.

Usually maneuvers raise the orbital altitude in order to compensate for the continual drag the station encounters from the upper atmosphere. But Oberg reported that “because the station is now operating near the upper end of its allowable altitude range, any further increase could have exceeded the lifting performance of planned docking missions over the next few months. Hence NASA had to make the unavoidable and wasteful choice to go in the opposite direction.”

The satellite was a Russian Cosmos-2421 naval surveillance satellite, launched in 2006 and designed for electronic eavesdropping to keep track of Western military vessels. According to U.S. tracking data, the satellite disintegrated on March 14 into hundreds of pieces, and later disintegrated further resulting in over 500 tracked objects, one of the largest debris clouds in space history. But Russian officials say the satellite has not broken up, but only quit working. Find more info on this at MSNBC.

Once the debris avoidance maneuver was complete, the ISS was turned back to its original orbital attitude, and control of the ATV was handed back to the ATV Control Center in Europe.

Sources: ESA, MSNBC

Posted on by Nancy Atkinson

Still Mythbusting

Lunar Landing
Apollo 11 Lunar Module on it way to the moon. Credit: NASA

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It seems fitting that today’s NASA “Image of the Day” is this wonderful image of the lunar lander from the Apollo 11 mission, the Eagle, on its way to land on the moon. Really, truthfully, can anyone really believe that a spectacular image like this can be fake? After last night’s “Mythbusters” show about the Apollo Moon Landing Hoax Myth, I’m cautiously hopeful that at least some people who believe(d) in this myth had their eyes opened and minds changed. Alas, there will always be folks out there who for some reason are set on not believing scientists, engineers or the government and won’t subscribe to any type of proof, be it scientific or television-ific. Perhaps the upcoming Lunar Reconnaissance Orbiter mission will be able to take hi-resolution images of one of the Apollo sites.

But in the meantime, enjoy this great image, taken by the Columbia Command and Service Module Pilot for Apollo 11, Michael Collins. Inside the Eagle were Commander Neil A. Armstrong and Lunar Module Pilot Buzz Aldrin. The long rod-like protrusions under the landing pods are lunar surface sensing probes. Upon contact with the lunar surface, the probes sent a signal to the crew to shut down the descent engine. And then Armstrong said, “Houston, Tranquility Base here. The Eagle has landed.”

And that’s the truth.

For more great NASA images, visit the Image of the Day site

Posted on by Nancy Atkinson

Earth’s Atmosphere is Leaking into Space

Artist impression of ions leaking into space. Credit: NASA/ESA

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Oxygen is constantly leaking out of Earth’s atmosphere and into space. Measurements taken by satellites during the 1980s and 1990s showed the escaping ions were traveling faster the higher they were observed. This implied that some sort of acceleration mechanism was involved. Now, new work on data collected by a group of formation-flying satellites called Cluster shows that Earth’s own magnetic field is accelerating the oxygen away. But don’t worry, compared to the Earth’s stock of the life-supporting gas, the amount escaping is negligible. However, in the far future when the Sun begins to heat up in old age, the balance might change and the oxygen escape may become significant.

From data collected from 2001 to 2003, Cluster amassed information about beams of electrically charged oxygen atoms, known as ions, flowing outwards from the polar regions into space. Cluster also measured the strength and direction of the Earth’s magnetic field whenever the beams were present.

Hans Nilsson, Swedish Institute of Space Physics, headed a team of space scientists who analyzed the data. They discovered that the oxygen ions were being accelerated by changes in the direction of the magnetic field. “It is a bit like a sling-shot effect,” says Nilsson.

Having all four Cluster spacecraft was essential to the analysis because it gave astronomers a way to measure the strength and direction of the magnetic field over a wide area. “Cluster allowed us to measure the gradient of the magnetic field and see how it was changing direction with time,” says Nilsson.

Before the space age, scientists believed that Earth’s magnetic field was filled only with particles from the solar wind, the constant sleet of particles that escapes from the Sun. They thought this formed a large cushion that protected the Earth’s atmosphere from direct interaction with the solar wind.

“We are beginning to realize just how many interactions can take place between the solar wind and the atmosphere,” says Nilsson. Energetic particles from the solar wind can be channeled along the magnetic field lines and, when these impact the atmosphere of the Earth, they can produce aurorae. This occurs over the poles of Earth. The same interactions provide the oxygen ions with enough energy to accelerate out of the atmosphere and reach the Earth’s magnetic environment.

The Cluster data were captured over the poles with the satellites flying at an altitude of anywhere between 30,000 and 64,000 kilometers. The data is helping scientists to understand what might happen in the future. “We can only predict these future changes if we understand the mechanisms involved,” says Nilsson.

Source: ESA

Posted on by Ian O'Neill

NASA Security Badges are a Health and Safety Risk

NASA Security Badge (Identity Stronghold)

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Of all the things that could possibly go wrong for the US space agency, you wouldn’t expect the security ID badge holder of NASA employees to rank very high on the list of “risks.” Unfortunately, the new high-tech security badge holders recently issued to NASA employees have been identified as having a fairly problematic health and safety design flaw. Should the badges’ metal clasps be installed incorrectly, they could pose a projectile risk, possibly causing serious eye injuries…

Admittedly, this isn’t big news in the realms of the space exploration, but it is news nonetheless, proving that even NASA cannot escape from clerical design flaws. In an effort to fall in line with President Bush’s Homeland Security Presidential Directive-12, NASA employees have to carry a new type of badge which is protected against being read from a distance and also provides the wearer with some freedom as to when they want to show it. Unfortunately, there is a design flaw with the badge and on August 15th, NASA had to issue a warning to Kennedy Space Center employees stating that the new Identity Stronghold badge holder has the “potential to introduce dangerous Foreign Object Damage (FOD) to flight hardware areas and can cause personnel injury if the metal clips are installed improperly.”

According to new guidelines, when removing the badge, the employee must not aim the metal clips at a colleague as it could create a potential eye injury hazard, technically known as Foreign (or Flying) Object Damage (FOD). I’d imaging this being an acute problem during security checks, guards flinching as employees show their badges, fearful of a metal clasp flying at their faces. Not only that, employees are advised not to play with their badges around sensitive electronics:

“The badge holder may separate with little effort, allowing the clips, the front half of the holder and badge ID to separate creating a significant FOD hazard in controlled areas […] Personnel should ensure the badge holder is not worn, or is properly secured, in the vicinity of sensitive flight hardware, such as electronics, where FOD may be an issue […] When removing your badge, do not point [the] end with metal clips towards your face or another person.” – Randy Aden, Office of Protective Services, Jet Propulsion Lab.

Use of the badge holder, made by the Florida-based company Identity Stronghold, has now been suspended and a temporary clear plastic holder is being used in its place. The Stronghold design was chosen as it has an “electromagnetically opaque sleeve to prevent the card from being read at a distance and to give the user some control over when and where the card is exposed for reading,” according to the source Information Week article.

Interestingly, the Identity Stronghold website proudly states that its Secure Badgeholder “has been awarded the 2008 GOOD DESIGN award for product design.” I don’t think the “GOOD DESIGN” award was good enough.

Fortunately there have been no reports of serious card holder-related FOD injuries so far. Who would have thought an ID badge could be so dangerous?

Source: Information Week