samedi 4 février 2012

What to expect from the LHC in 2012












CERN - European Organization for Nuclear Research logo.

Feb. 4, 2012

The CERN LHC

The Large Hadron Collider (LHC), the world's largest particle accelerator, is currently shut down for annual maintenance. In February CERN will decide whether to run the LHC at a total energy of 8 TeV this year, instead of 7 TeV as in 2011. Higher energy should increase the chances of finding heavy particles. By early March, all the magnets around the 27-kilometre accelerator will have been cooled down to their operating temperatures of -271.3°C, ready to guide beams of particles through the LHC.

The LHC will resume colliding protons in late March. The goal is to deliver about 1600 trillion proton-proton collisions (16 "inverse femtobarns" of data) to the experiments, compared to the 500 trillion collisions delivered in 2011. More collisions will help the LHC experiments to improve the precision of their measurements and push searches for new physics further.

Engineers at work on the ATLAS calorimeter during last year's maintenance shutdown. Image: CERN

The CMS and ATLAS experiments will continue to look for new particles this year, of which the Higgs boson is the most publicized. Data taken in 2012 will allow them either to confirm a Higgs discovery or to rule out its existence conclusively.

The LHCb experiment will carry on with its precise measurements of quarks, in the search for weak points in the current Standard Model of particle physics. Meanwhile, ALICE is analyzing lead-ion collision data taken in November 2011 in the quest to understand how quark-gluon plasma formed after the Big Bang. More heavy-ion collisions are scheduled for November this year.

Stay tuned for more from CERN in 2012!

Note:

The European Organization for Nuclear Research (French: Organisation européenne pour la recherche nucléaire), known as CERN, is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border. Established in 1954, the organization has twenty European member states.

The term CERN is also used to refer to the laboratory itself, which employs just under 2400 full-time employees/workers, as well as some 7931 scientists and engineers representing 608 universities and research facilities and 113 nationalities.

More information:

    Quantum diaries: 2012 – The year of the dragon: http://www.quantumdiaries.org/2012/01/20/2012-the-year-of-the-dragon/

    ATLAS: http://atlas.ch/

    CMS: http://cms.web.cern.ch/

    LHCb: http://lhcb-public.web.cern.ch/lhcb-public/

    ALICE: http://aliceinfo.cern.ch/Public/Welcome.html

Images, Text, Credit: CERN.

Greetings, Orbiter.ch

vendredi 3 février 2012

Mars Express reveals wind-blown deposits on Mars












ESA - Mars Express Mission patch.

3 February 2012

New images from ESA’s Mars Express show the Syrtis Major region on Mars. Once thought to be a sea of water, the region is now known to be a volcanic province dating back billions of years.

Syrtis Major can be spotted from Earth even with relatively small telescopes – the near-circular dark area on the planet stretches over 1300 x 1500 km.

Part of Syrtis Major

Christiaan Huygens discovered this area in 1659 and by repeated observations he used it to time the length of day on Mars.

Early ideas held that it was a sea with a water level that rose and fell, causing the markings to change.

Now, however, we know that the region is volcanic in origin, devoid of water and that the changes in its shape are due to dust and sand being blown around in the wind.

Syrtis Major in context

Newly released images of a part of Syrtis Major seen from ESA’s Mars Express orbiter show lava flows that flooded the older highland material, leaving behind buttes – isolated hills with steep sides that were too high to be affected.

They can be identified by their lighter colours and their eroded state, and some even show ancient valleys on their flanks.

Syrtis Major features

Individual lava flows, filled craters and partly-filled craters can be made out in the images. The prevailing wind direction can be seen from the dispersal of the lighter-toned dust and darker-toned sand in and around the craters and buttes. The smaller craters illustrate this clearly.

The largest crater in the pictures has a small central peak and contains a small dune field of darker-toned dunes to the east of its floor.

Syrtis Major elevation

The number and size of craters can be used to date surfaces in the Solar System because craters slowly accumulate as impacts occur over time. This information can be used to date the volcanic province and suggests an age of over 3 billion years.

Syrtis Major high resolution

Syrtis Major perspective

Syrtis Major perspective 

Syrtis Major perspective

Syrtis Major perspective

Syrtis Major 3D

Related links:

High Resolution Stereo Camera: http://berlinadmin.dlr.de/Missions/express/indexeng.shtml

Behind the lens: http://www.esa.int/SPECIALS/Mars_Express/SEMSXE1PGQD_0.html

Frequently asked questions: http://www.esa.int/SPECIALS/Mars_Express/SEM76D9OY2F_0.html

For specialists:
ESA Planetary Science archive (PSA): http://www.rssd.esa.int/PSA

NASA Planetary Data System: http://pds-geosciences.wustl.edu/missions/mars_express/hrsc.htm

HRSC data viewer: http://hrscview.fu-berlin.de/

Images, Text, Credits: ESA / DLR / FU Berlin (G. Neukum)/Credits: NASA MGS MOLA Science Team.

Best regards, Orbiter.ch

Classic Portrait of a Barred Spiral Galaxy












ESA - Hubble Space Telescope logo.

3 February 2012

 Hubble image of NGC 1073

The NASA/ESA Hubble Space Telescope has taken a picture of the barred spiral galaxy NGC 1073, which is found in the constellation of Cetus (The Sea Monster). Our own galaxy, the Milky Way, is a similar barred spiral, and the study of galaxies such as NGC 1073 helps astronomers learn more about our celestial home.

Most spiral galaxies in the Universe have a bar structure in their centre, and Hubble’s image of NGC 1073 offers a particularly clear view of one of these. Galaxies’ star-filled bars are thought to emerge as gravitational density waves funnel gas toward the galactic centre, supplying the material to create new stars. The transport of gas can also feed the supermassive black holes that lurk in the centres of almost every galaxy.

Labelled Hubble image of NGC 1073, showing quasars and IXO 5

Some astronomers have suggested that the formation of a central bar-like structure might signal a spiral galaxy's passage from intense star-formation into adulthood, as the bars turn up more often in galaxies full of older, red stars than younger, blue stars. This storyline would also account for the observation that in the early Universe, only around a fifth of spiral galaxies contained bars, while more than two thirds do in the more modern cosmos.

While Hubble’s image of NGC 1073 is in some respects an archetypal portrait of a barred spiral, there are a couple of quirks worth pointing out.

Wide-field view of NGC 1073 and its surroundings (ground-based image)

One, ironically, is almost — but not quite — invisible to optical telescopes like Hubble. In the upper left part of the image, a rough ring-like structure of recent star formation hides a bright source of X-rays. Called IXO 5, this X-ray source is likely to be a binary system featuring a black hole and a star orbiting each other. Comparing X-ray observations from the Chandra spacecraft with this Hubble image, astronomers have narrowed the position of IXO 5 down to one of two faint stars visible here. However, X-ray observations with current instruments are not precise enough to conclusively determine which of the two it is.

Hubble’s image does not only tell us about a galaxy in our own cosmic neighbourhood, however. We can also discern glimpses of objects much further away, whose light tells us about earlier eras in cosmic history.

video
Zoom into NGC 1073

Right across Hubble’s field of view, more distant galaxies are peering through NGC 1073, with several reddish examples appearing clearly in the top left part of the frame.

video
Pan across NGC 1073

More intriguing still, three of the bright points of light in this image are neither foreground stars from the Milky Way, nor even distant stars in NGC 1073. In fact they are not stars at all. They are quasars, incredibly bright sources of light caused by matter heating up and falling into supermassive black holes in galaxies literally billions of light-years from us. The chance alignment through NGC 1073, and their incredible brightness, might make them look like they are part of the galaxy, but they are in fact some of the most distant objects observable in the Universe.

Notes:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

Links:

    Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

Images, Videos, Text, Credit: NASA & ESA.

Greetings, Orbiter.ch

jeudi 2 février 2012

Dione on a Diagonal












NASA / ESA - Cassini Mission to Saturn patch.

Feb. 2, 2012


Image above: Saturn and Dione appear askew in this Cassini spacecraft view, with the north poles rotated to the right, as if they were threaded along on the thin diagonal line of the planet's rings.

This view looks toward the anti-Saturn side of Dione (698 miles, or 1,123 kilometers across). North on Dione is up and rotated 20 degrees to the right. This view looks toward the northern, sunlit side of the rings from less than one degree above the ring plane.

The image was taken in visible green light with the Cassini spacecraft wide-angle camera on Dec. 12, 2011. The view was obtained at a distance of approximately 35,000 miles (57,000 kilometers) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 41 degrees.

For more information about the Cassini-Huygens mission visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org

Dione's image gallery: http://www.nasa.gov/mission_pages/cassini/multimedia/gallery-indexDione.html

Image, Text, Credit: NASA / JPL-Caltech / Space Science Institute.

Cheers, Orbiter.ch

mercredi 1 février 2012

NASA Mission Returns First Video From Moon's Far Side











NASA - GRAIL Mission patch.

02.01.12

video

NASA's GRAIL mission has beamed back its first video of the far side of the moon. The imagery was taken on Jan. 19 by the MoonKAM aboard the mission's "Ebb" spacecraft.

A camera aboard one of NASA's twin Gravity Recovery And Interior Laboratory (GRAIL) lunar spacecraft has returned its first unique view of the far side of the moon. MoonKAM, or Moon Knowledge Acquired by Middle school students, will be used by students nationwide to select lunar images for study.

GRAIL consists of two identical spacecraft, recently named Ebb and Flow, each of which is equipped with a MoonKAM. The images were taken as part of a test of Ebb's MoonKAM on Jan. 19. The GRAIL project plans to test the MoonKAM aboard Flow at a later date.


Image above: South pole of the far side of the moon as seen from the GRAIL mission’s Ebb spacecraft. Image credit: NASA / JPL-Caltech.

To view the 30-second video clip, visit: http://go.nasa.gov/zZXAPs .

In the video, the north pole of the moon is visible at the top of the screen as the spacecraft flies toward the lunar south pole. One of the first prominent geological features seen on the lower third of the moon is the Mare Orientale, a 560-mile-wide (900 kilometer) impact basin that straddles both the moon's near and far side.

The clip ends with rugged terrain just short of the lunar south pole. To the left of center, near the bottom of the screen, is the 93-mile-wide (149 kilometer) Drygalski crater with a distinctive star-shaped formation in the middle. The formation is a central peak, created many billions of years ago by a comet or asteroid impact.

"The quality of the video is excellent and should energize our MoonKAM students as they prepare to explore the moon," said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge.

The twin spacecraft successfully achieved lunar orbit this past New Year's Eve and New Year's Day. Previously named GRAIL-A and GRAIL-B, the washing machine-sized spacecraft received their new names from fourth graders at the Emily Dickinson Elementary School in Bozeman, Mont., following a nationwide student naming contest.

Thousands of fourth- to eighth-grade students will select target areas on the lunar surface and send requests to the GRAIL MoonKAM Mission Operations Center in San Diego. Photos of the target areas will be sent back by the satellites for students to study. The MoonKAM program is led by Sally Ride, America's first woman in space. Her team at Sally Ride Science and undergraduate students at the University of California in San Diego will engage middle schools across the country in the GRAIL mission and lunar exploration. GRAIL is NASA's first planetary mission carrying instruments fully dedicated to education and public outreach.

"We have had great response from schools around the country; more than 2,500 signed up to participate so far," Ride said. "In mid-March, the first pictures of the moon will be taken by students using MoonKAM. I expect this will excite many students about possible careers in science and engineering."

Launched in September 2011, Ebb and Flow periodically perform trajectory correction maneuvers that, over time, will lower their orbits to near-circular ones with an altitude of about 34 miles (55 kilometers). During their science mission, the duo will answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the GRAIL mission for NASA's Science Mission Directorate in Washington. The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver built the spacecraft.

For more information about GRAIL, visit: http://www.nasa.gov/grail .

Information about MoonKAM is available at: https://moonkam.ucsd.edu .

JPL is managed for NASA by the California Institute of Technology in Pasadena.

Image (mentioned), Video, Text, Credits: NASA / JPL / DC Agle / Dwayne Brown.

Best regards, Orbiter.ch

Remnant of an Explosion With a Powerful Kick?

NASA - Chandra X-ray Observatory patch.

02.01.12


Vital clues about the devastating ends to the lives of massive stars can be found by studying the aftermath of their explosions. In its more than twelve years of science operations, NASA's Chandra X-ray Observatory has studied many of these supernova remnants sprinkled across the Galaxy.

The latest example of this important investigation is Chandra's new image of the supernova remnant known as G350.1+0.3. This stellar debris field is located some 14,700 light years from the Earth toward the center of the Milky Way.

Evidence from Chandra and from ESA's XMM-Newton telescope suggest that a compact object within G350.1+0.3 may be the dense core of the star that exploded. The position of this likely neutron star, seen by the arrow pointing to "neutron star" in the inset image, is well away from the center of the X-ray emission. If the supernova explosion occurred near the center of the X-ray emission then the neutron star must have received a powerful kick in the supernova explosion.

Data from Chandra and other telescopes suggest this supernova remnant, as it appears in the image, is between 600 and 1,200 years old. If the estimated location of the explosion is correct, this means that the neutron star has been moving at a speed of at least 3 million miles per hour since the explosion This is comparable to the exceptionally high speed derived for the neutron star in Puppis A, another neutron star moving at a blistering pace within a supernova remnant. The G350+1+0.3 data provide new evidence that extremely powerful "kicks" may be imparted to neutron stars left behind once the supernova has exploded.

Another intriguing aspect of G350.1+0.3 is its unusual shape. While many supernova remnants are nearly circular, G350.1+0.3 is strikingly asymmetrical as seen in the Chandra data in this image (gold). Infrared data from NASA's Spitzer Space Telescope (light blue) also trace the morphology found by Chandra. Astronomers think that this bizarre shape is due to stellar debris field expanding into a nearby cloud of cold molecular gas.

The age of 600-1200 years puts the explosion that created G350.1+0.3 in the same time frame as other famous supernovas that formed the Crab and SN 1006 supernova remnants. However, it is unlikely that anyone on Earth would have seen the explosion because of the obscuring gas and dust that lies along our line of sight to the remnant.

These results appeared in the April 10, 2011 issue of The Astrophysical Journal. The scientists on this paper were Igor Lovchinsky and Patrick Slane (Harvard-Smithsonian Center for Astrophysics), Bryan Gaensler (University of Sydney, Australia), Jack Hughes (Rutgers University), Jasmina Lazendic (Monash University Clayton, Australia), Joseph Gelfand (New York University, Abu Dhabi), and Crystal Brogan (National Radio Astronomy Observatory).

Image, Credits: X-ray: NASA / CXC / SAO / I. Lovchinsky et al; IR: NASA / JPL-Caltech.

Read more/access all images: http://chandra.harvard.edu/photo/2012/g350/

View Chandra Flickr Photoset: http://www.flickr.com/photos/28634332@N05/sets/72157606205297786/

Image (mentioned), Text, Credits: NASA / Marshall Space Flight Center / Janet Anderson / Chandra X-ray Center / Megan Watzke.

Greetings, Orbiter.ch

A Pocket of Star Formation












ESO - European Southern Observatory logo.

1 February 2012

 The star formation region NGC 3324

This new view shows a stellar nursery called NGC 3324. It was taken using the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. The intense ultraviolet radiation from several of NGC 3324's hot young stars causes the gas cloud to glow with rich colours and has carved out a cavity in the surrounding gas and dust.

NGC 3324 is located in the southern constellation of Carina (The Keel, part of Jason’s ship the Argo) roughly 7500 light-years from Earth. It is on the northern outskirts of the chaotic environment of the Carina Nebula, which has been sculpted by many other pockets of star formation (eso0905). A rich deposit of gas and dust in the NGC 3324 region fuelled a burst of starbirth there several millions of years ago and led to the creation of several hefty and very hot stars that are prominent in the new picture.

The star formation region NGC 3324 in the constellation of Carina (The Keel)

Stellar winds and intense radiation from these young stars have blown open a hollow in the surrounding gas and dust. This is most in evidence as the wall of material seen to the centre right of this image. The ultraviolet radiation from the hot young stars knocks electrons out of hydrogen atoms, which are then recaptured, leading to a characteristic crimson-coloured glow as the electrons cascade through the energy levels, showing the extent of the local diffuse gas. Other colours come from other elements, with the characteristic glow from doubly ionised oxygen making the central parts appear greenish-yellow.

As with clouds in the Earth's sky, observers of nebulae can find likenesses within these cosmic clouds. One nickname for the NGC 3324 region is the Gabriela Mistral Nebula, after the Nobel Prize-winning Chilean poet [1]. The edge of the wall of gas and dust at the right bears a strong resemblance to a human face in profile, with the "bump" in the centre corresponding to a nose.

Digitized Sky Survey Image of Eta Carinae Nebula

The power of the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory also reveals many dark features in NGC 3324. Dust grains in these regions block out the light from the background glowing gas, creating shadowy, filigree features that add another layer of evocative structure to the rich vista.

video
 Zooming in on the star formation region NGC 3324

The sharp sight of the Hubble Space Telescope has also been trained on NGC 3324 in the past. Hubble can pick out finer details than the panoramic view of the Wide Field Imager, but only over a much smaller field of view. The two instruments when used in tandem can provide both "zoomed-in" and "zoomed-out" perspectives.

Notes:

[1] Further explanation and comparison images can be found on the site of the amateur astronomer Daniel Verschatse: http://www.verschatse.cl/nebulae/ngc3324/medium.htm.

More information:

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 40-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

    Photos of La Silla: http://www.eso.org/public/images/archive/category/lasilla/

Images, Text, Credits: ESO / Digitized Sky Survey 2. Acknowledgment: Davide De Martin / Video: ESO/Nick Risinger (skysurvey.org) / Digitized Sky Survey 2. Music: John Dyson (from the album Moonwind).

Greetings, Orbiter.ch

mardi 31 janvier 2012

NASA Spacecraft Reveals New Observations of Interstellar Matter












NASA - IBEX patch.

Jan. 31, 2012

NASA's Interstellar Boundary Explorer (IBEX) has captured the best and most complete glimpse yet of what lies beyond the solar system. The new measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and the history of other stars in the Milky Way.

video

Video above: IBEX has directly sampled multiple heavy elements from the Local Interstellar Cloud for the first time. Credit: NASA/Goddard Scientific Visualization Studio.

The Earth-orbiting spacecraft observed four separate types of atoms including hydrogen, oxygen, neon and helium. These interstellar atoms are the byproducts of older stars, which spread across the galaxy and fill the vast space between stars. IBEX determined the distribution of these elements outside the solar system, which are flowing charged and neutral particles that blow through the galaxy, or the so-called interstellar wind.

"IBEX is a small Explorer mission and was built with a modest investment," said Barbara Giles, director of the Heliophysics Division at NASA Headquarters in Washington. "The science achievements though have been truly remarkable and are a testament to what can be accomplished when we give our nation's scientists the freedom to innovate."

In a series of science papers appearing in the Astrophysics Journal on Jan. 31, scientists report finding 74 oxygen atoms for every 20 neon atoms in the interstellar wind. In our own solar system, there are 111 oxygen atoms for every 20 neon atoms. This translates to more oxygen in any part of the solar system than in nearby interstellar space.

video

Video above: Neutral atoms from the galactic wind sweep past the solar system's magnetic boundary, the heliosheath, and travel some 30 years into our solar system toward the sun. NASA's Interstellar Boundary Explorer (IBEX) can observe those atoms and provide information about the mysterious neighborhood outside our home. Credit: NASA / Goddard Conceptual Image Lab.

"Our solar system is different than the space right outside it, suggesting two possibilities," says David McComas, IBEX principal investigator, at the Southwest Research Institute in San Antonio. "Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside, or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space."

The new results hold clues about the history of material in the universe. While the big bang initially created hydrogen and helium, only the supernovae explosions at the end of a star's life can spread the heavier elements of oxygen and neon through the galaxy. Knowing the amounts of elements in space may help scientists map how our galaxy evolved and changed over time.


NASA's Interstellar Boundary Explorer (IBEX) has found that there's more oxygen in our solar system than there is in the nearby interstellar material. That suggests that either the sun formed in a different part of the galaxy or that outside our solar system life-giving oxygen lies trapped in dust or ice grains unable to move freely in space. Credit: NASA / Goddard.

Scientists want to understand the composition of the boundary region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere. The heliosphere acts as a protective bubble that shields our solar system from most of the dangerous galactic cosmic radiation that otherwise would enter the solar system from interstellar space.

IBEX measured the interstellar wind traveling at a slower speed than previously measured by the Ulysses spacecraft, and from a different direction. The improved measurements from IBEX show a 20 percent difference in how much pressure the interstellar wind exerts on our heliosphere.


Image above: The galactic wind streams toward the sun from the direction of Scorpio and IBEX has found that it travels at 52,000 miles an hour. The speed of the galactic wind and its subsequent pressure on the outside of the solar system's boundary affects the shape of the heliosphere as it travels through space. Credit: NASA / Goddard Scientific Visualization Studio.

"Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there will help determine the size and shape of our solar system as it travels through the galaxy," says Eric Christian, IBEX mission scientist, at NASA's Goddard Space Flight Center in Greenbelt, Md.

The IBEX spacecraft was launched in October 2008. Its science objective is to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system.


Image above: NASA's Interstellar Boundary Explorer (IBEX) studies the outer boundaries of the solar system where particles from the solar wind collide with particles from the galactic wind. Credit: NASA.

The Southwest Research Institute developed and leads the IBEX mission with a team of national and international partners. The spacecraft is one of NASA's series of low-cost, rapidly developed missions in the Small Explorers Program. Goddard manages the program for the agency's Science Mission Directorate at NASA Headquarters in Washington.

For more information about IBEX,visit: http://www.nasa.gov/ibex

Additional downloadable media: http://svs.gsfc.nasa.gov/goto?10906

Images (mentioned), Videos (mentioned), Text, Credit: NASA / Goddard Space Flight Center / Karen C. Fox.

Best regards, Orbiter.ch

Space Station manoeuvres to avoid space debris












ISS - International Space Station patch.

31 January 2012

The International Space Station safely boosted itself to a higher altitude on 28 January to avoid possible collisions with orbital debris. The manoeuvre underscores the continuing need for comprehensive knowledge of orbital objects, a capability that Europe lacks.

The International Space Station burned its thrusters for 64 seconds last Saturday night to raise its orbit and avoid a series of potential collisions with debris from the 2007 explosion of China's Fengyun-1C weather satellite.

The burn began at 23:50 GMT using the main thrusters on the Zvezda module. The burn raised Station altitude by 1.9 km to an average height of 391.7 km. 

By firing the thrusters then, the Station also lined itself up for future operations, eliminating the need for a boost that had been set for today.

ISS with ATV Johannes Kepler and Shuttle Endeavour docked

"Space debris is a persistent threat to activity in space," says Emmet Fletcher, manager for space surveillance and tracking at ESA's Space Situational Awareness (SSA) programme office.

"Being able to provide accurate and reliable warnings to spacecraft operators allows a higher level of confidence when planning avoidance manoeuvres like this one."

"This saves on fuel and resources, and reduces mission disruption, which leads to a longer spacecraft operational life."

ESA's SSA programme, in part, aims to improve current European capabilities to track and observe objects, and to develop new resources for providing accurate debris warnings so as to make space a safer place for everyone.

For more information about SSA, visit: http://www.esa.int/esaMI/SSA/index.html

For more information about ISS, visit: http://www.nasa.gov/mission_pages/station/main/index.html

Image, Text, Credits: ESA / NASA.

Cheers, Orbiter.ch

Legendary Astronaut Shannon Lucid Retires From NASA










NASA logo.

Jan. 31, 2012

Shannon Lucid, a member of NASA's first astronaut class to include women, has retired after more than three decades of service to the agency.

A veteran of five spaceflights, Lucid logged more than 223 days in space, and from August 1991 to June 2007, held the record for the most days in orbit by any woman in the world. Lucid is the only American woman to serve aboard the Russian Mir space station. She lived and worked there for more than 188 days, the longest stay of any American on that vehicle. Her time on Mir also set the single flight endurance record by a woman until Suni Williams broke it in 2006.

"Shannon is an extraordinary woman and scientist. She paved the way for so many of us," said Peggy Whitson, chief of NASA's Astronaut Office at the Johnson Space Center in Houston. "She was a model astronaut for long-duration missions, and whether she was flying hundreds of miles up in space or serving as Capcom [capsule communicator] during the overnight hours for our space shuttle and space station crews, she always brought a smile to our faces. Like so many others, I always will look up to her."

Astronaut Shannon Lucid

Lucid, who holds a doctorate in biochemistry, was selected by NASA in 1978. She joined five other women as the agency's first female astronauts. Her first three shuttle missions deployed satellites. STS-51G in 1985 deployed and retrieved the SPARTAN satellite; STS-34 in 1989 deployed the Galileo spacecraft to explore Jupiter; and STS-43 in 1991 deployed the fifth Tracking and Data Relay Satellite (TDRS-E). Her fourth shuttle mission, STS-58 in 1993, focused on medical experiments and engineering tests.

Lucid traveled aboard Atlantis on STS-76 in March 1996 to the Russian Mir space station. She performed numerous life science and physical science experiments during the course of her stay. She returned from the station aboard Atlantis on STS-79 in September 1996.

In 2002, Lucid served as NASA's chief scientist at the agency's headquarters in Washington. She returned to Johnson in the fall of 2003 and resumed technical assignments in the Astronaut Office. She served as a Capcom in the Mission Control Center for numerous space shuttle and space station crews, representing the flight crew office and providing a friendly voice for dozens of friends and colleagues in space.

For Lucid's complete biography, visit: http://www.jsc.nasa.gov/Bios/htmlbios/lucid.html

Image, Text, Credit: NASA.

Greetings, Orbiter.ch

NASA's THEMIS Satellite Sees a Great Electron Escape










NASA - THEMIS Mission patch.

Jan. 31, 2012

video

Video above: From October to December 2003, the radiation belts swelled and shrank in response to geomagnetic storms as particles entered and escaped the belts. Credit: NASA / Goddard Scientific Visualization Studio.

When scientists discovered two great swaths of radiation encircling Earth in the 1950s, it spawned over-the-top fears about "killer electrons" and space radiation effects on Earthlings. The fears were soon quieted: the radiation doesn't reach Earth, though it can affect satellites and humans moving through the belts. Nevertheless, many mysteries about the belts – now known as the Van Allen Radiation belts – remain to this day.

Filled with electrons and energetic charged particles, the radiation belts swell and shrink in response to incoming solar energy, but no one is quite sure how. Indeed, what appears to be the same type of incoming energy has been known to cause entirely different responses on different occasions, causing increased particles in one case and particle loss in another. Theories on just what causes the belts to swell or shrink abound, with little hard evidence to distinguish between them. One big question has simply been to determine if, when the belts shrink, particles escape up and out into interplanetary space or down toward Earth. Now, a new study using multiple spacecraft simultaneously has tracked the particles and determined the escape direction for at least one event: up.

"For a long time, it was thought particles would precipitate downward out of the belts," says Drew Turner, a scientist at the University of California, Los Angeles, and first author on a paper on these results appearing onine in Nature Physics on January 29, 2012 date. "But more recently, researchers theorized that maybe particles could sweep outward. Our results for this event are clear: we saw no increase in downward precipitation."

While it may sound like a simple detail, such knowledge is not just esoteric. Indeed, the study of particle losses in the belts has so far provided more mystery and potential theories than concrete information. But understanding the radiation belts – and how they change as particles and energy come in or go out -- is a crucial part of protecting satellites that fly through the region.

The Van Allen belts fit into a larger system that stretches from the sun to Earth. The sun sends out a constant stream of solar wind, not to mention occasional much larger bursts – such as explosions from the sun's atmosphere called coronal mass ejections (CMEs) or shock fronts caused by fast solar winds overtaking slower winds called corotating interaction regions (CIRs).

When these bursts of energy move toward Earth, they can disturb Earth's own magnetic environment, known as the magnetosphere, and create a geomagnetic storm. Sometimes these storms can cause a sudden drop in the radiation belt particles, seemingly emptying the belt in only a few hours. This "drop out" can last for days. What causes the drop out, why it lasts so long, and just how the particles even leave remain unanswered questions.


Artist concept of the twin Radiation Belt Storm Probes spacecraft, scheduled for launch in August 2012. Credit: NASA.

Solving such a mystery requires numerous spacecraft measuring changes at several points in space to determine whether an event in one place affects an event elsewhere. The Radiation Belt Storm Probes (RBSP), scheduled to launch in August 2012, are specifically geared for such observations, but in the meantime, a team of scientists have brought together two disparate sets of a spacecraft to get an early multipoint view of the radiation belts during an event when the belts experienced a sudden loss of particles.

"We are entering an era where multi-spacecraft are key," says Vassilis Angelopoulos, a space scientist at UCLA, and the principal investigator for THEMIS and a coauthor on the paper. "Being able to unite a fleet of available resources into one study is becoming more of a necessity to turn a corner in our understanding of Earth's environment."

In this case, the team observed a small geomagnetic storm on January 6, 2011 using the three NASA THEMIS (Time History of Events and Macroscale Interactions during Substorms) spacecraft, two GOES (Geostationary Operational Environment Satellite), operated by the National Oceanic and Atmospheric Administration (NOAA), and six POES (Polar Operational Environmental Satellite), run jointly by NOAA, and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) spacecraft.

THEMIS

GOES

POES

Images above: By harnessing the observation abilities of the three THEMIS (top), two GOES (middle), and six POES (bottom) spacecraft, researchers could observe events in the Van Allen radiation belts from numerous viewpoints simultaneously. Credit: NASA / Goddard Space Flight Center.

The THEMIS and GOES spacecraft orbit around Earth's equatorial region, while the POES spacecraft orbit at lower altitude near the poles and travel through the radiation belts several times per day. All are equipped to study the energetic particles in the region. The observations provided an unprecedented view of a geomagnetic storm from numerous viewpoints simultaneously – and the team found unequivocally that particles escaped the radiation belts by streaming out into space, not by raining down toward Earth.

During this storm, electrons moving near the speed of light dropped out for over six hours. In that time period POES saw no increase in electrons escaping downward from the belts. On the other hand, the spacecraft did monitor a low-density patch of the belt that first appeared at the outer edges of the belts and then moved inward. This sequence is consistent with the notion that particles were streaming outward, just as the low density region of cars leaving from the front of a traffic jam moves backward over time as more and more cars are able to move forward and escape.

"This was a very simple storm," says Turner. "It's not an extreme case, so we think it's probably pretty typical of what happens in general and ongoing results from concurrent statistical studies support this."

If, indeed, electrons usually escape the radiation belts by streaming outward, it seems likely that some kind of waves aid and abet their outward motion, enabling them to reach the outer escape boundary. Hammering out this escape mechanism will be one of the jobs for RBSP, says David Sibeck at NASA's Goddard Space Flight Center in Greenbelt, Md., who is NASA's mission scientist for RBSP and project scientist for THEMIS.

"This kind of research is a key to understanding, and eventually predicting, hazardous events in the Earth’s radiation belts," says Sibeck. "It's a great comprehensive example of what we can expect to see throughout the forthcoming RBSP mission."

For more information about the associated missions, visit:

    › THEMIS mission site: http://www.nasa.gov/themis

    › GOES and POES mission site: http://goespoes.gsfc.nasa.gov/

    › RBSP mission site: http://www.nasa.gov/rbsp


Video (mentioned), Images (mentioned), Text, Credit: NASA / Goddard Space Flight Center / Karen C. Fox.

Greetings, Orbiter.ch

lundi 30 janvier 2012

New Ideas Sharpen Focus for Greener Aircraft








Aerospace engineering.

Jan. 30, 2012

Leaner, greener flying machines for the year 2025 are on the drawing boards of three industry teams under contract to the NASA Aeronautics Research Mission Directorate's Environmentally Responsible Aviation Project.


Three proposed aircraft designs have varying levels of success in meeting tough NASA goals for reducing fuel use, emissions and noise all at the same time. Image credit: NASA.

Teams from The Boeing Company in Huntington Beach, Calif., Lockheed Martin in Palmdale, Calif., and Northrop Grumman in El Segundo, Calif., have spent the last year studying how to meet NASA goals to develop technology that would allow future aircraft to burn 50 percent less fuel than aircraft that entered service in 1998 (the baseline for the study), with 75 percent fewer harmful emissions; and to shrink the size of geographic areas affected by objectionable airport noise by 83 percent.

"The real challenge is we want to accomplish all these things simultaneously," said ERA project manager Fay Collier. "It's never been done before. We looked at some very difficult metrics and tried to push all those metrics down at the same time."


The Boeing Company's advanced design concept is a variation on the extremely aerodynamic hybrid wing body. Image credit: NASA / Boeing.

So NASA put that challenge to industry – awarding a little less than $11 million to the three teams to assess what kinds of aircraft designs and technologies could help meet the goals. The companies have just given NASA their results.

"We'll be digesting the three studies and we'll be looking into what to do next," said Collier.

Boeing's advanced vehicle concept centers around the company's now familiar blended wing body design as seen in the sub-scale remotely piloted X-48, which has been wind tunnel tested at NASA's Langley Research Center and flown at NASA's Dryden Flight Research Center. One thing that makes this concept different from current airplanes is the placement of its Pratt & Whitney geared turbofan engines. The engines are on top of the plane's back end, flanked by two vertical tails to shield people on the ground from engine noise. The aircraft also would feature an advanced lightweight, damage tolerant, composite structure; technologies for reducing airframe noise; advanced flight controls; hybrid laminar flow control, which means surfaces designed to reduce drag; and long-span wings which improve fuel efficiency.


Lockheed Martin's concept uses a box wing design and other advanced technologies to achieve green aviation goals. Image credit: NASA / Lockheed Martin.

Lockheed Martin took an entirely different approach. Its engineers proposed a box wing design, in which a front wing mounted on the lower belly of the plane is joined at the tips to an aft wing mounted on top of the plane. The company has studied the box wing concept for three decades, but has been waiting for lightweight composite materials, landing gear technologies, hybrid laminar flow and other tools to make it a viable configuration. Lockheed's proposal combines the unique design with a Rolls Royce Liberty Works Ultra Fan Engine. This engine has a bypass ratio that is approximately five times greater than current engines, pushing the limits of turbofan technology.

Northrop Grumman chose to embrace a little of its company's history, going back to the 1930s and '40s, with its advanced vehicle concept. Its design is a flying wing, championed by Northrop founder Jack Northrop, and reminiscent of its B-2 aircraft. Four high-bypass engines, provided by Rolls Royce and embedded in the upper surface of the aerodynamically efficient wing would provide noise shielding. The company's expertise in building planes without the benefit of a stabilizing tail would be transferred to the commercial airline market. The Northrop proposal also incorporates advanced composite materials and engine and swept wing laminar flow control technologies.

What the studies revealed is that NASA's goals to reduce fuel consumption, emissions and noise are indeed challenging. The preliminary designs all met the pollution goal of eliminating landing and takeoff emissions of nitrogen oxides by 50 percent. All still have a little way to go to meet the other two challenges. All the designs were very close to a 50-percent fuel burn reduction, but noise reduction capabilities varied.


Northrop Grumman's concept is based on the extremely aerodynamic "flying wing" design. Image credit: NASA / Northrop Grumman.

"All of the teams have done really great work during this conceptual design study,” say Mark Mangelsdorf, ERA Project chief engineer. “Their results make me excited about how interesting and different the airplanes on the airport ramp could look in 20 years. Another great result of the study is that they have really helped us focus where to invest our research dollars over the next few years," he said.

NASA's ERA project officials say they believe all the goals can be met if small gains in noise and fuel consumption reduction can be achieved in addition to those projected in the industry studies. The results shed light on the technology and design hurdles airline manufacturers face in trying to design lean, green flying machines and will help guide NASA's environmentally responsible aviation investment strategy for the second half of its six-year project.

View Image Gallery: http://www.nasa.gov/topics/aeronautics/features/future_airplanes_index.html

Images (mentioned), Text, Credit; NASA Langley Research Center / Kathy Barnstorff.

Greetings, Orbiter.ch