vendredi 25 janvier 2013

Thawing 'Dry Ice' Drives Groovy Action on Mars












NASA - Mars Reconnaissance Orbiter (MRO) patch.

Jan. 25, 2013


Video above: Mars Reconnaissance Orbiter captures the springtime thaw of seasonal carbon dioxide ice on Mars.

Researchers using NASA's Mars Reconnaissance Orbiter see seasonal changes on far-northern Martian sand dunes caused by warming of a winter blanket of frozen carbon dioxide.

Earth has no naturally frozen carbon dioxide, though pieces of manufactured carbon-dioxide ice, called "dry ice," sublime directly from solid to gas on Earth, just as the vast blankets of dry ice do on Mars. A driving factor in the springtime changes where seasonal coverings of dry ice form on Mars is that thawing occurs at the underside of the ice sheet, where it is in contact with dark ground being warmed by early-spring sunshine through translucent ice. The trapped gas builds up pressure and breaks out in various ways.

Transient grooves form on dunes when gas trapped under the ice blanket finds an escape point and whooshes out, carrying out sand with it. The expelled sand forms dark fans or streaks on top of the ice layer at first, but this evidence disappears with the seasonal ice, and summer winds erase most of the grooves in the dunes before the next winter. The grooves are smaller features than the gullies that earlier research linked to carbon-dioxide sublimation on steeper dune slopes.


Image above: The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter snapped this series of false-color pictures of sand dunes in the north polar region of Mars. Image credit: NASA/JPL-Caltech/Univ. of Arizona.

Similar activity has been documented and explained previously where seasonal sheets of frozen carbon dioxide form and thaw near Mars' south pole. Details of the different northern seasonal changes are newly reported in a set of three papers for the journal Icarus. A video showing some of the changes is online at http://www.nasa.gov/multimedia/videogallery/index.html?media_id=158896871 .

The findings reinforce growing appreciation that Mars today, however different from its former self, is still a dynamic world, and however similar to Earth in some respects, displays some quite unearthly processes.

"It's an amazingly dynamic process," said Candice Hansen of the Planetary Science Institute, Tucson. She is lead author of the first of the three new reports. "We had this old paradigm that all the action on Mars was billions of years ago. Thanks to the ability to monitor changes with the Mars Reconnaissance Orbiter, one of the new paradigms is that Mars has many active processes today."

With three Martian years (six Earth years) of data in hand from the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE) camera, the researchers report on the sequence and variety of seasonal changes. The spring changes include outbursts of gas carrying sand, polygonal cracking of the winter ice blanketing the dunes, sandfalls down the faces of the dunes, and dark fans of sand propelled out onto the ice.

Mars Reconnaissance Orbiter (MRO). Image credit: NASA/JPL-Caltech

"It is a challenge to catch when and how those changes happen, they are so fast," said Ganna Portyankina of the University of Bern in Switzerland, lead author of the second report. "That's why only now we start to see the bigger picture that both hemispheres actually tell us similar stories."

The process of outrushing gas that carves grooves into the northern dunes resembles the process creating spider-shaped features in far southern Mars, as seen in an image at http://photojournal.jpl.nasa.gov/catalog/PIA12249, but the spiders have not been seen in the north. The seasonal dry-ice sheets overlie different types of terrain in the two hemispheres. In the south, diverse terrains include the flat, erodible ground where the spiders form, but in the north, a broad band of sand dunes encircles the permanent north polar ice cap.

Another difference is in brightening on parts of the ice-covered dunes. This brightening in the north results from the presence of water-ice frost, while in the south, similar brightening is caused by fresh carbon dioxide. The third paper of the Icarus set, by Antoine Pommerol of the University of Bern and co-authors, reports distribution of the water frost using the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). The light water frost is blown around by spring winds.

The University of Arizona, Tucson, operates the HiRISE camera, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., provided and operates CRISM. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems, Denver, built the orbiter. For more about the mission, visit: http://www.nasa.gov/mro .

A slide show of Martian icy scenes is online at: http://1.usa.gov/ZoAO8I .

Images (mentioned), Video, Text, Credits: NASA / Dwayne Brown / JPL / Guy Webster / Planetary Science Institute / Alan Fischer.

Cheers, Orbiter.ch

Mars Rover Curiosity Uses Arm Camera at Night












NASA - Mars Science Laboratory (MSL) patch.

Jan. 25, 2013


This image of a Martian rock illuminated by white-light LEDs (light emitting diodes) is part of the first set of nighttime images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the robotic arm of NASA's Mars rover Curiosity. Image credit: NASA/JPL-Caltech/MSSS.

NASA's Mars rover Curiosity has for the first time used the camera on its arm to take photos at night, illuminated by white lights and ultraviolet lights on the instrument.

Scientists used the rover's Mars Hand Lens Imager (MAHLI) instrument for a close-up nighttime look at a rock target called "Sayunei," in an area where Curiosity's front-left wheel had scuffed the rock to provide fresh, dust-free materials to examine. The site is near where the rover team plans to begin using Curiosity to drill into a rock in coming weeks. The images of the rock Sayunei and of MAHLI's calibration target were taken on Jan. 22 (PST) and received on Earth Jan. 23.


This image of a Martian rock illuminated by ultraviolet LEDs (light emitting diodes) is part of the first set of nighttime images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the robotic arm of NASA's Mars rover Curiosity. Image credit: NASA/JPL-Caltech/MSSS.

The MAHLI, an adjustable-focus color camera, includes its own LED (light-emitting diode) illumination sources. Images of Sayunei taken with white-LED illumination and with illumination by ultraviolet LEDs are available online at: http://www.nasa.gov/mission_pages/msl/multimedia/pia16711.html and http://www.nasa.gov/mission_pages/msl/multimedia/pia16712.html .

"The purpose of acquiring observations under ultraviolet illumination was to look for fluorescent minerals," said MAHLI Principal Investigator Ken Edgett of Malin Space Science Systems, San Diego. "These data just arrived this morning. The science team is still assessing the observations. If something looked green, yellow, orange or red under the ultraviolet illumination, that'd be a more clear-cut indicator of fluorescence."


This image of a calibration target illuminated by ultraviolet LEDs (light emitting diodes) is part of the first set of nighttime images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the robotic arm of NASA's Mars rover Curiosity. Image credit: NASA/JPL-Caltech/MSSS.


This image of a calibration target illuminated by white-light LEDs (light emitting diodes) is part of the first set of nighttime images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the robotic arm of NASA's Mars rover Curiosity. The set includes images of the MAHLI calibration target and of a Martian rock target called "Sayunei." MAHLI took the images on Jan. 22, 2012 (PST), after dark on the 165th Martian day, or sol, of the rover's work on Mars.

For scale, the Lincoln penny on the MAHLI calibration target is three-fourths inch (19 millimeters) in diameter. The calibration target is mounted on the rover. This image was taken from a lens distance of 3.9 inches (10 centimeters). The illumination was MAHLI's four white-light LEDs. The reflection of one pair of LEDs is seen near the center of the image. The other pair is toward the center-left and is less visible because the surface there is less reflective. Image credit: NASA/JPL-Caltech/MSSS.

Mars Science Laboratory (MSL) "Curiosity". Image credit: NASA/JPL-Caltech

NASA's Mars Science Laboratory project is using Curiosity to investigate whether the study area within Gale Crater has offered environmental conditions favorable for microbial life. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory mission for the NASA Science Mission Directorate, Washington. For more information about the mission, visit http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl .

Follow the mission on Facebook at http://www.facebook.com/marscuriosity and on Twitter at http://www.twitter.com/marscuriosity .

Images (mentioned), Text, Credits: NASA / JPL / Guy Webster.

Best regards, Orbiter.ch

jeudi 24 janvier 2013

Moons at Work












NASA / ESA - Cassini Mission to Saturn patch.

Jan. 24, 2013


The ring-region Saturnian moons Prometheus and Pan are both caught "herding" their respective rings in this image. Through their gravitational disturbances of nearby ring particles, one moon maintains a gap in the outer A ring and the other helps keep a ring narrowly confined.

Prometheus (53 miles, or 86 kilometers across), together with Pandora (not seen in this image), maintains the narrow F ring seen at the bottom left in this image. Pan (17 miles, or 28 kilometers across) holds open the Encke gap in which it finds itself embedded in the center. The bright dot near the inner edge of the Encke gap is a background star.

This view looks toward the unilluminated side of the rings from about 29 degrees below the ringplane. The image was taken in visible violet light with the Cassini spacecraft narrow-angle camera on Sept. 18, 2012.

The view was acquired at a distance of approximately 1.4 million miles (2.3 million kilometers) from Pan and at a Sun-Pan-spacecraft, or phase, angle of 98 degrees. Image scale is 9 miles (14 kilometers) per pixel.

Cassini spacecraft

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about Cassini Mission, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov and http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images, Text, Credits: NASA / ESA / JPL-Caltech / Space Science Institute.

Greetings, Orbiter.ch

Choice of a new fighter aircraft of the Swiss Air Force: Description and comparison












Swiss Air Force logo.

Jan. 24, 2013

Is the avalanche (Switzerland is an alpine country after all) of critical reviews of the Gripen and Dassault aircrafts justified?

Here is a comparative description of the two aircrafts remaining in the "race", although officially, according to the Minister of Defense, "the die have been rolled", the matter is still being discussed at Federal Governement level. And it is likely that the Swiss people (through direct democracy) will have the final vote as to which aircraft should be purchased or not.

Dassault Rafale

Rafale jet fighter

The Dassault Rafale is a French military fourth generation omnirole plane, developed and produced by French manufacturer Dassault Aviation. 126 aircrafts have recently been ordered by India.

First commissioned on 18 May 2001, commissioning of the fourth generation in 2006.
Wingspan: 11 m
Length: 15 m
Engine: two-reactor Snecma M88-2
Manufacturer: Dassault Aviation

Weapons for the Rafale

Saab JAS 39 Gripen

Saab Gripen C/D jet fighter

The JAS 39 Gripen ("Griffon") is a military fourth generation multirole aircraft developed by Sweden in the 1980s.

Commissioned in 1996 by the Swedish Air Force, it has so far been exported to Hungary, Czech Republic, South Africa and Thailand with over 240 total aircrafts ordered. The model Gripen E / F pre-ordered by Switzerland does not yet exist.
Wingspan: 8.41 m
Length: 14 m
Engine type: single General Electric F404 reactor
Manufacturer: Saab

Weapons for the Gripen

The list of specifications issued by the Swiss government to builders breaks down to the following key points:

- Maximum budget of CHF 3.126 billion.

- Costs per flight hour (operational costs of the aircraft) up to CHF 10,000.-/hour.

- Speed ​​limit threshold at Mach 1.5 (1800km/hour).

- Multi-role aircraft, weapons and fourth generation onboard technology (laser guidance pod, HUD with flight weapons information, latest generation state-of-the-art, radar, etc.).

- Assembly in Switzerland and had complete control over operation and maintenance.

- Payment by installments (upon delivery).

In Emmen (AB), whilst presenting the 2012 Swiss weapons program, Armasuisse (Swiss arsenals management facilities) in cooperation with the Swiss Military Department and the aircraft builders, performed validation tests of both airplanes for over several days and sessions, including two for the Gripen only.

The Rafale during flight tests, escorted by two FA-18 Swiss Air Force

Here are the test results and assessment of the specifications for both planes:

The Gripen has already largely exceeded the planned budget: the invoice will be CHF 3.346 billion. More importantly, the operating costs of the machine will be significantly higher than CHF 10,000.- per flight hour, as indicated by the manufacturer, Saab, when the aircraft was first presented. According to the Swiss government's call for tender, the operating costs of 22 new units amount to 102 million Swiss francs per year.

Taking into account staff costs (24 million francs), maintenance (51 million), and fuel (21 million) as described, and 180 hours of annual flight by aircraft, the hourly operating cost for the "Gripen E" will exceed 24,000.- francs.

During the presentation of the Gripen, Saab produced a maintenance plan that only takes fuel costs into account, while Dassault takes all costs into account (maintenance, spare parts, personnel, fuel). So for a 4th generation fighter, the Rafale's average operating costs, about CHF 20,000.-/hour.

 Gripen during flight tests, escorted by a FA-18 Swiss Air Force

Regarding the speed limit imposed in the specifications requirements by the Swiss government (Mach-1, 5 or 1800km/h), the Gripen painfully reached Mach-1,34 (the pilot must have been "standing" on the throttle), while the Rafale effortlessly reached Mach-2.

Unlike the conditions laid down in the tender submitted in 2007/2008 to various manufacturers, the new Gripen might finally not even be assembled in Switzerland. In its statement, the Swiss government (Federal Council) noted that, upon evaluation, the idea of an assembly in Switzerland was deemed economically not defendable, and was discarded.

Instead, a team of Ruag and Swiss Air Force would be sent to Sweden to participate in the mounting of the aircrafts and acquire the necessary know-how.

In addition to that amount, you have to add 220 million francs for a five-year rental of a fleet of 11 'Gripen C/D", as the Gripen E/F model is still in its design stage. With everything included, the final bill might well reach CHF 3.346 billion.

Saab can offer a first delivery of three copies of the old improved Gripen model, as well as the delivery of the new model (yet to be built) by 2018 at the earliest.

Northrop F-5E Tiger II Swiss Air Force

Image above: The choice of this new combat aircraft designed to replace the F-5 Tiger E become technologically and generational obsolete.

Besides, the testing phase represents the most problematic part of any new aircraft model development, along with all the defects found during testing. In this scenario, Switzerland would become a partner for Sweden and would participate in the development of the aircraft, with all the additional financial risks inherent to developing and constructing such a fighter. For the moment, the only experience Switzerland possesses in aircraft manufacturing breaks down to Pilatus aircrafts with single engine propellers.

Dassault has accepted payment by installments and has the ability to rapidly deliver an omni-role fighter (with more operational capabilities than multi-role fighters). The Rafale is in perfect working condition and its technology is being constantly improved, e.g. with a latest generation "SAR"-type embarked radar, while Saab plans to introduce "RAVEN"-type radars, which is not yet fully developed.

The Rafale has a range of operational flight of 1 hour and 20 minutes, against 30 minutes for the Gripen (with its ventral fuel tank). Therefore it takes three Gripen to do the job of one Rafale. Which triples the hour flight cost of a Gripen.

 Comparative table of proportions fighter jets 4th Generation

Finally, given Switzerland's current fiscal challenges with several countries, it would highly advisable for the country to negotiate, with the government concerned, a fiscal agreement right next to the aircraft purchase contract. From a "bad contributor", Switzerland would turn into a great customer for another thirty years, bearing in mind that thirty years is what it takes for a country to pay off a fighter aircraft.

Related links:

SAAB Group website - (In German) Gripen und die Schweiz, die ideale partnerschaft:
http://www.saabgroup.com/de/Air/Gripen-Fighter-System/Gripen-fuer-die-Schweiz/?gclid=CI-p56uI_bQCFUmN3godTkcAvw

SAAB Group site web - (In French) Le Gripen et la Suisse, le partenariat idéal:
http://www.saabgroup.com/fr/Air/Gripen-Fighter-System/Le-Gripen-pour-la-Suisse/

Dassault Aviation Group website: http://www.dassault-aviation.com/

Images, Text, Credits: Saab / Dassault Aviation / Swiss Army / KGM Aviation / Orbiter.ch Aerospace.

N.B.: The Swiss Air Force and Swiss Army is mentioned for images sources, this article is completely independent of the governments and their institutions.

Best regards, Orbiter.ch

mercredi 23 janvier 2013

'Hi-C' Mission Sees Energy in the Sun's Corona












NASA patch.

Jan. 23, 2013

The optics engineering expertise at the NASA's Marshall Space Flight Center in Huntsville, Ala., made it possible for a group of solar scientist to see into the sun's corona in unprecedented detail. The final mirror configuration was completed with inputs from partners at the Smithsonian Astrophysical Observatory, or SAO, in Cambridge, Mass., and a new manufacturing technique developed in coordination with L-3Com/Tinsley Laboratories of Richmond, Calif.

The High Resolution Coronal Imager, or Hi-C, captured the highest-resolution images ever taken of the million-degree solar corona using a resolution five times higher than previous imagers. The corona is hotter than the solar surface and is the location where solar flares occur and energy is released that drive solar storms that can impact Earth.


Image above: The Hi-C instrument on the integration table at the Harvard-Smithsonian Center for Astrophysics. (NASA/MSFC).

Weighing 464 pounds, the 6-foot-long Hi-C telescope took 165 images during its brief 620-second sounding rocket flight July 11. The telescope focused on a large active region on the sun, with some images revealing the dynamic structure of the solar atmosphere in fine detail. When combined with the full sun images from NASA’s Solar Dynamics Observatory, SDO, a new picture of the solar corona is now emerging.

Hi-C's mirrors are approximately 9.5 inches across, roughly the same size as the SDO, instrument’s mirrors. However, due to a set of innovations on Hi-C's optics array, the nimble telescope was able to peer deeper into the sun's corona in the extreme ultraviolet wavelength.


Image above: The Hi C payload and the subsystems rest on the desert after parachuting back to Earth. (NASA/MSFC).

"These mirrors were to be the finest pieces of glass ever fabricated for solar astrophysics," said Marshall heliophysicist Dr. Jonathan Cirtain, principal investigator on the Hi-C mission. "We had never attempted such a program before and had to develop new techniques for grinding the optics and polishing the surfaces, not to mention figuring out how to mount them without diminishing the performance. The final mirror surface is so smooth that it only deviates from being perfectly smooth by a few angstroms over the 24 cm optic."

Using these quality optics, images were acquired at a rate of approximately one every five seconds and provided proof of a long-standing theory to explain solar coronal dynamics.


Image above: The recovering team poses for a photo with the payload before loading the instrument in a pair of U.S. Army Helicopters and returning to base. (NASA/MSFC).

The optical design was provided by scientists and engineers from Marshall’s Science and Technology Office as well as SAO personnel. "Dr. Cirtain asked us to develop the mirrors initially to see how well we could make them," said John Calhoun, Lead for Optics at Marshall. "The initial specifications were only a goal; however, we made such excellent progress on them that Dr. Cirtain was able to get the funding for his flight demonstration. Credit belongs to the superb work performed by our senior opticians, although their initial response to the very challenging fabrication was to refer to the optics as the “oh, my god” mirrors."

Watch a video of Hi-C's observations of the sun:

Hi-C and AIA View the Sun

Scientists at Lededev Physical Institute in Moscow, Russia developed the filters for the instrument front aperture plate. These whisper thin filters reject the unwanted wavelengths of light and only transmit the extreme ultraviolet spectrum.

The high-quality optics were aligned with extreme accuracy. Mounting of the mirrors in the telescope was done using a new method that significantly reduced the impact of the process on the shape of the mirrors. Scientists and engineers from SAO, along with Marshall and the University of Alabama in Huntsville, worked to complete alignment of the mirrors, maintaining optic spacing to within a few ten-thousandths of an inch. This innovative approach to aligning and installing the mirrors then had to be maintained so the instrument could survive the harsh vibration and thermal conditions during launch and flight of the rocket.

Scientists have worked for the better part of a decade designing and building test facilities, followed by development, fabrication and testing of the optics.

"This flight represents the culmination of thirty-years of effort to develop these exceptionally high quality optics," said Co-investigator Dr. Leon Golub of SAO.

Marshall scientists and engineers also partnered with engineers from the University of Central Lancashire and Apogee Imaging Systems in Richmond, CA to develop a large format camera detector (16 megapixel) with a high speed image readout. The combination of the optics, the telescope and the camera system combined to deliver the highest cadence and highest resolution image set yet collected for the solar million degree atmosphere.

"As for the findings from Hi-C, the most important implication to me is the realization that at 150 km spatial resolution and an image cadence of five seconds, solar astrophysics can make multiple major advances in the science of how stars work and evolve," said Cirtain. "That, I find, is breathtaking, especially for a sounding rocket to discover."

Partners associated with the development of the Hi-C telescope also include Lockheed Martin's Solar Astrophysical Laboratory in Palo Alto, Calif.; the University of Central Lancashire in Lancashire, England; the Lebedev Physical Institute of the Russian Academy of Sciences in Moscow; and the Southwest Research Institute in Boulder, Colo.

Images (mentioned), Text, Credits:: NASA / Marshall Space Flight Center / Janet Anderson.

Best regards, Orbiter.ch

Protons smash lead ions in first LHC collisions of 2013












CERN - European Organization for Nuclear Research logo.

Jan. 23, 2013

The LHC accelerator team declared "stable beams" yesterday as lead ions collided with protons in the first LHC physics beams of 2013.


Image above: The first proton-lead collisions of 2013 send showers of particles through the ALICE detector (Image: CERN).

At 3.08pm yesterday, after a week of tests with beams of protons and lead ions, the Large Hadron Collider (LHC) team declared "stable beams" as protons collided with lead ions in the first LHC physics beams of 2013.

"The declaration of stable beams for collisions at a new energy, or with new particles colliding, always produces a feeling of elation as a new physics domain is opened up for exploration," says accelerator physicist John Jowett of the LHC’s heavy-ion team. "In this case, the boost in energy with respect to previous collisions of a similar type is a factor of 25 – one of the largest such gains in the history of particle accelerators. It’s wonderful that many young physicists and engineers who made vital contributions can experience this at the LHC."

Reyes Alemany Fernández of the LHC operations group says the declaration of stable beams feels likes a welcome break in a difficult journey."But there are challenges ahead," she says. 

To maximize the collision rate in more experiments than ever before, Jorg Wenninger of the LHC operations group led the commissioning of a new “squeeze”, the 15-minute phase at 4 TeV that focuses the beams down to a size of about 25 micrometres at the interaction points.

The counter-rotating beams of protons and lead ions started in the LHC on centred orbits with different revolution frequencies, and were ramped separately to the accelerator's maximum collision energy. "Before physics the two beams are locked to a common frequency, then gently rotated to achieve encounters in the centre of the detectors," says Philippe Baudrenghien of the Radiofrequency group. "This 'cogging' mechanism is unique to the proton-ion operation.” The resulting collisions sent showers of particles through the detectors ATLAS, CMS, LHCb and ALICE.

Setting up the proton and lead-ion beams after the end-of-year technical stop went smoothly, says Jowett, thanks to the dedication of the teams working on the injectors. "The Linac 3 team kept the lead source running throughout the technical stop and recovery of the accelerator complex was rapid," he says. "The new proton and lead beams were soon ready in their parallel chains of injectors, with a bunch filling pattern that ensures they will match up in the LHC.  The LEIR machine even attained a new ion-beam intensity record."

The collisions mark the start of a lead-proton run that is set to continue until February, when the LHC begins its two-year shutdown.

Large Hadron Collider (LHC): http://home.web.cern.ch/about/accelerators/large-hadron-collider

ALICE scrutinizes lead-proton run for quark-gluon plasma


Image above: Protons collide with lead ions in the ALICE dectector in the first LHC physics beams of 2013 (Image: CERN).

ALICE, a specialized heavy-ion detector on the LHC, will be watching the lead-proton collisions closely to tease out the effects of lead ions from the effects of quark-gluon plasma. The LHC experiments ATLAS, CMS and LHCb are also taking data.

On Sunday afternoon the control team for the Large Hadron Collider (LHC) brought protons into collision with lead ions for the LHC's first physics beams of 2013. The collisions were the first in a lead-proton run that is set to continue until February, when the LHC begins its two-year shutdown.

The LHC experiments ALICE, ATLAS, CMS and LHCb are all still taking data. ALICE is specialized in scrutinizing heavy-ion collisions to investigate the properties of the elusive quark-gluon plasma, the primordial state of matter that existed in the first moments after the big bang, just before the phase transition to matter made of nucleons (protons and neutrons).


Proton collisions with lead ions in the ALICE detector. Photo taken at the trial run of September 2012 (Image: CERN)

The LHC usually collides protons or lead ions. To study quark-gluon plasma, physicists need to create the high-temperature matter that is formed in the collisions of heavy ions. In lead-lead collisions ALICE physicists can deduce some properties of the plasma - from its effect on particles moving through it, for instance. But they also need to distinguish effects caused by the hot plasma from effects caused by the cold nuclear matter that makes up lead nuclei.

In the current run, the LHC is colliding protons with lead ions, which are made of 208 nucleons. Comparing the results of lead-proton collisions to those of lead-lead collisions will help ALICE physicists to decouple the effects of the plasma from effects that stem from having lead ions in the initial state.

"The lead-proton run will help us to understand the complexity of the lead-lead interaction at many levels," says ALICE physicist Despina Hatzifotiadou. "There is somehow a missing link in the game: We know that the configurations of the quarks and gluons that make up the protons and neutrons of the incoming lead nucleus can be somewhat different from the configurations of the quarks and gluons of the incoming protons. We want to measure if part of the effects we find when comparing lead-lead and proton-proton collisions is due to this configuration difference rather than the formation of the plasma. Proton-lead collisions, where we do not expect formation of quark-gluon plasma but we do have an incoming lead nucleus, are an ideal tool for this study."

Hatzifotiadou says the data from the lead-proton collisions will represent an ultimate benchmark to fully understand results from lead-lead collisions. "It will allow physicists to decouple the cold nuclear matter effects and thus will shed light on our study of the quark-gluon plasma," she says.

More on this story: "A bullet though an apple" – symmetry: http://www.symmetrymagazine.org/article/january-2013/a-bullet-through-an-apple

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

For more information about CERN, visit: http://public.web.cern.ch/public/Welcome.html

Images (mentioned), Text, Credit: CERN.

Greetings, Orbiter.ch

Setting the Dark on Fire












ESO - European Southern Observatory logo.

23 January 2013

 Setting the Dark on Fire

A new image from the Atacama Pathfinder Experiment (APEX) telescope in Chile shows a beautiful view of clouds of cosmic dust in the region of Orion. While these dense interstellar clouds seem dark and obscured in visible-light observations, APEX’s LABOCA camera can detect the heat glow of the dust and reveal the hiding places where new stars are being formed. But one of these dark clouds is not what it seems.

In space, dense clouds of cosmic gas and dust are the birthplaces of new stars. In visible light, this dust is dark and obscuring, hiding the stars behind it. So much so that, when astronomer William Herschel observed one such cloud in the constellation of Scorpius in 1774, he thought it was a region empty of stars and is said to have exclaimed, "Truly there is a hole in the sky here!" [1]

Reflection Nebula NGC 1999 in Orion

In order to better understand star formation, astronomers need telescopes that can observe at longer wavelengths, such as the submillimetre range, in which the dark dust grains shine rather than absorb light. APEX, on the Chajnantor Plateau in the Chilean Andes, is the largest single-dish submillimetre-wavelength telescope operating in the southern hemisphere, and is ideal for astronomers studying the birth of stars in this way.

Located in the constellation of Orion (The Hunter), 1500 light-years away from Earth, the Orion Molecular Cloud Complex is the closest region of massive star formation to Earth, and contains a treasury of bright nebulae, dark clouds and young stars. The new image shows just part of this vast complex in visible light, with the APEX observations overlaid in brilliant orange tones that seem to set the dark clouds on fire. Often, the glowing knots from APEX correspond to darker patches in visible light — the tell-tale sign of a dense cloud of dust that absorbs visible light, but glows at submillimetre wavelengths, and possibly a site of star formation.

The wide-field area around NGC 1999 in Orion

The bright patch below of the centre of the image is the nebula NGC 1999. This region — when seen in visible light — is what astronomers call a reflection nebula, where the pale blue glow of background starlight is reflected from clouds of dust. The nebula is mainly illuminated by the energetic radiation from the young star V380 Orionis [2] lurking at its heart. In the centre of the nebula is a dark patch, which can be seen even more clearly in a well-known image from the NASA/ESA Hubble Space Telescope.

Normally, a dark patch such as this would indicate a dense cloud of cosmic dust, obscuring the stars and nebula behind it. However, in this image we can see that the patch remains strikingly dark, even when the APEX observations are included. Thanks to these APEX observations, combined with infrared observations from other telescopes, astronomers believe that the patch is in fact a hole or cavity in the nebula, excavated by material flowing out of the star V380 Orionis. For once, it truly is a hole in the sky!

Setting the Dark on Fire (zoom)

The region in this image is located about two degrees south of the large and well-known Orion Nebula (Messier 42), which can be seen at the top edge of the wider view in visible light from the Digitized Sky Survey.

The APEX observations used in this image were led by Thomas Stanke (ESO), Tom Megeath (University of Toledo, USA), and Amy Stutz (Max Planck Institute for Astronomy, Heidelberg, Germany). APEX is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and ESO. Operation of APEX at Chajnantor is entrusted to ESO.

Setting the Dark on Fire (pan)

Notes:

[1] In German, "Hier ist wahrhaftig ein Loch im Himmel!"

[2] V380 Orionis has a high surface temperature of about 10 000 Kelvin (about the same in degrees Celsius), nearly twice that of our own Sun. Its mass is estimated to be 3.5 times that of the Sun.

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 ground-based astronomical observatory by far. 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 the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

The research into the dark patch in NGC 1999 discussed above is described in a paper by T. Stanke et al., A&A 518, L94 (2010) http://dx.doi.org/10.1051/0004-6361/201014612, also available as a preprint: http://arxiv.org/abs/1005.2202

Images, Text, Credits: ESO/APEX (MPIfR/ESO/OSO)/T. Stanke et al./Digitized Sky Survey 2 / Acknowledgement: Davide De Martin / IAU and Sky & Telescope / Videos: ESO/APEX (MPIfR/ESO/OSO)/T. Stanke et al./Digitized Sky Survey 2/Nick Risinger (skysurvey.org). Music: movetwo.

Greetings, Orbiter.ch

mardi 22 janvier 2013

NASA's Veteran Mars Rover Ready to Start 10th Year














NASA - Mars Exploration Rover "Opportunity" (MER-B) patch / NASA - Mars Exploration Rovers patch.

Jan. 22, 2013


As NASA's Mars Exploration Rover Opportunity neared the ninth anniversary of its landing on Mars, the rover was working in the 'Matijevic Hill' area seen in this view from Opportunity's panoramic camera (Pancam). Opportunity landed Jan. 24, 2004, PST (Jan. 25 UTC). Image credit: NASA/JPL-Caltech/Arizona State Univ.

NASA's Mars Exploration Rover Opportunity, one of the twin rovers that bounced to airbag-cushioned safe landings on Mars nine years ago this week, is currently examining veined rocks on the rim of an ancient crater.

Opportunity has driven 22.03 miles (35.46 kilometers) since it landed in the Meridiani Planum region of Mars on Jan. 24, 2004, PST (Jan. 25, Universal Time). Its original assignment was to keep working for three months, drive about 2,000 feet (600 meters) and provide the tools for researchers to investigate whether the area's environment had ever been wet. It landed in a backyard-size bowl, Eagle Crater. During those first three months, it transmitted back to Earth evidence that water long ago soaked the ground and flowed across the surface.


Opportunity's Pancam took the component images for this mosaic during the period from the mission's 3,137th Martian day, or sol, (Nov. 19, 2012) through Sol 3150 (Dec. 3, 2012). Image credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

Since then, the mission's team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., has driven Opportunity across the plains of Meridiani to successively larger craters for access to material naturally exposed from deeper, older layers of Martian history.

Opportunity has operated on Mars 36 times longer than the three months planned as its prime mission.

"What's most important is not how long it has lasted or even how far it has driven, but how much exploration and scientific discovery Opportunity has accomplished," said JPL's John Callas, manager of NASA's Mars Exploration Rover Project. The project has included both Opportunity and its twin, Spirit, which ceased operations in 2010.


This 360-degree stereo panorama assembled from images taken by the navigation camera on NASA's Mars Exporation Rover The image combines views from the left eye and right eye of the Pancam to appear three-dimensional when seen through blue-red glasses with the red lens on the left. Image credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

This month, Opportunity is using cameras on its mast and tools on its robotic arm to investigate outcrops on the rim of Endeavour Crater, 14 miles (22 kilometers) in diameter. Results from this area of the rim, called "Matijevic Hill," are providing information about a different, possibly older wet environment, less acidic than the conditions that left clues the rover found earlier in the mission.

Mars Exploration Rover "Opportunity". Image credit: NASA/JPL-Caltech

Timed with the anniversary of the landing, the rover team has prepared a color panorama of the Matijevic Hill area. The image is online at: http://www.nasa.gov/mission_pages/mer/multimedia/pia16703.html .

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for NASA's Science Mission Directorate, Washington. JPL also manages the Mars Science Laboratory Project and its rover, Curiosity.

For more information about Opportunity, visit http://www.nasa.gov/rovers and http://marsrovers.jpl.nasa.gov . You can follow the project on Twitter and on Facebook at: http://twitter.com/MarsRovers and http://www.facebook.com/mars.rovers .

Images (mentioned), Text, Credits: NASA / JPL / Guy Webster.

Greetings, Orbiter.ch

Asteroids inflame lust

Space Colonization.

Jan. 22, 2013

Asteroids potentially rich in precious metals or water as ice, stir the envy of investors in the United States

Deep Space Industries plans to introduce from 2015 a fleet of probes to explore and exploit crossing asteroids near Earth. "Use the resources in space is the only way to ensure sustainable spatial development," said the CEO of the company, David Gump.

"We discovered over 900 new asteroids passing near the Earth every year and these objects can be as important for space activities of this century that were deposits of iron ore from Minnesota for the automotive industry in Detroit twentieth century, "he says in a statement.

Deep Space Industries, FireFlies probes

Deep Space Industries begin to evaluate promising targets for mining with small spacecraft baptized 25 kilos "FireFlies" (image above) which should be launched in 2015 for missions from two to six months. Society in search of customers and investors, working with NASA and other companies and organizations to identify asteroids with the greatest potential.

Power plants on orbits

Deep Space Industries, Power plants on orbits

These probes will be economical, says Deep Space Industries: made with elements of low-cost miniaturized satellite, they will be launched at low cost launchers carrying on board already big communications satellites.

These probes will be economical, says Deep Space Industries: made with elements of low-cost miniaturized satellite, they will be launched at low cost launchers carrying on board already big communications satellites.

From 2016, the company will begin to launch probes heavier than 32 kilos, "Dragonflies" ("Dragonfly"), capable of reaching an asteroid and return to Earth samples from 27 to 68 pounds during journeys during two to four years.

Deep Space Industries, Dragonflies probe

In 10 years, Deep Space Industries plans to exploit asteroids for their metals and other materials that will build large platforms of communication to replace satellites. In the longer term, the company is betting on the deployment orbit solar power plants that feed the Earth.

Finally, the creators of Deep Space Industries rely extract platinum asteroid for use on Earth especially in control systems. Already in April 2012, a group of wealthy investors including billionaire Larry Page, Google CEO, unveiled the first company prospecting and mining asteroids, Planetary Resources.

Deep Space Industries, Micro Gravity Foundry concept

A wealth ... platinum

The extraction of wealth by these entrepreneurs have many benefits for mankind and one day generate economic activity weighing tens of billions of dollars annually. A single asteroid 500 meters long as a platinum that the entire quantity of the metal mined in the history of humanity, according to the creators of Planetary Resources.

(Editor's Note: this is a problem that mining companies do not think maybe if rare metals (Gold, Platinum etc ...) are no longer, they will lose their values ​​and risk cause a global monetary crash, it will revisit our value systems.)

Deep Space Industries, Harvestor concept

In addition, near-Earth asteroids, which contain a lot of water ice, serve "so oasis" for shipments to distant space exploration, providing the necessary water and fuel.

Of the more than 9000 asteroids identified by NASA whose orbit passes in the vicinity of Earth, more than 1,500 have access as easy as the moon, according to investors.

Planetary Resources has already developed space telescopes that will be placed in low Earth orbit by 2014 to identify promising asteroids. The company is also planning to launch small spacecraft to go explore.

Planetary Resources logo

Space telescopes that track the asteroids in search of valuable materials and water probes that are going to meet these giant rocks floating in space for mine, fueling stations to support future colonization of space ... Today it is science fiction, but can be much longer.

Indeed, January 22, 2013 a new company with the aim of achieving realize these scenarios will be announced at the Santa Monica Museum of Flying, California. Currently few details have been released but we know that this company is founded by the former president of Astrobotic Technology (a company that aims to send a rover on the moon in 2015 for the Google Lunar Xprize) and it planning to conceive it the first fleet of probes prospectrices. And this is not the first to announce such plans: April 24, 2012, the company has also unveiled Planetary Resources an ambitious program to make it the first mining company in the world.

The company was founded by Peter Diamandis and Erik Anderson, two figures of private space and is funded by several billionaires that Larry Page, one of the founders of Google. Planetary Resources Plan is to achieve operation of an asteroid through three phases. The first is to send several space telescopes in Earth orbit, the ARKYD SERIES 100 (image below), to identify interesting targets.

Planetary Resources ARKYD SERIES 100

Then, phase 2 involves sending probes ARKYD SERIES 200 or "interceptor" to fly asteroids identified and studied in detail. Finally, ARKYD SERIES 300 or "rendezvous prospector" will be sent to the chosen target to accurately determine its composition, shape, surface composition, density ... After this last step in the mining itself will begin with robots whose details have not yet been released. The first probe ARKYD SERIES 100 should be launched before 2015.

NASA Artist's concept of the asteroid retrieval

Finally, and we enter an area even closer to science fiction, NASA scientists have devised a mission would be to bring an asteroid directly into lunar orbit by capturing it with a kind of container and the propelling means of an ion thruster (image above). Once in orbit around the Moon, it would be easier to send probes to explore or even send astronauts on its surface. This mission is a hypothetical concept proposed by engineers and is not a validated project by NASA.

Related links:

Deep Space Industries: http://deepspaceindustries.com/

Planetary Resources: http://www.planetaryresources.com/

Images, Text, Credits: ATS / Deep Space Industries / Planetary Resources / NASA / Orbiter.ch Aerospace.

Best regards, Orbiter.ch

Betelgeuse Braces for a collision












ESA - Herschel Mission patch.

22 January 2013


Multiple arcs are revealed around Betelgeuse, the nearest red supergiant star to Earth, in this new image from ESA’s Herschel space observatory. The star and its arc-shaped shields could collide with an intriguing dusty ‘wall’ in 5000 years.

Betelgeuse rides on the shoulder of the constellation Orion the Hunter. It can easily be seen with the naked eye in the northern hemisphere winter night sky as the orange–red star above and to the left of Orion’s famous three-star belt.

Roughly 1000 times the diameter of our Sun and shining 100 000 times more brightly, Betelgeuse’s impressive statistics come with a cost. For this star is likely on its way to a spectacular supernova explosion, having already swelled into a red supergiant and shed a significant fraction of its outer layers.

The new far-infrared view from Herschel shows how the star’s winds are crashing against the surrounding interstellar medium, creating a bow shock as the star moves through space at speeds of around 30 km/s.

A series of broken, dusty arcs ahead of the star’s direction of motion testify to a turbulent history of mass loss.

ESA / NASA Herschel space observatory

Closer to the star itself, an inner envelope of material shows a pronounced asymmetric structure. Large convective cells in the star’s outer atmosphere have likely resulted in localised, clumpy ejections of dusty debris at different stages in the past.

An intriguing linear structure is also seen further away from the star, beyond the dusty arcs. While some earlier theories proposed that this bar was a result of material ejected during a previous stage of stellar evolution, analysis of the new image suggests that it is either a linear filament linked to the Galaxy’s magnetic field, or the edge of a nearby interstellar cloud that is being illuminated by Betelgeuse.

If the bar is a completely separate object, then taking into account the motion of Betelgeuse and its arcs and the separation between them and the bar, the outermost arc will collide with the bar in just 5000 years, with the red supergiant star itself hitting the bar roughly 12 500 years later.

Related links:

Herschel - ESA's giant infrared observatory: http://www.esa.int/Our_Activities/Space_Science/Herschel

Herschel overview: http://www.esa.int/Our_Activities/Space_Science/Herschel

Herschel Images OSHI: http://oshi.esa.int/

Herschel in depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=16

Herschel Science Centre: http://herschel.esac.esa.int/

Images, Text, Credits: ESA / Herschel / PACS / L. Decin et al.

Cheers, Orbiter.ch