vendredi 22 février 2013

NASA Deciphering the Mysterious Math of the Solar Wind




















Space weather.

Feb. 22, 2013


A constant stream of particles and electromagnetic waves streams from the sun toward Earth, which is surrounded by a protective bubble called the magnetosphere. A scientist at NASA Goddard has recently devised, for the first time, a set of equations that can help describe waves in the solar wind known as Alfven waves. Credit: European Space Agency (ESA).

Many areas of scientific research -- Earth's weather, ocean currents, the outpouring of magnetic energy from the sun -- require mapping out the large scale features of a complex system and its intricate details simultaneously.

Describing such systems accurately, relies on numerous kinds of input, beginning with observations of the system, incorporating mathematical equations to approximate those observations, running computer simulations to attempt to replicate observations, and cycling back through all the steps to refine and improve the models until they jibe with what's seen. Ultimately, the models successfully help scientists describe, and even predict, how the system works.

Understanding the sun and how the material and energy it sends out affects the solar system is crucial, since it creates a dynamic space weather system that can disrupt human technology in space such as communications and global positioning system (GPS) satellites.

GPS satellites

However, the sun and its prodigious stream of solar particles, called the solar wind, can be particularly tricky to model since as the material streams to the outer reaches of the solar system it carries along its own magnetic fields. The magnetic forces add an extra set of laws to incorporate when trying to determine what's governing the movement. Indeed, until now, equations for certain aspects of the solar wind have never been successfully devised to correlate to the observations seen by instruments in space. Now, for the first time, a scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., has created a set of the necessary equations, published in Physical Review Letters on Dec. 4, 2012.

"Since the 1970s, scientists have known that movement in the solar wind often has the characteristics of a kind of wave called an Alfvén wave," says Aaron Roberts, a space scientist at Goddard. "Imagine you have a jump rope and you wiggle one end so that it sends waves down the rope. Alfvén waves are similar, but the moving rope is a magnetic field line itself."

The Alfvén waves in this case tended to have great consistency in height -- or amplitude, which is the common term when talking about waves -- but they are random in direction. You might think of it like a jump rope twirling, always the same distance from center, but nonetheless able to be in many places in space. Another way scientists have envisioned the waves is as a "random walk on a sphere." Again, always the same distance from a given center, but with a variable placement.

Such metaphorical descriptions are based on what instruments in space have, in fact, observed when they see magnetic waves go by in the solar wind. But it turns out that the equations to describe this kind of movement -- equations necessary to advance scientific models of the entire system -- were not easily found.

"The puzzle has been to figure out why the amplitude is so constant," says Roberts. "But it's been very difficult to find equations that satisfy all the characteristics of the magnetic field."

Similar waves are, in fact, seen in light, known as polarized waves. But magnetic fields have additional constraints on what shapes and configurations are even possible. Roberts found a way to overlap numerous waves of different wavelengths in such a way that they ultimately made the variation in amplitude as small as possible.

To his surprise, the equations Roberts devised matched what was observed more closely than he'd expected. Not only did the equations show waves of constant amplitude, but they also showed occasional random jumps and sharp changes -- an unexplained feature seen in the observations themselves.

"Overlapping the waves in this way gives us a way of writing down equations that we didn't have before," says Roberts. "It also has this nice consequence that it is more realistic than we expected, since it shows discontinuities we actually see in the wind. This is important for simulations and models where we want to start with initial conditions that are as close to the observed solar wind as we can get."

Of course, having an equation doesn't yet tell us the reason why the waves in the solar wind are shaped in this way. Nonetheless, equations that describe how the waves move open the door to increasingly accurate simulations that may well help explain such causes. By alternately improving models and improving observations, scientists continue the cyclic nature of such research, until just what physical action on the sun causes these curiously-shaped Alfvén waves someday becomes clear.

Images, Text, Credits: NASA's Goddard Space Flight Center / Karen C. Fox / ESA.

Greetings, Orbiter.ch

Asteroid Impact Mission Targets Didymos







ESA logo labeled.

22 February 2013

ESA’s proposed Asteroid Impact and Deflection Assessment mission now has a target: asteroid Didymos. The recent Russian meteor and, on the same day, our planet’s close encounter with an even larger chunk of celestial debris underline the need for us to learn more about these high-speed space rocks.

For the last two years, ESA has been working with international partners on the mission concept, dubbed AIDA. Last week, research centres each side of the Atlantic agreed the spacecraft would target asteroid Didymos.

Currently under study, the mission would intercept Didymos around the time of the asteroid’s closest approach to within 11 million km of Earth in 2022.

Didymos is a ‘binary’, with two asteroids orbiting each other – one is roughly 800 m across, the other about 150 m.

ESA’s AIDA mission now has a target: asteroid Didymos

AIDA is a low-budget international effort that would send two small craft to intercept a double target. While one probe smashes into the smaller asteroid at around 6.25 km/s, the other records what happens.

One effect would be a change in the orbital ballet of the two objects. AIDA is not intended to show how we could deflect an asteroid that threatens Earth but it would be a first step.

The craft are conceived to be independent and could achieve most of their goals alone. The collider is the Double Asteroid Redirection Test, or DART, from the Johns Hopkins’ Applied Physics Laboratory in the US. ESA’s Asteroid Impact Monitor, or AIM, would survey Didymos in detail, before and after the collision.

Didymos poses no risk to our planet, but will come close enough to be observable by 1–2 m-diameter telescopes on Earth before and after the strike. AIM’s close-up view would provide ‘ground truth’ and observe the impact dynamics as well as the resulting crater, allowing ground-based observations and models to be evaluated.

Didymos with its moon

Earlier this month, ESA issued a call for scientists to propose experiments that could be carried on the mission or performed on the ground to increase its return.

“AIDA is not just an asteroid mission, it is also meant as a research platform open to all different mission users,” says Andrés Gálvez, ESA studies manager.

“The project has value in many areas,” agrees Andy Cheng, AIDA lead at Johns Hopkins’ Applied Physics Laboratory, “from applied science and exploration to asteroid resource utilisation.”

Researchers have until 15 March to express their interest. The experiment ideas can be anything that deals with hypervelocity impacts, planetary science, planetary defence, human exploration or innovation in spacecraft operations.

The energy released in the AIDA impact at several kilometres per second is similar to that of a large piece of space junk hitting a satellite. The mission would thus help to model severe spacecraft damage by space debris.

Related links:

General Studies Programme: http://www.esa.int/About_Us/GSP

SSA: http://www.esa.int/Our_Activities/Operations/Space_Situational_Awareness

Space Situational Awareness - NEO: http://www.esa.int/Our_Activities/Operations/Near-Earth_Objects_-_NEO

Observatoire de la Côte d'Azur: http://www.obs-nice.fr/

DLR (English): http://www.dlr.de/en/

John Hopkins University Applied Physics Laboratory: http://www.jhuapl.edu/

Images, Text, Credit: ESA.

Greetings, Orbiter.ch

SMOS: The Global Success Story Continues









ESA - SMOS Mission logo.

22 February 2013

ESA’s water mission is shedding new light on the meandering Gulf Stream, just one of the SMOS satellite’s numerous achievements.

video
Sea-surface salinity and currents

Launched in 2009, ESA’s Soil Moisture and Ocean Salinity satellite has been helping us to understand the water cycle.

Over the past three years it has been providing more accurate information on global soil moisture and ocean salinity.

New results unveiled today in Spain show that SMOS is now providing new insights into the movement of the Gulf Stream – one of the most intensely studied current systems.

Europe soil moisture decrease

Originating in the Caribbean and flowing towards the North Atlantic, the current plays an important role in the transfer of heat and salt, influencing the climate of North America’s east coast and Europe’s west coast.

Salinity observations from SMOS show that warm, salty water being carried north by the Gulf Stream meets the colder, less-salty water transported southward along North America’s east coast by the Labrador Current, mixing the water masses off Cape Hatteras.

SMOS can distinguish between and follow the resulting eddies that are ‘pinched off’ from the current and form little parcels of warm and salty water in the Labrador Current, and the colder, fresher water in the Gulf Stream.

SMOS in orbit

SMOS is able to monitor this process thanks to its high resolution and frequent revisits. This is giving scientists a new view of how salt is exchanged across current boundaries – a key to understanding the ‘conveyor belt’ of global oceanic circulation.

These and other scientific achievements from three years of the SMOS mission were presented at a conference held today at ESA’s European Space Astronomy Centre in Villanueva de la Cañada, near Madrid, Spain. SMOS was realised with special contributions from France and Spain.

“SMOS is the second Earth Explorer we have placed in orbit – and is delivering important new information on global soil moisture and ocean salinity for a broad range of applications,” noted Volker Liebig, ESA Director of Earth Observation Programmes.

The mission’s Lead Investigators, Yann Kerr and Jordi Font, are the focal point of the scientific research of the mission and lead discussions on soil moisture and ocean salinity findings.

Hurricane Sandy from SMOS

Unexpected results demonstrating the versatility of this collaborative European mission – like the findings on the Gulf Stream – were also highlighted at the event by Nicolas Reul from Ifremer, France’s institute for sea research.

Surpassing expectations, SMOS data are being used to monitor Arctic sea-ice extent and thickness, providing daily coverage of the Arctic Ocean.

In addition, the satellite can determine wind speeds under hurricanes – such as last year’s Hurricane Sandy that devastated parts of the US east coast – by measuring the microwave radiation emitted by rough seas.

Today’s workshop included a welcome by the head of ESA’s European Space Astronomy Centre in Spain, Álvaro Giménez, and a speech on the future of space technology in Spain by Luis Valero, Spain’s General Secretary for Industry and SMES.

Related links:

SMOS: http://www.esa.int/Our_Activities/Observing_the_Earth/SMOS

SMOS technical site: http://earth.esa.int/SMOS

ESAC: http://www.esa.int/About_Us/ESAC

ESA/AOES Medialab/CESBIO/Ifremer.

Images, Video, Text, Credits: ESA / AOES Medialab / CESBIO / Ifremer.

Best regards, Orbiter.ch

mercredi 20 février 2013

Solar Impulse will fly the United States in 2013













Solar Impulse Across America.

Feb. 20, 2013

Solar Impulse Across America

The solar airplane of Bertrand Piccard will hover for two months over the USA. This journey should take place next summer. Four steps are planned.


Researcher and aviation pioneer Bertrand Piccard Solar will fly Solar Impulse in 2013 the United States from west to east. The journey should take about two months at the speed of 70 km / h. Four steps are planned between San Francisco and New York.

A Boeing 747 landed Wednesday on the military airfield of Payerne (AB) Switzerland. He came searching for spare parts of Solar Impulse for his journey to the United States. Boeing will leave Thursday morning.

Solar Impulse loading on board a Boeing 747 in Payerne AB

The aircraft landed at 17:30. A kiss black, more than a hundred curious transistor attended the arrival of the jumbo jet company Cargolux. The device from Luxembourg is posed as a flower on the short track military.

Loading nose

His arrival was a challenge, said André Borschberg, Director of Solar Impulse. He has had to verify that the tarmac is strong enough to support this giant air.

Solar Impulse loading on board a Boeing 747 in Payerne AB

The jumbo jet has indeed the same scale as the solar airplane, or 64 meters. But it weighs 257 times more than this one: 1600 kg for Solar Impulse against 412'770 kg for 747. It is the only feasible means of transport for a camera so small and fragile, the CEO noted.

Gaping nose, the plane was loaded with the help of cranes. Main deck house hosted the HB-SIA parts. Among them, the fuselage and the wing disassembled into three parts, batteries and engine.

Solar Impulse loading on board a Boeing 747 in Payerne AB

Three accompanying

Giant airs join Moffett Airfield, on the California coast, near the center of NASA research in the heart of Silicon Valley. The Jumbo Jet arrive at its destination Thursday around 20:30 or 12:30 in the United States. It will make a stop in Luxembourg to refuel and load additional equipment.

Three engineers and technicians Solar Impulse will travel. They ensure that safety requirements are met and handling during unloading of the machine.

Presentation to the President

The plane will be reassembled in early March in anticipation of its mission "Across America". After flying from Switzerland to Morocco last year, the prototype will attempt to perform the legendary flight from the west coast to the east coast, from San Francisco to Washington DC and New York.

The plane and pilot Bertrand Piccard and André Borschberg be ready to go around May 1. The journey should be completed in New York in July, noted André Borschberg. "Our goal is to make at least four stops, not to go fast," he said.

SolarImpulse description

"The interest in this prototype is strong in the country aviation pioneer. We have contacts in Congress, with universities, with companies in Silicon Valley. We also hope to present the aircraft to President Barack Obama, "said the driver.

Find partners

The aim is not only to make the project, but also to find partners on the continent, and Asia. China in particular is very interested in these new technologies, reported André Borschberg.

The operational cost of the journey to the United States amounted to $ 2.5 million. It includes transportation and infrastructure. The million allocated to Presence Switzerland will communication activities and media, he said.

"Overall Operation Solar Impulse is expected to reach 130 million. We are still looking for 30 million ", said the aviator.

SolarImpulse across Bourget, Switzerland

The second way

The HB-SIA will return to Switzerland in early September. Its drivers to precede the end of July.

The second prototype, HB-SIB, is under construction in Dübendorf,  Switzerland. The assembly will be done soon. Should join Payerne in early 2014. Its interior and its technology should be presented in November. Then testing can begin.

"In two years starts around the world. End of March 2015 is tomorrow for us, "noted Andre Borschberg.

Fore more information about Solar Impulse, visit: http://www.solarimpulse.com/

Images, Text, Credits: SolarImpulse / ATS / Newsnet / Keystone / Translation: Orbiter.ch Aerospace.

Greetings, Orbiter.ch

NASA's SDO Observes Fast-Growing Sunspot












NASA - Solar Dynamics Observatory (SDO) patch.

Feb. 20, 2013


Image above: The bottom two black spots on the sun, known as sunspots, appeared quickly over the course of Feb. 19-20, 2013. These two sunspots are part of the same system and are over six Earths across. This image combines images from two instruments on NASA's Solar Dynamics Observatory (SDO): the Helioseismic and Magnetic Imager (HMI), which takes pictures in visible light that show sunspots and the Advanced Imaging Assembly (AIA), which took an image in the 304 Angstrom wavelength showing the lower atmosphere of the sun, which is colorized in red. Credit: NASA/SDO/AIA/HMI/Goddard Space Flight Center.

As magnetic fields on the sun rearrange and realign, dark spots known as sunspots can appear on its surface. Over the course of Feb. 19-20, 2013, scientists watched a giant sunspot form in under 48 hours. It has grown to over six Earth diameters across but its full extent is hard to judge since the spot lies on a sphere not a flat disk.

The spot quickly evolved into what's called a delta region, in which the lighter areas around the sunspot, the penumbra, exhibit magnetic fields that point in the opposite direction of those fields in the center, dark area. This is a fairly unstable configuration that scientists know can lead to eruptions of radiation on the sun called solar flares.

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NASA's SDO Shows A Little Rain On the Sun

Video above: On July 19, 2012, an eruption occurred on the sun that produced a moderately powerful solar flare and a dazzling magnetic display known as coronal rain. Hot plasma in the corona cooled and condensed along strong magnetic fields in the region. Magnetic fields, are invisible, but the charged plasma is forced to move along the lines, showing up brightly in the extreme ultraviolet wavelength of 304 Angstroms, and outlining the fields as it slowly falls back to the solar surface. Music: "Thunderbolt" by Lars Leonhard, courtesy of artist. Credit: NASA/SDO/Goddard Scientific Visualization Studio.

Eruptive events on the sun can be wildly different. Some come just with a solar flare, some with an additional ejection of solar material called a coronal mass ejection (CME), and some with complex moving structures in association with changes in magnetic field lines that loop up into the sun's atmosphere, the corona.

On July 19, 2012, an eruption occurred on the sun that produced all three. A moderately powerful solar flare exploded on the sun's lower right limb, sending out light and radiation. Next came a CME, which shot off to the right out into space. And then, the sun treated viewers to one of its dazzling magnetic displays – a phenomenon known as coronal rain.

Over the course of the next day, hot plasma in the corona cooled and condensed along strong magnetic fields in the region. Magnetic fields, themselves, are invisible, but the charged plasma is forced to move along the lines, showing up brightly in the extreme ultraviolet wavelength of 304 Angstroms, which highlights material at a temperature of about 50,000 Kelvin. This plasma acts as a tracer, helping scientists watch the dance of magnetic fields on the sun, outlining the fields as it slowly falls back to the solar surface.

Solar Dynamics Observatory (SDO). Credit: NASA

The footage in this video was collected by NASA’s Solar Dynamics Observatory's Atmospheric Imaging Assembly (AIA) instrument. SDO collected one frame every 12 seconds, and the movie plays at 30 frames per second, so each second in this video corresponds to six minutes of real time. The video covers 12:30 a.m. EDT to 10:00 p.m. EDT on July 19, 2012.

For more information about Solar Dynamics Observatory (SDO): http://www.nasa.gov/mission_pages/sdo/main/index.html

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

Greetings, Orbiter.ch

NASA's Kepler Mission Discovers Tiny Planet System












NASA - Kepler Mission patch.

Feb. 20, 2013


Image above: A Moon-size Line Up: The line up compares artist's concepts of the planets in the Kepler-37 system to the moon and planets in the solar system. The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. Kepler-37c, the second planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the third planet, is twice the size of Earth. Click image for full caption and larger size. Image credit: NASA/Ames/JPL-Caltech.

NASA's Kepler mission scientists have discovered a new planetary system that is home to the smallest planet yet found around a star similar to our sun.

The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra. The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge.

The moon-size planet and its two companion planets were found by scientists with NASA's Kepler mission to find Earth-sized planets in or near the "habitable zone," the region in a planetary system where liquid water might exist on the surface of an orbiting planet. However, while the star in Kepler-37 may be similar to our sun, the system appears quite unlike the solar system in which we live.

Astronomers think Kepler-37b does not have an atmosphere and cannot support life as we know it. The tiny planet almost certainly is rocky in composition. Kepler-37c, the closer neighboring planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the farther planet, is twice the size of Earth.

The first exoplanets found to orbit a normal star were giants. As technologies have advanced, smaller and smaller planets have been found, and Kepler has shown even Earth-size exoplanets are common.

"Even Kepler can only detect such a tiny world around the brightest stars it observes," said Jack Lissauer, a planetary scientist at NASA's Ames Research Center in Moffett Field, Calif. "The fact we've discovered tiny Kepler-37b suggests such little planets are common, and more planetary wonders await as we continue to gather and analyze additional data."


Image above: The artist's concept depicts the new planet dubbed Kepler-37b. The planet is slightly larger than our moon, measuring about one-third the size of Earth. Kepler-37b orbits its host star every 13 days at less than one-third the distance Mercury is to the sun. Click image for full caption and larger size. Image credit: NASA/Ames/JPL-Caltech.

Kepler-37's host star belongs to the same class as our sun, although it is slightly cooler and smaller. All three planets orbit the star at less than the distance Mercury is to the sun, suggesting they are very hot, inhospitable worlds. Kepler-37b orbits every 13 days at less than one-third Mercury's distance from the sun. The estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin), would be hot enough to melt the zinc in a penny. Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively.

"We uncovered a planet smaller than any in our solar system orbiting one of the few stars that is both bright and quiet, where signal detection was possible," said Thomas Barclay, Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, Calif., and lead author of the new study published in the journal Nature. "This discovery shows close-in planets can be smaller, as well as much larger, than planets orbiting our sun."

The research team used data from NASA's Kepler space telescope, which simultaneously and continuously measures the brightness of more than 150,000 stars every 30 minutes. When a planet candidate transits, or passes, in front of the star from the spacecraft's vantage point, a percentage of light from the star is blocked. This causes a dip in the brightness of the starlight that reveals the transiting planet's size relative to its star.

The size of the star must be known in order to measure the planet's size accurately. To learn more about the properties of the star Kepler-37, scientists examined sound waves generated by the boiling motion beneath the surface of the star. They probed the interior structure of Kepler-37's star just as geologists use seismic waves generated by earthquakes to probe the interior structure of Earth. The science is called asteroseismology.

The sound waves travel into the star and bring information back up to the surface. The waves cause oscillations that Kepler observes as a rapid flickering of the star's brightness. Like bells in a steeple, small stars ring at high tones while larger stars boom in lower tones. The barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure. This is why most objects previously subjected to asteroseismic analysis are larger than the sun.

Kepler Space Telescope. Image credit: NASA/Ames/JPL-Caltech

With the very high precision of the Kepler instrument, astronomers have reached a new milestone. The star Kepler-37, with a radius just three-quarters of the sun, now is the smallest bell in the asteroseismology steeple. The radius of the star is known to 3 percent accuracy, which translates to exceptional accuracy in the planet's size.

Ames is responsible for Kepler's ground system development, mission operations, and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, Calif., managed Kepler mission development.

Ball Aerospace & Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA's tenth Discovery Mission and was funded by NASA's Science Mission Directorate at the agency's headquarters in Washington.

For information about the Kepler Mission: http://www.nasa.gov/kepler

Images (mentioned), Text, Credits: NASA / Steve Cole / Ames Research Center / Michele Johnson.

Best regards, Orbiter.ch

NASA Rover Confirms First Drilled Mars Rock Sample












NASA - Mars Science Laboratory (MSL) patch.

Feb. 20, 2013


This image from NASA's Curiosity rover shows the first sample of powdered rock extracted by the rover's drill. Image credit: NASA/JPL-Caltech/MSSS.

NASA's Mars rover Curiosity has relayed new images that confirm it has successfully obtained the first sample ever collected from the interior of a rock on another planet. No rover has ever drilled into a rock beyond Earth and collected a sample from its interior.

Transfer of the powdered-rock sample into an open scoop was visible for the first time in images received Wednesday at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

video
 Drilling into Mars

This animation of NASA's Curiosity rover shows the complicated suite of operations involved in conducting the rover's first rock sample drilling on Mars and transferring the sample to the rover's scoop for inspection. The drilling and sample transfer took place on Feb. 8 and 20, 2013, or sols 182 and 193, Curiosity's 182nd and 193rd Martian days of operations. Credit: NASA/JPL-Caltech.

"Seeing the powder from the drill in the scoop allows us to verify for the first time the drill collected a sample as it bore into the rock," said JPL's Scott McCloskey, drill systems engineer for Curiosity. "Many of us have been working toward this day for years. Getting final confirmation of successful drilling is incredibly gratifying. For the sampling team, this is the equivalent of the landing team going crazy after the successful touchdown."


This image from the Mars Hand Lens Imager (MAHLI) on NASA's Mars rover Curiosity shows details of rock texture and color in an area where the rover's Dust Removal Tool (DRT) brushed away dust that was on the rock. Image credit: NASA/JPL-Caltech/MSSS/Honeybee Robotics/LANL/CNES.

The drill on Curiosity's robotic arm took in the powder as it bored a 2.5-inch (6.4-centimeter) hole into a target on flat Martian bedrock on Feb. 8. The rover team plans to have Curiosity sieve the sample and deliver portions of it to analytical instruments inside the rover.

The scoop now holding the precious sample is part of Curiosity's Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) device. During the next steps of processing, the powder will be enclosed inside CHIMRA and shaken once or twice over a sieve that screens out particles larger than 0.006 inch (150 microns) across.

Small portions of the sieved sample later will be delivered through inlet ports on top of the rover deck into the Chemistry and Mineralogy (CheMin) instrument and Sample Analysis at Mars (SAM) instrument.


This full-resolution image from NASA's Curiosity shows the turret of tools at the end of the rover's extended robotic arm on Aug. 20, 2012. Image credit: NASA/JPL-Caltech.

In response to information gained during testing at JPL, the processing and delivery plan has been adjusted to reduce use of mechanical vibration. The 150-micron screen in one of the two test versions of CHIMRA became partially detached after extensive use, although it remained usable. The team has added precautions for use of Curiosity's sampling system while continuing to study the cause and ramifications of the separation.

The sample comes from a fine-grained, veiny sedimentary rock called "John Klein," named in memory of a Mars Science Laboratory deputy project manager who died in 2011. The rock was selected for the first sample drilling because it may hold evidence of wet environmental conditions long ago. The rover's laboratory analysis of the powder may provide information about those conditions.


This image shows the location of the 150-micrometer sieve screen on NASA's Mars rover Curiosity, a device used to remove larger particles from samples before delivery to science instruments. Image credit: NASA/JPL-Caltech/MSSS.

NASA's Mars Science Laboratory Project is using the Curiosity rover with its 10 science instruments to investigate whether an area within Mars' Gale Crater ever has offered an environment favorable for microbial life. JPL, a division of the California Institute of Technology, Pasadena, manages the project for NASA's Science Mission Directorate in Washington.

An image of the drill's rock powder held in the scoop is online at: http://www.nasa.gov/mission_pages/msl/multimedia/pia16729.html.

For more about the mission, visit: http://www.nasa.gov/msl .

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

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

Greetings, Orbiter.ch

Sweeping the Dust from a Cosmic Lobster












ESO - European Southern Observatory logo.

20 February 2013

New infrared VISTA image of NGC 6357

 The Lobster Nebula seen with ESO’s VISTA telescope

A new image from ESO’s VISTA telescope captures a celestial landscape of glowing clouds of gas and tendrils of dust surrounding hot young stars. This infrared view reveals the stellar nursery known as NGC 6357 in a surprising new light. It was taken as part of a VISTA survey that is currently scanning the Milky Way in a bid to map our galaxy’s structure and explain how it formed.

The stellar nursery NGC 6357 in the constellation of Scorpius

Located around 8000 light-years away in the constellation of Scorpius (The Scorpion), NGC 6357 — sometimes nicknamed the Lobster Nebula [1] due to its appearance in visible-light images — is a region filled with vast clouds of gas and tendrils of dark dust. These clouds are forming stars, including massive hot stars which glow a brilliant blue-white in visible light.

Wide-field view of the area of NGC 6357

This image uses infrared data from ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) at the Paranal Observatory in Chile. It is just a small part of a huge survey called VISTA Variables in the Vía Láctea (VVV) that is imaging the central parts of the Galaxy (eso1242). The new picture presents a drastically different view to that seen in visible-light images — such as the image taken with the 1.5-metre Danish telescope at La Silla — as infrared radiation can penetrate much of the covering of dust that shrouds the object [2].

Comparison of VISTA image of NGC 6357 with a visible light image

One of the bright young stars in NGC 6357, known as Pismis 24-1, was thought to be the most massive star known — until it was found to actually be made up of at least three huge bright stars, each with a mass of under 100 times that of our Sun. Even so, these stars are still heavyweights — some of the most massive in our Milky Way. Pismis 24-1 is the brightest object in the Pismis 24 star cluster, a bunch of stars that are all thought to have formed at the same time within NGC 6357.

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Comparison of VISTA image of NGC 6357 with a visible light image

VISTA is the largest and most powerful survey telescope ever built, and is dedicated to surveying the sky in infrared light. The VVV survey is scanning the central bulge and some of the plane of our galaxy to create a huge dataset that will help astronomers to discover more about the origin, early life, and structure of the Milky Way.

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Zooming in on a VISTA infrared image of NGC 6357

Parts of NGC 6357 have also been observed by the NASA/ESA Hubble Space Telescope (heic0619a) and ESO’s Very Large Telescope (eso1226a). Both telescopes have produced visible-light images of various parts of this region — comparing these images with this new infrared image above shows some striking differences. In the infrared the large plumes of red-hued material are much reduced, with tendrils of pale, purple gas stretching out from the nebula in different areas.

Notes:

[1] The informal name of Lobster Nebula is also sometimes given to the spectacular star-forming region Messier 17 (eso0925), although that object is more often called the Omega Nebula.

[2] Infrared observations can reveal features that cannot be seen in visible-light pictures, for example because an object is too cold, obscured by thick dust, or is very distant, meaning that its light has been stretched towards the red end of the spectrum by the expansion of the Universe.

More information:

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:

Photos of VISTA: http://www.eso.org/public/images/archive/search/?adv=&subject_name=Visible%20and%20Infrared%20Survey%20Telescope%20for%20Astronomy

Pictures of Paranal Observatory: http://www.eso.org/public/images/archive/category/paranal/

Other images taken with VISTA: http://www.eso.org/public/images/archive/search/?adv=&facility=30

Images Text, Credits: ESO / VVV Survey / D. Minniti. Acknowledgement: Ignacio Toledo / IAU and Sky & Telescope/Davide De Martin (ESA / Hubble), the ESA / ESO / NASA Photoshop FITS Liberator & Digitized Sky Survey 2 / Videos: ESO / VVV Survey / D. Minniti / Digitized Sky Survey 2 / Nick Risinger (skysurvey.org). Acknowledgement: Ignacio Toledo. Music: movetwo.

Best regards, Orbiter.ch

A cool discovery about the Sun’s next-door twin‏












ESA - Herschel Mission patch.

20 February 2013

 Cool layer in a Sun-like star

ESA’s Herschel space observatory has detected a cool layer in the atmosphere of Alpha Centauri A, the first time this has been seen in a star beyond our own Sun. The finding is not only important for understanding the Sun’s activity, but could also help in the quest to discover proto-planetary systems around other stars.

The Sun’s nearest neighbours are the three stars of the Alpha Centauri system. The faint red dwarf, Proxima Centauri, is nearest at just 4.24 light-years, with the tight double star, Alpha Centauri AB, slightly further away at 4.37 light-years.

Alpha Centauri B has recently been in the news after the discovery of an Earth-mass planet in orbit around it. But Alpha Centauri A is also very important to astronomers: almost a twin to the Sun in mass, temperature, chemical composition and age, it provides an ideal natural laboratory to compare other characteristics of the two stars.

One of the great curiosities in solar science is that the Sun’s wispy outer atmosphere – the corona – is heated to millions of degrees while the visible surface of the Sun is ‘only’ about 6000ºC. Even stranger, there is a temperature minimum of about 4000ºC between the two layers, just a few hundred kilometres above the visible surface in the part of Sun’s atmosphere called the chromosphere.

Both layers can be seen during a total solar eclipse, when the Moon briefly blocks the bright face of the Sun: the chromosphere is a pink-red ring around the Sun, while the ghostly white plasma streamers of the corona extend out millions of kilometres.

ESA’s Herschel space observatory

The heating of the Sun’s atmosphere has been a conundrum for many years, but is likely to be related to the twisting and snapping of magnetic field lines sending energy rippling through the atmosphere and out into space – possibly in the direction of Earth – as solar storms. Why there is a temperature minimum has also long been of interest to solar scientists.

Now, by observing Alpha Centauri A in far-infrared light with Herschel and comparing the results with computer models of stellar atmospheres, scientists have made the first discovery of an equivalent cool layer in the atmosphere of another star.

“The study of these structures has been limited to the Sun until now, but we clearly see the signature of a similar temperature inversion layer at Alpha Centauri A,” says René Liseau of the Onsala Space Observatory, Sweden, and lead author of the paper presenting the results.

“Detailed observations of this kind for a variety of stars might help us decipher the origin of such layers and the overall atmospheric heating puzzle.”

More about:

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

Online Showcase of Herschel Images OSHI: http://oshi.esa.int/

Related links:

Herschel postcard gallery: http://archives.esac.esa.int/hsa/aio/doc/postcardGallery.html

The Milky Way Project: http://www.milkywayproject.org/

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, Credit: ESA.

Cheers, Orbiter.ch

mardi 19 février 2013

Engineers Design Plant Habitat For Space Station












ISS - International Space Station patch.

February 19, 2013

 International Space Station

Some of the research on the International Space Station focuses on meeting the needs of long-term spaceflight to destinations such as asteroids or Mars. A group of engineers at NASA's Kennedy Space Center in Florida is developing a plant habitat with a large growth chamber to learn the effects of long-duration microgravity exposure to plants in space.

Through most of Kennedy's history, the space center has focused on receiving, processing and launching vehicles developed at other centers. Design projects such as the plant habitat give people at the Florida spaceport an opportunity to further use their extensive knowledge base in preparing flight hardware.

"This is the first Kennedy-led space station payload of this magnitude," said Bryan Onate, Plant Habitat Project manager in the ISS Ground Processing and Research Directorate. "We're using in-house expertise to develop the plant habitat to go on an EXPRESS rack in the station's Destiny laboratory. It will provide a large, enclosed, environmentally-controlled chamber designed to support commercial and fundamental plant research onboard the space station."

The plant habitat is configured as a payload that will be mounted on a standard Expedite the Processing of Experiments to Space Station, or EXPRESS, rack. The multipurpose payload rack system stores and supports research and science experiments across many disciplines by providing structural interfaces, power, data, cooling, water and other needs to operate science payloads in orbit.


Image above: Some of the research on the International Space Station is already focusing on meeting the needs of long-term spaceflights beyond low-Earth orbit. During Expedition 29 in 2011, Russian cosmonaut Sergei Volkov checks the progress of new growth in the Rastenia investigation aboard the space station. (NASA).

The compact facility is about 21 inches high, 36 inches wide and 24 inches deep and would use about 735 watts of power.

"NASA is conducting plant research aboard the space station because during future long-duration missions, life in space may depend on it," Onate said.

As NASA plans missions beyond low-Earth orbit, relying on plant growth aboard a spacecraft will play an important role.

"The ability of plants to provide high quality science within a tightly closed system, a source of food and recycle carbon dioxide into breathable oxygen may prove crucial for astronauts and add to the body of knowledge as they live in space for months at a time," he said.

Onate explained that most of the experiments conducted on the space station are developed by principal investigators from universities or other research institutions.

"The plant habitat is an effort to attract a broader audience of principle investigators that need a large growth area for a long duration," he said. "In order to expedite this capability on the space station, we have contracted with Orbital Technologies Corp. to help us design, fabricate and certify the plant habitat for flight."

Based in Madison, Wis., Orbital Technologies Corp., better known as ORBITEC, is a leading subsystems integrator and high-technology development company.

The plant habitat's design includes the ability to control temperature, humidity, carbon dioxide levels and lighting.

"Lighting is an important part of plant growth," Onate said. "We're using LEDs in this payload. Our experience shows that the LEDs work well in plant growth experiments in our labs here at Kennedy."


Image above: NASA is using in-house expertise to develop this plant habitat to go on an EXPRESS rack, like the one pictured above, in the International Space Station's Destiny laboratory. It will provide a large, enclosed, environmentally controlled chamber designed to support commercial and fundamental plant research aboard the space station. (NASA).

Within the plant habitat there is a tray called a science carrier that will hold various types of plants. The science carrier is a removable and reconfigurable tray that will provide the primary structural support and final water delivery to the root-zone for in-orbit plant growth experimentation.

The science carrier consists of a structural element, a water delivery mechanism, and a standard interface plate that will provide instrumentation support as part of the basic plant habitat capabilities. The carrier also will provide additional instrumentation interfaces for other experiment-specific measurement data required to allow investigators to extend the habitat's basic capabilities.

"Our design will allow principal investigators to modify the carriers depending on the type of plants they want to grow and the kind of experiments they have in mind," Onate said.

Plant habitat investigations can use the microgravity of space and can run 30, 60 or 90 days depending on the nature of the research.

"These trays will have a system of tubes allowing astronauts conducting the experiment to inject water and other plant nutrients into the media supporting plant growth," Onate said.

One of the next steps for the plant habitat is a preliminary design review in February. During the review, engineers will report on how the project is progressing to ensure the design meets system requirements within acceptable risk and falls within schedule and budget constraints.

"One of the design challenges we're dealing with now is the physical size and power requirements for the plant habitat," Onate said. "Weight, volume and maximizing valuable space station resources are always an important consideration for any payload designed for spaceflight."

"Launch of the Kennedy-designed plant habitat will likely go up on a SpaceX Dragon spacecraft," Onate said. "It is targeted for launch in December 2015."

International Space Station: http://www.nasa.gov/mission_pages/station/main/index.html

Expedite the Processing of Experiments to Space Station, or EXPRESS: http://www.nasa.gov/mission_pages/station/research/experiments/EXPRESS_Racks.html

Images (mentioned), Text, Credit: NASA's Kennedy Space Center/ Bob Granath.

Greetings, Orbiter.ch

Russia asteroid impact: ESA update and assessment‏











Asteroid Watch.

19 February 2013

The first firm details of the 15 February asteroid impact in Russia, the largest in more than a century, are becoming clear. ESA is carefully assessing the information as crucial input for developing the Agency’s asteroid-hunting effort.

At 03:20 GMT on 15 February, a natural object entered the atmosphere and disintegrated in the skies over Chelyabinsk, Russia.

Asteroid trace over Chelyabinsk, Russia, on 15 February 2013

Extensive video records indicate a northeast to southwest path at a shallow angle of 20° above the horizontal. The entry speed is estimated at around 18 km/s – more than 64 000 km/h.

According to calculations by Peter Brown at the University of Western Ontario, Canada, drawing on extremely low-frequency sound waves detected by a global network, the object is estimated to have been about 17 m across with a mass of 7000–10 000 tonnes when it hit atmosphere.

It exploded with a force of nearly 500 kilotons of TNT – some 30 times the energy released by the Hiroshima atomic bomb – around 15–20 km above the ground.

With our current understanding of near-Earth objects, events of this magnitude are expected once every several of tens to 100 years.

Questions and answers with ESA's near-Earth object team

Nicolas Bobrinsky, Head of ESA’s Space Situational Awareness (SSA) programme, and Detlef Koschny, responsible for the programme’s Near-Earth Object activity, responded to questions about the event.

Orbit around Sun

- Was this event related to the predicted flyby of asteroid 2012 DA14, which passed Earth at 19:27 GMT that same day at just 28 000 km?

DVK: The trajectory, the location of entry into the atmosphere and the large time separation between the two events indicate that the Russian object was unrelated to 2012 DA14.

- What caused the damage on the ground? Did pieces hit people or buildings?

DVK: Many media reported that an airburst caused window breakage and some structural damage in downtown Chelaybinsk. Normally, some damage begins to occur at around five times normal air pressure at sea level. Widespread window damage is expected around 10–20 times this value.

As the explosion and fireball progressed along a shallow trajectory, the cylindrical blast wave would have propagated directly to the ground and would have been intense.

The terminal part of the explosion probably likely occurred almost directly over Chelyabinsk. This was perhaps the single greatest contributor to the blast damage.

video
Scientists have found fragments of the meteorite Chelyabinsk (in Russian)

We are waiting for confirmation from the Russian authorities that pieces of the object – bits of meteorite – have been found in the region. We’re unaware of any media reports of anyone or any structure being hit by any debris from the object itself.

Related links:

Space Situational Awareness: http://www.esa.int/Our_Activities/Operations/Space_Situational_Awareness2

Russian asteroid strike: http://orbiterchspacenews.blogspot.ch/2013/02/russian-asteroid-strike.html

Stranger in the night: space rock to make close Earth flyby: http://www.esa.int/Our_Activities/Operations/Stranger_in_the_night_space_rock_to_make_close_Earth_flyby

Asteroid 2012 DA14 - Near-Earth Asteroid Makes View Appearance: http://orbiterchspacenews.blogspot.ch/2013/02/asteroid-2012-da14-near-earth-asteroid.html

Spotting an ancient asteroid: http://www.esa.int/Our_Activities/Operations/Spotting_an_ancient_asteroid

SSA NEO Data Centre: http://neo.ssa.esa.int/

More information:

Centre for Planetary Science and Exploration: http://planetsci.uwo.ca/

Infrasound monitoring: http://www.ctbto.org/verification-regime/monitoring-technologies-how-they-work/infrasound-monitoring/

UNCOPUOS: http://www.oosa.unvienna.org/oosa/COPUOS/copuos.html

UNCOPUOS - 2013 session - presentations: http://www.unoosa.org/oosa/en/COPUOS/stsc/2013/presentations.html

Images, Video, Text, Credits: ESA / Alex Alishevskikh CC BY-SA 2.0 via http://www.flickr.com/photos/alexeya/ NASA / ROSCOSMOS TV / Russia 24.

Greetings, Orbiter.ch

The Patrouille Suisse will continue to exist












Swiss Air Force - Patrouille Suisse patch.

February 19, 2013

The outcry caused by the announcement of the "death" of the Swiss aerobatic team, the defense minister backtracked. But the aircraft will lose the Swiss colors.

The Swiss army will continue to have an aerobatic flight training, but not in red and white, said the defense minister in an interview. It would cost 50 million francs more each year to keep the F-5 Tiger aircraft currently used by the Patrouille Suisse, he said.

Actual colors of the Patrouille Suisse with F-5E Tiger II

In its previous announcement, he called the Patrouille Suisse of "Folklore" and claimed that his grounding was motivated by economic reasons. In reaction to these remarks, many politicians and citizens have exclaimed: "It is as bad to buy a plane that Gripen is Folklore".

Reactions to a possible suppression of the Patrouille Suisse surprised, says defense minister in an interview published Tuesday by the newspaper "Nordwestschweiz." "It has been clear for months with the shelved F-5 Tiger Patrouille Suisse no longer exist in its current form."

If Tiger F-5 were retained, the Air Force possesses three fleets after the planned purchase of Swedish Gripen: F/A-18, Gripen and the Tiger. According to the minister of defense, he "would cost 30 million francs more than today."

"We can not afford it." But the army will continue to have training in aerobatics. "We have planes and pilots trained accordingly. But we can not paint the Swiss cross on the devices. "

Problem of quantity
There is a problem of quantity, says the head of the Department of Defense (DDPS). The Air Force currently has 54 Tiger yet. Eleven of them made up the Patrouille Suisse. In the future, Switzerland will have more than 55 Gripen and F/A-18. "We can not do paint ten of them."

The defense minister said last week that the aerobatic formation of the Swiss army colors should disappear aviation landscape. He made the announcement at a meeting of the Committee of the security policy of the National Council.

F/A-18 Hornet in Patrouille Suisse, the question remains open

The question whether the Patrouille Suisse fly with Gripen or F/A-18 remains open, said the defense minister. The old Tiger could still fly two or three years. "But then it would definitely be finished."

Editor Note: there is actually a bigger problem of quantity, as I wrote in a previous article (see links at the end of the article), the performance of the Gripen are so inadequate that 3 Gripen to make the work of a Rafale, so to ensure all future missions with only 22 aircraft, the choice of the Rafale should win, it's a safe bet that the file will end in popular vote and in this case, the Gripen will be refused.

The Rafale, the best choice for Swiss Air Force!

Discover or read previous articles on this issue:

Choice of a new fighter aircraft of the Swiss Air Force: Description and comparison:
http://orbiterchspacenews.blogspot.ch/2013/01/choice-of-new-fighter-aircraft-of-swiss.html

Swiss Air Force - The Gripen saga continues ...:
http://orbiterchspacenews.blogspot.ch/2013/02/swiss-air-force-gripen-saga-continues.html

Patrouille Suisse: a boss flies to the rescue:
http://orbiterchspacenews.blogspot.ch/2013/02/patrouille-suisse-boss-flies-to-rescue.html

Images, Text, Credits: ATS / Swiss Air Force / Orbiter.ch Aerospace.

Best regards, Orbiter.ch

lundi 18 février 2013

Asteroid Steins' Hidden Gems












ESA - Rosetta Mission patch.

18 February 2013

 Steins revisited

ESA’s Rosetta spacecraft snapped images of asteroid Steins as it flew by the diamond-shaped asteroid on 5 September 2008, revealing a tiny world with a big history of collisions.

The images were taken by Rosetta’s Wide Angle Camera as the spacecraft flew within 800 km of the 5 km-wide asteroid, and later processed by amateur astronomer Ted Stryk to produce the image presented here.

By emphasising the shadows, the processing reveals high-contrast features, such as bright crater rims against their dark, shadowed interiors. However, this technique can also create some artifacts, such as the illusion of boulders protruding from the surface, that are not present in the raw data.

One striking feature is the gaping hole at the south pole (top in this image) of Steins – its largest impact crater at about 2 km wide and nearly 300 m deep. This crater is named ‘Diamond’ following the gem nomenclature chosen after the asteroid’s overall shape earned it the nickname ‘diamond in the sky’.

The circular crater in the centre of the asteroid as seen in this viewing angle is called Topaz and is about 650 m wide and 80 m deep.

A chain of several craters can be seen stretching from the asteroid’s north pole (bottom in this image) right up to Diamond crater.

So far, around 40 craters have been found, but the imposing Diamond crater likely influenced the appearance of the entire asteroid because the debris thrown out from this dramatic collision would have scattered over the surface, imprinting over other, older craters.

Rosetta spacecraft

Rosetta has since passed by asteroid Lutetia in July 2010 and is now in deep-space hibernation. It will wake up on 20 January 2014 and rendezvous with comet 67P/Churyumov–Gerasimenko in May 2014. A few months later, its Philae probe will separate to make the first controlled landing on a comet.

Comets are considered to be the primitive building blocks of the Solar System, and Rosetta will help scientists to learn more about their role in the evolution of our local cosmic neighbourhood.

More about:

Rosetta: http://www.esa.int/Our_Activities/Space_Science/Rosetta

Related link:

This image on Ted Stryk’s blog: http://planetimages.blogspot.nl/2012/04/steins-closest-approach.html

New science paper on Steins’ craters: http://www.sciencedirect.com/science/article/pii/S0019103512003272

Rosetta data archive: http://www.sciops.esa.int/index.php?project=PSA&page=rosetta

Rosetta in depth: http://sci.esa.int/rosetta

Images, Text, Credits: ESA / J. Huart / MPS for OSIRIS Team / MPS / UPD / LAM / IAA / RSSD / INTA / UPM / DASP / IDA; processing by T. Stryk.

Greetings, Orbiter.ch