vendredi 19 février 2016
NASA - Hubble Space Telescope patch.
Feb. 19, 2016
Surrounded by an envelope of dust, the subject of this NASA/ESA Hubble Space Telescope image is a young forming star known as HBC 1. The star is in an immature and adolescent phase of life, while most of a sun-like star’s life is spent in a stable stage comparable to human adulthood.
In this view, HBC 1 illuminates a wispy reflection nebula known as IRAS 00044+6521. Formed from clouds of interstellar dust, reflection nebulae do not emit any visible light of their own. Instead, like fog encompassing a lamppost, they shine via the light reflected off the dust from the stars embedded within. Though nearby stars cannot ionize the nebula’s dust, as they can for gas within brighter emission nebulae, scattered starlight can make the dust visible in a reflection nebula.
For images and more information about Hubble, visit:
Text Credits: European Space Agency/NASA/Ashley Morrow/Image Credits: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 14:27
NASA - Mars Reconnaissance Orbiter (MRO) patch.
Feb. 19, 2016
This image, acquired on Nov. 24, 2015 by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter, shows the western side of an elongated pit depression in the eastern Noctis Labyrinthus region of Mars. Along the pit's upper wall is a light-toned layered deposit. Noctis Labyrinthus is a huge region of tectonically controlled valleys located at the western end of the Valles Marineris canyon system.
Spectra extracted from the light-toned deposit by the spacecraft's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument are consistent with the mineral jarosite, which is a potassium and iron hydrous sulfate. On Earth, jarosite can form in ore deposits or from alteration near volcanic vents, and indicates an oxidizing and acidic environment. The Opportunity rover discovered jarosite at the Meridiani Planum landing site, and jarosite has been found at several other locations on Mars, indicating that it is a common mineral on the Red Planet.
The jarosite-bearing deposit observed here could indicate acidic aqueous conditions within a volcanic system in Noctis Labyrinthus. Above the light-toned jarosite deposit is a mantle of finely layered darker-toned material. CRISM spectra do not indicate this upper darker-toned mantle is hydrated. The deposit appears to drape over the pre-existing topography, suggesting it represents an airfall deposit from either atmospheric dust or volcanic ash.
Mars Reconnaissance Orbiter (MRO) spacecraft
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.
For more information about Mars Reconnaissance Orbiter (MRO):
Images, Text, Credits: NASA/JPL-Caltech/Univ. of Arizona/Caption: Cathy Weitz/Sarah Loff.
Publié par Orbiter.ch à 14:20
jeudi 18 février 2016
CERN - European Organization for Nuclear Research logo.
Feb. 18, 2016
What if there was a technology that could accelerate particles with hundreds of times more power than current methods? The AWAKE experiment, under construction at CERN, is preparing to test this question with proton-driven plasma wakefield acceleration. On Thursday, 11 February, a key component was lowered into the tunnel and put into place: the 10-metre-long plasma cell, which was developed by the Max Planck Institute for Physics, in Munich.
Modern accelerators rely on electric fields and charged particles are accelerated using radiofrequency (RF) cavities. The electric field alternates inside the cavities, and “kicks” the incoming particles to accelerate them. With this technology, building more powerful accelerators means larger accelerators.
Image above: AWAKE's 10-metre-long plasma cell developed by MPP has been moved into place in the experiment tunnel. (Image: Maximilien Brice/CERN).
Plasma wakefield acceleration could offer an alternative technology. A proton beam, known as the “drive beam”, is injected into an ionized gas – or plasma – and attracts free electrons while passing through it, creating waves of electric charges in the wake of the proton beam. A second beam of electrons, the “witness” beam, injected in the right phase behind the proton beam, feels the wakefield and gets accelerated, just as a surfer rides a wave.
Plasma wakefield acceleration has been already demonstrated in laboratories around the world using an electron beam as drive beam. What makes AWAKE different, and a proof-of-principle experiment, is that it aims to test plasma wakefield generation using, for the first time, protons. This can only be done at CERN as it requires high-energy proton beams. That is why AWAKE will be installed in the facility formerly used by the CNGS experiment, using the proton beam coming out from the Super Proton Synchrotron (SPS). The reason to try protons is that because they have higher energy than an electron beam used for plasma wakefield acceleration, they can penetrate more into the plasma, causing a longer “wave” and therefore a more powerful acceleration. Physicists think they could produce accelerations hundreds of times higher than those achieved with RF cavities.
AWAKE - Transport of the plasma cell in the tunnel
Video above: Interview with Edda Gschwendtner, AWAKE project leader, on the day the AWAKE's plasma cell is transported from the surface hall where it was tested, to the AWAKE tunnel in CERN's SPS decay tunnel. (Video: Jacques Herve Fichet/Paola Catapano/CERN).
AWAKE will complete its first phase of installation this year, with the installation of the laser, the vacuum equipment and the diagnostic system for both laser and proton beams. It plans to start the first phase of the experimentation at the end of the year, where the physics of the proton-driven plasma wakefield will be tested. Next year, the electron source and the electron beam line will be installed to then test the injection of electron beam and its effective acceleration through the plasma.
“There are still many challenges to overcome”, says Edda Gschwendtner, CERN AWAKE project leader. “But if this technology really materialises, the future is very bright. We could have much shorter linear colliders, we might have table-top accelerators, also for medical applications.”
For more information, watch this TEDxCERN talk given by Edda Gschwendtner: http://tedxcern.web.cern.ch/video/2015/surfing-wakefields-create-smaller-accelerators
Awakening the potential of plasma acceleration:
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.
The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.
Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.
Radiofrequency (RF) cavities: http://home.cern/about/engineering/radiofrequency-cavities
Super Proton Synchrotron (SPS): http://home.cern/about/accelerators/super-proton-synchrotron
For more information about the European Organization for Nuclear Research (CERN), visit: http://home.web.cern.ch/
Image (mentioned), Video (mentioned), Text, Credits: CERN/Stefania Pandolfi/Harriet Kim Jarlett.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 15:46
NASA Hubble Space Telescope patch.
Feb. 18, 2016
Astronomers using NASA's Hubble Space Telescope have measured the rotation rate of an extreme exoplanet by observing the varied brightness in its atmosphere. This is the first measurement of the rotation of a massive exoplanet using direct imaging.
"The result is very exciting," said Daniel Apai of the University of Arizona in Tucson, leader of the Hubble investigation. "It gives us a unique technique to explore the atmospheres of exoplanets and to measure their rotation rates."
The planet, called 2M1207b, is about four times more massive than Jupiter and is dubbed a "super-Jupiter." It is a companion to a failed star known as a brown dwarf, orbiting the object at a distance of 5 billion miles. By contrast, Jupiter is approximately 500 million miles from the sun. The brown dwarf is known as 2M1207. The system resides 170 light-years away from Earth.
Image above: This is an illustration of a planet that is four times the mass of Jupiter and orbits 5 billion miles from a brown dwarf companion object (the bright red star seen in the background). The planet is only 170 light-years away. Our sun is a faint star in the background. Image Credits: NASA, ESA, and G. Bacon/STScI.
Hubble's image stability, high resolution, and high-contrast imaging capabilities allowed astronomers to precisely measure the planet's brightness changes as it spins. The researchers attribute the brightness variation to complex clouds patterns in the planet's atmosphere. The new Hubble measurements not only verify the presence of these clouds, but also show that the cloud layers are patchy and colorless.
Astronomers first observed the massive exoplanet 10 years ago with Hubble. The observations revealed that the exoplanet's atmosphere is hot enough to have "rain" clouds made of silicates: vaporized rock that cools down to form tiny particles with sizes similar to those in cigarette smoke. Deeper into the atmosphere, iron droplets are forming and falling like rain, eventually evaporating as they enter the lower levels of the atmosphere.
"So at higher altitudes it rains glass, and at lower altitudes it rains iron," said Yifan Zhou of the University of Arizona, lead author on the research paper. "The atmospheric temperatures are between about 2,200 to 2,600 degrees Fahrenheit."
The super-Jupiter is so hot that it appears brightest in infrared light. Astronomers used Hubble's Wide Field Camera 3 to analyze the exoplanet in infrared light to explore the object's cloud cover and measure its rotation rate. The planet is hot because it is only about 10 million years old and is still contracting and cooling. For comparison, Jupiter in our solar system is about 4.5 billion years old.
The planet, however, will not maintain these sizzling temperatures. Over the next few billion years, the object will cool and fade dramatically. As its temperature decreases, the iron and silicate clouds will also form lower and lower in the atmosphere and will eventually disappear from view.
Zhou and his team have also determined that the super-Jupiter completes one rotation approximately every 10 hours, spinning at about the same fast rate as Jupiter.
Hubble orbiting Earth
This super-Jupiter is only about five to seven times less massive than its brown-dwarf host. By contrast, our sun is about 1,000 times more massive than Jupiter. "So this is a very good clue that the 2M1207 system we studied formed differently than our own solar system," Zhou explained. The planets orbiting our sun formed inside a circumstellar disk through accretion. But the super-Jupiter and its companion may have formed throughout the gravitational collapse of a pair of separate disks.
"Our study demonstrates that Hubble and its successor, NASA's James Webb Space Telescope, will be able to derive cloud maps for exoplanets, based on the light we receive from them," Apai said. Indeed, this super-Jupiter is an ideal target for the Webb telescope, an infrared space observatory scheduled to launch in 2018. Webb will help astronomers better determine the exoplanet's atmospheric composition and derive detailed maps from brightness changes with the new technique demonstrated with the Hubble observations.
Results from this study will appear in the Feb. 11, 2016, edition of The Astrophysical Journal.
For images and more information about Hubble, visit:
Image (mentioned), Text, Credits: NASA/Ashley Morrow/ESA/Space Telescope Science Institute/Donna Weaver/Ray Villard.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 14:24
NASA - New Horizons Mission logo.
Feb. 18, 2016
Pluto’s largest moon may have gotten too big for its own skin.
Images from NASA’s New Horizons mission suggest that Pluto’s moon Charon once had a subsurface ocean that has long since frozen and expanded, pushing outward and causing the moon’s surface to stretch and fracture on a massive scale.
The side of Pluto’s largest moon viewed by NASA’s passing New Horizons spacecraft in July 2015 is characterized by a system of “pull apart” tectonic faults, which are expressed as ridges, scarps and valleys—the latter sometimes reaching more than 4 miles (6.5 kilometers) deep. Charon’s tectonic landscape shows that, somehow, the moon expanded in its past, and – like Bruce Banner tearing his shirt as he becomes the Incredible Hulk – Charon’s surface fractured as it stretched.
The outer layer of Charon is primarily water ice. This layer was kept warm when Charon was young by heat provided by the decay of radioactive elements, as well as Charon’s own internal heat of formation. Scientists say Charon could have been warm enough to cause the water ice to melt deep down, creating a subsurface ocean. But as Charon cooled over time, this ocean would have frozen and expanded (as happens when water freezes), lifting the outermost layers of the moon and producing the massive chasms we see today.
Image above: A close-up of the canyons on Charon, Pluto's big moon, taken by New Horizons during its close approach to the Pluto system last July. Multiple views taken by New Horizons as it passed by Charon allow stereo measurements of topography, shown in the color-coded version of the image. The scale bar indicates relative elevation. Image Credits: NASA/JHUAPL/SwRI.
The top portion of this image shows part of the feature informally named Serenity Chasma, part of a vast equatorial belt of chasms on Charon. In fact, this system of chasms is one of the longest seen anywhere in the solar system, running at least 1,100 miles (about 1,800 kilometers) long and reaching 4.5 miles (7.5 kilometers) deep. By comparison, the Grand Canyon is 277 miles (446 kilometers) long and just over a mile (1.6 kilometers) deep.
The lower portion of the image shows color-coded topography of the same scene. Measurements of the shape of this feature tell scientists that Charon’s water ice layer may have been at least partially liquid in its early history, and has since refrozen.
This image was obtained by the Long-Range Reconnaissance Imager (LORRI) on New Horizons. North is up; illumination is from the top-left of the image. The image resolution is about 1,290 feet (394 meters) per pixel. The image measures 240 miles (386 kilometers) long and 110 miles (175 kilometers) wide. It was obtained at a range of approximately 48,900 miles (78,700 kilometers) from Charon, about an hour and 40 minutes before New Horizons’ closest approach to Charon on July 14, 2015.
For more information about New Horizons, visit:
Image (mentioned), Text, Credits: NASA/Tricia Talbert.
Publié par Orbiter.ch à 14:12
NASA - Wide Field Infrared Survey Telescope (WFIRST) logo.
Feb. 18, 2016
Image above: NASA's Wide Field Infrared Survey Telescope (WFIRST), illustrated here, will carry a Wide Field Instrument to capture Hubble-quality images covering large swaths of sky, enabling cosmic evolution studies. Its Coronagraph Instrument will directly image exoplanets and study their atmospheres. Image Credits: NASA/GSFC/Conceptual Image Lab.
After years of preparatory studies, NASA is formally starting an astrophysics mission designed to help unlock the secrets of the universe -- the Wide Field Infrared Survey Telescope (WFIRST).
With a view 100 times bigger than that of NASA’s Hubble Space Telescope, WFIRST will aid researchers in their efforts to unravel the secrets of dark energy and dark matter, and explore the evolution of the cosmos. It also will discover new worlds outside our solar system and advance the search for worlds that could be suitable for life.
NASA's Agency Program Management Council, which evaluates the agency's programs and projects on content, risk management, and performance, made the decision to move forward with the mission on Wednesday.
“WFIRST has the potential to open our eyes to the wonders of the universe, much the same way Hubble has,” said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate at Headquarters in Washington. "This mission uniquely combines the ability to discover and characterize planets beyond our own solar system with the sensitivity and optics to look wide and deep into the universe in a quest to unravel the mysteries of dark energy and dark matter.”
WFIRST is the agency's next major astrophysics observatory, following the launch of the James Webb Space Telescope in 2018. The observatory will survey large regions of the sky in near-infrared light to answer fundamental questions about the structure and evolution of the universe, and expand our knowledge of planets beyond our solar system – known as exoplanets.
It will carry a Wide Field Instrument for surveys, and a Coronagraph Instrument designed to block the glare of individual stars and reveal the faint light of planets orbiting around them. By blocking the light of the host star, the Coronagraph Instrument will enable detailed measurements of the chemical makeup of planetary atmospheres. Comparing these data across many worlds will allow scientists to better understand the origin and physics of these atmospheres, and search for chemical signs of environments suitable for life.
"WFIRST is designed to address science areas identified as top priorities by the astronomical community," said Paul Hertz, director of NASA's Astrophysics Division in Washington. “The Wide-Field Instrument will give the telescope the ability to capture a single image with the depth and quality of Hubble, but covering 100 times the area. The coronagraph will provide revolutionary science, capturing the faint, but direct images of distant gaseous worlds and super-Earths."
WFIRST The Best of Both Worlds
Video above: The WFIRST will image large regions of the sky in near-infrared light to answer fundamental questions about the structure and evolution of the universe and greatly expand our knowledge of planetary systems around other stars. Image Credit: NASA.
The telescope’s sensitivity and wide view will enable a large-scale search for exoplanets by monitoring the brightness of millions of stars in the crowded central region of our galaxy. The survey will net thousands of new exoplanets similar in size and distance from their star as those in our own solar system, complementing the work started by NASA's Kepler mission and the upcoming work of the Transiting Exoplanet Survey Satellite.
Employing multiple techniques, astronomers also will use WFIRST to track how dark energy and dark matter have affected the evolution of our universe. Dark energy is a mysterious, negative pressure that has been speeding up the expansion of the universe. Dark matter is invisible material that makes up most of the matter in our universe.
By measuring the distances of thousands of supernovae, astronomers can map in detail how cosmic expansion has increased with time. WFIRST also can precisely measure the shapes, positions and distances of millions of galaxies to track the distribution and growth of cosmic structures, including galaxy clusters and the dark matter accompanying them.
"In addition to its exciting capabilities for dark energy and exoplanets, WFIRST will provide a treasure trove of exquisite data for all astronomers," said Neil Gehrels, WFIRST project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "This mission will survey the universe to find the most interesting objects out there."
WFIRST is slated to launch in the mid-2020s. The observatory will begin operations after travelling to a gravitational balance point known as Earth-Sun L2, which is located about one million miles from Earth in a direction directly opposite the Sun.
WFIRST is managed at Goddard, with participation by the Jet Propulsion Laboratory (JPL) in Pasadena, California, the Space Telescope Science Institute in Baltimore, the Infrared Processing and Analysis Center, also in Pasadena, and a science team comprised of members from U.S. research institutions across the country.
For more information about NASA's WFIRST mission, visit: http://www.nasa.gov/wfirst
Image (mentioned), Video (mentioned), Text, Credits: NASA/Felicia Chou/GSFC/Lynn Chandler.
Publié par Orbiter.ch à 12:07
ESA - Mars Express Mission patch.
18 February 2016
Water has left its mark in a variety of ways in this martian scene captured by ESA’s Mars Express.
The region lies on the western rim of an ancient large impact basin, as seen in the context map. The image shows the western part of the Arda Valles, a dendritic drainage system 260 km north of Holden Crater and close to Ladon Valles.
Arda Valles context
Vast volumes of water once flowed from the southern highlands, carving Ladon Valles and ponding in the large Ladon Basin seen in this image.
The plan views show the striking dendritic drainage pattern of the valleys (left). Many contributing streams merge into tributaries of the main channels before flowing down into the smooth-floored impact basin towards the right.
Arda Valles topography
In the upper centre of the main image – also clearly identified in the topography and anaglyph images – a large mound is seen with an 8.5 km-wide impact crater at its foot. The mound is possibly the remnant of an older impact basin but may also have been influenced by sediments transported by the surrounding streams, building up a fan deposit.
In the centre right of the image, a large 25 km-wide impact crater has also been filled by thick muddy sediments that later collapsed into the chaotic terrain seen in the crater floor. The jumbled nodules in the crater rim probably indicate the former level of the infilling sediments.
Arda Valles perspective
To the top right of the scene, the surface has also broken up into a number of giant polygons, likely linked to the loss of underground ice and the slow evaporation of water that was once ubiquitous in this area.
The more concentric fracture-like features seen within the smooth floor of the large basin are likely also related to stresses in the surface resulting from the compaction of the vast amount of sediments that infill the basin.
3D view in Arda Valles
Some of the fractures seem to join the central crater to the smoother basin floor, particularly evident in the perspective view. They could be a later manifestation of stresses due to subsidence or compaction of surface materials.
Finally, in the lower centre of the image, just above the crater at the bottom of the scene and towards the end of the dendritic channels, light-toned and layered deposits have been identified. These are clay minerals, known to be formed in the presence of water.
Looking at Mars: http://www.esa.int/Our_Activities/Space_Science/Mars_Express
Mars Express overview: http://www.esa.int/Our_Activities/Space_Science/Mars_Express_overview
Mars Express 10 year brochure: http://esamultimedia.esa.int/multimedia/publications/BR-312/
Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/NASA MGS MOLA Science Team.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 06:51
mercredi 17 février 2016
NASA - Solar Dynamics Observatory (SDO) patch.
Feb. 17, 2016
Image above and Video bellow: An elongated solar prominence rose up above the sun’s surface and slowly unraveled on Feb. 3, 2016, as seen in this video by NASA’s Solar Dynamics Observatory, or SDO. Prominences, also known as filaments when seen over the sun’s limb, are clouds of solar material suspended above the sun’s surface by the solar magnetic field – the same complex magnetism that drives solar events like flares and coronal mass ejections. The solar material in the prominence streams along the sun’s magnetic field lines before it thins out and gradually breaks away from the solar surface. These images were taken in extreme ultraviolet wavelengths of 304 angstroms, a type of light that is invisible to our eyes but is colorized here in red.
NASA's SDO Sees Unraveling Solar Prominence
The sun appears to move in the last few seconds of the video because SDO was performing a guide telescope calibration.
For more information about Solar Dynamics Observatory (SDO), visit:
Image, Video, Text, Credits: NASA/SDO/Goddard Space Flight Center/Steele Hill/Sarah Frazier/Rob Garner.
Publié par Orbiter.ch à 14:11
JAXA - Japan Aerospace Exploration Agency logo.
February 17, 2016
Launch of H-IIA rocket from Tanegashima Space Center with ASTRO-H X-ray observatory
Mitsubishi Heavy Industries, Ltd. and the Japan Aerospace Exploration Agency (JAXA) successfully launched the H-IIA Launch Vehicle No. 30 (H-IIA F30) with the X-ray Astronomy Satellite (ASTRO-H) onboard at 5:45 p.m. on February 17, 2016 (Japan Standard Time, JST) from the Tanegashima Space Center. The launch vehicle flew as planned, and at approximately 14 minutes and 15 seconds after liftoff, the separation of ASTRO-H was confirmed.
The success marked the 30th milestone launch of the H-IIA, and the launch success rate reached almost 97%. In addition, the last 10 launches lifted off on time (except for some launch delays due to weather factors), and that has proved the high reliability and quality of the H-IIA Launch Vehicle. We can and will respond to demands of launch service users with confidence and high reliability.
Launch of Japanese H-IIA Rocket with ASTRO-H Onboard
We would like to express our profound appreciation for the cooperation and support of all related personnel and organizations that helped contribute to the successful launch of the H-IIA F30.
X-ray Astronomy Satellite (ASTRO-H) Solar Array Paddles Deployment and Name Decided
The Japan Aerospace Exploration Agency (JAXA) confirmed that the X-ray Astronomy Satellite (ASTRO-H) has deployed its solar array paddles (SAPs) normally through data transmitted from the satellite and received at the Uchinoura Ground Station at 5:45 p.m. on February 17, 2016. ASTRO-H was launched by the H-IIA Launch Vehicle No. 30 from the Tahegashima Space Center at 5:45 p.m. on the same day.
The satellite is currently in good health.
ASTRO-H is the eye to study the hot and energetic universe. Therefore we name ASTRO-H, “Hitomi”. The word Hitomi generally means “eye”, and specifically the pupil, or entrance window of the eye - the aperture!
X-ray Astronomy Satellite (ASTRO-H)
There is also an ancient legend that inspires the name Hitomi.
"One day, many years ago, a painter was drawing four white dragons on a street. He finished drawing the dragons, but without “Hitomi”. People who looked at the painting said “why don’t you paint Hitomi, it is not complete! The painter hesitated, but people pressured him. The painter then drew Hitomi on two of the four dragons. Immediately, these dragons came to life and flew up into the sky. The two dragons without Hitomi remained still. (Put Hitomi of Dragon in the drawing).”
The inspiration of this story is that Hitomi is regarded as the “One last, but most important part”, and so we wish ASTRO-H to be the essential mission to solve mysteries of the universe in X-rays. Hitomi refers to the aperture of the eye, the part where incoming light is absorbed. From this, Hitomi reminds us of a black hole. We will observe Hitomi in the Universe using the Hitomi satellite!
For your information, a nano-satellite “PRISM”, which was developed by Profs Nakasuka and Funase laboratory, at the University of Tokyo, and is currently in operation, shares the same name of Hitomi as its nickname. The laboratory kindly accepted our request to use the same name for ASTRO-H, and we would like to express our sincere appreciation for their cooperation.
MHI Launch Services: http://h2a.mhi.co.jp/en/index.html
H-IIA Launch Vehicle: http://global.jaxa.jp/projects/rockets/h2a/
X-ray Astronomy Satellite "ASTRO-H": http://global.jaxa.jp/projects/sat/astro_h/
Images, Video, Text, Credits: Japan Aerospace Exploration Agency (JAXA)/National Research and Development Agency/Mitsubishi Heavy Industries, Ltd.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 07:05
mardi 16 février 2016
NASA - Chandra X-ray Observatory patch.
Feb. 16, 2016
Astronomers have used NASA’s Chandra X-ray Observatory to discover a jet from a very distant supermassive black hole being illuminated by the oldest light in the Universe. This discovery shows that black holes with powerful jets may be more common than previously thought in the first few billion years after the Big Bang.
The light detected from this jet was emitted when the Universe was only 2.7 billion years old, a fifth of its present age. At this point, the intensity of the cosmic microwave background radiation, or CMB, left over from the Big Bang was much greater than it is today.
The length of the jet, found in the system known as B3 0727+409, is at least 300,000 light years. Many long jets emitted by supermassive black holes have been detected in the nearby Universe, but exactly how these jets give off X-rays has remained a matter of debate. In B3 0727+409, it appears that the CMB is being boosted to X-ray wavelengths.
Image above: Extended X-ray jet associated with quasar B3 0727+409. Image Credits: X-ray: NASA/CXC/ISAS/A. Simionescu et al, Optical: DSS.
“Because we’re seeing this jet when the Universe was less than three billion years old, the jet is about 150 times brighter in X-rays than it would be in the nearby Universe,” said Aurora Simionescu at JAXA’s Institute of Space and Astronautical Studies (ISAS) who led the study.
As the electrons in the jet fly from the black hole at close to the speed of light, they move through the sea of CMB radiation and collide with microwave photons, boosting the energy of the photons up into the X-ray band to be detected by Chandra. This implies that the electrons in the B3 0727+409 jet must keep moving at nearly the speed of light for hundreds of thousands of light years.
Electrons in black hole jets usually emit strongly at radio wavelengths, so typically these systems are found using radio observations. The discovery of the jet in B3 0727+409 is special because so far almost no radio signal has been detected from this object, while it is easily seen in the X-ray image.
“We essentially stumbled onto this remarkable jet because it happened to be in Chandra’s field of view while we were observing something else,” explains co-author Lukasz Stawarz of Jagiellonian University in Poland.
Artist's view of Chandra X-ray Observatory spacecraft. Image Credits: NASA/CXC
Scientists have so far identified very few jets distant enough that their X-ray brightness is amplified by the CMB as clearly as in the B3 0727+409 system. But, Stawarz adds, “if bright X-ray jets can exist with very faint or undetected radio counterparts, it means that there could be many more of them out there because we haven’t been systematically looking for them.”
“Supermassive black hole activity, including the launching of jets, may be different in the early Universe than what we see later on,” said co-author Teddy Cheung of the Naval Research Laboratory in Washington DC. “By finding and studying more of these distant jets, we can start to grasp how the properties of supermassive black holes might change over billions of years.”
These results were published in the January 1st, 2016 issue of The Astrophysical Journal Letters and appear online. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.
Read More from NASA's Chandra X-ray Observatory: http://chandra.harvard.edu/
For more Chandra images, multimedia and related materials, visit: http://www.nasa.gov/chandra
Images (mentioned), Text, Credits: NASA/Lee Mohon/Marshall Space Flight Center/Molly Porter/Chandra X-ray Center/Megan Watzke.
Publié par Orbiter.ch à 16:52
ESA - Hubble Space Telescope logo.
16 February 2016
Artist’s impression of 55 Cancri e
For the first time astronomers were able to analyse the atmosphere of an exoplanet in the class known as super-Earths. Using data gathered with the NASA/ESA Hubble Space Telescope and new analysis techniques, the exoplanet 55 Cancri e is revealed to have a dry atmosphere without any indications of water vapour. The results, to be published in the Astrophysical Journal, indicate that the atmosphere consists mainly of hydrogen and helium.
The international team, led by scientists from University College London (UCL) in the UK, took observations of the nearby exoplanet 55 Cancri e, a super-Earth with a mass of eight Earth-masses . It is located in the planetary system of 55 Cancri, a star about 40 light-years from Earth.
Using observations made with the Wide Field Camera 3 (WFC3) on board the NASA/ESA Hubble Space Telescope, the scientists were able to analyse the atmosphere of this exoplanet. This makes it the first detection of gases in the atmosphere of a super-Earth. The results allowed the team to examine the atmosphere of 55 Cancri e in detail and revealed the presence of hydrogen and helium, but no water vapour. These results were only made possible by exploiting a newly-developed processing technique.
Artist’s impression of 55 Cancri e (close-up)
“This is a very exciting result because it’s the first time that we have been able to find the spectral fingerprints that show the gases present in the atmosphere of a super-Earth,” explains Angelos Tsiaras, a PhD student at UCL, who developed the analysis technique along with his colleagues Ingo Waldmann and Marco Rocchetto. “The observations of 55 Cancri e’s atmosphere suggest that the planet has managed to cling on to a significant amount of hydrogen and helium from the nebula from which it originally formed.”
Super-Earths like 55 Cancri e are thought to be the most common type of planet in our galaxy. They acquired the name ‘super-Earth’ because they have a mass larger than that of the Earth but are still much smaller than the gas giants in the Solar System. The WFC3 instrument on Hubble has already been used to probe the atmospheres of two other super-Earths, but no spectral features were found in those previous studies .
55 Cancri e, however, is an unusual super-Earth as it orbits very close to its parent star. A year on the exoplanet lasts for only 18 hours and temperatures on the surface are thought to reach around 2000 degrees Celsius. Because the exoplanet is orbiting its bright parent star at such a small distance, the team was able to use new analysis techniques to extract information about the planet, during its transits in front of the host star.
Observations were made by scanning the WFC3 very quickly across the star to create a number of spectra. By combining these observations and processing them through analytic software, the researchers were able to retrieve the spectrum of 55 Cancri e embedded in the light of its parent star.
Transit of 55 Cancri e
“This result gives a first insight into the atmosphere of a super-Earth. We now have clues as to what the planet is currently like and how it might have formed and evolved, and this has important implications for 55 Cancri e and other super-Earths,” said Giovanna Tinetti, also from UCL, UK.
Intriguingly, the data also contain hints of the presence of hydrogen cyanide, a marker for carbon-rich atmospheres.
“Such an amount of hydrogen cyanide would indicate an atmosphere with a very high ratio of carbon to oxygen,” said Olivia Venot, KU Leuven, who developed an atmospheric chemical model of 55 Cancri e that supported the analysis of the observations.
“If the presence of hydrogen cyanide and other molecules is confirmed in a few years time by the next generation of infrared telescopes, it would support the theory that this planet is indeed carbon rich and a very exotic place,” concludes Jonathan Tennyson, UCL. “Although hydrogen cyanide, or prussic acid, is highly poisonous, so it is perhaps not a planet I would like to live on!”
 55 Cancri e has previously been dubbed the “diamond planet” because models based on its mass and radius have led to the idea that its interior is carbon-rich.
 Hubble observed the super-Earths GJ1214b and HD97658b in 2014, using the transit method. The observations did not show any spectral features, indicating an atmosphere covered by thick clouds made of molecular species much heavier than hydrogen.
The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
The results were summarized by Tsiaras et al. in the paper “Detection of an atmosphere around the super-Earth 55 Cancri e” which is going to be published in the Astrophysical Journal.
The team of astronomers in this study consists of A. Tsiaras (UCL, UK), M. Rocchetto (UCL, UK), I. P. Waldmann (UCL, UK), O. Venot (Katholieke Universiteit Leuven, Belgium), R. Varley (UCL, UK), G. Morello (UCL, UK), G. Tinetti (UCL, UK), E. J. Barton (UCL, UK), S. N. Yurchenko (UCL, UK), J. Tennyson (UCL, UK).
University College London was founded in 1826. It was the first English university established after Oxford and Cambridge, the first to open up university education to those previously excluded from it, and the first to provide systematic teaching of law, architecture and medicine. UCL is among the world’s top universities, as reflected by performance in a range of international rankings and tables. UCL currently has over 35 000 students from 150 countries and over 11 000 staff.
Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/
Link to science paper: http://arxiv.org/pdf/1511.08901v2.pdf
Release on the Europlanet Media Centre website: http://www.europlanet-eu.org/?p=393
Images, Video, Text, Credits: ESA/M. Kornmesser/Hubble/Mathias Jäger/UCL/Angelos Tsiaras/Giovanna Tinetti/KU Leuven/Olivia Venot.
Publié par Orbiter.ch à 16:27
ESA - Sentinel 3 Mission logo.
16 February 2016
The third ESA-developed satellite carrying four Earth-observing instruments was launched today, ready to provide a ‘bigger picture’ for Europe’s Copernicus environment programme.
The 1150 kg Sentinel-3A satellite was carried into orbit on a Rockot launcher from Plesetsk, Russia, at 17:57 GMT (18:57 CET; 20:57 local time) on 16 February.
After a first burn starting about five minutes after liftoff and a second about 70 min later, Rockot’s upper stage delivered Sentinel-3A into its planned orbit, 815 km above Earth. The satellite separated 79 min into the flight.
The first signal from Sentinel-3A was received after 92 min by the Kiruna station in Sweden. Telemetry links and attitude control were then established by controllers at ESA’s ESOC operations centre in Darmstadt, Germany, allowing them to monitor the health of the satellite.
After the launch and the early orbit phase of three days, controllers will begin checking that all the satellite elements are working and subsequently calibrate the instruments to commission the satellite. The mission is expected to begin operations in five months.
“With the successful launch of Sentinel-3 we are now looking forward to how our teams of experts will steer this mission into its operational life – like they have done the first two satellites of the series,” said ESA Director General Jan Woerner.
Sentinel-3 solar array
“This is another demonstration of the broad range of competence we have at ESA from the early design phase until the operational mission in orbit.”
The mission is the third of six families of dedicated missions that make up the core of Europe’s Copernicus environmental monitoring network. Copernicus relies on the Sentinels and contributing missions to provide data for monitoring the environment and supporting civil security activities. Sentinel-3 carries a series of cutting-edge sensors to do just that.
Over oceans, it measures the temperature, colour and height of the sea surface as well as the thickness of sea ice. These measurements will be used, for example, to monitor changes in Earth’s climate and for more hands-on applications such as marine pollution and biological productivity.
Over land, this innovative mission will monitor wildfires, map the way land is used, check vegetation health and measure the height of rivers and lakes.
“This is the third of the Sentinel satellites launched in the less than two years – and it is certainly a special moment. It also marks a new era for the Copernicus Services, with Sentinel-3 providing a whole range of new data with unprecedented coverage of the oceans,” said the Director of ESA’s Earth Observation Programmes, Volker Liebig.
Sentinel-3B, its twin satellite, is scheduled for launch next year.
Data from all the Sentinels are used worldwide and are free of charge for all users.
Introducing Sentinel-3: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-3/Introducing_Sentinel-3
Thales Alenia Space: http://www.thalesgroup.com/space/
European Commission Copernicus site: http://www.copernicus.eu/
Images, Video, Text, Credits: ESA/Pierre Carril/ATG medialab.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 16:09
NASA - Cassini Mission to Saturn patch.
Feb. 16, 2016
Dione appears cut in two by Saturn's razor-thin rings, seen nearly edge-on in a view from NASA's Cassini spacecraft. This scene was captured from just 0.02 degrees above the ring plane.
The bright streaks of Dione's wispy terrain are seen near the moon's limb at right. The medium-sized crater Turnus (63 miles, 101 kilometers, wide) is visible along Dione's terminator.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 25, 2015. The view was acquired at a distance of approximately 1.4 million miles (2.3 million kilometers) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 115 degrees. Image scale is 8.6 miles (13.8 kilometers) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (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. 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, Colorado.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org and ESA's website: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens
Image, Text, Credits: NASA/JPL-Caltech/Space Science Institute/Tony Greicius.
Publié par Orbiter.ch à 08:17
ESA - LISA Pathfinder Mission patch.
16 February 2016
ESA’s LISA Pathfinder has released both of its gold–platinum cubes, and will shortly begin its demanding science mission, placing these test masses in the most precise freefall ever obtained to demonstrate technologies for observing gravitational waves from space.
Launched on 3 December, LISA Pathfinder reached its operational location on 22 January, some 1.5 million km from Earth in the direction of the Sun.
Freely Floating in space
As tests on the spacecraft and its precious payload continue, a major milestone was reached today. For the first time, the two masses – a pair of identical 46 mm gold–platinum cubes – in the heart of the spacecraft are floating freely, several millimetres from the walls of their housings. The cubes sit 38 cm apart linked only by laser beams.
Throughout LISA Pathfinder’s ground handling, launch, the burns that raised its orbit, and the six-week cruise to its work site, each cube was held firmly in place by eight ‘fingers’ pressing on its corners.
On 3 February, the locking fingers were retracted and a valve was opened to allow any residual gas molecules around the cubes to vent to space.
Each cube remained in the centre of its housing held by a pair of rods softly pushing on two opposite sides.
The rods were finally released from one test mass yesterday and from the other today, leaving the cubes floating freely, with no mechanical contact with the spacecraft.
Test masses inside LISA Pathfinder payload
“This is why we sent the test cubes into space: to recreate conditions that are impossible to achieve in the gravitational field of our planet,” says Paul McNamara, ESA’s project scientist.
“Only under these conditions is it possible to test freefall in the purest achievable form. We can’t wait to start running experiments with this amazing gravity laboratory.”
It will be another week before the cubes are left completely at the mercy of gravity, with no other forces acting on them. Before then, minute electrostatic forces are being applied to move them around and make them follow the spacecraft as its flight through space is slightly perturbed by outside forces such as pressure from sunlight.
On 23 February, the team will switch LISA Pathfinder to science mode for the first time, and the opposite will become true: the cubes will be in freefall and the spacecraft will start sensing any motions towards them owing to external forces. Microthrusters will make minuscule shifts in order to keep the craft centred on one mass.
Inside LISA Pathfinder, with narration
Then the scientists will be in a position to run several months of experiments to determine how accurately the two freely-flying test masses can be kept positioned relative to each other, making measurements with the laser that links them.
Roughly speaking, the required accuracy is on the order of a millionth of a millionth of a metre.
“The release of the test masses was clearly the most critical operation throughout the mission, as it was not possible to test it fully on the ground due to the small forces and movements involved. We are ecstatic with this world-class achievement,” says César García Marirrodriga, ESA’s project manager.
“This is a testament to the innovation and dedication of the large team of people that put together this outstanding space laboratory.”
After final checks, LISA Pathfinder will begin its science mission on 1 March, validating a key technology for observing gravitational waves from space.
Gravitational waves are minute fluctuations in the fabric of spacetime, predicted by Albert Einstein’s general theory of relativity and directly observed for the first time recently by the Laser Interferometer Gravitational-Wave Observatory – an announcement that created a worldwide sensation last week.
As this discovery confirmed, ground-based experiments can detect high-frequency gravitational waves from cosmic events such as the coalescence of a pair of stellar remnants, like neutron stars or black holes. However, to observe lower-frequency gravitational waves emitted by different astronomical sources, such as the merging of supermassive black holes at the centre of large galaxies, it is necessary to move the search into space.
LISA Pathfinder in space
There, a future gravitational wave observatory, already identified as the goal for the L3 mission in ESA’s Cosmic Vision programme, will measure distortions in the fabric of spacetime on the inconceivably tiny scale of a few millionths of a millionth of a metre over a distance of a million kilometres.
“Releasing LISA Pathfinder's test masses is another step forward in gravitational wave astronomy within this memorable month: the test masses are, for the first time, suspended in orbit and subject to measurements,” says Stefano Vitale of University of Trento, Italy, Principal Investigator of the LISA Technology Package.
In the coming months, LISA Pathfinder will verify the fundamental condition needed for a future gravitational wave observatory in space: putting test masses into freefall at unprecedented levels of accuracy, by isolating the two cubes from all external and internal forces except one: gravity. Stay tuned!
About LISA Pathfinder mission: http://sci.esa.int/lisa-pathfinder/
LISA Pathfinder factsheet: http://www.esa.int/Our_Activities/Space_Science/LISA_Pathfinder_factsheet
What is gravity?: http://www.esa.int/Our_Activities/Space_Science/What_is_gravity
Gravitational waves: ‘dents’ in spacetime: http://www.esa.int/Our_Activities/Space_Science/Gravitational_waves_dents_in_spacetime
Images, Video, Text, Credits: ESA/ATG medialab/Markus Bauer/Paul McNamara/César García Marirrodriga/Stefano Vitale.
Best regards, Orbiter.ch
Publié par Orbiter.ch à 05:29
lundi 15 février 2016
ISS - Expedition 46 Mission patch.
February 15, 2016
Two astronauts are wrapping up spacesuit maintenance Thursday Feb. 11, while a variety of human research takes place inside the International Space Station. Outside the station, the 57.7 foot long Canadarm2 robotic arm is being prepared for the upcoming release of a space freighter.
Commander Scott Kelly and astronaut Time Peake from the European Space Agency are finalizing gear replacement work on a U.S. spacesuit today. The spacesuit will be inspected Monday before it is certified for return to service.
Image above: NASA astronaut Scott Kelly works on a spacesuit inside the Quest airlock.
On the life science front, Kelly joined cosmonaut Mikhail Kornienko and NASA astronaut Tim Kopra for eye and heart scans with an ultrasound. The scans are part of the ongoing Ocular Health study seeking to understand visual impairment some astronauts have experienced during their space missions.
Kopra earlier attached sensors to himself for the Sprint study which seeks to reduce muscle and bone loss with new exercise techniques while living in space. Peake collected his own breath sample for the Marrow experiment that observes how microgravity affects bone marrow and blood cells.
Ground controllers are maneuvering the Canadarm2 in position for the Feb. 19 grapple and release of the Orbital ATK Cygnus cargo craft. The Cygnus will be released for a fiery destruction high in the atmosphere over the Pacific Ocean after being attached to the Unity module for over two months.
Ocular Health study: http://www.nasa.gov/mission_pages/station/research/experiments/204.html
Sprint study: http://www.nasa.gov/mission_pages/station/research/experiments/972.html
Orbital ATK Cygnus cargo craft: http://www.nasa.gov/mission_pages/station/structure/launch/orbital.html
International Space Station (ISS): http://www.nasa.gov/mission_pages/station/main/index.html
Space Station Research and Technology: http://www.nasa.gov/mission_pages/station/research/index.html
Image, Text, Credits: NASA/Mark Garcia.
Publié par Orbiter.ch à 15:14