samedi 23 mars 2019

NASA Instruments Image Fireball over Bering Sea

NASA - EOS Terra Mission patch.

March 23, 2019

On Dec. 18, 2018, a large "fireball" - the term used for exceptionally bright meteors that are visible over a wide area - exploded about 16 miles (26 kilometers) above the Bering Sea. The explosion unleashed an estimated 173 kilotons of energy, or more than 10 times the energy of the atomic bomb blast over Hiroshima during World War II.

Animation above: This image sequence from the MISR instrument, aboard the Terra satellite, was taken a few minutes after a meteor exploded over the Bering Sea on Dec. 18. 2018. It shows the shadow of the meteor's trail, and the orange-tinted cloud it left behind. Animation Credits: NASA/GSFC/LaRC/JPL-Caltech, MISR Team.

Two NASA instruments aboard the Terra satellite captured images of the remnants of the large meteor. The image sequence shows views from five of nine cameras on the Multi-angle Imaging SpectroRadiometer (MISR) instrument taken at 23:55 Coordinated Universal Time (UTC), a few minutes after the event. The shadow of the meteor's trail through Earth's atmosphere, cast on the cloud tops and elongated by the low sun angle, is to the northwest. The orange-tinted cloud that the fireball left behind by super-heating the air it passed through can be seen below and to the right of the GIF's center.

The still image, captured by the Moderate Resolution Imaging SpectroRadiometer (MODIS) instrument, is a true-color image showing the remnants of the meteor's passage, seen as a dark shadow cast on thick, white clouds. MODIS captured the image at 23:50 UTC.

Image above: NASA's MODIS instrument, aboard the Terra satellite, captured this true-color image showing the remnants of a meteor's passage, seen as a dark shadow cast on thick, white clouds on Dec. 18, 2018. Image Credits: NASA GSFC.

The Dec. 18 fireball was the most powerful meteor to be observed since 2013; however, given its altitude and the remote area over which it occurred, the object posed no threat to anyone on the ground. Fireball events are actually fairly common and are recorded in the NASA Center for Near Earth Object Studies database.

Artist's concept of Terra satellite. Image Credits: NASA/JPL

The Terra spacecraft was launched in 1999 and is managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland. The MISR instrument was built and is managed by NASA's Jet Propulsion Laboratory in Pasadena, California, for NASA's Science Mission Directorate in Washington. JPL is a division of Caltech. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center in Hampton, Virginia. The MODIS instrument is managed by NASA's Goddard Space Flight Center.

Related article:

An meteor explosion like ten times Hiroshima goes unnoticed

More information about EOS Terra and MISR and MODIS is available at the following site(s):

EOS Terra Satellite:

NASA Center for Near Earth Object Studies database:

Images (mentioned), Animation (mentioned), Text, Credits: NASA/JPL/Esprit Smith/GSFC/Patrick Lynch.


vendredi 22 mars 2019

A “muoscope” with CMS technology

CERN - European Organization for Nuclear Research logo.

22 March, 2019

Particle physicists are experts at seeing invisible things and their detecting techniques have already found many applications in medical imaging or the analysis of art works. Researchers from the CMS experiment at the Large Hadron Collider are developing a new application based on one of the experiment’s particle detectors: a new, small-scale, portable muon telescope, which will allow imaging of visually inaccessible spaces.

Earth’s atmosphere is constantly bombarded by particles arriving from outer space. By interacting with atmospheric matter, they decay into a cascade of new particles, generating a flux of muons, heavier cousins of electrons. These cosmic-ray muons continue their journey towards the Earth’s surface, travelling through almost all material objects.

Image above: The resistive plate chambers (RPC) at CMS are fast gaseous detectors that provide a muon trigger system (Image: CERN).

This “superpower” of muons makes them the perfect partners for seeing through thick walls or other visually challenging subjects. Volcanic eruptions, enigmatic ancient pyramids, underground caves and tunnels: these can all be scanned and explored from the inside using muography, an imaging method using naturally occurring background radiation in the form of cosmic-ray muons. 

Large-area muon telescopes have been developed in recent years for many different applications, some of which use technology developed for the LHC detectors. The muon telescope conceived by CMS researchers from two Belgian universities, Ghent University and the Catholic University of Louvain, is compact and light and therefore easy to transport. It is nonetheless able to perform muography at high resolution. It will be the first spin-off for muography using the CMS Resistive Plate Chambers (RPC) technology. A first prototype of the telescope, also baptised a “muoscope”, has been built with four RPC planes with an active area of 16x16 cm. The same prototype was used in the “UCL to Mars” project; it was tested for its robustness in a simulation of Mars-like conditions in the Utah Desert, where it operated for one month and later came back fully functional.

Other CMS technologies have been used in muon tomography for security and environmental protection, as well as for homeland security.

Learn more about the muon telescope here:


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.

CERN, the European Organization for Nuclear Research, is one of the world's leading laboratories for particle physics. The Organization is located on the French-Swiss border, with its headquarters in Geneva. Its Member States are: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Spain, Sweden, Switzerland and United Kingdom. Cyprus, Serbia and Slovenia are Associate Member States in the pre-stage to Membership. India, Lithuania, Pakistan, Turkey and Ukraine are Associate Member States. The European Union, Japan, JINR, the Russian Federation, UNESCO and the United States of America currently have Observer status.

Related links:

UCL to Mars:

Security and environmental protection:

Homeland security:

For more information about European Organization for Nuclear Research (CERN), Visit:

Image (mentioned), Text, Credits: CERN/Cristina Agrigoroae.

Best regards,

Galactic Center Visualization Delivers Star Power

NASA - Chandra X-ray Observatory patch.

March 22, 2019

Galactic Center 360-degree Visualization

Video above: A new immersive, 360-degree, ultra-high-definition visualization allows viewers to view the center of our Galaxy as if they were sitting in the position of the Milky Way’s supermassive black hole (Sgr A*). By combining supercomputer simulations with Chandra data, the visualization shows the effects of dozens of massive stellar giants with fierce winds blowing off their surfaces in the region covering a few light years surrounding Sgr A*. Blue and cyan represent X-ray emission from hot gas with temperatures of tens of millions of degrees, while the red emission shows ultraviolet emission from moderately dense regions of cooler gas with temperatures of tens of thousands of degrees, and yellow shows the cooler gas with the highest densities. Video Credits: NASA/CXC/Pontifical Catholic Univ. of Chile /C.Russell et al.

Want to take a trip to the center of the Milky Way? Check out a new immersive, ultra-high-definition visualization. This 360-movie offers an unparalleled opportunity to look around the center of the galaxy, from the vantage point of the central supermassive black hole, in any direction the user chooses.

By combining NASA Ames supercomputer simulations with data from NASA's Chandra X-ray Observatory, this visualization provides a new perspective of what is happening in and around the center of the Milky Way. It shows the effects of dozens of massive stellar giants with fierce winds blowing off their surfaces in the region a few light years away from the supermassive black hole known as Sagittarius A* (Sgr A* for short).

Image above: Extensive observations with Chandra of the central regions of the Milky Way have provided critical data about the temperature and distribution of this multimillion-degree gas. Image Credits: X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI.

These winds provide a buffet of material for the supermassive black hole to potentially feed upon. As in a previous visualization, the viewer can observe dense clumps of material streaming toward Sgr A*. These clumps formed when winds from the massive stars near Sgr A* collide. Along with watching the motion of these clumps, viewers can watch as relatively low-density gas falls toward Sgr A*. In this new visualization, the blue and cyan colors represent X-ray emission from hot gas, with temperatures of tens of millions of degrees; red shows ultraviolet emission from moderately dense regions of cooler gas, with temperatures of tens of thousands of degrees; and yellow shows of the cooler gas with the highest densities.

A collection of X-ray-emitting gas is seen to move slowly when it is far away from Sgr A*, and then pick up speed and whip around the viewer as it comes inwards. Sometimes clumps of gas will collide with gas ejected by other stars, resulting in a flash of X-rays when the gas is heated up, and then it quickly cools down. Farther away from the viewer, the movie also shows collisions of fast stellar winds producing X-rays. These collisions are thought to provide the dominant source of hot gas that is seen by Chandra.

When an outburst occurs from gas very near the black hole, the ejected gas collides with material flowing away from the massive stars in winds, pushing this material backwards and causing it to glow in X-rays. When the outburst dies down the winds return to normal and the X-rays fade.

Chandra X-ray Observatory. Image Credits: NASA/CXC

The 360-degree video of the Galactic Center is ideally viewed through virtual reality (VR) goggles, such as Samsung Gear VR or Google Cardboard. The video can also be viewed on smartphones using the YouTube app. Moving the phone around reveals a different portion of the movie, mimicking the effect in the VR goggles. Finally, most browsers on a computer also allow 360-degree videos to be shown on YouTube. To look around, either click and drag the video, or click the direction pad in the corner.

Dr. Christopher Russell of the Pontificia Universidad Católica de Chile (Pontifical Catholic University) presented the new visualization at the 17th meeting of the High-Energy Astrophysics (HEAD) of the American Astronomical Society held in Monterey, Calif. 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:

For more Chandra images, multimedia and related materials, visit:

Video (mentioned), Images (mentioned), Text, Credits: NASA/Lee Mohon/Marshall Space Flight Center/Molly Porter.


Hubble Captures the Brilliant Heart of a Massive Galaxy

NASA - Hubble Space Telescope patch.

March 22, 2019

This fuzzy orb of light is a giant elliptical galaxy filled with an incredible 200 billion stars. Unlike spiral galaxies, which have a well-defined structure and boast picturesque spiral arms, elliptical galaxies appear fairly smooth and featureless. This is likely why this galaxy, named Messier 49 (M49), was discovered by French astronomer Charles Messier in 1771. At a distance of 56 million light-years and measuring 157,000 light-years across, M49 was the first member of the Virgo Cluster of galaxies to be discovered, and it is more luminous than any other galaxy at its distance or nearer.

Elliptical galaxies tend to contain a larger portion of older stars than spiral galaxies and also lack young, blue stars. Messier 49 itself is very yellow, which indicates that the stars within it are mostly older and redder than the Sun. In fact, the last major episode of star formation within the galaxy was about six billion years ago — before the Sun was even born!

Messier 49 is also rich in globular star clusters; it hosts about 6,000 — a number that dwarfs the 150 found in and around the Milky Way. On average, these clusters are 10 billion years old. Messier 49 is also known to host a supermassive black hole at its center with the mass of more than 500 million Suns, identifiable by the X-rays pouring out from the heart of the galaxy. (As this Hubble image comprises optical and infrared observations, these X-rays are not visible here.)

Messier 49 is featured in Hubble’s Messier catalog, which includes some of the most fascinating objects that can be observed from Earth’s Northern Hemisphere. See the NASA-processed image and other Messier objects at:

Hubble Space Telescope (HST)

For more information about Hubble, visit:

Image, Animation, Credit: ESA/Hubble & NASA, J. Blakenslee, P. Cote et al./Text Credit: European Space Agency (ESA)/NASA/Karl Hille.


Spacewalkers Complete Battery Swaps for Station Power Upgrades

ISS - Expedition 59 Mission patch / EVA - Extra Vehicular Activities patch.

March 22, 2019

Expedition 59 Flight Engineers Nick Hague and Anne McClain of NASA concluded their spacewalk at 2:40 p.m. EDT. During the six-hour, 39-minute spacewalk, the two NASA astronauts successfully replaced nickel-hydrogen batteries with newer, more powerful lithium-ion batteries for the power channel on one pair of the station’s solar arrays.

Astronauts were also able to accomplish several get-ahead tasks including removing debris from outside of the station, securing a tieback for restraints on the Solar Array Blanket Box, and photographing a bag of tools for contingency repairs and the airlock thermal cover that is opened and closed for spacewalks.

Image above: NASA astronauts Nick Hague (top) and Anne McClain work to swap batteries in the Port-4 truss structure during today’s spacewalk. Image Credit: NASA TV.

These new batteries provide an improved power capacity for operations with a lighter mass and a smaller volume than the nickel-hydrogen batteries. Next week, McClain and flight engineer Christina Koch are scheduled to venture outside on the March 29 spacewalk to work on a second set of battery replacements on a different power channel in the same area of the station. This would be the first-ever spacewalk with all-female spacewalkers.

Hague and David Saint-Jacques of the Canadian Space Agency are scheduled to conduct a third spacewalk April 8 to lay out jumper cables between the Unity module and the S0 truss, at the midpoint of the station’s backbone. This work will establish a redundant path of power to the Canadian-built robotic arm, known as Canadarm2. They also will install cables to provide for more expansive wireless communications coverage outside the orbital complex, as well as for enhanced hardwired computer network capability.

A Spacewalk Outside The International Space Station on This Week @NASA – March 22, 2019

Space station crew members have conducted 214 spacewalks in support of assembly and maintenance of the orbiting laboratory. This was the first spacewalk for both McClain and Hague. Spacewalkers have now spent a total of 55 days, 21 hours and 39 minutes working outside the station.

Related links:

Expedition 59:


Space Station Research and Technology:

International Space Station (ISS):

Image (mentioned), Video (NASA), Text, Credits: NASA/Mark Garcia.

Best regards,

Water in space

ISS - International Space Station logo.

22 March 2019

Did you know that up to 80% of the water on the International Space Station is recycled? Astronauts living and working 400 km above our planet might prefer not to think about it, but the water they drink is recycled from their colleague’s sweat and exhaled breath – collected as condensation on the Space Station’s walls.

Samantha Cristoforetti with water on Space Station

Water is precious on Earth but even more so in space where all drinkable water must be transported from home or recycled. As water is a dense and heavy substance it takes a lot of energy to propel it into space – there is only so much a rocket can carry so the less water we send, the more scientific equipment can be sent in its place. This is one of the reasons why there is no shower on the International Space Station – astronauts wash themselves only with wet-wipes for six months! Astronauts in space often list fresh fruit and a shower as the things they miss most from Earth.

As we explore further from our home planet providing water and food to astronauts will become more and more challenging so just like on Earth reduce, reuse, and recycle is the mantra for off-world explorers and their space agencies.

For over thirty years the European Space Agency and partner universities have been working to develop a self-sustained eco-system in a box that astronauts could take with them on a spacecraft to explore our Solar System. Endlessly recycling waste such as urine and sweat, the system uses a chain of filters, bacteria in bioreactors and chemical reactions to produce clean water and food. The goal is to become completely self-sufficient so astronauts could travel through deep space forever producing the three basic elements of life: water, oxygen and food.

A view inside the MELiSSA pilot plant at the University Autònoma of Barcelona

The European Space Agency is testing a closed-loop life-support system in Barcelona, Spain, to support a number of rats indefinitely in a comfortable habitat – a complete ecosystem shut off from our environment created with one purpose: to keep the rats healthy and happy.

Astronaut Pedro Duque through a water drop

We are not there yet, but in its thirty years the team working on this project, dubbed Melissa, has come a long way and its processes are providing clean drinking water for universities, hotels, monks and researchers in Antarctica. If it is designed for spaceflight it will almost certainly work anywhere in the world – and the goal of clean water and food through recycling is shared by all.

Related links:

International Space Station (ISS):

European space laboratory Columbus:

International Space Station Benefits for Humanity:

Images, Text, Credits: ESA/NASA/UAB.

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Arianespace’s Vega success with PRISMA in numbers: 3 + 14 + 308 = 600!

Arianespace - Vega Flight VV14 Mission poster.

March 22, 2019

Image above: Vega begins its ascent from the Spaceport in French Guiana, carrying Italy’s PRISMA Earth observation satellite on the third Arianespace mission of 2019.

Vega launches PRISMA

An Arianespace Vega launch vehicle (Flight VV14) launched the PRISMA Earth observation satellite from the Vega Launch Complex (SLV) in Kourou, French Guiana, on 22 March 2019, at 01:50:35 UTC (21 March, at 22:50:35 local time).

PRISMA satellite deployment

Arianespace’s third mission of 2019 – which marked the Vega rocket’s 14th consecutive success – orbited the Italian PRISMA Earth observation satellite tonight, bringing the total number of spacecraft lofted by the launch services company to 600. It was the 308th flight overall of an Arianespace launcher.

PRISMA satellite

PRISMA (PRecursore IperSpettrale della Missione Applicativa) was produced for the Italian ASI space agency by OHB Italia as prime contractor, with Leonardo responsible for the Earth observation system. Operating from low Earth orbit, the satellite is designed to provide major applications for protection of the planet and for Italy’s national environmental safety. It is equipped with a state-of-the-art electro-optical instrument with a medium-resolution camera and an innovative hyperspectral sensor. Once operational, PRISMA will provide data for environmental monitoring, resources management, the identification and classification of crops, the fight against pollution and other uses.

More information about Arianespace, visit:

Images, Videos, Text, Credits: Arianespace/SciNews.


jeudi 21 mars 2019

Final Suit Checks and Reviews before Friday’s Spacewalk

ISS - Expedition 59 Mission patch.

March 21, 2019

Two Expedition 59 astronauts are checking their spacesuits today and reviewing procedures one final time before tomorrow’s spacewalk. The other four residents aboard the International Space Station assisted the spacewalkers, maintained the orbital lab and conducted space science.

NASA Flight Engineers Anne McClain and Nick Hague readied the Quest airlock today where they will begin the first spacewalk of 2019 Friday at 8:05 a.m. EDT. The spacewalkers will work outside for about 6.5 hours of battery upgrade work on the Port-4 truss structure. NASA TV begins its live spacewalk coverage at 6:30 a.m.

NASA experts discuss the upcoming power upgrade spacewalks

The duo also confirmed their U.S. spacesuits are ready for the excursion with all the necessary components, such as helmet lights and communications gear, installed. Afterward, Hague and McClain conducted one more spacewalk timeline review.

They then joined astronauts Christina Koch and David Saint-Jacques for a final conference with spacewalk experts in Mission Control. Both astronauts also charged and set up GoPro cameras before attaching them to the spacewalkers’ suit helmets.

Image above: NASA astronaut Anne McClain assists fellow NASA astronauts Christina Koch (left) and Nick Hague as they verify their U.S. spacesuits are sized correctly and fit properly ahead of a set of upcoming spacewalks. Image Credit: NASA.

Koch started her day cleaning ventilation screens in the Unity module and installing lights in the Permanent Multi-purpose Module. Saint-Jacques set up the AstroPi science education hardware in the Harmony module’s window then swapped fan cables in the Life Sciences Glovebox.

Commander Oleg Kononenko and fellow cosmonaut Alexey Ovchinin spent the majority of their day in the station’s Russian segment. Kononenko and Ovchinin first collected and stowed their blood samples in a science freezer for a Russian metabolism experiment. Ovchinin then unpacked supplies from the recently arrived Soyuz MS-12 crew ship. Kononenko also worked on heart and radiation detection research before assisting the U.S. spacewalkers.

Related links:


Expedition 59:

Quest airlock:

Port-4 truss structure:

Unity module:

Permanent Multi-purpose Module:


Harmony module:

Life Sciences Glovebox:

Space Station Research and Technology:

International Space Station (ISS):

Image (mentioned), Video (NASA), Text, Credits: NASA/Mark Garcia.

Best regards,

Jupiter Marble

NASA - JUNO Mission logo.

March 21, 2019

This striking view of Jupiter's Great Red Spot and turbulent southern hemisphere was captured by NASA's Juno spacecraft as it performed a close pass of the gas giant planet.

Juno took the three images used to produce this color-enhanced view on Feb. 12, 2019, between 9:59 a.m. PST (12:59 p.m. EST) and 10:39 p.m. PST (1:39 p.m. EST), as the spacecraft performed its 17th science pass of Jupiter. At the time the images were taken, the spacecraft was between 16,700 miles (26,900 kilometers) and 59,300 miles (95,400 kilometers) above Jupiter's cloud tops, above a southern latitude spanning from about 40 to 74 degrees.

Citizen scientist Kevin M. Gill created this image using data from the spacecraft's JunoCam imager.

JunoCam's raw images are available at for the public to peruse and process into image products.

More information about Juno is online at and

JUNO spacecraft orbiting Jupiter

NASA's Jet Propulsion Laboratory manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. Caltech in Pasadena, California, manages JPL for NASA.

Image, Animation, Text, Credits: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill.


LHCb sees a new flavour of matter–antimatter asymmetry

CERN - European Organization for Nuclear Research logo.

March 21, 2019

The LHCb collaboration has observed a phenomenon known as CP violation in the decays of a particle known as a D0 meson for the first time 

Image above: A CP-symmetry transformation swaps a particle with the mirror image of its antiparticle. The LHCb collaboration has observed a breakdown of this symmetry in the decays of the D0 meson (illustrated by the big sphere on the right) and its antimatter counterpart, the anti-D0 (big sphere on the left), into other particles (smaller spheres). The extent of the breakdown was deduced from the difference in the number of decays in each case (vertical bars, for illustration only) (Image: CERN).

The LHCb collaboration at CERN1 has seen, for the first time, the matter–antimatter asymmetry known as CP violation in a particle dubbed the D0 meson. The finding, presented today at the annual Rencontres de Moriond conference and in a dedicated CERN seminar, is sure to make it into the textbooks of particle physics.

“The result is a milestone in the history of particle physics. Ever since the discovery of the D meson more than 40 years ago, particle physicists have suspected that CP violation also occurs in this system, but it was only now, using essentially the full data sample collected by the experiment, that the LHCb collaboration has finally been able to observe the effect,” said CERN Director for Research and Computing, Eckhard Elsen.

The term CP refers to the transformation that swaps a particle with the mirror image of its antiparticle. The weak interactions of the Standard Model of particle physics are known to induce a difference in the behaviour of some particles and of their CP counterparts, an asymmetry known as CP violation. The effect was first observed in the 1960s at Brookhaven Laboratory in the US in particles called neutral K mesons, which contain a “strange quark”, and, in 2001, experiments at the SLAC laboratory in the US and the KEK laboratory in Japan also observed the phenomenon in neutral B mesons, which contain a “bottom quark”. These findings led to the attribution of two Nobel prizes in physics, one in 1980 and another in 2008.

CP violation is an essential feature of our universe, necessary to induce the processes that, following the Big Bang, established the abundance of matter over antimatter that we observe in the present-day universe. The size of CP violation observed so far in Standard Model interactions, however, is too small to account for the present-day matter–antimatter imbalance, suggesting the existence of additional as-yet-unknown sources of CP violation.

The D0 meson is made of a charm quark and an up antiquark. So far, CP violation has only been observed in particles containing a strange or a bottom quark. These observations have confirmed the pattern of CP violation described in the Standard Model by the so-called Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix, which characterises how quarks of different types transform into each other via weak interactions. The deep origin of the CKM matrix, and the quest for additional sources and manifestations of CP violation, are among the big open questions of particle physics. The discovery of CP violation in the D0 meson is the first evidence of this asymmetry for the charm quark, adding new elements to the exploration of these questions.

To observe this CP asymmetry, the LHCb researchers used the full dataset delivered by the Large Hadron Collider (LHC) to the LHCb experiment between 2011 and 2018 to look for decays of the D0 meson and its antiparticle, the anti-D0, into either kaons or pions. “Looking for these two decay products in our unprecedented sample of D0 particles gave us the required sensitivity to measure the tiny amount of CP violation expected for such decays. Measuring the extent of the violation then boiled down to counting the D0 and anti-D0 decays and taking the difference,” explained Giovanni Passaleva, spokesperson for the LHCb collaboration.

The result has a statistical significance of 5.3 standard deviations, exceeding the threshold of 5 standard deviations used by particle physicists to claim a discovery. This measurement will stimulate renewed theoretical work to assess its impact on the CKM description of CP violation built into the Standard Model, and will open the window to the search for possible new sources of CP violation using charmed particles.


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.

CERN, the European Organization for Nuclear Research, is one of the world's leading laboratories for particle physics. The Organization is located on the French-Swiss border, with its headquarters in Geneva. Its Member States are: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Spain, Sweden, Switzerland and United Kingdom. Cyprus, Serbia and Slovenia are Associate Member States in the pre-stage to Membership. India, Lithuania, Pakistan, Turkey and Ukraine are Associate Member States. The European Union, Japan, JINR, the Russian Federation, UNESCO and the United States of America currently have Observer status.

Related links:

Rencontres de Moriond:

CERN seminar:

Standard Model of particle physics:



LHCb paper:

For more information about European Organization for Nuclear Research (CERN), Visit:

Image (mentioned), Text, Credits: CERN.

Best regards,

Land-cover dynamics unveiled

ESA - Sentinel-2 Mission logo.

21 March 2019

Billions of image pixels recorded by the Copernicus Sentinel-2 mission have been used to generate a high-resolution map of land-cover dynamics across Earth’s landmasses. This map also depicts the month of the peak of vegetation and gives new insight into land productivity.

 Land-cover map

Using three years’ worth of optical data, the map can indicate the time of vegetation peak and variability of vegetation across seasons. Developed by GeoVille, an Austrian company specialised in the analysis of satellite data, this land-cover map dynamics map uses Copernicus Sentinel-2 archive data from 2015-18, and gives a complete picture of variations of vegetation. The map is displayed at a resolution of 20 m, however a 10 m version is available on request.

It can, for example, support experts working with land-cover classification and can serve as input for services in areas such as agriculture, forestry and land-degradation assessments.

“In particular, we use this as a basis to develop services for the agrofood industry and farmers growing potatoes and other crops, as well as information on how vegetation changes over the year,” explains Eva Haas, Head of GeoVille’s Agricultural Unit.

Swamps and lakes in West Africa

The land-cover dynamic layer was produced with GeoVille’s processing engine LandMonitoring.Earth, a fully-automated land-monitoring system built on data streams from the Copernicus Sentinel-1 and Sentinel-2 missions, as well as ESA third party missions such as the US Landsat.

“Using the system, we processed the complete Copernicus Sentinel-2 image archive along with artificial intelligence, machine learning and big data analytics,” explains Michael Riffler, Head of Research and Development at GeoVille.


“However, the key is the dense time-series of the Copernicus Sentinel-2 data which allows this information to be retrieved for the first time. To date, we have processed more than 23 billion pixels.”

The development has been done through ESA’s Earth observation innovation hub – ɸ-lab, and has been implemented by GeoVille and its subsidiary in the Netherlands – GEO4A.

Crops in the Netherlands

“This map forms an excellent foundation for other – more specialised – land cover classifications, whose development and deployment can be further accelerated by applying machine learning and AI,” says Iarla Kilbane-Dawe, the head of ESA’s Φ-Lab in Frascati, Italy.

The LandMonitoring.Earth system is designed to efficiently implement major client solutions such as the European Copernicus Land Monitoring Service products. Experts can specify desired land monitoring data for any place on the globe for any given time period, and receive a quality-controlled output, depending on the required geographic coverage and frequency.

The idea is to make information available to non-experts along with the specific resources and tools that they need.

Related links:


Land Monitoring Earth Portal:



Images, Text, Credits: ESA/Contains modified Copernicus Sentinel data (2016–18), processed by GeoVille.


mercredi 20 mars 2019

Watch the Skies: Happy Equinox!

Astronomy logo.

March 20, 2019

Happy equinox, Earthlings! March 20 marks the spring equinox, one of two seasonal markers in Earth’s year-long orbit when the Sun appears to shine directly over the equator, and daytime and nighttime are nearly equal lengths–12 hours–everywhere on the planet.

Image above: During the equinoxes, both hemispheres receive equal amounts of daylight. (Image not to scale.) Image Credits: NASA/GSFC/Genna Duberstein.

It’s the start of astronomical spring in the Northern Hemisphere, meaning more sunlight and longer days. From here until the beginning of fall, daytime will be longer than nighttime as the Sun travels a longer, higher arc across the sky each day, reaching a peak at the start of summer. It’s just the opposite in the Southern Hemisphere, where March 20 marks the fall equinox.

What’s more? The first full Moon of spring will rise tonight, lighting the skies on the equinox. Usually, a full Moon arrives a few days to weeks before or after the equinox. It’s close, but not a perfect match. Tonight’s full Moon, however, reaches maximum illumination less than four hours after the equinox. There hasn’t been a comparable coincidence since the spring equinox in 2000.

Image above: When the Moon, on its orbit around Earth, reaches the point farthest from the Sun, we see a full Moon. Image Credits: NASA/GSFC/Genna Duberstein.

And because the Moon is near perigee, it qualifies as a supermoon–the third and final of 2019. It’s not a big supermoon, so you won’t really be able to see the difference between this full Moon and any other one with your eyes. But keep an keep an eye on the Moon as it rises and creeps above the eastern skyline. A low-hanging Moon can appear strangely inflated. This is the Moon illusion at work.

Super or seemingly not, it’s a rare celestial coincidence to usher in springtime.

Watch the Skies:

Images (mentioned), Text, Credits: NASA/Lee Mohon.


Astronauts Gear Up for Spacewalk and Get Up to Date on Station Safety

ISS - Expedition 59 Mission patch.

March 20, 2019

The Expedition 59 crew is busy preparing for the first spacewalk of 2019 set to begin in just two days. Meanwhile, the orbital residents are still exploring the effects of space on their bodies while familiarizing themselves with emergency hardware.

NASA astronauts Nick Hague and Anne McClain continued organizing their tools this morning ahead of Friday morning’s spacewalk. The duo will enter the Quest module’s crew airlock and their spacesuits will go on battery power Friday around 8:05 a.m. EDT signaling the beginning of the spacewalk.

Expedition 59 EVA 52 & 53 Briefing March 19, 2019

Video above:: NASA experts discuss the upcoming power upgrade spacewalks. Video Credit: NASA.

Hague and McClain will spend about six-and-a-half hours upgrading the International Space Station’s storage capacity. They will swap out old nickel-hydrogen batteries with new lithium-ion batteries and install battery adapter plates on the Port-4 truss structure. NASA TV begins its live space coverage Friday at 6:30 a.m.

Image above: NASA astronaut and Expedition 59 Flight Engineer Christina Koch familiarizes herself with International Space Station hardware inside the Unity module. Image Credits: NASA/JSC.

Hague started Wednesday, however, in the Columbus lab module helping scientists understand how microgravity impacts the perception of time. McClain collected light measurements in the afternoon from two laboratory modules and the Quest airlock to document how new station LED lights affect crew wellness.

The station’s latest crew arrivals spent a couple of hours Wednesday morning checking out safety and communications gear. Hague along with Flight Engineers Christina Koch and Alexey Ovchinin split their time between the station’s U.S. and Russian segments looking at emergency hardware and procedures.

Image above: A waxing gibbous Moon is seen above Earth's limb as the International Space Station was orbiting 266 miles above the South Atlantic Ocean. The term “supermoon” was coined in 1979 and is used to describe what astronomers would call a perigean (pear-ih-jee-un) full moon: a full Moon occurring near or at the time when the Moon is at its closest point in its orbit around Earth. Tonight's supermoon is the third and final supermoon of 2019. The first was on Jan. 21, and the second was on Feb. 19. In this image, the Moon is waxing or growing bigger. Gibbous means that it is less than a full Moon, but larger than the Moon's shape in its third quarter. Image Credit: NASA.

Related links:

Expedition 59:


Quest module:

Port-4 truss structure:


Columbus lab module:

Perception of time:

Light measurements:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Video (mentioned), Text, Credits: NASA/Mark Garcia/Yvette Smith.

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Giant ‘chimneys’ vent X-rays from Milky Way’s core

ESA - XMM-Newton Mission patch.

20 March 2019

By surveying the centre of our Galaxy, ESA’s XMM-Newton has discovered two colossal ‘chimneys’ funneling material from the vicinity of the Milky Way’s supermassive black hole into two huge cosmic bubbles.

The giant bubbles were discovered in 2010 by NASA’s Fermi Gamma-ray Space Telescope: one stretches above the plane of the Milky Way galaxy and the other below, forming a shape akin to a colossal hourglass that spans about 50 000 light years – around half the diameter of the entire Galaxy. They can be thought of as giant ‘burps’ of material from the central regions of our Milky Way, where its central black hole, known as Sagittarius A*, resides.

Galactic chimneys and bubbles

Now, XMM-Newton has discovered two channels of hot, X-ray emitting material streaming outwards from Sagittarius A*, finally linking the immediate surroundings of the black hole and the bubbles together.

“We know that outflows and winds of material and energy emanating from a galaxy are crucial in sculpting and altering that galaxy’s shape over time – they are key players in how galaxies and other structures form and evolve throughout the cosmos,” says lead author Gabriele Ponti of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and the National Institute for Astrophysics in Italy.

“Luckily, our Galaxy gives us a nearby laboratory to explore this in detail, and probe how material flows out into the space around us. We used data gathered by XMM-Newton between 2016 and 2018 to form the most extensive X-ray map ever made of the Milky Way’s core.”

This map revealed long channels of super-heated gas, each extending for hundreds of light years, streaming above and below the plane of the Milky Way.

Scientists think that these act as a set of exhaust pipes through which energy and mass are transported from our Galaxy’s heart out to the base of the bubbles, replenishing them with new material.

This finding clarifies how the activity occurring at the core of our home Galaxy, both present and past, is connected to the existence of larger structures around it.

XMM-Newton view

The outflow might be a remnant from our Galaxy’s past, from a period when activity was far more prevalent and powerful, or it may prove that even ‘quiescent’ galaxies – those that host a relatively quiet supermassive black hole and moderate levels of star formation like the Milky Way – can boast huge, energetic outflows of material.

“The Milky Way is seen as a kind of prototype for a standard spiral galaxy,” says co-author Mark Morris of the University of California, Los Angeles, USA.

“In a sense, this finding sheds light on how all typical spiral galaxies – and their contents – may behave across the cosmos.”

Outflows from the core of the Galaxy

Despite its categorisation as quiescent on the cosmic scale of galactic activity, previous data from XMM-Newton have revealed that our Galaxy’s core is still quite tumultuous and chaotic. Dying stars explode violently, throwing their material out into space; binary stars whirl around one another; and Sagittarius A*, a black hole as massive as four million Suns, lies in wait for incoming material to devour, later belching out radiation and energetic particles as it does so.

Cosmic behemoths such as Sagittarius A* – and those even more massive – hosted by galaxies across the cosmos will be explored in depth by upcoming X-ray observatories like ESA’s Athena, the Advanced Telescope for High-Energy Astrophysics, scheduled for launch in 2031. Another future ESA mission, Lisa, the Laser Interferometer Space Antenna, will search for gravitational waves released by the merger of supermassive black holes at the core of distant, merging galaxies.

Meanwhile, scientists are busy investigating these black holes with current missions like XMM-Newton.

“There’s still a great deal to be done with XMM-Newton – the telescope could scan a significantly larger region of the Milky Way’s core, which would help us to map the bubbles and hot gas surrounding our Galaxy as well as their connections to the other components of the Milky Way, and hopefully figure out how all of this is linked together,” adds Gabriele.

“Of course, we’re also looking forward to Athena and the breakthrough it will enable.”


Athena will combine extremely high-resolution X-ray spectroscopy with excellent imaging capabilities over wide areas of the sky, allowing scientists to probe the nature and movement of hot cosmic gas like never before.

“This outstanding result from XMM-Newton gives us an unprecedented view of what’s really happening at the core of the Milky Way, and presents the most extensive X-ray map ever created of the entire central region,” says ESA XMM-Newton Project Scientist Norbert Schartel.

“This is especially exciting in the context of our upcoming missions. XMM-Newton is paving the way for the future generation of X-ray observatories, opening up abundant opportunities for these powerful spacecraft to make substantial new discoveries about our Universe.”

Notes for editors:

“An X-ray Chimney extending hundreds of parsecs above and below the Galactic Centre” by G. Ponti et al. is published in the journal Nature:

XMM-Newton data were used in conjunction with archival data from NASA’s Chandra X-Ray Observatory.

The bubbles stretching above and below the Milky Way’s disc are known as Fermi bubbles, and were discovered in gamma-ray data gathered by NASA's Fermi Gamma-ray Space Telescope in 2010.

Related links:


NASA’s Chandra X-Ray Observatory:

NASA's Fermi Gamma-ray Space Telescope:

Images, Text, Credits: ESA/Markus Bauer/Norbert Schartel/University of California/Mark Morris/Max Planck Institute for Extraterrestrial Physics/INAF Brera Astronomical Observatory/Gabriele Ponti/XMM-Newton/G. Ponti et al. 2019; ESA/C. Carreau/Gaia/DPAC (Milky Way map), CC BY-SA 3.0 IGO/Nature.


Taking gravity from strength to strength

ESA - GOCE Mission logo.

20 March 2019

Ten years ago, ESA launched one of its most innovative satellites. GOCE spent four years measuring a fundamental force of nature: gravity. This extraordinary mission not only yielded new insights into our gravity field, but led to some amazing discoveries about our planet, from deep below the surface to high up in the atmosphere and beyond. And, this remarkable mission continues to realise new science today.


Because of factors such as the planet’s rotation, the position of mountains and ocean trenches and different densities in materials in Earth’s interior, the force of gravity at Earth’s surface varies from place to place.

Mapping these differences is important for measuring ocean circulation, sea-level change and for understanding otherwise hidden processes occurring deep inside the planet, for example.

Orbiting as close to Earth as possible, GOCE mapped these subtle variations with extreme detail and accuracy.

Just two years after it was launched, GOCE had gathered enough data to map our gravity field with unrivalled precision, resulting in the most accurate model of the ‘geoid’ – the surface of an ideal global ocean at rest.

In fact GOCE’s four years in orbit resulted in a series of gravity models, each more accurate than the last. And, importantly, yet another even more accurate model will soon be released to the public.

The shape of gravity

ESA’s GOCE mission manager, Rune Floberghagen, said, “GOCE was a true marvel, both technically and scientifically. Experts are again revisiting the data and using some very clever techniques to regenerate another gravity model that’s 20% more accurate than the last, and which we intend to present in May.”

Since it was launched, scientists all over the world have been using GOCE data to discover more about our planet.

For instance, by combining the new GOCE models with satellite altimetry data, which give the actual height of the sea surface, the difference between the geoid height and the sea-surface height can be found.

This is revealing greater insight into currents such as the Gulf Stream, different branches of the North Atlantic Current, the Kuroshio in the north Pacific, and the Antarctic circumpolar current.

While the GOCE geoid is being used to understand how oceans transport huge quantities of heat around the planet and used to develop a global height reference system, the mission’s gravity-field measurements are also shedding new light on Earth’s interior.

1993–2011 ocean currents

Geophysicists are using GOCE gravity gradient measurements to gain, for example, new insights into the geodynamics associated with the lithosphere. GOCE has also been used to produce the first global high-resolution map of the boundary between Earth’s crust and mantle – the Moho, offering new clues into the dynamics of Earth’s interior.

It has also given us a new view of the remnants of lost continents hidden deep under the ice sheet of Antarctica.

And, although it was not designed to map changes in gravity over time, ice being lost from parts of Antarctica was mirrored in GOCE’s measurements, helping scientists to better understand glacial dynamics.

GOCE went on to become the first seismometer in orbit when it detected sound waves from the massive earthquake that hit Japan in March 2011. Never before had sound waves from a quake been sensed directly in space.

GOCE reveals Antarctic tectonics

And, thanks to its exceptional low orbit and ion engine that responded to tiny changes in air drag, scientists were also able to use its thruster and accelerometer measurements to create a completely new dataset of upper atmosphere densities and wind speeds.

While these are just some of GOCE’s scientific success stories, the satellite’s sleek design, its gradiometer instrument and sophisticated electric propulsion were all firsts in the history of satellite technology.

Danilo Muzi, ESA’s Earth Explorers Programme Manager, said, “GOCE was the epitome of an ESA Earth Explorer. Each of these research missions uses completely new technology to deliver information that fills gaps in our knowledge of how our world functions.

“It was a remarkable success in terms of science and also in terms of technology. More than doubling its planned life in orbit and embodying some remarkable firsts, the mission offers sound heritage on which to base future satellite systems.

“GOCE was the first Earth Explorer in orbit and we are truly proud to have delivered such a ground-breaking mission.

GOCE senses changing gravity

“While GOCE’s life came to a natural end in 2013, we currently have four other Earth Explorer missions in orbit, another three being built and two concepts being assessed – all are unique.

“This family of flagship missions are the most advanced of our time, answering key scientific questions and demonstrating how cutting-edge technology can be used in space – and of which we are extremely proud.”

Related links:


GOCE Virtual Archive:

Image, Videos, Text, Credits: ESA/AOES-Medialab/CNES/CLS.


mardi 19 mars 2019

ATLAS observes light scattering off light

CERN - ATLAS Experiment logo.

19 March, 2019

The ATLAS Collaboration has reported the observation of light-by-light scattering with a significance beyond eight standard deviations 

Image above: An ATLAS event with energy deposits of two photons in the electromagnetic calorimeter (green) on opposite sides and no other activity in the detector, a clean signature of light-by-light scattering. The Feynman diagram of this process is also shown (Image: CERN).

Light-by-light scattering is a very rare phenomenon in which two photons – particles of light – interact, producing again a pair of photons. This process was among the earliest predictions of quantum electrodynamics (QED), the quantum theory of electromagnetism, and is forbidden in classical physics (such as Maxwell’s theory of electrodynamics).

Direct evidence for light-by-light scattering at high energy had proven elusive for decades, until the Large Hadron Collider (LHC) began its second data-taking period (Run 2). Collisions of lead ions in the LHC provide a uniquely clean environment to study light-by-light scattering. The bunches of lead ions that are accelerated to very high energy are surrounded by an enormous flux of photons. When two lead ions pass close by each other at the centre of the ATLAS detector, but with a distance greater than twice the lead-ion radius, those photons can still interact and scatter off one another without any further interaction between the lead ions, as the reach of the (much stronger) strong force is bound to the radius of a single proton. These interactions are known as ultra-peripheral collisions.

Yesterday, at the Rencontres de Moriond conference (La Thuile, Italy), the ATLAS collaboration reported the observation of light-by-light scattering with a significance of 8.2 standard deviations. The result uses data from the most recent heavy-ion operation of the LHC, which took place in November 2018. This new measurement opens the door to further study the light-by-light scattering process, which is not only interesting in itself as a manifestation of an extremely rare QED phenomenon, but may be sensitive to contributions from particles beyond the Standard Model. It allows for a new generation of searches for hypothetical light and neutral particles.

Read more on the ATLAS website:


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.

Related links:

Large Hadron Collider (LHC):

ATLAS detector:

Rencontres de Moriond:

Observation of light-by-light scattering:

For more information about European Organization for Nuclear Research (CERN), Visit:

Image (mentioned), Text, Credit: European Organization for Nuclear Research (CERN).