dimanche 17 juin 2018

Astronomers See Distant Eruption as Black Hole Destroys Star

NASA - Hubble Space Telescope patch / NASA - Spitzer Space Telescope patch.

June 17, 2018

For the first time, astronomers have directly imaged the formation and expansion of a fast-moving jet of material ejected when the powerful gravity of a supermassive black hole ripped apart a star that wandered too close to the massive monster.

The scientists tracked the event with radio and infrared telescopes, including the National Science Foundation's Very Long Baseline Array (VLBA) and NASA's Spitzer Space Telescope, in a pair of colliding galaxies called Arp 299. The galaxies are nearly 150 million light-years from Earth. At the core of one of the galaxies, a black hole 20 million times more massive than the Sun shredded a star more than twice the Sun's mass, setting off a chain of events that revealed important details of the violent encounter. The researchers also used observations of Arp 299 made by NASA's Hubble space telescope prior to and after the appearance of the eruption.

Black Hole vs. Star: A Tidal Disruption Event (Artist's Concept)

Image above: An artist's concept of a tidal disruption event (TDE) that happens when a star passes fatally close to a supermassive black hole, which reacts by launching a relativistic jet. Image Credits: Sophia Dagnello, NRAO/AUI/NSF.

Only a small number of such stellar deaths, called tidal disruption events, or TDEs, have been detected. Theorists have suggested that material pulled from the doomed star forms a rotating disk around the black hole, emitting intense X-rays and visible light, and also launches jets of material outward from the poles of the disk at nearly the speed of light.

"Never before have we been able to directly observe the formation and evolution of a jet from one of these events," said Miguel Perez-Torres, of the Astrophysical Institute of Andalucia in Granada, Spain, and an author on a paper describing the finding.

Discovery of a jet

The first indication came on January 30, 2005, when astronomers using the William Herschel Telescope in the Canary Islands discovered a bright burst of infrared emission coming from the nucleus of one of the colliding galaxies in Arp 299. On July 17, 2005, the VLBA revealed a new, distinct source of radio emission from the same location.

A Tidal Disruption Event in Arp299B

Image above: An image of the galaxy Arp299B, which is undergoing a merging process with Arp299A (the galaxy to the left), captured by NASA's Hubble space telescope. The inset features an artist's illustration of a tidal disruption event (TDE), which occurs when a star passes fatally close to a supermassive black hole. A TDE was recently observed near the center of Arp299B. Image Credits: Sophia Dagnello, NRAO/AUI/NSF; NASA, STScI.

"As time passed, the new object stayed bright at infrared and radio wavelengths, but not in visible light and X-rays," said Seppo Mattila, of the University of Turku in Finland, another author on the new paper. "The most likely explanation is that thick interstellar gas and dust near the galaxy's center absorbed the X-rays and visible light, then re-radiated it as infrared." The researchers used the Nordic Optical Telescope on the Canary Islands and NASA's Spitzer to follow the object's infrared emission.

Continued observations with the VLBA, the European VLBI Network (EVN), and other radio telescopes, carried out over nearly a decade, showed the source of radio emission expanding in one direction, just as expected for a jet. The measured expansion indicated that the material in the jet moved at an average of one-fourth the speed of light. The radio waves are not absorbed by the dust, but pass through it.

These observations used multiple radio-telescope antennas, separated by thousands of miles, to gain the resolving power, or ability to see fine detail, required to detect the expansion of an object so distant.

Monster appetite

Most galaxies have supermassive black holes, containing millions to billions of times the mass of the Sun, at their cores. In a black hole, the mass is so concentrated that its gravitational pull is so strong that not even light can escape. When those supermassive black holes are actively drawing in material from their surroundings, that material forms a rotating disk around the black hole, and super-fast jets of particles are launched outward. This is the phenomenon seen in radio galaxies and quasars.

Image above: A diagram showing the components of the TDE observed in Arp299B. (Not to scale). The supermassive black hole at the center of the galaxy is surrounded by a highly dense medium, and embedded in a dusty torus. Most of the optical and X-ray emissions produced by the event were absorbed, and re-emitted at infrared (IR) wavelengths due to the existence of polar dust. A few months after the detection at IR wavelengths, the TDE was detected at radio wavelengths with the help of a very sensitive array of radio telescopes. Image Credits: Seppo Mattila, Miguel Pérez-Torres et al. 2018 (Science).

"Much of the time, however, supermassive black holes are not actively devouring anything, so they are in a quiet state," Perez-Torres explained. "Tidal disruption events can provide us with a unique opportunity to advance our understanding of the formation and evolution of jets in the vicinities of these powerful objects."

"Because of the dust that absorbed any visible light, this particular tidal disruption event may be just the tip of the iceberg of what until now has been a hidden population," Mattila said. "By looking for these events with infrared and radio telescopes, we may be able to discover many more, and learn from them."

Spitzer Space Telescope (SST).  Animation Credit: NASA

Such events may have been more common in the distant universe, so studying them may help scientists understand the environment in which galaxies developed billions of years ago.

The discovery, the scientists said, came as a surprise. The initial infrared burst was discovered as part of a project that sought to detect supernova explosions in such colliding pairs of galaxies. Arp 299 has seen numerous stellar explosions, and has been dubbed a "supernova factory." This new object originally was considered to be a supernova explosion. Only in 2011, six years after discovery, the radio-emitting portion began to show an elongation. Subsequent monitoring showed the expansion growing, confirming that what the scientists are seeing is a jet, not a supernova.

Hubble Space Telescope (HST). Animation Credits: NASA/ESA

Mattila and Perez-Torres led a team of 36 scientists from 26 institutions around the world in the observations of Arp 299. They published their findings in the June 14 issue of the journal Science.

The Long Baseline Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

For more information about NASA's Hubble Space Telescope, visit: https://www.nasa.gov/hubble

For more information about NASA's Spitzer Space Telescope, visit: https://www.nasa.gov/spitzer

Images (mentioned), Animations (mentioned), Text, Credits: NASA/JPL/Calla Cofield/NRAO/Dave Finley.

Greetings, Orbiter.ch

vendredi 15 juin 2018

A Refreshing Increase in Access to the Orbiting Lab

ISS - International Space Station logo.

June 15, 2018

A new, simple and cost-effective way to conduct experiments and test technology aboard the International Space Station offers another option to make space more accessible for out-of-this-world research. 

A partnership between the European Space Agency (ESA) and Space Application Services (SpaceAps) tests a new system for conducting research in space that lowers several barriers, including cost, development time and support. The International Commercial Experiment, or ICE Cubes Service, combines a sliding framework permanently installed in the space station’s Columbus module with “plug-and-play” Experiment Cubes. The easy to install and remove Experiment Cubes come in different sizes and often can be built with commercial off-the-shelf components, significantly reducing the cost and time to develop experiments. A ground model allows for integrated tests to verify all interface requirements and operational procedures.

Image above: Preparation of the experiment cubes for the International Commercial Experiment, or ICE Cubes Service. Image Credit: Space Applications Services.

“The idea is to provide fast, direct and affordable access to space for research, technology and education for any organization or customer,” says Hilde Stenuit of SpaceAps, which designed and developed the facility and made it flight-ready for recent delivery to the orbiting laboratory.

Following successful validation of the facility, the plan is to send the first batch of experiments using the system to the space station on an upcoming flight. These include a greenhouse used to observe plant growth rate and morphology under different lighting cycles in microgravity, an investigation of the effects of microgravity on bacteria in order to determine the feasibility of using the microorganisms to produce methane, and a kaleidoscope activated from the ground as a dynamic interactive art event.

SpaceAps, which has more than 30 years of experience developing and coordinating experiments for ESA research, provides service support to users of ICE Cubes. Researchers can monitor and control their orbiting Experiment Cubes in near real-time, from their own facilities, using the complimentary mission control software provided by SpaceAps.

Image above: The sliding framework permanently installed in the Columbus module for “plug-and-play” Experiment Cubes. Image Credit: Space Applications Services.

Ice Cubes Service plans to offer rides on launches approximately every four months, allowing experiments to run for shorter or longer time periods, an important feature for potential commercial users. Use of the system includes astronaut time and expert advice.

“There are many benefits of doing research without the influence of gravity,” Stenuit says. “Removing gravity unveils effects not previously observed or not observable on Earth, allowing research that cannot possibly be done in terrestrial laboratories.”

ICE Cubes reduces the preparation time for launch and offers users one point of contact and a simple, fixed pricing policy.

Image above: An Experiment Cube installed in the ICE Cubes Facility (ICF) in the Columbus European Physiology Module (EPM) rack. Image Credit: NASA.

The system supports both fundamental and applied research in a wide range of disciplines, from pharmaceutical development to experiments on stem cells, radiation, and microbiology, fluid sciences and more. It provides the opportunity to conduct testing and validation of space technologies and processes in a true space environment. Because ICE Cubes can accommodate free-floating experiments in the ESA Columbus module, it can even be used to test guidance, navigation and docking equipment. The system also can support education experiments and demonstrations to inspire future generations of scientists and explorers.

In short, ICE Cubes removes many barriers that limit access to space, providing more people access to flight opportunities.

An international partnership of the United States, Russia, Europe, Japan, and Canada, the space station facilitates growth of a robust commercial market in low-Earth orbit, operating as a microgravity laboratory for scientific research and technology demonstrations under conditions not available on Earth.

Related links:

ICE Cubes Service: http://www.icecubesservice.com/

European Space Agency (ESA): http://www.esa.int/ESA

Spot the Station: https://spotthestation.nasa.gov/

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Science Office/Melissa Gaskill.

Greetings, Orbiter.ch

Space Station Science Highlights: Week of June 11, 2018

ISS - Expedition 56 Mission patch.

Space Station Science Highlights: Week of June 11, 2018

June 15, 2018

Scientific work continued aboard the International Space Station this week, as crew members collected biological samples, observed crystal growth, tested grip force, and more.

International Space Station (ISS). Animation Credit: NASA

NASA astronaut Serena Auñón-Chancellor, Alexander Gerst of the European Space Agency (ESA), and Sergey Prokopyev of Roscosmos recently joined Expedition 56 and began pitching in on these and other science tasks.

Here are more details on this week’s scientific work aboard your orbiting laboratory:

Crystal close-ups

Advanced Colloids Experiment-Temperature-7 (ACE-T-7) investigates self-assembled colloids, which are complex three-dimensional structures made from small particles suspended within a fluid medium. These are vital to design of advanced optical materials and active devices.

Image above: NASA astronaut Ricky Arnold performs maintenance on the Advanced Colloids Experiment Module located inside the Light Microscopy Module, a modified commercial, highly flexible, state-of-the-art light imaging microscope facility that provides researchers with powerful diagnostic hardware and software in microgravity. Image Credit: NASA.

Activity on ACE-T-7 this week included mixing of Capillaries 1, 2 and 3 based on observed crystal formation. Science imaging of all three capillaries continues, as well as adjusting camera settings on Capillary 1 to optimize surface crystal images.

That feeling in your gut

Fecal samples were collected for JAXA’s Multi-Omics experiment and placed in the Minus Eighty-Degree Celsius Laboratory Freezer for ISS (MELFI). Crew also collected saliva samples for the investigation.

Multi-Omics evaluates how the space environment and prebiotics affect an astronauts’ immune function, combining data on changes in the gut microbial composition, metabolites profiles, and the immune system.

Get a grip

Image above: Astronaut Alexander Gerst of the European Space Agency conducts part of the GRIP investigation, which tests how spaceflight affects grip force and upper limb movements. Image Credit: NASA.

The European Space Agency’s GRIP investigation studies the effects of long-duration spaceflight and the forces of gravity and inertia on grip force and upper limb movements during manipulation of objects. Results may provide insight into potential hazards as astronauts move between different gravitational environments, as well as support design and control of human-computer interactions in challenging environments such as space. Information from the investigation also could be useful for rehabilitation of impaired upper limb control as a result of neurological diseases in patients on Earth.

This week, the crew completed the third of three GRIP operations in the supine position, or lying down facing up.

Blood, breath, and no tears

Image above: NASA astronaut Serena Auñón-Chancellor preparing to conduct air sampling for the Marrow investigation, a study of microgravity’s effect on bone marrow and the blood cells it produces. Image Credit: NASA.

Crew collected breath and blood samples for CSA’s Marrow investigation, which looks at the effect of microgravity on bone marrow. It is believed that microgravity has a negative effect on the bone marrow and the blood cells produced in bone marrow, similar to the effects of long-duration bed rest on Earth.

This week also included collection of blood samples for JAXA’s CFE and Medical Proteomics investigations, Vascular Echo, Functional Immune and Probiotics.

Space to Ground: Enhancing the View: 06/15/2018

Other work was done on these investigations: Atomization, Nanoracks/Barrios PCG, CEO, ASIM, Microbial Tracking 2, Plant Habitat, Area PADLES, Veggie/PONDS, HDEV, JEM Camera Robot, Vascular Echo, Functional Immune, Probiotics, and CAL.

Related links:

Advanced Colloids Experiment-Temperature-7 (ACE-T-7): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1708

JAXA’s Multi-Omics: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1689

Minus Eighty-Degree Celsius Laboratory Freezer for ISS (MELFI): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=56

European Space Agency’s GRIP: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1188

CSA’s Marrow: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1673

Vascular Echo: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1664

Functional Immune: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2011

Probiotics: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2047

Atomization: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=282

Nanoracks/Barrios PCG: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7726

CEO: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=84

ASIM: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1822

Microbial Tracking 2: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1663

Plant Habitat: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2032

Area PADLES: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=877

Veggie/PONDS: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7581

HDEV: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=892

JEM Camera Robot: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7516

CAL: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7396

Spot the Station: https://spotthestation.nasa.gov/

Expedition 56: https://www.nasa.gov/mission_pages/station/expeditions/expedition56/index.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Animation (mentioned), Images (mentioned), Video, Text, Credits: NASA/Michael Johnson/John Love, Lead Increment Scientist (Acting) Expeditions 55 & 56.

Best regards, Orbiter.ch

Record-Setting NASA Astronaut Peggy Whitson Retires

NASA logo.

June 15, 2018

NASA astronaut Peggy Whitson, who holds the U.S. record for most cumulative time in space, is retiring from the agency, effective Friday.

“Peggy Whitson is a testament to the American spirit,” said NASA Administrator Jim Bridenstine. “Her determination, strength of mind, character, and dedication to science, exploration, and discovery are an inspiration to NASA and America. We owe her a great debt for her service and she will be missed. We thank her for her service to our agency and country.”

Whitson, a native of Beaconsfield, Iowa, first came to NASA in 1986 as a National Research Council Resident Research Associate at NASA’s Johnson Space Center in Houston. She served in a number of scientific roles, including project scientist for the Shuttle-Mir Program and co-chair of the U.S.-Russian Mission Science Working Group, before her selection to the astronaut corps in 1996.

“It has been the utmost honor to have Peggy Whitson represent our entire NASA Flight Operations team,” said Brian Kelly, director of Flight Operations at Johnson. “She set the highest standards for human spaceflight operations, as well as being an outstanding role model for women and men in America and across the globe. Godspeed, Peg.”

As an astronaut, Whitson completed three long-duration missions to the International Space Station, setting records on each. She made her first trip in 2002 as part of Expedition 5, during which she took part in 21 science investigations and became NASA’s first space station science officer. In 2008, Whitson returned on Expedition 16 and became the first female commander of the space station.

During her most recent mission, spanning Expeditions 50, 51 and 52 from November 2016 to September 2017, Whitson became the first woman to command the space station twice (Expedition 51). She also claimed the title for most spacewalks by a woman – 10 spacewalks totaling 60 hours and 21 minutes – and set the record for most time spent in space by a U.S. astronaut at 665 days.

Whitson’s time on the ground at NASA was no less groundbreaking. She served as chief of the astronaut corps from 2009 to 2012, becoming both the first woman to hold the position and the first non-military astronaut corps chief.

“Peggy is a classmate and a friend, and she will be deeply missed,” said Pat Forrester, current chief of the Astronaut Office. “Along with her record setting career, she leaves behind a legacy of her passion for space.”

Find Whitson’s complete biography at: https://www.nasa.gov/astronauts/biographies/peggy-a-whitson

First female commander at ISS: https://www.nasa.gov/multimedia/imagegallery/image_feature_935.html

Image (mentioned), Text, Credits: NASA/Stephanie Schierholz/Sean Potter/JSC/Brandi Dean.

Greetings, Orbiter.ch

Bang and Whoosh!

NASA - Mars Reconnaissance Orbiter (MRO) patch.

June 15, 2018

This HiRISE image from NASA's Mars Reconnaissance Orbiter (MRO) captures a new, dated (within about a decade) impact crater that triggered a slope streak. When the meteoroid hit the surface and exploded to make the crater, it also destabilized the slope and initiated this avalanche.

The crater itself is only 5 meters across, but the streak it started is 1 kilometer long! Slope streaks are created when dry dust avalanches leave behind dark swaths on dusty Martian hills. The faded scar of an old avalanche is also visible to the side of the new dark streak.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Mars Reconnaissance Orbiter (MRO): http://www.nasa.gov/mission_pages/MRO/main/index.html

Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Univ. of Arizona.

Greetings, Orbiter.ch

Major work starts to boost the luminosity of the LHC

CERN - European Organization for Nuclear Research logo.

15 Jun 2018

Image above: Civil works have begun on the ATLAS and CMS sites to build new underground structures for the High-Luminosity LHC. (Image: Julien Ordan / CERN).

The Large Hadron Collider (LHC) is officially entering a new stage. Today, a ground-breaking ceremony at CERN celebrates the start of the civil-engineering work for the High-Luminosity LHC (HL-LHC): a new milestone in CERN’s history. By 2026 this major upgrade will have considerably improved the performance of the LHC, by increasing the number of collisions in the large experiments and thus boosting the probability of the discovery of new physics phenomena.

The LHC started colliding particles in 2010. Inside the 27-km LHC ring, bunches of protons travel at almost the speed of light and collide at four interaction points. These collisions generate new particles, which are measured by detectors surrounding the interaction points. By analysing these collisions, physicists from all over the world are deepening our understanding of the laws of nature.

While the LHC is able to produce up to 1 billion proton-proton collisions per second, the HL-LHC will increase this number, referred to by physicists as “luminosity”, by a factor of between five and seven, allowing about 10 times more data to be accumulated between 2026 and 2036. This means that physicists will be able to investigate rare phenomena and make more accurate measurements. For example, the LHC allowed physicists to unearth the Higgs boson in 2012, thereby making great progress in understanding how particles acquire their mass. The HL-LHC upgrade will allow the Higgs boson’s properties to be defined more accurately, and to measure with increased precision how it is produced, how it decays and how it interacts with other particles. In addition, scenarios beyond the Standard Model will be investigated, including supersymmetry (SUSY), theories about extra dimensions and quark substructure (compositeness).

“The High-Luminosity LHC will extend the LHC’s reach beyond its initial mission, bringing new opportunities for discovery, measuring the properties of particles such as the Higgs boson with greater precision, and exploring the fundamental constituents of the universe ever more profoundly,” said CERN Director-General Fabiola Gianotti.

The HL-LHC project started as an international endeavour involving 29 institutes from 13 countries. It began in November 2011 and two years later was identified as one of the main priorities of the European Strategy for Particle Physics, before the project was formally approved by the CERN Council in June 2016. After successful prototyping, many new hardware elements will be constructed and installed in the years to come. Overall, more than 1.2 km of the current machine will need to be replaced with many new high-technology components such as magnets, collimators and radiofrequency cavities. 

Image above: Prototype of a quadrupole magnet for the High-Luminosity LHC. (Image: Robert Hradil, Monika Majer/ProStudio22.ch).

The secret to increasing the collision rate is to squeeze the particle beam at the interaction points so that the probability of proton-proton collisions increases. To achieve this, the HL-LHC requires about 130 new magnets, in particular 24 new superconducting focusing quadrupoles to focus the beam and four superconducting dipoles. Both the quadrupoles and dipoles reach a field of about 11.5 tesla, as compared to the 8.3 tesla dipoles currently in use in the LHC. Sixteen brand-new “crab cavities” will also be installed to maximise the overlap of the proton bunches at the collision points. Their function is to tilt the bunches so that they appear to move sideways – just like a crab.

Another key ingredient in increasing the overall luminosity in the LHC is to enhance the machine’s availability and efficiency. For this, the HL-LHC project includes the relocation of some equipment to make it more accessible for maintenance. The power converters of the magnets will thus be moved into separate galleries, connected by new innovative superconducting cables capable of carrying up to 100 kA with almost zero energy dissipation.

“Audacity underpins the history of CERN and the High-Luminosity LHC writes a new chapter, building a bridge to the future,” said CERN’s Director for Accelerators and Technology, Frédérick Bordry. “It will allow new research and with its new innovative technologies, it is also a window to the accelerators of the future and to new applications for society.”

To allow all these improvements to be carried out, major civil-engineering work at two main sites is needed, in Switzerland and in France. This includes the construction of new buildings, shafts, caverns and underground galleries. Tunnels and underground halls will house new cryogenic equipment, the electrical power supply systems and various plants for electricity, cooling and ventilation.

The road to High Luminosity: what's next for the LHC?

Video above: The LHC will receive a major upgrade and transform into the High-Luminosity LHC over the coming years. But what does this mean and how will its goals be achieved? Find out in this video featuring several people involved in the project. (Video: Polar Media/CERN.).

During the civil engineering work, the LHC will continue to operate, with two long technical stop periods that will allow preparations and installations to be made for high luminosity alongside yearly regular maintenance activities. After completion of this major upgrade, the LHC is expected to produce data in high-luminosity mode from 2026 onwards. By pushing the frontiers of accelerator and detector technology, it will also pave the way for future higher-energy accelerators.


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): https://home.web.cern.ch/topics/large-hadron-collider

High-Luminosity LHC (HL-LHC): https://home.web.cern.ch/topics/high-luminosity-lhc

Supersymmetry (SUSY): https://home.web.cern.ch/about/physics/supersymmetry

Higgs boson: https://home.web.cern.ch/topics/higgs-boson

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Images (mentioned), Video (mentioned), Text, Credits: CERN/Corinne Pralavorio.

Best regards, Orbiter.ch

jeudi 14 juin 2018

NASA Encounters the Perfect Storm for Science

JPL - Jet Propulsion Laboratory logo.

June 13, 2018

Animation above: This set of images from NASA’s Mars Reconnaissance Orbiter shows a fierce dust storm is kicking up on Mars, with rovers on the surface indicated as icons. Animation Credits: NASA/JPL-Caltech/MSSS.

One of the thickest dust storms ever observed on Mars has been spreading for the past week and a half. The storm has caused NASA's Opportunity rover to suspend science operations, but also offers a window for four other spacecraft to learn from the swirling dust.

NASA has three orbiters circling the Red Planet, each equipped with special cameras and other atmospheric instruments. Additionally, NASA's Curiosity rover has begun to see an increase in dust at its location in Gale Crater.

"This is the ideal storm for Mars science," said Jim Watzin, director of NASA's Mars Exploration Program at the agency’s headquarters in Washington. "We have a historic number of spacecraft operating at the Red Planet. Each offers a unique look at how dust storms form and behave -- knowledge that will be essential for future robotic and human missions."

Dusty With a Chance of Dust

Dust storms are a frequent feature on Mars, occurring in all seasons. Occasionally, they can balloon into regional storms in a matter of days, and sometimes even expand until they envelop the planet. These massive, planet-scaled storms are estimated to happen about once every three to four Mars years (six to eight Earth years); the last one was in 2007. They can last weeks, or even months at the longest.

The current storm above Opportunity, which is still growing, now blankets 14 million square miles (35 million square kilometers) of Martian surface -- about a quarter of the planet.

Image above: These two views from NASA’s Curiosity rover, acquired specifically to measure the amount of dust inside Gale Crater, show that dust has increased over three days from a major Martian dust storm. The left-hand image shows a view of the east-northeast rim of Gale Crater on June 7, 2018 (Sol 2074); the right-hand image shows a view of the same feature on June 10, 2018 (Sol 2077). The images were taken by the rover’s Mastcam. Image Credits: NASA/JPL-Caltech/MSSS.

All dust events, regardless of size, help shape the Martian surface. Studying their physics is critical to understanding the ancient and modern Martian climate, said Rich Zurek, chief scientist for the Mars Program Office at NASA's Jet Propulsion Laboratory in Pasadena, California.

"Each observation of these large storms brings us closer to being able to model these events -- and maybe, someday, being able to forecast them," Zurek said. "That would be like forecasting El Niño events on Earth, or the severity of upcoming hurricane seasons."

The thin atmosphere makes these storms vastly different from anything encountered on Earth: Despite the drama of "The Martian," the most powerful surface winds encountered on Mars would not topple a spacecraft, although they can sand-blast dust particles into the atmosphere.


Members of NASA's spacecraft "family" at Mars often help each other out. The agency's orbiters regularly relay data from NASA's rovers back to Earth. Orbiters and rovers also offer different perspectives on Martian terrain, allowing their science to complement one another.

The Mars Reconnaissance Orbiter has a special role, acting as an early warning system for weather events such as the recent storm. It was the orbiter's wide-angle camera, called the Mars Color Imager, that offered the Opportunity team a heads up about the storm. This imager, built and operated by Malin Space Science Systems in San Diego, can create daily global maps of the planet that track how storms evolve, not unlike weather satellites that track hurricanes here on Earth.

Image above: This series of images shows simulated views of a darkening Martian sky blotting out the Sun from NASA’s Opportunity rover’s point of view, with the right side simulating Opportunity’s current view in the global dust storm (June 2018). Image Credits: NASA/JPL-Caltech/TAMU.

NASA's two other orbiters -- 2001 Mars Odyssey and MAVEN (Mars Atmosphere and Volatile Evolution) -- also provide unique science views. Odyssey has an infrared camera called THEMIS (Thermal Emission Imaging System) that can measure the amount of dust below it; MAVEN is designed to study the behavior of the upper atmosphere and the loss of gas to space.

Science happens on the ground as well, of course. Despite being on the other side of the planet from the evolving dust storm, NASA's Curiosity rover is beginning to detect increased "tau," the measure of the veil of dusty haze that blots out sunlight during a storm. As of Tuesday, June 12, the tau inside Gale Crater was varying between 1.0 and 2.0 -- figures that are average for dust season, though these levels usually show up later in the season.

Fortunately, Curiosity has a nuclear-powered battery. That means it doesn't face the same risk as the solar-powered Opportunity.

The Next Big One?

Since 2007, Mars scientists have been patiently waiting for a planet-encircling dust event -- less precisely called a "global" dust storm, though the storms never truly cover the entire globe of Mars. In 1971, one of these storms came close, leaving just the peaks of Mars' Tharsis volcanoes poking out above the dust.

Image above: This graphic shows the ongoing contributions of NASA’s rovers and orbiters during a Martian dust storm that began on May 30, 2018. Image Credits: NASA/JPL-Caltech.

The most recent dust storm is the earliest ever observed in the northern hemisphere of Mars, said Bruce Cantor of Malin Space Science Systems, deputy principal investigator for the Mars Color Imager. But it could take several more days before anyone can tell whether the storm is encircling the planet.

If it does "go global," the storm will offer a brand new look at Martian weather. Four spacecraft stand ready to collect the science that shakes out.

Fine Print

JPL, a division of Caltech in Pasadena, California, manages the Mars Exploration Rover mission; the Mars Science Laboratory/Curiosity rover; the Mars Reconnaissance Orbiter Project; and the 2001 Mars Odyssey orbiter for NASA's Science Mission Directorate, Washington.

Image above: This graphic shows how the energy available to NASA’s Opportunity rover on Mars (in watt-hours) depends on how clear or opaque the atmosphere is (measured in a value called tau). When the tau value (blue) is high, the rover’s power levels (yellow) drop. Image Credits: NASA/JPL-Caltech/New Mexico Museum of Natural History.

NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN project for NASA's Science Mission Directorate, Washington. MAVEN's principal investigator is based at the University of Colorado Boulder's Laboratory for Atmospheric and Space Physics.

Lockheed Martin Space Systems, Denver, is the prime contractor for the Odyssey, MRO and MAVEN projects, having developed and built all three orbiters. Mission operations are conducted jointly from Lockheed Martin and from JPL for Odyssey and MRO, and jointly with the GSFC for MAVEN.

The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Philip Christensen at Arizona State University.

Related articles:

Shades of Martian Darkness

Opportunity Hunkers Down During Dust Storm

For more updates about the Martian dust storm visit: https://mars.nasa.gov/weather

For more information about NASA's Mars missions, visit: https://mars.nasa.gov/

Jet Propulsion Laboratory (JPL): https://www.nasa.gov/centers/jpl/home/index.html

Animation (mentioned), Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Andrew Good.

Greetings, Orbiter.ch