vendredi 29 août 2014

Memory Reformat Planned for Opportunity Mars Rover










NASA - Mars Science Laboratory (MSL) logo.

August 29, 2014

An increasing frequency of computer resets on NASA's Mars Exploration Rover Opportunity has prompted the rover team to make plans to reformat the rover's flash memory.

The resets, including a dozen this month, interfere with the rover's planned science activities, even though recovery from each incident is completed within a day or two.

Flash memory retains data even when power is off. It is the type used for storing photos and songs on smart phones or digital cameras, among many other uses. Individual cells within a flash memory sector can wear out from repeated use. Reformatting clears the memory while identifying bad cells and flagging them to be avoided.


Image above: NASA's Mars rover Opportunity captured this view southward just after completing a 338-foot (103-meter) southward drive, in reverse, on Aug. 10, 2014. The foreground of this view from the rover's Navcam includes the rear portion of the rover's deck. The ground beyond bears wind-blown lines of sand. Image Credit: NASA/JPL-Caltech.

"Worn-out cells in the flash memory are the leading suspect in causing these resets," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, California, project manager for NASA's Mars Exploration Rover Project. "The flash reformatting is a low-risk process, as critical sequences and flight software are stored elsewhere in other non-volatile memory on the rover."

The project landed twin rovers Spirit and Opportunity on Mars in early 2004 to begin missions planned to last only three months. Spirit worked for six years, and Opportunity is still active. Findings about ancient wet environments on Mars have come from both rovers.

The project reformatted the flash memory on Spirit five years ago to stop a series of amnesia events Spirit had been experiencing. The reformatting planned for early next month will be the first for Opportunity. Even after the rover has been active for more than a decade and is currently about 125 million miles (about 200 million kilometers) from JPL, the rover team can still perform this type of upkeep.

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

Preparations include downloading to Earth all useful data remaining in the flash memory and switching the rover to an operating mode that does not use flash memory. Also, the team is restructuring the rover's communication sessions to use a slower data rate, which may add resilience in case of a reset during these preparations.

The Mars Exploration Rover Project is one element of NASA's ongoing and future Mars missions preparing for a human mission to the planet in the 2030s. JPL, a division of the California Institute of Technology, manages the project for NASA's Science Mission Directorate in Washington.

For more information about NASA’s Mars rovers Spirit and Opportunity, visit these sites: http://www.nasa.gov/rovers and http://marsrovers.jpl.nasa.gov

Follow the project on Twitter at: http://twitter.com/MarsRovers

On Facebook, visit: http://www.facebook.com/mars.rovers

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

Best regards, Orbiter.ch

NASA Probes Studying Earth’s Radiation Belts to Celebrate Two Year Anniversary










NASA - Van Allen Probes logo.

August 29, 2014

NASA's twin Van Allen Probes will celebrate on Saturday two years of studying the sun’s influence on our planet and near-Earth space. The probes, shortly after launch in August 2012, discovered a third radiation belt around Earth when only two had previously been detected.

The radiation belts are layers of energetic charged particles held in place by the magnetic field surrounding our planet. The new third belt occurred only occasionally but persisted for as long as a month. This revealed to scientists the dynamic and variable nature of the radiation belts and provided new insight into how they respond to solar activity.


Image above: This image was created using data from the Relativistic Electron-Proton Telescopes on NASA's twin Van Allen Probes. It shows the emergence of a new third transient radiation belt. The new belt is seen as the middle orange and red arc of the three seen on each side of the Earth. Image Credit: APL, NASA.

"The primary science objective of the Van Allen Probes is to provide understanding of how particles in the radiation belts form and change in response to energy input from the sun," said Mona Kessel, the mission’s program scientist at NASA Headquarters in Washington.  "The discoveries and understanding gained have far exceeded expectations."

The probes, each weighing just less than 1,500 pounds, were specifically designed to withstand and study the harsh radiation belt region around Earth. The belts are critical regions that have a connection to Earth’s atmosphere and space-based technologies. The belts are affected by solar storms and space weather events and as a result, can swell dramatically. When this occurs, they can pose dangers to communications and GPS satellites, as well as humans in low-Earth orbit.

Formerly known as the Radiation Belt Storm Probes, the mission was renamed Van Allen Probes in November 2012 in honor of Dr. James Van Allen, who discovered the two radiation belts in 1958.

The twin spacecraft have also revealed how particles in the heart of the belts can be accelerated to nearly the speed of light; proven that electrons in the belts are undergoing acceleration from very low frequency plasma waves; and shown persistent stripe-like structures are a common feature of the inner belt, and are caused by Earth’s rotation, a mechanism previously thought to be incapable of such an effect.

Van Allen Probes

“The Van Allen Probes mission has given us the means to validate theories about plasma physics and the acceleration processes going on inside the belts,” said Barry Mauk, Van Allen Probes project scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. “They also have shown us new structures and features in this region of space, the existence of which we had never suspected. It has been a very illuminating two years, and we look forward to many more with these remarkable spacecraft.”

The Van Allen Probes are the second mission in NASA's Living With a Star (LWS) Program to explore aspects of the connected sun-Earth system that directly affect life and society. LWS is managed by the agency's Goddard Space Flight Center in Greenbelt, Maryland. APL built the spacecraft and manages the mission for the agency’s Science Mission Directorate in Washington.

For more information about NASA’s Van Allen Probes, visit: http://www.nasa.gov/vanallenprobes

Images, Text, Credits: NASA / Dwayne Brown / Johns Hopkins University Applied Physics Laboratory / Geoff Brown.

Greetings, Orbiter.ch

Hubble Looks at Light and Dark in the Universe











NASA - Hubble Space Telescope patch.

Aug. 29, 2014


This new NASA/ESA Hubble Space Telescope image shows a variety of intriguing cosmic phenomena.

Surrounded by bright stars, towards the upper middle of the frame we see a small young stellar object (YSO) known as SSTC2D J033038.2+303212. Located in the constellation of Perseus, this star is in the early stages of its life and is still forming into a fully-grown star. In this view from Hubble’s Advanced Camera for Surveys(ACS) it appears to have a murky chimney of material emanating outwards and downwards, framed by bright bursts of gas flowing from the star itself. This fledgling star is actually surrounded by a bright disk of material swirling around it as it forms — a disc that we see edge-on from our perspective.

However, this small bright speck is dwarfed by its cosmic neighbor towards the bottom of the frame, a clump of bright, wispy gas swirling around as it appears to spew dark material out into space. The bright cloud is a reflection nebula known as [B77] 63, a cloud of interstellar gas that is reflecting light from the stars embedded within it. There are actually a number of bright stars within [B77] 63, most notably the emission-line star LkHA 326, and it nearby neighbor LZK 18.

These stars are lighting up the surrounding gas and sculpting it into the wispy shape seen in this image. However, the most dramatic part of the image seems to be a dark stream of smoke piling outwards from [B77] 63 and its stars — a dark nebula called Dobashi 4173. Dark nebulae are incredibly dense clouds of pitch-dark material that obscure the patches of sky behind them, seemingly creating great rips and eerily empty chunks of sky. The stars speckled on top of this extreme blackness actually lie between us and Dobashi 4173.

video
 Hubble orbiting Earth

The Hubble Space Telescope is a project of international cooperation between NASA and the 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 images and more information about Hubble, visit: http://www.nasa.gov/hubble and http://www.spacetelescope.org/

Image, Video, Text, Credits: ESA/NASA.

Cheers, Orbiter.ch

jeudi 28 août 2014

NASA Sees Massive Hurricane Marie












NASA / NOAA - GOES Mission logo.

August 28, 2014

Marie (Eastern Pacific)

When NOAA's GOES-West satellite captured an image of what is now Tropical Storm Marie, weakened from hurricane status on August 28, the strongest thunderstorms were located in the southern quadrant of the storm.

NOAA's GOES-West satellite captured an image of Marie on August 28 at 11 a.m. EDT. Bands of thunderstorms circled the storm especially to the north. The National Hurricane Center noted that Marie has continued to produce a small area of convection (rising air that forms the thunderstorms that make up Marie) south and east of the center during some hours on the morning of August 28. The GOES image was created by the NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Infrared data, such as that from the Atmospheric Infrared Sounder instrument aboard NASA's Aqua satellite showed that cloud tops had warmed. Warming cloud tops means that the strength in the uplift of air (that pushes cloud tops higher into the colder levels of the atmosphere) has weakened, and clouds are not getting as high as they did before. The higher the thunderstorms, the stronger they usually are, but Marie's are dropping in height.


Image above: This image of Tropical Storm Marie was captured by NOAA's GOES-West satellite on August 28 at 11 a.m. EDT and showed the strongest storms were south of the center. Image Credit: NASA/NOAA GOES Project.

Marie is not able to generate strong thunderstorms because it has moved over cooler waters. Sea surface temperatures of at least 80 F (26.6 C) are needed to maintain a hurricane's strength. Marie is in waters as cool as 22C (71.6F).

At 11 a.m. EDT (1500 UTC) Marie's maximum sustained winds were down to 45 mph (75 kph) and weakening. Marie was centered near latitude 25.4 north and longitude 128.9 west, about 865 miles (1,395 km) west of Punta Eugenia, Mexico. Marie is moving northwest at 15 mph (24 kph).

The NHC expects Marie should become post-tropical by tonight, August 28. Meanwhile Marie continues kicking up rough surf. Large southerly swells affecting much of the west coast of the Baja California peninsula and the coast of southern California will gradually subside through Friday, August 29. These swells could still produce life-threatening surf and rip currents, as well as minor coastal flooding around the time of high tide.

For following the evolution of the Tropical Storm Marie, visit: http://www.nasa.gov/content/goddard/marie-eastern-pacific/index.html

Image (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro.

Greetings, Orbiter.ch

Researchers Use NASA and Other Data to Look Into the Heart of a Solar Storm












NASA / ESA - SOHO Mission patch.

August 28, 2014


Animation above: A coronal mass ejection on Jan. 20, 2005, produced an extreme amount of solar particles, seen as white static in this imagery from ESA/NASA's Solar and Heliospheric Observatory. Closer to Earth, it created a solar storm with an unusual combination of strong and weak effects. Image Credit: ESA/NASA/SOHO.

A space weather storm from the sun engulfed our planet on Jan. 21, 2005. The event got its start on Jan. 20, when a cloud of solar material, a coronal mass ejection or CME, burst off the sun and headed toward Earth. When it arrived at our planet, the ring current and radiation belts surrounding Earth swelled with extra particles, while the aurora persisted for six hours. Both of these are usually signs of a very large storm – indeed, this was one of the largest outpouring of solar protons ever monitored from the sun. But the storm barely affected the magnetic fields around Earth – disturbances in these fields can affect power grids on the ground, a potential space weather effect keenly watched for by a society so dependent on electricity.

Janet Kozyra, a space scientist at the University of Michigan in Ann Arbor, thought this intriguing combination of a simultaneously weak and strong solar storm deserved further scrutiny. In an effort to better understand -- and some day forecast -- such storms and their potential effects on human technology, an unusual event like this can help researchers understand just what aspects of a CME lead to what effects near Earth.

"There were features appearing that we generally only see during extreme space weather events, when by other measures the storm was moderate," said Kozyra. "We wanted to look at it holistically, much like terrestrial weather researchers do with extreme weather. We took every single piece of data that we could find on the solar storm and put it together to see what was going on."


Image above: Caption: A filament of cold dense solar material moved toward the front of a Jan. 20, 2005, coronal mass ejection, which led to an unusually large amount of solar material funneling into near-Earth space during a Jan. 21 solar storm. Image Credit: Janet Kozyra.

With observations collected from ground-based networks and 20 different satellites, Kozyra and a group of colleagues, each an expert in different aspects of the data or models, found that the CME contained a rare piece of dense solar filament material. This filament coupled with an unusually fast speed led to the large amount of solar material observed. A fortuitous magnetic geometry, however, softened the blow, leading to reduced magnetic effects. These results were published in the Aug. 14, 2014, issue of Journal of Geophysical Research, Space Physics.

The researchers gathered data from spacecraft orbiting in Earth's ionosphere, which extends up to 600 miles above the planet’s surface, and satellites above that, orbiting through the heart of Earth's magnetic environment, the magnetosphere. The massive amount of data was then incorporated into a variety of models developed at the University of Michigan’s Center for Space Environment Modeling, which are housed at the Community Coordinated Modeling Center at NASA's Goddard Space Flight Center in Greenbelt, Maryland, a facility dedicated to providing comprehensive access to space weather models.

With the models in hand, the team could put together the story of this particular solar storm. It began with the CME on Jan. 20, 2005. The European Space Agency and NASA's Solar and Heliospheric Observatory, or SOHO, captured images of the CME. At their simplest, CMEs look like a magnetic bubble with material around the outside. In this case, there was an additional line of colder, denser solar material – an electrically charged gas called plasma – inside called a solar filament. Solar filaments are ribbons of dense plasma supported in the sun’s outer atmosphere – the corona -- by strong magnetic fields. Filament material is 100 times denser and 100 times cooler than the surrounding atmosphere. When the supporting magnetic fields erupt, the filaments are caught up in the explosive release that forms the CME. Despite observations that the majority of eruptions like this involve solar filaments, the filaments are rarely identified in disturbances that reach Earth. Why this might be, is a mystery – but it means that the presence of the solar filament in this particular event is a rare sighting.


Image above: Twelve spacecraft in Earth’s magnetosphere – in addition to other missions -- helped scientists better observe and understand an unusual January 2005 solar storm. The four Cluster spacecraft were in the solar wind, directly upstream of Earth. Picture not to scale. Image Credit: ESA.

Subsequent observations of the CME showed it to be particularly fast, with a velocity that peaked at around 1800 miles per second before slowing to 600 miles per second as it approached Earth. Just how many CMEs have filaments or how the geometry of such filaments change as they move toward Earth is not precisely known. In this case, however, it seems that the dense filament sped forward, past the leading edge of the CME, so as it slammed into the magnetosphere, it delivered an extra big dose of energetic particles into near-Earth space.

What happened next was observed by a flotilla of Earth-orbiting scientific satellites, including NASA's IMAGE, FAST and TIMED missions, the joint European Space Agency, or ESA, and NASA's Cluster, the NASA and ESA's Geotail, the Chinese and ESA's Double Star-1; other spacecraft 1 million miles closer to the sun including SOHO and NASA's Advanced Composition Explorer, Wind various other spacecraft; as well as the National Science Foundation-supported ground-based SuperDARN radar network. At the time Cluster was in the solar wind directly upstream of Earth. Meanwhile, Double Star-1 was passing from the outer region of the planet’s magnetic field and entering the magnetosphere. This enabled it to observe the entry of the solar filament material as it crossed into near-Earth space.

“Within one hour of the impact, a cold, dense plasma sheet formed out of the filament material," said Kozyra. "High density material continued to move through the magnetosphere for the entire six hours of the filament’s passage."

Despite the intense amount of plasma carried by the CME, it still lacked a key component of a super storm. The magnetic fields embedded in this CME generally pointed toward Earth's north pole, just as Earth's own magnetic fields do. This configuration causes far fewer disruptions to our planet's system than when the CME's fields point southward. When pointing south, the CME's fields clash with Earth's, peeling them back and setting off magnetic perturbations that cascade through the magnetosphere.

The magnetic field orientation is what kept this solar storm to low levels. On the other hand, the extra solar material from the filament catalyzed long-term aurora over the poles and enhanced the particle filled radiation belts around Earth, characteristic of a larger storm.

"This event, with its unusual combination of space weather effects really demonstrates why it's important to look at the entire system, not just individual elements," said Kozyra. "Only by using all of this data, by watching the event from the beginning to the end, can we begin to understand all the different facets of an extreme storm like this."

Understanding what created the facets of this particular 2005 storm adds to a much larger body of knowledge about how different kinds of CMEs can affect us here at Earth. By knowing what factors lead to the total strength of a storm, we can better learn to predict what the sun is sending our way.

This work was supported by NASA’s Heliophysics Division, in combination with the National Science Foundation’s Division of Atmospheric and Geospace Sciences: http://www.nsf.gov/div/index.jsp?org=AGS

For more information about SOHO Mission, visit: http://soho.esac.esa.int/ and http://www.nasa.gov/mission_pages/soho/

For more information about Cluster Mission, visit: http://www.esa.int/Our_Activities/Space_Science/Cluster_overview2

Images and Animation (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Karen C. Fox.

Best regards, Orbiter.ch

NASA's Spitzer Telescope Witnesses Asteroid Smashup












NASA - Spitzer Space Telescope patch.

August 28, 2014

NASA's Spitzer Space Telescope has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the formation of planets.

Scientists had been regularly tracking the star, called NGC 2547-ID8, when it surged with a huge amount of fresh dust between August 2012 and January 2013.

"We think two big asteroids crashed into each other, creating a huge cloud of grains the size of very fine sand, which are now smashing themselves into smithereens and slowly leaking away from the star," said lead author and graduate student Huan Meng of the University of Arizona, Tucson.


Image above: This artist’s concept shows the immediate aftermath of a large asteroid impact around NGC 2547-ID8, a 35-million-year-old sun-like star. NASA's Spitzer Space Telescope witnessed a giant surge in dust around the star, likely the result of two asteroids colliding. Image Credit: NASA/JPL-Caltech.

While dusty aftermaths of suspected asteroid collisions have been observed by Spitzer before, this is the first time scientists have collected data before and after a planetary system smashup. The viewing offers a glimpse into the violent process of making rocky planets like ours.

Rocky planets begin life as dusty material circling around young stars. The material clumps together to form asteroids that ram into each other. Although the asteroids often are destroyed, some grow over time and transform into proto-planets. After about 100 million years, the objects mature into full-grown, terrestrial planets. Our moon is thought to have formed from a giant impact between proto-Earth and a Mars-size object.

In the new study, Spitzer set its heat-seeking infrared eyes on the dusty star NGC 2547-ID8, which is about 35 million years old and lies 1,200 light-years away in the Vela constellation. Previous observations had already recorded variations in the amount of dust around the star, hinting at possible ongoing asteroid collisions. In hope of witnessing an even larger impact, which is a key step in the birth of a terrestrial planet, the astronomers turned to Spitzer to observe the star regularly. Beginning in May 2012, the telescope began watching the star, sometimes daily.

A dramatic change in the star came during a time when Spitzer had to point away from NGC 2547-ID8 because our sun was in the way. When Spitzer started observing the star again five months later, the team was shocked by the data they received.

"We not only witnessed what appears to be the wreckage of a huge smashup, but have been able to track how it is changing -- the signal is fading as the cloud destroys itself by grinding its grains down so they escape from the star," said Kate Su of the University of Arizona and co-author on the study. "Spitzer is the best telescope for monitoring stars regularly and precisely for small changes in infrared light over months and even years."


Image above: Astronomers were surprised to see these data from NASA's Spitzer Space Telescope in January 2013, showing a huge eruption of dust around a star called NGC 2547-ID8. In this plot, infrared brightness is represented on the vertical axis, and time on the horizontal axis. Image Credit: NASA/JPL-Caltech/University of Arizona.

A very thick cloud of dusty debris now orbits the star in the zone where rocky planets form. As the scientists observe the star system, the infrared signal from this cloud varies based on what is visible from Earth. For example, when the elongated cloud is facing us, more of its surface area is exposed and the signal is greater. When the head or the tail of the cloud is in view, less infrared light is observed. By studying the infrared oscillations, the team is gathering first-of-its-kind data on the detailed process and outcome of collisions that create rocky planets like Earth.

"We are watching rocky planet formation happen right in front of us," said George Rieke, a University of Arizona co-author of the new study. "This is a unique chance to study this process in near real-time."

The team is continuing to keep an eye on the star with Spitzer. They will see how long the elevated dust levels persist, which will help them calculate how often such events happen around this and other stars, and they might see another smashup while Spitzer looks on.

Spitzer Space Telescope. Image Credits: NASA/JPL

The results of this study are posted online Thursday in the journal Science.

NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company in Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

For more information about Spitzer, visit: http://www.nasa.gov/spitzer

Images (mentioned), Text, Credits: NASA / Felicia Chou / JPL / Whitney Clavin.

Greetings, Orbiter.ch

mercredi 27 août 2014

Robonaut Gets New Legs as Trio Prepares for Homecoming












ISS - Expedition 40 Mission patch.

August 27, 2014

Expedition 40 participated in health checks, Robonaut upgrades and Soyuz emergency drills Wednesday. The International Space Station also boosted its orbit setting the stage for a crew departure and arrival in September.

Commander Steve Swanson joined Flight Engineer Reid Wiseman and Alexander Gerst for health checks during the morning. The trio checked each other’s blood pressure and temperature as part of their clinical exams.

Swanson then moved on to more Robonaut mobility upgrade activities throughout the day. The commander reviewed his upgrade tasks and set up cameras so ground controllers could view his installation work on the humanoid robot.


Image above: Commander Steve Swanson works with Robonaut 2 in the Destiny lab module. Image Credit: NASA TV.

Robonaut 2 is receiving new legs that will enable it to move inside and outside the space station. More upper body upgrades are scheduled for the end of 2014 before Robonaut will be ready to conduct its first spacewalk. Robonaut was designed to enhance crew productivity and safety while also aiding people on Earth with physical disabilities.

Read more about Robonaut 2: http://www.nasa.gov/robonaut

video
Space Station Live: Robonaut Mobility Upgrades

Wiseman and Swanson got together in the afternoon for a call with students from Elliot Ranch Elementary School in Elk Grove, Calif. The NASA astronaut duo answered basic questions about living and working in space.

Before the student call Wiseman joined his Soyuz crewmates cosmonaut Max Suraev and German astronaut Alexander Gerst for an emergency drill. They practiced their responsibilities in the unlikely event of an emergency such as a pressure leak which would require the crew to undock from the station and return home in its Soyuz lifeboat.

Gerst, a European Space Agency astronaut, spent a few minutes after his health exam on the VIABLE microbiology experiment. He was inside the Zarya cargo module checking experimental materials in a locker panel. The study seeks to maintain crew member health and prevent damage and contamination to space station hardware.

Read more about VIABLE: http://www.nasa.gov/mission_pages/station/research/experiments/806.html

Gerst then moved on to LAN cable maintenance in the Columbus lab module. After that work, he went inside the cupola and photographed its windows with the shutters closed to determine if any hardware might interfere with upcoming IMAX work.


Image above: One of the Expedition 40 crew members aboard the International Space Station recorded this colorful image of Aurora Australis on July 15, 2014. Image Credit: NASA.

Returning cosmonauts Alexander Skvortsov and Oleg Artemyev called down to specialists Wednesday morning to discuss search and rescue operations when they land in Kazakhstan. The duo, who conducted Soyuz departure preparations throughout the morning, will be joined by Swanson when they leave the station and undock from the Poisk docking compartment in their Soyuz TMA-12M spacecraft Sept. 10 ending Expedition 40.

Europe’s “Georges Lemaître” Automated Transfer Vehicle (ATV-5) fired its engines early in the morning slightly raising the station’s orbit while docked to the Zvezda service module. The reboost readies the Soyuz carrying the Expedition 40 trio home in two weeks. The orbital laboratory will also be in the proper phasing for the arrival of the Expedition 41 trio in its Soyuz TMA-14M spacecraft on Sept. 25.

The new Expedition 41 trio is composed of two veteran space-flyers, NASA astronaut Barry Wilmore, Soyuz Commander Alexander Samoukutyaev and new cosmonaut Elena Serova. They will take a near six-hour, or four-orbit, ride to the space station’s Poisk module. They are scheduled to return to Earth March 2015.

For more information about the International Space Station (ISS), visit: http://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Video, Text, Credits: NASA / NASA TV.

Cheers, Orbiter.ch

NASA Completes Key Review of World’s Most Powerful Rocket in Support of Journey to Mars











NASA logo.

August 27, 2014

NASA officials Wednesday announced they have completed a rigorous review of the Space Launch System (SLS) -- the heavy-lift, exploration class rocket under development to take humans beyond Earth orbit and to Mars -- and approved the program's progression from formulation to development, something no other exploration class vehicle has achieved since the agency built the space shuttle.

"We are on a journey of scientific and human exploration that leads to Mars," said NASA Administrator Charles Bolden. "And we’re firmly committed to building the launch vehicle and other supporting systems that will take us on that journey."

For its first flight test, SLS will be configured for a 70-metric-ton (77-ton) lift capacity and carry an uncrewed Orion spacecraft beyond low-Earth orbit. In its most powerful configuration, SLS will provide an unprecedented lift capability of 130 metric tons (143 tons), which will enable missions even farther into our solar system, including such destinations as an asteroid and Mars.


Image above: Artist concept of NASA’s Space Launch System (SLS) 70-metric-ton configuration launching to space. SLS will be the most powerful rocket ever built for deep space missions, including to an asteroid and ultimately to Mars. Image Credit: NASA/MSFC.

This decision comes after a thorough review known as Key Decision Point C (KDP-C), which provides a development cost baseline for the 70-metric ton version of the SLS of $7.021 billion from February 2014 through the first launch and a launch readiness schedule based on an initial SLS flight no later than November 2018.

Conservative cost and schedule commitments outlined in the KDP-C align the SLS program with program management best practices that account for potential technical risks and budgetary uncertainty beyond the program's control.

“Our nation is embarked on an ambitious space exploration program, and we owe it to the American taxpayers to get it right,” said Associate Administrator Robert Lightfoot, who oversaw the review process. “After rigorous review, we’re committing today to a funding level and readiness date that will keep us on track to sending humans to Mars in the 2030s – and we’re going to stand behind that commitment.”

"The Space Launch System Program has done exemplary work during the past three years to get us to this point," said William Gerstenmaier, associate administrator for the Human Explorations and Operations Mission Directorate at NASA Headquarters in Washington. "We will keep the teams working toward a more ambitious readiness date, but will be ready no later than November 2018.”

video
 Animation: NASA's Space Launch System (SLS)

The SLS, Orion, and Ground Systems Development and Operations programs each conduct a design review prior to each program’s respective KDP-C, and each program will establish cost and schedule commitments that account for its individual technical requirements.

"We are keeping each part of the program -- the rocket, ground systems, and Orion -- moving at its best possible speed toward the first integrated test launch,” said Bill Hill, director Exploration Systems Development at NASA. "We are on a solid path toward an integrated mission and making progress in all three programs every day."

“Engineers have made significant technical progress on the rocket and have produced hardware for all elements of the SLS program,” said SLS program manager Todd May. “The team members deserve an enormous amount of credit for their dedication to building this national asset.”

The program delivered in April the first piece of flight hardware for Orion’s maiden flight, Exploration Flight Test-1 targeted for December. This stage adapter is of the same design that will be used on SLS’s first flight, Exploration Mission-1.


Image above: This artist concept shows NASA’s Space Launch System, or SLS, rolling to a launchpad at Kennedy Space Center at night. SLS will be the most powerful rocket in history, and the flexible, evolvable design of this advanced, heavy-lift launch vehicle will meet a variety of crew and cargo mission needs. Image Credit: NASA/MSFC.

Michoud Assembly Facility in New Orleans has all major tools installed and is producing hardware, including the first pieces of flight hardware for SLS. Sixteen RS-25 engines, enough for four flights, currently are in inventory at Stennis Space Center, in Bay St. Louis, Mississippi, where an engine is already installed and ready for testing this fall. NASA contractor ATK has conducted successful test firings of the five-segment solid rocket boosters and is preparing for the first qualification motor test.

SLS will be the world's most capable rocket. In addition to opening new frontiers for explorers traveling aboard the Orion capsule, the SLS may also offer benefits for science missions that require its use and can’t be flown on commercial rockets.

The next phase of development for SLS is the Critical Design Review, a programmatic gate that reaffirms the agency's confidence in the program planning and technical risk posture.

Editor's Note:

For those who know me well, you know that I express my opinion, because I am fortunate to live in the only direct democracy in the world (the people are constitutionally sovereign) Switzerland, the American space program in the Obama era leaves me skeptical, because it reminds me Tango (the dance, three steps forward, two steps back.) I really hope that the mission to Mars have held in my lifetime.

For more information about SLS, visit: http://www.nasa.gov/sls

Images, Animation, Text, Credits: NASA / Stephanie Schierholz / Orbiter.ch Aerospace.

Best regards, Orbiter.ch

Witnessing the early growth of a giant












ESA - Hubble Space Telescope patch.

27 August 2014

First ever sighting of galaxy core formation

A Cauldron of Star Birth in the Center of a Young Galaxy

Astronomers have uncovered for the first time the earliest stages of a massive galaxy forming in the young Universe. The discovery was made possible through combining observations from the NASA/ESA Hubble Space Telescope, NASA's Spitzer Space Telescope, ESA's Herschel Space Observatory, and the W.M. Keck Observatory in Hawaii. The growing galaxy core is blazing with the light of millions of newborn stars that are forming at a ferocious rate. The paper appears in the journal Nature on 27 August.

Elliptical galaxies are large, gas-poor gatherings of older stars and are one of the main types of galaxy along with their spiral and lenticular relatives. Galaxy formation theories suggest that giant elliptical galaxies form from the inside out, with a large core marking the very first stages of formation.

However, evidence of this early construction phase has eluded astronomers — until now.

Distant galaxy core in the Hubble GOODS North field

Astronomers have now spotted a compact galactic core known as GOODS-N-774, and nicknamed Sparky [1]. It is seen as it appeared eleven billion years ago, just three billion years after the Big Bang.

"This core formation process is a phenomenon unique to the early Universe," explains Erica Nelson of Yale University, USA, lead author of the science paper announcing the results, "we do not see galaxies forming in this way any more. There's something about the Universe at that time that could form galaxies in this way that it now can't. We suspect that the Universe could produce denser objects because the Universe as a whole was denser shortly after the Big Bang. It is much less dense now, so it can't do it anymore."

Section of Hubble GOODS North field

Although only a fraction of the size of the Milky Way, the infant galaxy is crammed with so many young stars that it already contains twice as much mass as our entire galaxy. It is thought that the fledgling galaxy will continue to grow, eventually becoming a giant elliptical galaxy. The astronomers think that this barely visible galaxy may be representative of a much larger population of similar objects that are too faint or obscured by dust to be spotted — just like the Sun can appear red and faint behind the smoke of a forest fire.

Alongside determining the galaxy's size from the Hubble images, the team dug into archival far-infrared images from NASA's Spitzer Space Telescope and the ESA Herschel Space Observatory to see how fast the compact galaxy is churning out stars. GOODS-N-774 is producing 300 stars per year. "By comparison, the Milky Way produces thirty times fewer than this — roughly ten stars per year," [2] says Marijn Franx of Leiden University in the Netherlands, a co-author of the study. "This star-forming rate is really intense!"

Inset view of distant galaxy GOODS-N-774

This tiny powerhouse contains about twice as many stars as our galaxy, all crammed into a region only 6000 light-years across. The Milky Way is about 100 000 light-years across.

Astronomers believe that this frenzied star formation occurs because the galactic centre is forming deep inside a gravitational well of dark matter, an invisible form of matter that makes up the scaffolding upon which galaxies formed in the early Universe. A torrent of gas is flowing into the well and into the compact galaxy, sparking waves of star birth.

The Hubble GOODS North field (GOODS-N)

"They're very extreme environments," said Nelson. "It's like a medieval cauldron forging stars. There's a lot of turbulence, and it's bubbling. If you were in there, the night sky would be bright with young stars, and there would be a lot of dust, gas, and remnants of exploding stars. To actually see this happening is fascinating."

The sheer amount of gas and dust within an extreme star-forming region like this may explain why they have eluded astronomers until now. Bursts of star formation create dust, which builds up within the forming core and can block some starlight [3] — GOODS-N-774 was only just visible, even using the resolution and infrared capabilities of Hubble's Wide Field Camera 3.

video
Zoom into a distant galaxy core in the Hubble GOODS North field

"This galaxy seems to have been furiously forming stars for more than a billion years," adds Franx. "We have spotted it very early on in its life. Shortly after the time period we're looking at, we think that this core will have stopped forming stars, and that smaller galaxies will have merged with it over the next 10 billion years until it expanded and grew outwards in size. It would resemble one of the mammoth, sedate ellipticals we see today."

"We had been searching for this galaxy for years, and it's very exciting that we finally found it", says Dokkum, "The big challenge is to understand the physics driving the formation of such objects. The James Webb Space Telescope, Hubble's successor, will be able to help us find an answer."

Notes:

[1] The astronomers found the galaxy while poring over WFC3 images of thousands of galaxies catalogued in two large Hubble surveys of the distant Universe: 3D-HST and the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). They then used instruments at the W.M. Keck Observatory to measure the galaxy's distance from Earth, and to detect how fast the gas was moving, which confirmed its massive structure.

[2] Not all stars are the same mass as our Sun. The approximately 10 stars per year formed in the Milky Way will generally be less massive than our Sun.

[3] The dust build up in the compact galaxy obscures and reddens ultraviolet light from infant stars. The dust is absorbing and re-radiating that light as infrared light.

Notes for editors:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The science paper announcing the results will appear in the journal Nature on 27 August 2014. The international team of astronomers in this study consists of E. Nelson (Yale University, USA), P. van Dokkum (Yale University, USA), M. Franx (Leiden University, The Netherlands), G. Brammer (STScI, USA), I. Momcheva (Yale University, USA), N. M. Forster Schreiber (Max Planck Institute for Extraterrestrial Physics, Garching, Germany), E. da Cunha (Max Planck Institute for Astronomy, Heidelberg, Germany), L. Tacconi (Max Planck Institute for Extraterrestrial Physics, Garching, Germany), R. Bezanson (University of Arizona, USA), A. Kirkpatrick (University of Massachusetts, USA), J. Leja (Yale University, USA), H-W. Rix (Max Planck Institute for Astronomy, Heidelberg, Germany), R. Skelton (SAAO, South Africa), A. van der Wel (Max Planck Institute for Astronomy, Heidelberg, Germany), K. Whitaker (Goddard Space Center, USA), and S. Wuyts (Max Planck Institute for Extraterrestrial Physics, Garching, Germany).

Links:

Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

STScI release: http://hubblesite.org/newscenter/archive/releases/2014/37/

Science paper: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1418a.pdf

Images, Text, Credits: NASA, ESA, and E. Nelson (Yale University)/ Z. Levay and G. Bacon (Space Telescope Science Institute)/G. Illingworth (University of California, Santa Cruz), P. Oesch (University of California, Santa Cruz; Yale University), R. Bouwens and I. Labbé (Leiden University), and the Science Team/Video: NASA, ESA. Music: movetwo.

Greetings,Orbiter.ch

SOLAR IMPULSE 2 TEST FLIGHTS











Solar Impulse - Around the World patch.

Aug. 27, 2014

Solar Impulse - Around The World In A Solar Airplane

Since the solar airplane’s first flight in June, all the test flights have been successful, even if there are still a few improvements to be made on this experimental aircraft.

You may have noticed the vertical stabilizer shaking on the videos, a problem that our team is currently fixing.

Each test flight enables exploration of a different part of the flight envelope, with the ultimate objective of obtaining aircraft certification, thus opening the way for Bertrand Piccard and André Borschberg’s first flights!

Solar Impulse 2 over the lake of Neuchâtel (Switzerland)

In order to fix this problem, the engineering team has decided to develop a teeter control mechanism for each propeller, which should reduce the vibrations by allowing the propellers to adjust to the airflow.

Each of these modifications made to Solar Impulse 2 demonstrates how difficult a project like this is, its innovative nature, and the pioneering spirit shown every day by the entire team.

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

Image, Text, Credit: Solar Impulse.

Cheers, Orbiter.ch

INTEGRAL catches dead star exploding in a blaze of glory












ESA - Integral Mission patch.

27 August 2014

Astronomers using ESA’s Integral gamma-ray observatory have demonstrated beyond doubt that dead stars known as white dwarfs can reignite and explode as supernovae. The finding came after the unique signature of gamma rays from the radioactive elements created in one of these explosions was captured for the first time.

The explosions in question are known as Type Ia supernovae, long suspected to be the result of a white dwarf star blowing up because of a disruptive interaction with a companion star. However, astronomers have lacked definitive evidence that a white dwarf was involved until now. The ‘smoking gun’ in this case was evidence for radioactive nuclei being created by fusion during the thermonuclear explosion of the white dwarf star.

Supernova explosion

“Integral has all the capabilities to detect the signature of this fusion, but we had to wait for more than ten years for a once-in-a-lifetime opportunity to catch a nearby supernova,” says Eugene Churazov, from the Space Research Institute (IKI) in Moscow, Russia and the Max Planck Institute for Astrophysics,in Garching, Germany.

Although Type Ia supernovae are expected to occur frequently across the Universe they are rare occurrences in any one galaxy, with typical rates of one every few hundred years. 

Integral’s chance came on 21 January 2014, when students at the University College London’s teaching observatory at Mill Hill, UK detected a type Ia supernova, later named SN2014J, in the nearby galaxy M82.

According to the theory of such explosions, the carbon and oxygen found in a white dwarf should be fused into radioactive nickel during the explosion. This nickel should then quickly decay into radioactive cobalt, which would itself subsequently decay, on a somewhat longer timescale, into stable iron.

Because of its proximity – at a distance of about 11.5 million light-years from Earth, SN2014J is the closest of its type to be detected in decades – Integral stood a good chance of seeing the gamma rays produced by the decay. Within one week of the initial discovery, an observing plan to use Integral had been drawn-up and approved.

Supernova SN2014J in nearby galaxy M82

Using Integral to study the aftermath of the supernova explosion, scientists looked for the signature of cobalt decay – and they found it, in exactly the quantities that the models predicted.

“The consistency of the spectra, obtained by Integral 50 days after the explosion, with that expected from cobalt decay in the expanding debris of the white dwarf was excellent,” says Churazov, who is lead author of a paper describing this study and reported in the journal Nature.

With that confirmation in hand, other astronomers could begin to look into the details of the process. In particular, how the white dwarf is detonated in the first place.

White dwarfs are inert stars that contain up to 1.4 times the mass of the Sun squeezed into a volume about the same size as the Earth. Being inert, they can’t simply blow themselves up. Instead, astronomers believe that they leech matter from a companion star, which builds up on the surface until a critical total mass is reached. At that point, the pressure in the heart of the white dwarf triggers a catastrophic thermonuclear detonation.

Early Integral observations of SN2014J tell a somewhat different story, and have been the focus of a separate study, reported online in Science Express by Roland Diehl from the Max Planck Institute for Extraterrestrial Physics, Germany, and colleagues.

Diehl and his colleagues detected gamma rays from the decay of radioactive nickel just 15 days after the explosion. This was unexpected, because during the early phase of a Type Ia supernova, the explosion debris is thought to be so dense that the gamma rays from the nickel decay should be trapped inside.

Supernova explosion sequence (annotated)

“We were puzzled by this surprising signal, and some from the group even thought it must be wrong,” says Diehl. “We had long and ultimately very fruitful discussions about what might explain these data.”

A careful examination of the theory showed that the signal would have been hidden only if the explosion had begun in the heart of the white dwarf. Instead, Diehl and colleagues think that what they are seeing is evidence for a belt of gas from the companion star that must have built up around the equator of the white dwarf. This outer layer detonated, forming the observed nickel and then triggering the internal explosion that became the supernova.

“Regardless of the fine details of how these supernovae are triggered, Integral has proved beyond doubt that a white dwarf is involved in these stellar cataclysms,” says Erik Kuulkers, ESA’s Integral Project Scientist. “This clearly demonstrates that even after almost twelve years in operation, Integral is still playing a crucial role in unraveling some of the mysteries of the high-energy Universe.”  

Notes for editors:

56Co gamma-ray emission lines from the type Ia supernova SN2014J” by E. Churazov et al., is published in the 28 August 2014 issue of Nature; DOI: 10.1038/nature13672

“Early 56Ni decay γ rays from SN2014J suggest an unusual explosion” by R. Diehl et al., appeared online in Science Express on 31 July 2014; DOI: 10.1126/science.1254738

Some of the observations of SN2014J were obtained as part of an Integral Target of Opportunity programme led by Principal Investigator Jordi Isern (ICE-CSIC/IEEC, Spain). The Integral Project Scientist, Erik Kuulkers, made additional observing time available, on request of the Integral supernova community, to maximise the scientific return. This was supplemented by a contribution from the Russian guaranteed time on the recommendation of the Russian Integral Advisory Committee.

Type Ia supernovae are particularly important because they are used to gauge distances across much of the visible Universe. In the 1990s, their study led to the discovery of the cosmic acceleration that is now thought to be powered by a mysterious form of energy called ‘dark energy’. The Nobel Prize for Physics in 2011 was awarded to Saul Perlmutter, Adam Riess, and Brian Schmidt for their role in the discovery of dark energy.

The International Gamma-ray Astrophysics Laboratory Integral was launched on 17 October 2002. It is an ESA project with the instruments and a science data centre funded by ESA Member States (especially the Principal Investigator countries: Denmark, France, Germany, Italy, Spain and Switzerland), and with the participation of Russia and the USA. The mission is dedicated to the fine spectroscopy (E/∆E = 500) and fine imaging (angular resolution: 12 arcmin FWHM) of celestial gamma-ray sources in the energy range 15 keV to 10 MeV with concurrent source monitoring in the X-ray (4–35 keV) and optical (V-band, 550 nm) wavelengths.

More about Integral:

Integral in depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=21

Integral mission: http://sci.esa.int/integral/

Images, Text, Credits: ESA/ATG medialab/NASA/A. Goobar (Stockholm University)/Hubble Heritage Team (STScI/AURA).

Best regards, Orbiter.ch

The scientific program of Foton-M №4 ended

ROSCOSMOS logo.

08/27/2014

August 27 a meeting of the State Commission, which examined the results of scientific experiments aboard the spacecraft Foton-M № 4.

Foton-M spacecraft

Implementation of the program of scientific experiments on August 27 over. State Commission decided landing Foton-M № 4 today in the Orenburg region.

The launch of spacecraft Foton-M № 4 was held July 19, 2014 from launch pad number 31 Baikonur cosmodrome.

Launch of the Foton-M4 aboard Soyuz 2-1A on July 19, 2014

Foton-M is designed for microgravity experiments, providing reception of new knowledge on the physics of weightlessness and the refinement of manufacturing processes of semiconductor materials, biomedical products with improved performance, as well as conducting biological and biotechnological research.

Foton-M №4 landed in Orenburg region

The maximum term of the flight of the spacecraft Foton-M №4 is not more than 60 days.

Roscosmos Press Release: http://www.federalspace.ru/20875/

Images, Text, Credits: Roscosmos press service / ROSCOSMOS / Translation: Orbiter.ch Aerospace.

Cheers, Orbiter.ch

International Space Station reboost












ISS - International Space Station patch.

08/27/2014

August 27 at 12:37 MSK was the correction of the orbit of the International Space Station.

Orbit correction took place in the normal mode. According to the telemetry duration of propulsion cargo vehicle ATV-5 was 178.68 seconds. As a result, ISS has received the increment speed of 0.43 m / sec., Orbit height increased by 1 km.

video
ISS Reboost by ATV

Video above: NASA astronaut Don Pettit, Expedition 30 flight engineer, captured this video of engines of the Automated Transfer Vehicle being fired to reboost the International Space Station.

Correction was performed to create the conditions for landing in a predetermined area of the vehicle crew manned spacecraft "Soyuz TMA-12M" as part of the Russian Space Agency cosmonauts Alexander Skvortsov, Oleg Artemyev and NASA astronaut Steven Swanson. The crew will return to Earth September 11, 2014.

ROSCOSMOS Press Release: http://www.federalspace.ru/20874/

Video, Text, Credits: Roscosmos press service / NASA / Translation: Orbiter.ch Aerospace.

Greetings, Orbiter.ch

mardi 26 août 2014

Sentinel-1 poised to monitor motion








ESA - Sentinel-1 Mission logo.

Aug. 26, 2014

Although it was only launched a few months ago and is still being commissioned, the new Sentinel-1A radar satellite has already shown that it can be used to generate 3D models of Earth’s surface and will be able to closely monitor land and ice surface deformation.

As the first in a fleet of satellite missions for Europe’s Copernicus environmental monitoring programme, Sentinel-1A was launched on 3 April. It carries an advanced radar instrument to image Earth’s surface through cloud and rain, regardless of whether it is day or night.

New views from Sentinel-1A (Italy’s Gulf of Genoa)

Among its many applications it will routinely monitor shipping zones, map sea ice and provide information on winds and waves for marine traffic, track changes in the way land is being used, provide imagery for rapid response to disasters such as floods, and monitor uplift and subsidence.

The satellite reached its operational orbit on 7 August and just 12 days later, its radar images were used to generate ‘interferograms’ that map the topography of parts of Italy and Norway.

Etna slopes

Synthetic aperture radar interferometry – or InSAR – is a technique where two or more satellite radar images acquired over the same area are combined to produce an interferogram.

These are important products for mapping topography to produce ‘digital elevation models’ and to monitor surface deformation caused by, for example, mining, earthquakes, volcanic activity, melting permafrost and glacial flow.

The rainbow-coloured fringes in these new images demonstrate the excellent phase stability of Sentinel-1A’s radar instrument and image processor, as well as that the satellite is in its correct orbit and ready for delivering data for applications and science.

Radar vision

ESA’s Sentinel-1 Project Manager, Ramón Torres, said, “I’m delighted to see these first interferograms, demonstrating the excellent capabilities of Sentinel-1A’s radar instrument. They certainly show the satellite’s outstanding performance in synthetic aperture radar interferometry with its large 250 km-swath.”

Radar images are the best way of tracking land subsidence and structural damage. Systematic observations mean that ground movement barely noticeable in everyday life can be detected and closely monitored.

For example, the animation shows an area of northern Norway that is particularly prone to landslides. Large landslides that suddenly shift rock into the sea could potentially create tsunami-like waves. In 1810, such a wave destroyed a village, and, history shows that this kind of natural disaster occurs a couple of times every 100 years in Norway.

video
Norwegian fringes

InSAR is an important tool used by the Norwegian authorities to map rockslide hazards nationwide. The unprecedented coverage offered by the Sentinel-1 mission will significantly increase the value of InSAR data for this purpose.

The satellite passes over the same spot on the ground every 12 days. However, once its identical twin, Sentinel-1B, is launched in 2016, this will be cut to just six days, so that changes can be mapped even faster.

Norway relief

Pierre Potin, ESA’s Sentinel-1 Mission Manager, noted, “It is clear that Sentinel-1 will be a fantastic tool for interferometry-based applications.

“These first results are really promising, especially with the satellite’s mapping capability and the performance of the ground segment in mind. This will enable many operational services to be set up as well as advancing various scientific domains.” 

Related links:

Sentinel-1: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-1

Data access & technical information: https://sentinel.esa.int/web/sentinel/home

European Commission Copernicus site: http://www.copernicus.eu/

Northern Research Institute: http://norut.no/en

DLR–Remote Sensing Technology Institute: http://www.dlr.de/eoc/en/desktopdefault.aspx/tabid-5279/8913_read-16239/

DLR–Microwaves and Radar Institute: http://www.dlr.de/hr/en/desktopdefault.aspx

Scientific exploitation of operational missions: http://seom.esa.int/

Images, Video, Text, Credits: Copernicus data (2014)/ESA/DLR Remote Sensing Technology Institute/ATG medialab/Norut–SEOM Insarap study.

Greetings, Orbiter.ch

Best view yet of merging galaxies in distant Universe












ESA - Hubble Space Telescope logo.

26 August 2014

Hubble goes Sherlock Holmes

Merging galaxies in the distant Universe through a gravitational magnifying glass

Using the NASA/ESA Hubble Space Telescope and many other telescopes on the ground and in space, an international team of astronomers has obtained the best view yet of a collision that took place between two galaxies when the Universe was only half its current age. They enlisted the help of a galaxy-sized magnifying glass to reveal otherwise invisible detail. These new studies of the galaxy H-ATLAS J142935.3-002836 have shown that this complex and distant object looks like the well-known local galaxy collision, the Antennae Galaxies.

The famous fictional detective Sherlock Holmes used a magnifying lens to reveal barely visible but important evidence. Astronomers are now combining the power of many telescopes on Earth and in space [1] with a vastly larger form of lens to study a case of vigorous star formation in the early Universe.

How gravitational lensing acts as a magnifying glass — diagram

"While astronomers are often limited by the power of their telescopes, in some cases our ability to see detail is hugely boosted by natural lenses, created by the Universe," explains lead author Hugo Messias of the Universidad de Concepción (Chile) and the Centro de Astronomia e Astrofísica da Universidade de Lisboa (Portugal), "Einstein predicted in his theory of general relativity that, given enough mass, light does not travel in a straight line but will be bent in a similar way to light refracted by a normal lens."

These cosmic lenses are created by massive structures like galaxies and galaxy clusters, which deflect the light from objects behind them due to their strong gravity — an effect, called gravitational lensing. The magnifying properties of this effect allow astronomers to study objects that would not be visible otherwise and to directly compare local galaxies with much more remote ones, seen when the Universe was significantly younger.


Image above: Wide-field view of the sky around the gravitationally lensed galaxy merger H-ATLAS J142935.3-002836.

But for these gravitational lenses to work, the lensing galaxy, and the one far behind it, need to be very precisely aligned.

"These chance alignments are quite rare and tend to be hard to identify," adds Messias, "but, recent studies have shown that by observing at far-infrared and millimetre wavelengths we can find these cases much more efficiently."

H-ATLAS J142935.3-002836 (or just H1429-0028 for short) is one of these sources and was found in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). It is among the brightest gravitationally lensed objects in the far-infrared regime found so far, even though we are seeing it at a time when the Universe was just half its current age.

video
Zooming in on a gravitationally lensed galaxy merger in the distant Universe

Probing this object was at the limit of what is possible, so the international team of astronomers started an extensive follow-up campaign using the NASA/ESA Hubble Space Telescope alongside other space telescopes and some of the most powerful telescopes on the ground — including the Atacama Large Millimeter/submillimeter Array (ALMA), the Keck Observatory, the Karl Jansky Very Large Array (JVLA), and others. The different telescopes provided different views, which could be combined to get the best insight yet into the nature of this unusual object.

The Hubble and Keck images revealed a detailed gravitationally-induced ring of light around the foreground galaxy. These high resolution images also showed that the lensing galaxy is an edge-on disc galaxy — similar to our galaxy, the Milky Way — which obscures parts of the background light due to the large dust clouds it contains.

video
Artist's impression of gravitational lensing of a distant merger

"We need to observe with Hubble to find cases of gravitational lensing and to highlight in high resolution the clues left by these huge cosmic lenses", adds Rob Ivison, co-author and ESO's Director for Science

But, it is not possible to see past the large dust clouds of the foreground galaxy with Hubble. The obscuration was overcome by ALMA and the JVLA, since these two facilities observe the sky at longer wavelengths, which are unaffected by dust. Using the combined data the team discovered that the background system was actually an ongoing collision between two galaxies.

Further characterisation of the object was undertaken by ALMA which traced carbon monoxide, allowing for detailed studies of star formation mechanisms in galaxies and for the motion of the material in the galaxy to be measured. This confirmed that the lensed object is indeed an ongoing galactic collision forming hundreds of new stars each year, and that one of the colliding galaxies still shows signs of rotation; an indication that it was a disc galaxy just before this encounter.

The system of these two colliding galaxies resembles the Antennae Galaxies an object much closer to us than H1429-0028 and which Hubble has imaged several times before in stunning detail. This is a spectacular collision between two galaxies, which are believed to have had a disc structure in the past. While the Antennae system is forming stars with a total rate of only a few tens of times the mass of our Sun each year, H1429-0028 each year turns more than 400 times the mass of the Sun of gas into new stars each year.

Ivison concludes: "With the combined power of Hubble and these other telescopes we have been able to locate this very fortunate alignment, take advantage of the foreground galaxy's lensing effects and characterise the properties of this distant merger and the extreme starburst within it. It is very much a testament to the power of telescope teamwork."

Notes:

[1] The telescopes and surveys that were employed were: the NASA/ESA Hubble Space Telescope, ALMA, APEX, VISTA, the Gemini South telescope, the Keck-II telescope, the NASA Spitzer Space Telescope, the Jansky Very Large Array, CARMA, IRAM, and SDSS and WISE.

More information:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

This research was presented in a paper entitled "Herschel-ATLAS and ALMA HATLAS J142935.3-002836, a lensed major merger at redshift 1.027", by Hugo Messias et al., to appear online on 26 August 2014 in the journal Astronomy & Astrophysics.

The team is composed of Hugo Messias (Universidad de Concepción, Barrio Universitario, Chile, and Centro de Astronomia e Astrofísica da Universidade de Lisboa, Portugal), Simon Dye (School of Physics and Astronomy, University of Nottingham, UK), Neil Nagar (Universidad de Concepción, Barrio Universitario, Chile), Gustavo Orellana (Universidad de Concepción, Barrio Universitario, Chile), R. Shane Bussmann (Harvard-Smithsonian Center for Astrophysics, USA), Jae Calanog (Department of Physics & Astronomy, University of California, USA), Helmut Dannerbauer (Universität Wien, Institut für Astrophysik, Austria), Hai Fu (Astronomy Department, California Institute of Technology, USA), Edo Ibar (Pontificia Universidad Católica de Chile, Departamento de Astronomía y Astrofísica, Chile), Andrew Inohara (Department of Physics & Astronomy, University of California, USA), R. J. Ivison (Institute for Astronomy, University of Edinburgh, Royal Observatory, UK; ESO, Garching, Germany), Mattia Negrello (INAF, Osservatorio Astronomico di Padova, Italy), Dominik A. Riechers (Astronomy Department, California Institute of Technology, USA; Department of Astronomy, Cornell University, USA),Yun-Kyeong Sheen (Universidad de Concepción, Barrio Universitario, Chile), Simon Amber (The Open University, UK), Mark Birkinshaw (H H Wills Physics Laboratory, University of Bristol, UK; Harvard-Smithsonian Center for Astrophysics, USA), Nathan Bourne (School of Physics and Astronomy, University of Nottingham, UK), Dave L. Clements (Astrophysics Group, Imperial College London, UK), Asantha Cooray (Department of Physics & Astronomy, University of California, USA; Astronomy Department, California Institute of Technology, USA), Gianfranco De Zotti (INAF, Osservatorio Astronomico di Padova, Italy), Ricardo Demarco (Universidad de Concepción, Barrio Universitario, Chile), Loretta Dunne (Department of Physics and Astronomy, University of Canterbury, New Zealand; Institute for Astronomy, University of Edinburgh, Royal Observatory, UK), Stephen Eales (School of Physics and Astronomy, Cardiff University,UK) , Simone Fleuren (School of Mathematical Sciences, University of London, UK), Roxana E. Lupu (Department of Physics and Astronomy, University of Pennsylvania, USA), Steve J. Maddox (Department of Physics and Astronomy, University of Canterbury, New Zealand; Institute for Astronomy, University of Edinburgh, Royal Observatory, UK), Michał J. Michałowski (Institute for Astronomy, University of Edinburgh, Royal Observatory, UK), Alain Omont (Institut d'Astrophysique de Paris, UPMC Univ. Paris, France), Kate Rowlands (School of Physics & Astronomy, University of St Andrews, UK), Dan Smith (Centre for Astrophysics Research, Science & Technology Research Institute, University of Hertfordshire, UK), Matt Smith (School of Physics and Astronomy, Cardiff University,UK) and Elisabetta Valiante (School of Physics and Astronomy, Cardiff University, UK).

Links:

Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

ESO press release: http://www.eso.org/public/news/eso1426/

Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1426/eso1426a.pdf

Images, Text, Credits: NASA/ESA/ESO/M. Kornmesser/W. M. Keck Observatory/Digitized Sky Survey 2. Acknowledgement: Davide De Martin/Videos: NASA/ESA/W. M. Keck Observatory/Digitized Sky Survey 2/Hubble & ESO/M. Kornmesser. Music: movetwo.

Best regards, Orbiter.ch