Charting the Slow Death of the Universe

ESO - European Southern Observatory logo.

11 August 2015

GAMA survey releases first data at IAU General Assembly

An international team of astronomers studying more than 200 000 galaxies has measured the energy generated within a large portion of space more precisely than ever before. This represents the most comprehensive assessment of the energy output of the nearby Universe. They confirm that the energy produced in a section of the Universe today is only about half what it was two billion years ago and find that this fading is occurring across all wavelengths from the ultraviolet to the far infrared. The Universe is slowly dying.

The study involves many of the world’s most powerful telescopes, including ESO's VISTA and VST survey telescopes at the Paranal Observatory in Chile. Supporting observations were made by two orbiting space telescopes operated by NASA (GALEX and WISE) and another belonging to the European Space Agency (Herschel) [1].

The research is part of the Galaxy And Mass Assembly (GAMA) project, the largest multi-wavelength survey ever put together.

Galaxy images from the GAMA survey

“We used as many space and ground-based telescopes as we could get our hands on to measure the energy output of over 200 000 galaxies across as broad a wavelength range as possible,” says Simon Driver (ICRAR, The University of Western Australia), who heads the large GAMA team.

The survey data, released to astronomers around the world today, includes measurements of the energy output of each galaxy at 21 wavelengths, from the ultraviolet to the far infrared. This dataset will help scientists to better understand how different types of galaxies form and evolve.

All the energy in the Universe was created in the Big Bang, with some portion locked up as mass. Stars shine by converting mass back into energy, as described by Einstein’s famous equation E=mc2 [2]. The GAMA study sets out to map and model all of the energy generated within a large volume of space today and at different times in the past.

“While most of the energy sloshing around in the Universe arose in the aftermath of the Big Bang, additional energy is constantly being generated by stars as they fuse elements like hydrogen and helium together,” Simon Driver says. “This new energy is either absorbed by dust as it travels through the host galaxy, or escapes into intergalactic space and travels until it hits something, such as another star, a planet, or, very occasionally, a telescope mirror.”

The fact that the Universe is slowly fading has been known since the late 1990s, but this work shows that it is happening across all wavelengths from the ultraviolet to the infrared, representing the most comprehensive assessment of the energy output of the nearby Universe.

"The Universe will decline from here on in, sliding gently into old age. The Universe has basically sat down on the sofa, pulled up a blanket and is about to nod off for an eternal doze,” concludes Simon Driver.

The team of researchers hope to expand the work to map energy production over the entire history of the Universe, using a swathe of new facilities, including the world’s largest radio telescope, the Square Kilometre Array, which is due to be built in Australia and South Africa over the next decade.

The team will present this work at the International Astronomical Union XXIX General Assembly in Honolulu, Hawaii, on Monday 10 August 2015.

Notes:

[1] The telescopes and survey data used, in order of increasing wavelength, were: GALEX, SDSS, VST (KiDS survey), AAT, VISTA (VIKING survey)/UKIRT, WISE, Herschel (PACS/SPIRE).

[2] Much of the Universe’s energy output comes from nuclear fusion in stars, when mass is slowly converted into energy. Another major source is the very hot discs around black holes at the centres of galaxies, where gravitational energy is converted to electromagnetic radiation in quasars and other active galactic nuclei. Much longer wavelength radiation comes from huge dust clouds that are re-radiating the energy from stars within them.

More information:

This research will be presented in a paper entitled “Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV—far-IR) and the low-z energy budget”, by S. Driver et al., submitted to the journal Monthly Notices of the Royal Astronomical Society. It will also be the subject of a talk and press event at the IAU General Assembly in Hawaii on 10 August 2015.

The team is composed of Simon P. Driver (ICRAR, The University of Western Australia, Crawley, Western Australia, Australia [ICRAR]; University of St Andrews, United Kingdom), Angus H. Wright (ICRAR), Stephen K. Andrews (ICRAR), Luke J. Davies (ICRAR) , Prajwal R. Kafle (ICRAR), Rebecca Lange (ICRAR), Amanda J. Moffett (ICRAR) , Elizabeth Mannering (ICRAR), Aaron S. G. Robotham (ICRAR), Kevin Vinsen (ICRAR), Mehmet Alpaslan (NASA Ames Research Centre, Mountain View, California, United States), Ellen Andrae (Max Planck Institute for Nuclear Physics, Heidelberg, Germany [MPIK]), Ivan K. Baldry (Liverpool John Moores University, Liverpool, United Kingdom), Amanda E. Bauer (Australian Astronomical Observatory, North Ryde, NSW, Australia [AAO]), Steve Bamford (University of Nottingham, United Kingdom), Joss Bland-Hawthorn (University of Sydney, NSW, Australia), Nathan Bourne (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, United Kingdom), Sarah Brough (AAO), Michael J. I. Brown (Monash University, Clayton, Victoria, Australia), Michelle E. Cluver (The University of Western Cape, Bellville, South Africa), Scott Croom (University of Sydney, NSW, Australia), Matthew Colless (Australian National University, Canberra, ACT, Australia), Christopher J. Conselice (University of Nottingham, United Kingdom), Elisabete da Cunha (Macquarie University, Sydney NSW, Australia), Roberto De Propris (University of Turku, Piikkiö, Finland), Michael Drinkwater (Queensland University of Technology, Brisbane, Queensland, Australia), Loretta Dunne (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, United Kingdom; Cardiff University, Cardiff, United Kingdom), Steve Eales (Cardiff University, Cardiff, United Kingdom), Alastair Edge (Durham University, Durham, United Kingdom), Carlos Frenk (Durham University, Durham, United Kingdom), Alister W. Graham (Macquarie University, Sydney NSW, Australia), Meiert Grootes (MPIK), Benne W. Holwerda (Leiden Observatory, University of Leiden, Leiden, The Netherlands), Andrew M. Hopkins (AAO) , Edo Ibar (Universidad de Valparaso, Valparaiso, Chile), Eelco van Kampen (ESO, Garching, Germany), Lee S. Kelvin (Liverpool John Moores University, Liverpool, United Kingdom), Tom Jarrett (University of Cape Town, Rondebosch, South Africa), D. Heath Jones (Macquarie University, Sydney, NSW, Australia), Maritza A. Lara-Lopez (Universidad Nacional Automana de México, México), Angel R. Lopez-Sanchez (AAO), Joe Liske (Hamburger Sternwarte, Universität Hamburg, Hamburg, Germany), Jon Loveday (University of Sussex, Falmer, Brighton, United Kingdom), Steve J. Maddox (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, United Kingdom; Cardiff University, Cardiff, United Kingdom), Barry Madore (Observatories of the Carnegie Institution of Washington, Pasadena, California, United States [OCIW]), Martin Meyer (ICRAR) , Peder Norberg (Durham University, Durham, United Kingdom), Samantha J. Penny (University of Portsmouth, Portsmouth, United Kingdom), Stephen Phillipps (University of Bristol, Bristol, United Kingdom), Cristina Popescu (University of Central Lancashire, Preston, Lancashire), Richard J. Tuffs (MPIK), John A. Peacock (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, United Kingdom), Kevin A.Pimbblet (Monash University, Clayton, Victoria, Australia; University of Hull, Hull, United Kingdom), Kate Rowlands (University of St Andrews, United Kingdom), Anne E. Sansom (University of Central Lancashire, Preston, Lancashire), Mark Seibert (OCIW), Matthew W.L. Smith (Queensland University of Technology, Brisbane, Queensland, Australia), Will J. Sutherland (Queen Mary University London, London, United Kingdom), Edward N. Taylor (The University of Melbourne, Parkville, Victoria, Australia), Elisabetta Valiante (Cardiff University, Cardiff, United Kingdom), Lingyu Wang (Durham University, Durham, United Kingdom; SRON Netherlands Institute for Space Research, Groningen, The Netherlands), Stephen M. Wilkins (University of Sussex, Falmer, Brighton, United Kingdom) and Richard Williams (Liverpool John Moores University, Liverpool, United Kingdom).

The Galaxy and Mass Assembly Survey, or GAMA, is a collaboration involving nearly 100 scientists from more than 30 universities located in Australia, Europe and the United States.

ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

International Astronomical Union XXIX General Assembly: http://astronomy2015.org/

Galaxy And Mass Assembly (GAMA) project: http://www.gama-survey.org/

Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1533/eso1533a.pdf

Photos of VISTA and the VST: http://www.eso.org/public/images/archive/category/surveytelescopes/

Link to video fly-through of GAMA data: http://www.icrar.org/research/the-universe-is-dying

Image, Text, Credits: ESO/ICRAR/GAMA.

Greetings, Orbiter.ch

One Decade after Launch, Mars Orbiter Still Going Strong

NASA - Mars Reconnaissance Orbiter (MRO) logo.

August 11, 2015

Fast Facts:

- NASA's Mars Reconnaissance Orbiter was launched on Aug. 12, 2005

- MRO returns more data about Mars every week than all other Mars missions combined and supports Mars surface missions

- It has orbited Mars 40,000 times and returned 250 terabits of data so far (as much data as in nearly four months of nonstop high-definition video)

Ten years after launch, NASA's Mars Reconnaissance Orbiter (MRO) has revealed the Red Planet's diversity and activity, returning more data about Mars every week than all six other missions currently active there. And its work is far from over.

The workhorse orbiter now plays a key role in NASA's Journey to Mars planning. Images from the orbiter, revealing details as small as a desk, aid the analysis of potential landing sites for the 2016 InSight lander and Mars 2020 rover. Data from the orbiter will also be used as part of NASA's newly announced process to examine and select candidate sites where humans will first explore the Martian surface in the 2030s.

An Atlas V rocket launched the orbiter on an early Florida morning from Cape Canaveral Air Force Station on Aug. 12, 2005, propelling it on a course toward Mars.

"The most crucial event after launch was orbit insertion on March 10, 2006," said JPL's Dan Johnston, MRO project manager. "The 27-minute burn of the spacecraft's main engines, necessary for orbit capture, was scheduled for completion while the spacecraft was behind Mars, so we had to wait in suspense for confirmation that it went well. It did. As planned, the initial orbit was highly elliptical. Then we had nearly five months of aerobraking -- using controlled friction of more than 400 dips into the upper fringe of the atmosphere -- to shrink the orbit to a nearly circular shape."

Image above: Among the many discoveries by NASA's Mars Reconnaissance Orbiter since the mission was launched on Aug. 12, 2005, are seasonal flows on some steep slopes, possibly shallow seeps of salty water. This July 21, 2015, image from the orbiter's HiRISE camera shows examples within Mars' Valles Marineris. Image credits: NASA/JPL-Caltech/Univ. of Arizona.

MRO's primary science mission began in November 2006 and lasted for one Mars year, equivalent to about two Earth years. The orbiter has used six instruments to examine Mars' surface, subsurface and atmosphere. The spacecraft has been orbiting Mars at an altitude of about 186 miles (300 kilometers) above the Red Planet, passing near the north and south poles about 12 times a day.

"Mars Reconnaissance Orbiter has found evidence of diverse watery environments on early Mars, some more habitable than others," said the mission's project scientist, Rich Zurek of NASA's Jet Propulsion Laboratory, Pasadena, California. "MRO has discovered that Mars' south polar cap holds enough buried carbon-dioxide ice to double the planet's current atmosphere if it warmed. It's caught avalanches and dust storms in action. The spacecraft's longevity has made it possible to study seasonal and longer-term changes over four Martian years. These studies document activity such as moving dunes, freshly excavated impact craters -- some which expose subsurface ice -- and mysterious strips that darken and fade with the seasons and are best explained as brine flows."

Though it has already served longer than planned, the spacecraft could remain a cornerstone of NASA's Mars Exploration Program fleet for years to come.

Mars Reconnaissance Orbiter (MRO) spacecraft. Image Credits: NASA/JPL-Caltech

In addition to continuing to make its own discoveries about Mars, the mission delivers crucial support for surface-based missions. This support includes communication relay service and detailed observations of candidate landing sites for rovers and stationary landers past, present and future.

"Ten years after launch, MRO continues full science and relay operations," said Kevin Gilliland, spacecraft engineer for the mission at Lockheed Martin Space Systems, Denver. "We've kept our operations efficient. We've been able to bring back an astonishing amount of science data -- more than 250 terabits so far. Even after more than 40,000 orbits, the mission remains exciting, with new challenges such as taking close-up images of a passing comet last year and supporting next year's InSight landing."

The InSight mission will place a lander on Mars to investigate the deep interior of the Red Planet for clues about the formation and evolution of all rocky planets, including Earth. A maneuver two weeks ago altered MRO's orbit, as planned, to put it in position to provide communication support for InSight's Sept. 28, 2016, landing.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin built the orbiter and collaborates with JPL to operate it.

More information about NASA's journey to Mars is available online at: https://www.nasa.gov/topics/journeytomars

For more information about MRO, visit: http://www.nasa.gov/mro and http://mars.nasa.gov/mro

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

Greetings, Orbiter.ch

Cosmonauts Complete Russian Spacewalk

ISS - Expedition 44 Mission patch.

August 10, 2015

Image above: Image above: Cosmonaut Mikhail Kornienko is seen working outside the International Space Station in a Russian Orlan spacesuit. Image Credit: NASA TV.

International Space Station Expedition 44 Commander Gennady Padalka and Flight Engineer Mikhail Kornienko of the Russian Federal Space Agency completed a spacewalk lasting 5 hours, 31 minutes at 3:51 p.m. EDT. The spacewalkers rigged new equipment on the Russian segment of the complex and conducted a detailed photographic inspection of the exterior of the outpost.



Image above: Cosmonaut Mikhail Kornienko gets ready to close the hatch to the Pirs airlock ending the spacewalk. Image Credit: NASA TV.

This was the 188th spacewalk in support of space station assembly and maintenance, totaling 1,177 hours, or the equivalent of 49 days. Padalka’s ten spacewalks total 38 hours, 37 minutes. Kornienko’s two spacewalks total 12 hours, 13 minutes.

Russian cosmonauts conduct spacewalk outside ISS

While the cosmonauts were working outside the station, NASA astronauts Scott Kelly and Kjell Lindgren, along with Kimiya Yui of the Japan Aerospace Exploration Agency, sampled lettuce from the Veggie plant growth system on the International Space Station at 12:46 p.m. EDT. Lindgren first harvested half the crop and cleaned the “Outredgeous” red romaine lettuce.

Veggies in Space: Astronauts Sample Freshly Grown Lettuce

NASA is maturing Veggie technology aboard the station to provide future pioneers with a sustainable food supplement — a critical part of NASA’s journey to Mars. This is the first time a station-grown crop has officially been on the menu for station crew members. The remaining lettuce will be frozen on the station until it can be returned to Earth for scientific analysis.

ROSCOSMOS Press Release (in Russian):

РОСКОСМОС: ВЫХОД В ОТКРЫТЫЙ КОСМОС ПО РОССИЙСКОЙ ПРОГРАММЕ ЗАВЕРШЕН УСПЕШНО http://www.federalspace.ru/21631/

More details about the Veggie harvest is here: 

Meals Ready to Eat: Expedition 44 Crew Members Sample Leafy Greens Grown on Space Station: http://orbiterchspacenews.blogspot.ch/2015/08/meals-ready-to-eat-expedition-44-crew.html

For more information about Veggie, visit here: http://www.nasa.gov/mission_pages/station/research/experiments/383.html

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

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

Best regards, Orbiter.ch

NASA's Europa Mission Team Joins Forces for the First Time

NASA logo.

Aug. 10, 2015

They're united by a lofty goal -- to investigate whether Jupiter's moon Europa could harbor primitive life under its icy shell. Last week, a team of scientists and engineers for NASA's planned mission to Europa met for the first time at NASA's Jet Propulsion Laboratory in Pasadena, California, to begin turning that goal into reality.

After years of planning and hoping, the premier gathering was the final page of the team's origin story and the beginning of a new chapter that could last as long as two decades.

"We have a rare and wonderful opportunity with this mission to investigate whether Europa could be an abode for life," said Curt Niebur, Europa mission program scientist at NASA Headquarters in Washington, at the meeting's opening. "We're in the service of our colleagues, our scientific community, our country and our fellow human beings. It's a responsibility we take very seriously."

Image above: Artist's rendering of NASA's Europa mission spacecraft. Image Credits: NASA/JPL-Caltech.

The mission plan calls for a spacecraft to be launched to Jupiter in the 2020s, arriving in the distant planet's orbit after a journey of several years. The spacecraft would orbit the gas giant planet about every two weeks, providing many opportunities for close flybys of Europa. The mission plan includes 45 flybys, during which the spacecraft would image the moon's icy surface at high resolution and investigate its composition and the structure of its interior and icy shell. In late May, NASA announced the selection of instruments for the mission's scientific payload, while in June the mission formally entered the development phase known as formulation.

Thought to contain an ocean of liquid water beneath its icy surface, Europa is considered one of the most promising places in the solar system beyond Earth to search for signs of present-day life, in the form of simple organisms.

At the introductory meeting, players in the room included many stars in the field of planetary exploration. Some came fresh from leading roles in the recent successful flyby of Pluto by NASA's New Horizons mission. Several have worked together for decades, exploring Europa and other icy moons with NASA's Cassini, Galileo and Voyager missions.

Space Shorts Could Jupiter’s Moon Europa Have an Ocean

Video above: Dwarf planets are a lot like regular planets. What’s the big difference? Find out in 60 seconds.

In addition to its veteran explorers, the Europa mission also includes younger team members who've begun making their contributions to the field more recently. Together, the assembled team of scientists and spacecraft engineers made for a group filled with possibilities for collaboration.

"That's why we're here, in one room, at the very start of the project," said Robert Pappalardo, Europa project scientist at JPL. "So we can begin to function as one team, to understand the cross-cutting science issues we all face, and so we can use all of our tools together to understand Europa."

Mission engineers had already been hard at work for the past couple of years, developing the overall concept that eventually became NASA's mission to Europa. They are charged with designing the spacecraft and choreographing its flight plan, and -- of course -- building the complex robotic space probe. Their initial briefing to the scientists included information on how to design the mission for Jupiter's hazardous radiation environment, and plans for integrating the recently selected science instruments into the probe's overall architecture.

"The engineering team has already made great progress, and we're in excellent shape for this phase of the mission," Barry Goldstein, Europa project manager at JPL, reported to the team. "I couldn't be more excited about the work we've done and the road ahead."

Image above: The team behind NASA's mission to Europa at their first face-to-face meeting at JPL in August 2015. Image Credits: NASA/JPL-Caltech.

The top priority for the mission's first meeting was to begin the work of refining the mission's science, especially with regard to how the instruments can best work together to achieve NASA's main objective for Europa. "Your instruments were each selected separately," said Pappalardo, "But now we want to understand how they can best work together to achieve the overarching goal, which is to investigate the habitability of this icy ocean moon."

NASA's Jet Propulsion Laboratory manages the Europa mission for NASA's Science Mission Directorate in Washington. The multiple-flyby Europa mission concept was developed in partnership with the Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland.

For more information about NASA's mission to Europa, visit:
http://www.nasa.gov/europa

Related articles:

NASA’s Europa Mission Begins with Selection of Science Instruments: http://orbiterchspacenews.blogspot.ch/2015/05/nasas-europa-mission-begins-with.html

Related link:

Europa (Moon): http://www.nasa.gov/subject/3148/europa-moon

Images (mentioned), Video, Text, Credits: NASA/JPL/Preston Dyches/Tony Greicius.

Greetings, Orbiter.ch

Marshall Astrophysicists Study Intricate Activity of Solar X-ray Jets

NASA  Marshall Space Flight Center logo.

Aug. 10, 2015

The sun, our closest star, is quite an amazing celestial body. Not only is it the heart of and the largest object in our solar system, it’s also essential to life on Earth -- it drives our weather patterns, affects our water cycles and circulates our atmosphere. Scientists at NASA’s Marshall Space Flight Center in Huntsville, Alabama, study the sun in great detail daily at the National Space Science Technology Center in an effort to understand how Earth’s most important energy source operates.

“It’s really important for us to understand the star in our backyard,” said Marshall astrophysicist Alphonse Sterling. “It’s our closest laboratory where we can learn more about other stars and the universe.”

Sterling and Marshall astrophysicist Mitzi Adams’ most recent paper, detailing some of their discoveries, was published July 6 in Nature, science’s most highly cited interdisciplinary journal.

At the NSSTC, a research facility and collaborative think tank on the campus of the University of Alabama in Huntsville, Marshall scientists and engineers routinely team with their counterparts in industry and academia to perform cutting-edge research and development in Earth and space sciences.

For their article, Small-Scale Filament Eruptions as the Driver of Solar Coronal Hole X-ray Jets, Adams and Sterling teamed with UAH Research Scientists Ronald Moore and David Falconer.

Image above: Research by NASA’s Marshall Space Flight Center astrophysicists, published in Nature, presents a new explanation of how solar X-ray jets occur. These jets, explosions that erupt from the sun's surface expelling hot gas, could help explain the superheating of the sun’s corona. Image Credits: NASA/JAXA/Hinode.

Using data from the Hinode satellite, a NASA and Japanese Aerospace Exploration Agency joint mission, and the Solar Dynamics Observatory, the first mission of NASA’s Living With a Star Program, the team studied solar X-ray jets in the coronal holes of the sun. Solar X-ray jets are explosions that erupt from the sun's surface, expelling hot gas into the corona, the sun’s outer atmosphere.

“These jets are very significant,” said Sterling. “They could help us explain one of the long-standing mysteries of astrophysics -- the heating of the sun’s corona.”

The internal temperature of the sun can reach nearly 15,000,000 degrees Celsius. As you move outward, the temperature drops. At the photosphere, or the sun’s visible surface, the temperature is only 6,000 C. However, the corona can reach temperatures greater than 1,000,000 C.

“It’s really intriguing,” said Adams. “It’s like moving away from a fire and getting hotter. These jets could help explain the superheating.”

The team chose to examine jets in the solar coronal holes where the jets are more easily observed and occur an average of 60 times a day. The coronal holes also have a relatively simple magnetic geometry making the jets easier to study.

As Sterling, Adams and their teammates examined these jets, they noticed the generally accepted theory of how jets were created didn’t accurately explain what was occurring. The long-standing theory, the Emerging-Flux Model, explained that new flux coming up to the photosphere and its interaction with the photosphere’s complex magnetic topology created the jets.

“We were looking everywhere to find this flux emerging,” said Adams, in regards to an earlier study that set the stage for their current work. “Farther and farther back in time, we sifted through hours and hours of data searching for magnetic signatures, emergences that occurred at the right location to fit the model.”

No matter where she looked, Adams couldn’t find evidence of the emerging flux. Sharing her frustrations with Sterling, who has spent years working with filament eruptions, they began to find similarities with his previous work.

“After we finally realized what we were looking at, it became clear,” said Sterling. “These jets were being caused by filament eruptions -- very small, scaled down filament eruptions.”

Solar observation satellite Hinode. Image Credits: NASA/JAXA

A filament is a structure in the corona consisting of cool plasma supported by magnetic fields. Filaments can be very, very large -- more than 68,000 miles long, or 8.5 times longer than Earth’s diameter -- and appear as long threads stemming from the photosphere, suspended in the corona, similar to a loose stitch on a baseball.

Changes in magnetic fields around filaments can cause them to erupt and result in solar flares and coronal mass ejections (CMEs). CMEs can enhance the flow of the solar wind, affecting our planet's magnetic field and causing geomagnetic storms. In Earth's magnetic field, such disturbances can energize spectacular auroras, cause communications interference and induce overloads in electrical power grids and equipment.

The team believes the small-scale filaments were hidden in earlier studies. Just like in larger filaments, the plasma of the smaller filament is significantly cooler than the corresponding eruption. Earlier satellites recording the eruptions could not separate the two occurrences, essentially hiding the filament. Advances in technology with the Hinode and SDO made it possible to separate the filament from the eruption by observing the event at different wavelengths.

For the paper, they examined 20 coronal-hole solar X-ray jets occurring on the solar limb, or the sun’s edge. With the profile view on the limb, the team was able to clearly see the small-scale filaments. These “smaller” filaments are, on average, almost 5,000 miles in length, roughly the distance from New York to Hawaii.

“The important thing we learned in our observations is that things scale down,” said Adams. “As technology advances and we are allowed to see things in greater detail, we continue to learn more.”

Scientists first began X-ray observations of the sun on Skylab, America’s first space station, in the 1970s. “It took that wavelength to discover the new things we are seeing now. We keep making better and better observations at finer and finer scales, and as technology advances this will continue.”

“The observations of these jets involve stellar magnetic fields, plasmas and their interactions,” said Sterling. “These interactions are taking place all over our universe, and it is important for us to understand how these events, from the smallest to the largest, can affect us in our solar system and on Earth.”

To read the team’s article in Nature (subscription required), visit: 
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14556.html

For more information about the National Space Science Technology Center, visit: http://www.nasa.gov/centers/marshall/scienceandtechnology/nsstc.html

For more information about NASA's Marshall Space Flight Center, visit: 
http://www.nasa.gov/centers/marshall

Related links:

National Space Science Technology Center: http://www.nasa.gov/centers/marshall/scienceandtechnology/nsstc.html

University of Alabama in Huntsville: http://www.uah.edu/

Hinode satellite: http://www.nasa.gov/mission_pages/hinode/

Japanese Aerospace Exploration Agency (JAXA): http://global.jaxa.jp/

Solar Dynamics Observatory (SDO): http://sdo.gsfc.nasa.gov/

Skylab: https://www.nasa.gov/mission_pages/skylab

Images (mentioned), Text, Credits: NASA/Marshall Space Flight Center/Janet Anderson/Lee Mohon.

Greetings, Orbiter.ch

Darkness Descending

NASA / ESA - Cassini-Huygens Mission to Saturn & Titan patch.

Aug. 10, 2015

Saturn’s unusual appearance in this picture is a result of the planet being imaged via an infrared filter.

Infrared images can help scientists determine the location of clouds in the planet’s atmosphere.  In this image, Cassini’s wide-angle camera used a filter which is especially sensitive to infrared wavelengths that are absorbed by methane.  Methane is not a major component of Saturn’s atmosphere, but enough of it is present to make a difference in how much light is reflected by different clouds. The darker areas reveal clouds that are lower in the atmosphere, therefore under more methane. Bright areas on Saturn are higher altitude clouds. Scientists think that these lower-altitude clouds are in regions where “air” is descending while the higher-altitude clouds are in regions where air is rising. Thus, images like this one can help us map the vertical air movements on Saturn.

This view looks toward the unilluminated side of the rings from less than one degree from the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on May 25, 2015 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 890 nanometers.

The view was acquired at a distance of approximately 930,000 miles (1.5 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 99 degrees. Image scale is 55 miles (89 kilometers) per pixel.

Cassini spacecraft around Saturn

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org and http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images, Text, Credits: NASA/JPL-Caltech/Space Science Institute/Tony Greicius.

Greetings, Orbiter.ch

CERN - A superconducting shield for astronauts

CERN - European Organization for Nuclear Research logo / European Space Radiation Superconducting Shield (SR2S) logo.

August 9, 2015

Image above: Illustration image: A superconducting shield to protect astronauts. Image Credits: K. Anthony/CERN.

A team at CERN is working with the European Space Radiation Superconducting Shield (SR2S) project to develop a superconducting magnet that could protect astronauts from cosmic radiation during deep-space missions. The idea is to create an active magnetic field to shield spacecraft from high-energy particles.

The superconductor coils for the prototype magnet will be made of magnesium diboride (MgB₂), the same type of conductor that was developed in the form of wire for the High Luminosity Cold Powering project at CERN's Large Hadron Collider.

“In the framework of the project, we will test, in the coming months, a racetrack coil wound with an MgB₂ superconducting tape,” says Bernardo Bordini, coordinator of CERN activity in the framework of the SR2S project. “The prototype coil is designed to quantify the effectiveness of the superconducting magnetic shielding technology.”

Image above: Artistic representations of an active, magnetic, toroidal shield used for protecting astronauts from astroparticles during the transfer in orbit. Image Credits: Giorgina Colleoni & Valerio Calvelli.

During long-duration trips in space and in the absence of the magnetosphere that protects people living on Earth, astronauts are bombarded with high-energy cosmic rays that might cause a significant increase in the probability of various types of cancers. Because of this, exploration missions to Mars or other distant destinations will only become possible if an effective solution for adequately shielding astronauts is found. “If the prototype coil we will be testing produces successful results, we will have contributed important information to the feasibility of the superconducting magnetic shield,” says Amalia Ballarino, Superconductors and Superconducting Devices section leader.

There are many more challenges to overcome before a spacecraft shield can be built: various possible magnetic configurations need to be tested and compared and other key enabling technologies need to be developed. The MgB₂ superconductor seems to be very well placed to take part in this challenging adventure as, among its many advantages, there is also its ability to operate at higher temperatures (up to about 25 K) thus allowing the spacecraft to have a simplified cryogenic system. Watch this “space”!

Read a longer version of this article here: http://cds.cern.ch/journal/CERNBulletin/2015/32/News%20Articles/2038160?ln=en

Note:

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:

European Space Radiation Superconducting Shield: http://www.sr2s.eu/

CERN's Large Hadron Collider: http://home.web.cern.ch/topics/large-hadron-collider

Images (mentioned), Text, Credits: CERN/Antonella Del Rosso.

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