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  • richardmitnick 5:32 pm on May 23, 2016 Permalink | Reply
    Tags: , , NASA Goddard,   

    From Goddard: “NASA: Solar Storms May Have Been Key to Life on Earth” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    May 23, 2016
    Karen C. Fox
    NASA’s Goddard Space Flight Center, Greenbelt, Md.
    karen.c.fox@nasa.gov

    Solar eruption 2012 by NASA's Solar Dynamic Observatory SDO
    Solar eruption 2012 by NASA’s Solar Dynamic Observatory SDO

    Our sun’s adolescence was stormy—and new evidence shows that these tempests may have been just the key to seeding life as we know it.

    Some 4 billion years ago, the sun shone with only about three-quarters the brightness we see today, but its surface roiled with giant eruptions spewing enormous amounts of solar material and radiation out into space. These powerful solar explosions may have provided the crucial energy needed to warm Earth, despite the sun’s faintness. The eruptions also may have furnished the energy needed to turn simple molecules into the complex molecules such as RNA and DNA that were necessary for life. The research was published* in Nature Geoscience on May 23, 2016, by a team of scientists from NASA.


    Access mp4 video here .

    Understanding what conditions were necessary for life on our planet helps us both trace the origins of life on Earth and guide the search for life on other planets. Until now, however, fully mapping Earth’s evolution has been hindered by the simple fact that the young sun wasn’t luminous enough to warm Earth.

    “Back then, Earth received only about 70 percent of the energy from the sun than it does today,” said Vladimir Airapetian, lead author of the paper and a solar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “That means Earth should have been an icy ball. Instead, geological evidence says it was a warm globe with liquid water. We call this the Faint Young Sun Paradox. Our new research shows that solar storms could have been central to warming Earth.”

    Scientists are able to piece together the history of the sun by searching for similar stars in our galaxy. By placing these sun-like stars in order according to their age, the stars appear as a functional timeline of how our own sun evolved. It is from this kind of data that scientists know the sun was fainter 4 billion years ago. Such studies also show that young stars frequently produce powerful flares – giant bursts of light and radiation — similar to the flares we see on our own sun today. Such flares are often accompanied by huge clouds of solar material, called coronal mass ejections, or CMEs, which erupt out into space.

    NASA’s Kepler mission found stars that resemble our sun about a few million years after its birth.

    NASA/Kepler Telescope
    NASA/Kepler Telescope

    The Kepler data showed many examples of what are called “superflares” – enormous explosions so rare today that we only experience them once every 100 years or so. Yet the Kepler data also show these youngsters producing as many as ten superflares a day.

    While our sun still produces flares and CMEs, they are not so frequent or intense.

    What’s more, Earth today has a strong magnetic field that helps keep the bulk of the energy from such space weather from reaching Earth.

    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase
    Magnetosphere of Earth, original bitmap from NASA

    Space weather can, however, significantly disturb a magnetic bubble around our planet, the magnetosphere, a phenomenon referred to as geomagnetic storms that can affect radio communications and our satellites in space. It also creates auroras – most often in a narrow region near the poles where Earth’s magnetic fields bow down to touch the planet.

    Our young Earth, however, had a weaker magnetic field, with a much wider footprint near the poles.

    “Our calculations show that you would have regularly seen auroras all the way down in South Carolina,” says Airapetian. “And as the particles from the space weather traveled down the magnetic field lines, they would have slammed into abundant nitrogen molecules in the atmosphere. Changing the atmosphere’s chemistry turns out to have made all the difference for life on Earth.”

    The atmosphere of early Earth was also different than it is now: Molecular nitrogen – that is, two nitrogen atoms bound together into a molecule – made up 90 percent of the atmosphere, compared to only 78 percent today. As energetic particles slammed into these nitrogen molecules, the impact broke them up into individual nitrogen atoms. They, in turn, collided with carbon dioxide, separating those molecules into carbon monoxide and oxygen.

    The free-floating nitrogen and oxygen combined into nitrous oxide, which is a powerful greenhouse gas. When it comes to warming the atmosphere, nitrous oxide is some 300 times more powerful than carbon dioxide. The teams’ calculations show that if the early atmosphere housed less than one percent as much nitrous oxide as it did carbon dioxide, it would warm the planet enough for liquid water to exist.

    This newly discovered constant influx of solar particles to early Earth may have done more than just warm the atmosphere, it may also have provided the energy needed to make complex chemicals. In a planet scattered evenly with simple molecules, it takes a huge amount of incoming energy to create the complex molecules such as RNA and DNA that eventually seeded life.

    While enough energy appears to be hugely important for a growing planet, too much would also be an issue — a constant chain of solar eruptions producing showers of particle radiation can be quite detrimental. Such an onslaught of magnetic clouds can rip off a planet’s atmosphere if the magnetosphere is too weak. Understanding these kinds of balances help scientists determine what kinds of stars and what kinds of planets could be hospitable for life.

    “We want to gather all this information together, how close a planet is to the star, how energetic the star is, how strong the planet’s magnetosphere is in order to help search for habitable planets around stars near our own and throughout the galaxy,” said William Danchi, principal investigator of the project at Goddard and a co-author on the paper. “This work includes scientists from many fields — those who study the sun, the stars, the planets, chemistry and biology. Working together we can create a robust description of what the early days of our home planet looked like – and where life might exist elsewhere.”

    For more information about the Kepler mission, visit:

    http://www.nasa.gov/kepler

    *Science paper:
    Prebiotic chemistry and atmospheric warming of early Earth by an active young Sun

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
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  • richardmitnick 3:08 pm on May 22, 2016 Permalink | Reply
    Tags: , , NASA BARRELL, NASA Goddard   

    From Goddard: “NASA Mini-Balloon Mission Maps Migratory Magnetic Boundary” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    May 19, 2016
    Sarah Frazier
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    A BARREL balloon launches over Halley Research Station during the Antarctic summer of 2013-2014. The BARREL mission was created to observe precipitating electrons from Earth’s radiation belts, supplementing observations by NASA’s Van Allen Probes. During a January 2014 solar storm, BARREL measured solar electrons in addition to radiation belt electrons, allowing the team to map how parts of Earth’s magnetic field shift and change during a solar storm. Credits: NASA/BARREL

    2
    Six BARREL balloons flew above Antarctica during a January 2014 solar storm. The different-colored tracks trace out the paths of the balloons. Together, the measurements from these balloons showed how Earth’s magnetic field shifts during a solar storm. The BARREL balloons were launched from Antarctic research stations SANAE IV and Halley VI. Credits: NASA/Halford, et al.

    3
    Near Earth’s magnetic poles, some of Earth’s magnetic field – shown as red in this diagram – loops out into space and connects back to Earth. But some of Earth’s polar magnetic field connects directly to the sun’s magnetic field, shown here in white. Balloons from NASA’s BARREL mission mapped the boundary between these two types of magnetic connection as it shifted and changed during an event called a solar storm. Credits: NASA

    During the Antarctic summer of 2013-2014, a team of researchers released a series of translucent scientific balloons, one by one. The miniature membranous balloons – part of the Balloon Array for Radiation-belt Relativistic Electron Losses, or BARREL, campaign – floated above the icy terrain for several weeks each, diligently documenting the rain of electrons falling into the atmosphere from Earth’s magnetic field.

    Then in January 2014, BARREL’s observations saw something never seen before. During a fairly common space event called a solar storm – when a cloud of strongly magnetic solar material collides with Earth’s magnetic field – BARREL mapped for the first time how the storm caused Earth’s magnetic field to shift and move. The fields’ configuration shifted much faster than expected: on the order of minutes. These results were published* in the Journal of Geophysical Research on May 12, 2016. Understanding how our near-Earth space environment changes in response to solar storms helps us protect our technology in space.

    During this solar storm, three BARREL balloons were flying through parts of Earth’s magnetic field that directly connect a region of Antarctica to Earth’s north magnetic pole – these parts of the magnetic field are called closed field lines, because both ends are rooted on Earth. One BARREL balloon was on a field line with one end on Earth and one end connected to the sun’s magnetic field, an open field line. And two balloons switched back and forth between closed and open field lines throughout the solar storm, providing a map of how the boundary between open and closed field lines moved as a result of the storm.

    “It’s very difficult to model that open-closed boundary,” said Alexa Halford, a space scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This will help with our simulations of how magnetic fields change around Earth, because we’re able to state exactly where we saw this boundary.”

    We live in the extended atmosphere of a magnetically active star – which, in part, means that we’re constantly in the path of the sun’s outflow of charged particles, called the solar wind.

    Most of the solar wind particles are fairly slow, but even the fastest particles – accelerated to high speeds by explosions on the sun or pushed along by clouds of solar material – are deflected away from Earth’s surface by our planet’s magnetic field. Most of Earth’s magnetic field has a foot point in a region near Antarctica, called the south magnetic pole. Much of this magnetic field loops up out into space, but then connects back to Earth at the north magnetic pole, near the Arctic Circle. This looped part of the magnetic field – the closed magnetic field – creates a barrier against charged particles, repelling them from reaching Earth.

    But a smaller portion of Earth’s magnetic field is open, connecting to the sun’s magnetic field, instead of curving back toward Earth. It’s this open magnetic field that gives charged particles from the sun a path into Earth’s atmosphere. Once particles are stuck to an open field line, they can rocket down into the upper atmosphere to collide with neutral atoms, creating a type of aurora.

    The boundary between these open and closed regions of Earth’s magnetic field is anything but constant. Due to various causes – such as incoming clouds of solar material – the closed magnetic field lines can realign into open field lines and vice versa, changing the location of the boundary between open and closed magnetic field lines.

    Scientists have known that the open-closed boundary moves, but it’s hard to pinpoint exactly how, when, and how quickly it changes – and that’s where BARREL comes in. The six BARREL balloons flying during the January 2014 solar storm were able to map these changes, and they found something surprising – the open-closed boundary moves relatively quickly, changing location within minutes.

    BARREL was designed to study how electrons from Earth’s radiation belts – vast swaths of particles trapped in Earth’s magnetic field hundreds of miles above the surface – can make their way down into the atmosphere. The BARREL campaign is primarily tasked with supplementing observations by NASA’s Van Allen Probes, which are dedicated to studying these radiation belts.

    NASA Van Allen Probes
    NASA Van Allen Probes

    However, solar energetic electrons happen to be in the same energy range as those radiation belt electrons, meaning that BARREL can see both.

    “The scientists used balloon observations of solar particles entering Earth’s magnetic field to locate the outer boundary of Earth’s magnetic field, many tens of thousands of miles away,” said David Sibeck, a space scientist at Goddard and mission scientist at NASA for the Van Allen Probes. “This isn’t what BARREL was intended for, but it’s a wonderful bonus science return.”

    The Antarctic is dotted with ground-based systems that, like BARREL, can measure the influx of radiation belt electrons. But because of their design, these detectors are overwhelmed by solar protons – which generally far outnumber solar electrons during solar particle events – meaning they’re unable to differentiate between the particles that come from the sun versus those that come from the radiation belts. On the other hand, BARREL is finely tuned to see electrons, meaning that the accompanying barrage of solar protons doesn’t drown out the electrons in BARREL’s detectors.

    “Protons create signatures in a very small energy range, while electron signatures show up in a wide range of energies,” said Halford. “But the electron energies are usually well below the proton energy, so we can tell them apart.”

    It is possible – but unlikely – that complex dynamics in the magnetosphere gave the appearance that the BARREL balloons were dancing along this open-closed boundary. If a very fast magnetic wave was sending radiation belt electrons down into the atmosphere in short, stuttering bursts, it could appear that the balloons were switching between open and closed magnetic field lines.

    However, the particle counts measured by the two balloons on the open-closed boundary matched up to those observed by the other BARREL balloons – hovering on closed or open field lines only – strengthening the case that BARREL’s balloons were actually crossing the boundary between solar and terrestrial magnetic field.

    Related Links

    NASA’s BARREL website
    Paper in the Journal of Geophysical Research

    *Science paper:
    BARREL observations of a solar energetic electron and solar energetic proton event

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 6:40 pm on May 16, 2016 Permalink | Reply
    Tags: , , , NASA Goddard,   

    From Goddard via AGU: “Swept Up in the Solar Wind” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    AGU bloc
    AGU

    May 10, 2016
    Sarah Schlieder
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    This image from the ESA/NASA Solar and Heliospheric Observatory on June 15, 1999, shows streaks of bright light. This represents material streaming out from the sun (which is obscured in this picture by the central red disk so that it cannot overwhelm the image of the fainter material around it). Two other NASA spacecraft measured this material closer to Earth to better understand what causes this regular outflow, known as the solar wind, from the sun. Credits: NASA/SOHO

    ESA/SOHO
    ESA/SOHO

    2
    A constant outflow of solar material streams out from the sun, depicted here in an artist’s rendering. This solar wind is always passing by Earth. Credits: NASA Goddard’s Conceptual Image Lab/Greg Shirah

    From our vantage point on the ground, the sun seems like a still ball of light, but in reality, it teems with activity. Eruptions called solar flares and coronal mass ejections explode in the sun’s hot atmosphere, the corona, sending light and high energy particles out into space. The corona is also constantly releasing a stream of charged particles known as the solar wind.

    But this isn’t the kind of wind you can fly a kite in.

    Even the slowest moving solar wind can reach speeds of around 700,000 mph. And while scientists know a great deal about solar wind, the source of the slow wind remains a mystery. Now, a team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, has explored a detailed case study of the slow solar wind, using newly processed observations close to Earth to determine what in fact seeded that wind 93 million miles away, back on the sun. The team spotted tell-tale signs in the wind sweeping by Earth showing that it originated from a magnetic phenomenon known as magnetic reconnection. A paper* on these results was published April 22, 2016, in the journal Geophysical Research Letters.

    Knowing the source of the slow solar wind is important for understanding the space environment around Earth, as near-Earth space spends most of its time bathed in this wind. Just as it is important to know the source of cold fronts and warm fronts to predict terrestrial weather, understanding the source of the solar wind can help tease out space weather around Earth — where changes can sometimes interfere with our radio communications or GPS, which can be detrimental to guiding airline and naval traffic.

    Slow and Fast Solar Wind

    Fast solar wind — not surprisingly — can travel much faster than the slow wind at up to 1.7 million mph, but the most definitive difference between fast and slow solar wind is their composition. Solar wind is what’s known as a plasma, a heated gas made up of charged particles — primarily protons and electrons, with trace amounts of heavier elements such as helium and oxygen. The amount of heavy elements and their charge state, or number of electrons, differ between the two types of wind.

    “The composition and charge state of the slow solar wind is very different from that of fast solar wind,” said Nicholeen Viall, a solar scientist at Goddard. “These differences imply that they came from different places on the sun.”

    By studying its composition, scientists know that fast solar wind emanates from the interior of coronal holes — areas of the solar atmosphere where the corona is darker and colder. The slow solar wind, on the other hand, is associated with hotter regions around the equator, but just how the slow solar wind is released has not been clear.

    But the new results may have provided an answer.

    Tracking Down the Source: Magnetic Reconnection

    Magnetic reconnection can occur anywhere there are powerful magnetic fields, such as in the sun’s magnetic environment. Imagine a magnetic field line pointing in one direction and another field line nearby moving toward it pointing in the opposite direction. As they come together, the field lines will cancel and re-form, each performing a sort of U-turn and curving to move off in a perpendicular direction. The resulting new magnetic field lines create a large force — like a taut rubber band being released — that flings out plasma. This plasma is the slow solar wind.

    The team studied an interval of 90-minute periodic structures in the slow wind, and identified magnetic structures that are the telltale fingerprints of magnetic reconnection. They also found that each 90-minute parcel of slow wind showed an intriguing and repeating variability that could only be remnants of magnetic reconnection back at the sun.

    “We found that the density and charge state composition of the slow solar wind rises and falls every 90 minutes, varying from what is normally slow wind to what is considered fast,” Viall said. “But the speed was constant at a slow wind speed. This could only be created by magnetic reconnection at the sun, tapping into both fast and slow wind source regions.”

    Researchers first discovered the periodic density structures about 15 years ago using the Wind spacecraft — a satellite launched in 1994 to observe the space environment surrounding Earth. The scientists observed oscillations in the magnetic fields near Earth, known as the magnetosphere.

    3
    The WIND Satellite launched on November 1, 1994. The first of NASA’s Global Geospace Science (GGS) program.

    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase
    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase

    “It has been thought that the magnetosphere rang like a bell when the solar wind hit it with a sudden increase in pressure,” said Larry Kepko, a magnetospheric scientist at Goddard. “We went in for a closer look and found these periodicities in the solar wind. The magnetosphere was acting more like a drum than a bell.”

    But Wind only gave the researchers measurements of the slow solar wind’s density and velocity, and could not identify its source. For that, they needed composition data.

    Furthermore, in order to solve this problem, scientists from different disciplines needed to work together to come up with an explanation of the entire system. Kepko studies the magnetosphere, while Viall studies the sun. By observing what’s close to Earth and what’s happening at the sun, the team could determine the source of the slow solar wind.

    The scientists turned to NASA’s Advanced Composition Explorer. ACE launched in 1997 to study and measure the composition of several types of space material including the solar wind and cosmic rays. It can observe solar particles and helps researchers determine the elemental composition and speeds of solar wind.

    “Without the ACE data, we wouldn’t have been able to do this research,” Kepko said. “There’s no other instrument that gives us the information at the time resolution we needed.”

    The team is continuing to look at composition data to find other instances of the periodic density structures to determine if the source for all slow solar wind is magnetic reconnection. Their case study clearly shows that this particular event was the result of magnetic reconnection, but they wish to find other examples to show this is the most common mechanism for powering the slow solar wind.

    As the team gathers more information about magnetic reconnection and its effects near the sun, it will add to a growing body of knowledge about the phenomenon in general — because magnetic reconnection events take place throughout the universe.

    “If we can understand this phenomenon here, where we can actually measure the magnetic field, we can get a better handle on how these fundamental physics processes take place in other places in the universe,” Viall said.

    *Science paper: Geophysical Research Letters
    Implications of L1 observations for slow solar windformation by solar reconnection

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 3:27 pm on May 16, 2016 Permalink | Reply
    Tags: , , NASA Goddard   

    From Goddard: “MinXSS CubeSat Deployed From ISS to Study Sun’s Soft X-Rays” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    1
    On May 16, 2016, the NASA-funded MinXSS CubeSat deployed from an airlock of the International Space Station to enter an orbit around Earth. MinXSS observes soft X-rays from the sun — such X-rays can disturb the ionosphere and thereby hamper radio and GPS signals.
    Credits: ESA/NASA

    On May 16, 2016, the bread loaf-sized Miniature X-Ray Solar Spectrometer, or MinXSS, CubeSat deployed from an airlock on the International Space Station to begin its journey into space. The NASA-funded MinXSS studies emissions from the sun that can affect our communications systems.

    MinXSS will operate for up to 12 months. The CubeSat observes soft X-rays from the sun, which can disrupt Earth’s upper atmosphere and hamper radio and GPS signals traveling through the region. The intensity of the soft x-ray emissions emitted from the sun is continuously changing over a large range – with peak emission levels occurring during large eruptions on the sun called solar flares.

    MinXSS data will also help us understand the physics behind solar flares. The soft X-rays carry information about the temperature, density and chemical composition of material in the sun’s atmosphere, allowing scientists to trace how events like flares and other processes heat the surrounding material in the sun’s atmosphere – which are still being debated among solar scientists.

    ​CubeSats are a new, low-cost tool for space science missions. Instead of the traditional space science missions that carry a significant number of custom-built, state-of-the-art instruments, CubeSats are designed to take narrowly targeted scientific observations, with only a few instruments, often built from off-the-shelf components. For example, MinXSS uses a commercially purchased X-ray spectrometer for a detector and an extendable tape measure as a radio antenna. The MinXSS development program was funded by the NASA Science Mission Directorate CubeSat Initiative Program and implemented by the University of Colorado Boulder under the leadership of Principal Investigator Tom Woods.

    MinXSS was launched via the NASA CubeSat Launch Initiative program on Dec. 6, 2015, aboard Orbital ATK’s Cygnus spacecraft through NASA’s Commercial Resupply Services contract. Since its inception in 2010, the CSLI has selected more than 120 CubeSats for launch and deployed 43 small satellites as part of the agency’s Launch Services Program’s Educational Launch of Nanosatellite Missions.

    Related Link

    More information about MinXSS

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 12:06 pm on May 10, 2016 Permalink | Reply
    Tags: , , Miguel Román - From City Lights to Climate Change, NASA Goddard   

    From Goddard: “Miguel Román – From City Lights to Climate Change” People 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    May 10, 2016
    Elizabeth M. Jarrell
    NASA’s Goddard Space Flight Center

    1
    Credits: Amanda Voisard for the Washington Post

    Name: Miguel O. Román
    Title: Deputy Land Discipline Lead: Suomi National Polar-orbiting Partnership Mission
    Formal Job Classification: Research Physical Scientist
    Organization: Code 619, Terrestrial Information Systems Laboratory, Earth Science Division, Science Directorate

    From City Lights to Climate Change

    What do you do and what is most interesting about your role here at Goddard? How do you help support Goddard’s mission?

    On a typical day, I wake up and check my email to get the latest mission updates concerning the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Orbiting Partnership (NPP) satellite.

    NASA/Goddard Suomi NPP satellite
    NASA/Goddard Suomi NPP satellite

    VIIRS provides timely global coverage of many of Earth’s components including the land, ocean, atmosphere and cryosphere. I use these measurements to produce and distribute a suite of global land products to provide scientists and policy makers with useful information about issues such as water and land use, disaster management, agricultural problems, energy consumption and biodiversity conservation.

    How important is teamwork or collaboration with others?

    Ours is an international effort. NASA has 25 Earth-observing satellites orbiting the Earth right now. To get a complete picture of what is going on, it is very important for us to collaborate with other space agencies. We team with national agencies like the National Oceanographic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS); as well as international partners, such as ESA (the European Space Agency), the French space agency, the Japanese space agency and others, to ensure that we have sustained observations for very long periods of time. Polar-orbiting satellites usually last five to 10 years. As they age, they become more unpredictable. It is very important for us to integrate measurements from different satellites operated by NASA in concert with other space agencies.

    What is your role in interacting with other space agencies?

    I am the chair of the Land Product Validation (LPV) Subgroup of the Committee of Earth Observation of Satellites (CEOS) Working Group on Calibration and Validation (WGCV). Space agencies from the U.S., Europe, China, Japan and others are members of CEOS. Leadership of this committee changes every three years. Currently, NASA is currently lead coordinating agency for the CEOS land validation program.

    As a CEOS officer, I lead an international team of independent experts that are actively involved in global land product validation activities. Our goal is to ensure that all space agencies work together to devise agreed upon standards and techniques for measuring and assessing the quality and rigor of Earth observations. Our measurements are used as the basis of national and international climate policy, so they have to be accurate.

    What kinds of land measurements do you track and what can they tell us about the climate?

    We study many of the Earth’s processes over land. We treat the atmosphere as a noise that needs to be removed because we want to measure a satellite signal impacting the Earth’s surface. Different scientists need different data. At Goddard, we provide a portfolio of different data from which our users may select. We look at natural and human-induced changes.

    What are some of the natural changes being tracked?

    Natural changes include phenology, which is the study of vegetation dynamics, meaning how forests, meadows and crops change throughout the seasons. We track the pulse of vegetation from space by looking at the changes in vegetation structure and function over time.

    Our data is used to help predict when our Washington, D.C., cherry blossoms will bloom. We also look at the temperature record because it has to get hot. Then we look at how the vegetation is responding to that warming. The same principles apply to farming. Many farmers use our data, including our soil moisture satellite record, to time their planting season and to determine how much water and fertilizer they will need during extreme periods of drought and rain.

    We can even estimate the total area that is formed by leaves in a forest from space, which is called the leaf area index. This tells us what types of tree species dominate a particular forest. By collecting these measurements during long periods of time, the satellite data can indicate whether the forest canopy species composition is changing, which is really useful to help detect insect infestations in forests, as well as other disturbances related to climate change and human activities.

    What is your role in tracking the human-caused changes?

    My recent work has focused on the role that cities play in addressing climate change. As climate scientists, we want to improve our understanding of cities – what makes cities grow, change form, or become dense through time? Answering these questions can help us understand the drivers of energy use in cities, especially in developing and “data poor” countries. Almost 70 percent of the Earth’s carbon emissions comes from cities.

    Why are you interested in developing countries?

    Today’s developing countries will hold the megacities of tomorrow. We need to be able to predict the next metropolises 100 years from now. These countries are also in areas where we expect to see the largest impacts due to climate change. Many relief agencies, both in the U.S. and elsewhere, are helping these countries by providing them with the data and analytical tools needed to build more sustainable, livable, and low-carbon cities.

    We do our best to make sure that our satellite data reflects all communities on Earth – those which have electricity and those which lack access. An estimated 1.2 billion people, 17 percent of the global population, did not have access to electricity last year. We cannot ignore that many people, especially when we are trying to understand how human activities impact our planet. A key to solving the climate crisis is to be able to help these communities become more resilient and more sustainable.

    What is your educational background?

    I have an undergraduate degree in electrical engineering from the University of Puerto Rico. I have a master’s degree in systems engineering from Cornell University. I also have a Ph.D. in remote sensing from Boston University.

    Why did you become an engineer and what made you morph into a scientist?

    I was born and raised in Puerto Rico. My uncle was an engineer for the local phone company and he inspired me to pursue a career in STEM [science, technology, engineering and math]. At that time, to be successful in Puerto Rico, you could study to become an engineer and work as a line manager for a local biotech company or Bacardi Rum. When I was still in college, Goddard offered me a summer internship. That opportunity helped me looked beyond the things that happened on my local community and broadened my interests into some fascinating areas of scientific research.

    At Goddard, I noticed that scientists were the most enthusiastic about their work. The broader impact of NASA’s Earth science missions really appealed to me. These folks were changing the text books I once read as a young kid! From that point, I wanted to learn and understand the science behind climate change. So, I became a NASA scientist. I still believe that scientists have the most fun.

    When did you come to Goddard?

    I came to Goddard in 2003 as an intern. In 2009, after I finished my doctorate, Goddard offered me a permanent position. In between, Goddard gave me scholarships and fellowships to finish my degrees. I really feel that I became a part of Goddard in 2003.

    What do you look for in an intern?

    I host interns in our laboratory every summer. I try to find interns who are passionate about space and Earth science. Goddard is unique in that we have access to an incredible amount of space, airborne and ground Earth science assets. We have the planes, the rockets and the satellites. I want someone who will make the most of these assets.

    Goddard also offers first-seat access to a lot of observational data. We can sit right in front of that server, right in front of that global archive. We turn that data into useful products and distribute them globally to our partners. So, we have to see the big picture. I want an intern who can see the big picture.

    The one thing I always tell my interns is that they have to have a knack for turning raw pixels into useful data. That says it all.

    What are the qualities of a good scientist?

    You have to have integrity for the scientific process. You also have to be open about your research and understand that the best science is that which is crowd-sourced, the science where everybody contributes something. We are all standing on the shoulders of giants who paved the way for new science. A good scientist is a team player.

    What is the coolest thing you have done at Goddard?

    In 2014, our team detected an unexpected increase in our nocturnal visible satellite observations. We never thought that our instrument would be sensitive enough to detect the increase in light emissions during the holidays, but it turns out that our engineers built an instrument 100 times more sensitive than its required design. Our composite images of the Christmas lights went viral.

    Are you involved in fieldwork?

    I’ve done fieldwork all over the U.S. We’ve run experiments using airborne and ground-based measurements to calibrate and validate the satellite data records. I’ve taken soil moisture profiles in Chickasha, Oklahoma, measured leaf area index in Harvard Forest, Massachusetts, and installed solar radiation sensors in Howland, Maine. Most recently, I’ve helped deployed night sky brightness meters around 20 sites in Puerto Rico to measure light pollution levels.

    What is the most exciting thing that happened to you at Goddard?

    While I was an intern in 2004, I met this bright, young woman from Normandy, France, who was an international intern working in astronomy. We reunited as doctoral students at Boston University. We married in 2007. She now works for the Hubble Space Telescope Science Institute.

    She looks up at the galaxies and the interstellar medium. I look down at the Earth. We now have three kids, all big space enthusiasts. We have a big Dobsonian telescope in the backyard, as is tradition.

    Is there something surprising about you that people do not generally know?

    I love to cook. I married a French woman from a family of chefs with beautiful kitchens. We are an international family, so we love all kinds of food. The last special dish I made was beef Wellington and it turned out very well. At the end of the summer, I always invite my interns over for a five-course, gourmet dinner to thank them.

    See the full article here.

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
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  • richardmitnick 4:50 pm on April 26, 2016 Permalink | Reply
    Tags: "NASA Team Set to Fly Balloon Mission Seeking Evidence of Cosmological Inflation", , , Cosmic Bacground Radiation, NASA Goddard   

    From Goddard: “NASA Team Set to Fly Balloon Mission Seeking Evidence of Cosmological Inflation” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    This post is dedicated to D.O. the family rocket scientist. I hope that he sees it.

    April 26, 2016
    Lori Keesey
    NASA Goddard Space Flight Center

    Now that scientists have confirmed the existence of gravitational waves, a NASA team is set to search for a predicted signature of primordial gravitational waves that would prove the infant universe expanded far faster than the speed of light and began growing exponentially almost instantaneously after the Big Bang.

    1
    NASA scientist Al Kogut will search for evidence of cosmological inflation with a balloon-borne observatory called PIPER. Credits: NASA/W. Hrybyk

    Later this year, NASA scientist Al Kogut and his team at the Goddard Space Flight Center in Greenbelt, Maryland, will fly a breakthrough balloon payload — the Primordial Inflation Polarization Explorer, or PIPER — to find evidence of this accelerated expansion, called cosmological inflation.

    According to the theory, inflation would have generated gravitational waves, which are tiny perturbations in the fabric of space-time. These waves would have left an imprint in the polarization of the cosmic background radiation, the remnant light from the universe’s creation that bathes the sky in all directions.

    Scientific results from two NASA observatories that studied the background radiation revealed tantalizing clues that inflation did, in fact, occur. They found miniscule temperature differences in the afterglow radiation that pointed to density differences that eventually gave rise to the stars and galaxies seen today.

    Cosmic Background Radiation per Planck
    Cosmic Background Radiation per Planck

    The observations also showed that the density differences were remarkably uniform in all directions and that the geometry of the universe was flat — physical characteristics attributable to inflation.

    Although other theories also explain these dynamics, they do not explain the existence of primordial gravitational waves created when the universe inflated to astronomical dimensions. Despite repeated attempts, so far no one has discovered these waves or their telltale polarization signature — what cosmologists refer to as B-mode.

    Profound Consequences

    2
    This schematic shows the PIPER balloon payload and the layout of its instruments. Principal Investigator Al Kogut and his team plan a test run of the observatory in June, following up with the first of several science flights in September. Credits: NASA

    Should PIPER find the signature proving that the universe inflated from an infinitesimally small point to macroscopic scales within a nano-nano-nano-second of the Big Bang, the discovery would have profound consequences for cosmology and high-energy physics.

    While classical physics — such as Albert Einstein’s general theory of relativity — works perfectly for describing gravity on the macroscopic scale (where apples fall to the ground and Earth orbits the sun), it falls apart for calculating outcomes at subatomic, or quantum, scales. In addition to establishing inflation as a physical reality, PIPER’s discovery would give physicists the link between gravity and quantum mechanics.

    “If we find it, it will be direct observational proof that gravity obeys quantum mechanics,” Kogut said. “No one has yet worked out a consistent theory of quantum gravity; so observational evidence that gravity does obey quantum mechanics would be a huge development.”

    Flight Date Nears

    In June, the team plans to conduct a trial run with an engineering test unit with a scientific balloon flight from NASA’s Columbia Scientific Balloon Facility in Palestine, Texas. A follow up mission is scheduled for September with an overnight scientific balloon flight from NASA’s launch site in Fort Sumner, New Mexico, to obtain a view of the Northern Hemisphere. To study the remnant light from the Southern Hemisphere, the team plans to fly PIPER from Alice Springs, Australia; however, a launch has not yet been scheduled.

    PIPER ultimately may fly multiple times from the U.S. and Australia, soaring 120,000 feet above Earth where the atmosphere thins into the vacuum of space.

    State-of-the-Art Observatory

    PIPER is a state-of-the-art, highly sensitive observatory. About the size and weight of van, the observatory is equipped with twin telescopes, Goddard-developed superconducting detectors tuned to far-infrared wavelength bands, and a variable-delay polarization module to cleanly reveal polarized light.

    Because the polarization signal is at least 100 times fainter than the temperature signal detected by previous NASA missions, and even colder than the background radiation itself, PIPER must operate under super-cold temperatures to prevent instrument-generated heat from overwhelming the faint signal. As a result, the telescope, including the detectors and polarization modulator, will be placed inside a bucket dewar filled with liquid helium to maintain a frosty -457 degrees Fahrenheit.

    Difficult Measurement

    Despite its unparalleled sensitivity, PIPER’s mission is a difficult one.

    3
    Previous NASA missions identified E-mode polarization in the cosmic microwave background, the remnant light from the universe’s creation. The E-mode signal stems from a later period, when ultraviolet starlight began stripping electrons from hydrogen atoms, ionizing them. PIPER is seeking evidence of primordial gravitational waves and their telltale polarization signal — B-mode.
    Credits: NASA

    Previous NASA missions identified the E-mode signal, which exhibits a circular or radial arrangement across the sky. Its detection pointed to the time when light from the first stars ionized hydrogen atoms and liberated electrons from protons. The highly sought B-mode, on the other hand, prefers a twisty pattern.

    Gravitational Wave Background from BICEP 2
    BICEP 2’s errant Gravitational Wave Background [mostly from dust]shown here just to establish the sought after “twisty pattern”.

    Making detection challenging is the fact that different astrophysical phenomena will produce both.

    Astronomers have discovered this the hard way. In 2014, astronomers with the Background Imaging of Cosmic Extragalactic Polarization (BICEP2) experiment in the South Pole announced that they had detected the B-mode polarization.

    BICEP 2
    BICEP 2

    However, their euphoria was short-lived. A thorough analysis of data collected by the South Pole’s Keck Array and ESA’s Planck observatory revealed that the signal came instead from dust in the Milky Way.

    Keck Array
    Keck Array

    ESA/Planck
    ESA/Planck

    “BICEP2 didn’t have enough information,” explained Harvey Moseley, a Goddard cosmologist who has collaborated with Kogut in the development of technologies needed to probe the very early universe.

    Although BICEP2 had observed a 400-square-degree patch of sky near the Milky Way’s south pole — a region free of much of the dust that fills the star-studded disk — the telescope looked at only one frequency range. It tuned its instrument to 150 GHz, which is favorable for studies of the background radiation. To be truly cosmological in nature, however, the measurement should have been crosschecked at multiple frequencies.

    In contrast, PIPER will observe the whole sky at four different frequencies — 200, 270, 350, and 600 GHz — to discriminate between dust and primordial inflation, Kogut said. This assures that the team will be able to remove the dust signal.

    Furthermore, PIPER will fly from a high-altitude scientific balloon to avoid emissions from Earth’s atmosphere. If the gravitational waves exist, PIPER will detect their signature to a factor of three fainter than the lowest value predicted by inflationary models, Kogut said. In addition, the telescope will carry out its task 100 times faster than any ground-based observatory.

    Good News, Either Way

    Even if PIPER fails to detect the signature, the scientific community still would herald the mission a success. “It will be a big deal if they find the signal, but it also will be a big deal if PIPER can’t see it,” Moseley said. “It means that we need to come up with a different model of what happened in the early universe.”

    For more information about PIPER, visit: http://sciences.gsfc.nasa.gov/665/research/

    NASA’s scientific balloons offer low-cost, near-space access for scientific instruments in the 4,000-pound or more weight class for conducting scientific investigations in fields such as astrophysics, heliophysics and atmospheric research.

    NASA’s Wallops Flight Facility, in Virginia, manages the agency’s scientific balloon flight program, with 10 to 15 flights each year from launch sites worldwide. Orbital ATK, which operates the NASA Columbia Scientific Balloon Facility (CSBF), in Palestine, Texas, provides mission planning, engineering services and field operations for NASA’s scientific balloon program. The CSBF team has launched more than 1,700 scientific balloons in the over 35 years of operation.

    For more information on the balloon program, visit: http://www.nasa.gov/scientificballoons

    For more Goddard technology news, visit: https://gsfctechnology.gsfc.nasa.gov/newsletter/Current.pdf

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
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  • richardmitnick 4:12 pm on April 21, 2016 Permalink | Reply
    Tags: , , , NASA Goddard   

    From Goddard: “Microscopic “Timers” Reveal Likely Source of Galactic Space Radiation” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    April 21, 2016
    Karen C. Fox
    NASA Goddard Space Flight Center, Greenbelt, Maryland
    301-286-6284
    karen.c.fox@nasa.gov

    Most of the cosmic rays that we detect at Earth originated relatively recently in nearby clusters of massive stars, according to new results from NASA’s Advanced Composition Explorer (ACE) spacecraft.

    NASA ACE
    NASA ACE

    ACE allowed the research team to determine the source of these cosmic rays by making the first observations of a very rare type of cosmic ray that acts like a tiny timer, limiting the distance the source can be from Earth.

    Nebula in the constellation Carina, contains the central cluster of huge, hot stars, called NGC 3603. NASA ESA Hubble
    Nebula in the constellation Carina, contains the central cluster of huge, hot stars, called NGC 3603. NASA/ESA Hubble.

    “Before the ACE observations, we didn’t know if this radiation was created a long time ago and far, far away, or relatively recently and nearby,” said Eric Christian of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Christian is co-author of a paper on this research published April 21 in Science.

    Cosmic rays are high-speed atomic nuclei with a wide range of energy — the most powerful race at almost the speed of light. Earth’s atmosphere and magnetic field shield us from less-energetic cosmic rays, which are the most common. However, cosmic rays will present a hazard to unprotected astronauts traveling beyond Earth’s magnetic field because they can act like microscopic bullets, damaging structures and breaking apart molecules in living cells. NASA is currently researching ways to reduce or mitigate the effects of cosmic radiation to protect astronauts traveling to Mars.

    Cosmic rays are produced by a variety of violent events in space. Most cosmic rays originating within our solar system have relatively low energy and come from explosive events on the Sun, like flares and coronal mass ejections. The highest-energy cosmic rays are extremely rare and are thought to be powered by massive black holes gorging on matter at the center of other galaxies. The cosmic rays that are the subject of this study come from outside our solar system but within our Galaxy and are called galactic cosmic rays. They are thought to be generated by shock waves from exploding stars called supernovae.

    Supernova remnant Crab nebula. NASA/ESA Hubble
    Supernova remnant Crab nebula. NASA/ESA Hubble

    The galactic cosmic rays detected by ACE that allowed the team to estimate the age of the cosmic rays, and the distance to their source, contain a radioactive form of iron called Iron-60 (60Fe). It is created inside massive stars when they explode and then blasted into space by the shock waves from the supernova. Some 60Fe in the debris from the destroyed star is accelerated to cosmic-ray speed when another nearby massive star in the cluster explodes and its shock wave collides with the remnants of the earlier stellar explosion.

    60Fe galactic cosmic rays zip through space at half the speed of light or more, about 90,000 miles per second. This seems very fast, but the 60Fe cosmic rays won’t travel far on a galactic scale for two reasons. First, they can’t travel in straight lines because they are electrically charged and respond to magnetic forces. Therefore they are forced to take convoluted paths along the tangled magnetic fields in our Galaxy. Second, 60Fe is radioactive and over a period of about 2.6 million years, half of it will self-destruct, decaying into other elements (Cobalt-60 and then Nickel-60). If the 60Fe cosmic rays were created hundreds of millions of years or more ago, or very far away, eventually there would be too little left for the ACE spacecraft to detect.

    “Our detection of radioactive cosmic-ray iron nuclei is a smoking gun indicating that there has likely been more than one supernova in the last few million years in our neighborhood of the Galaxy,” said Robert Binns of Washington University, St. Louis, Missouri, lead author of the paper.

    “In 17 years of observing, ACE detected about 300,000 galactic cosmic rays of ordinary iron, but just 15 of the radioactive Iron-60,” said Christian. “The fact that we see any Iron-60 at all means these cosmic ray nuclei must have been created fairly recently (within the last few million years) and that the source must be relatively nearby, within about 3,000 light years, or approximately the width of the local spiral arm in our Galaxy.” A light year is the distance light travels in a year, almost six trillion miles. A few thousand light years is relatively nearby because the vast swarm of hundreds of billions of stars that make up our Galaxy is about 100,000 light years wide.

    There are more than 20 clusters of massive stars within a few thousand light years, including Upper Scorpius (83 stars), Upper Centaurus Lupus (134 stars), and Lower Centaurus Crux (97 stars). These are very likely major contributors to the 60Fe that ACE detected, owing to their size and proximity, according to the research team.

    ACE was launched on August 25, 1997 to a point 900,000 miles away between Earth and the Sun where it has acted as a sentinel, detecting space radiation from solar storms, the Galaxy, and beyond. This research was funded by NASA’s ACE program.

    Additional co-authors on this paper were: Martin Israel and Kelly Lave at Washington University, St. Louis, Missouri; Alan Cummings, Rick Leske, Richard Mewaldt and Ed Stone at Caltech in Pasadena, California; Georgia de Nolfo and Tycho von Rosenvinge at Goddard; and Mark Wiedenbeck at NASA’s Jet Propulsion Laboratory in Pasadena, California.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
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  • richardmitnick 9:15 pm on April 5, 2016 Permalink | Reply
    Tags: , , NASA Goddard,   

    From Goddard: “NASA’s New Horizons Fills Gap in Space Environment Observations” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    April 4, 2016
    Sarah Frazier
    sarah.a.frazier@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    When NASA’s New Horizons sped past Pluto on July 14, 2015, it took the best-ever pictures of the rocky world’s surface, giving us new insight into its geology, composition and atmosphere. These stunning images are the most famous result of New Horizons, but the spacecraft also sent back over three years’ worth of measurements of the solar wind – the constant flow of solar particles that the sun flings out into space – from a region that has been visited by only a few spacecraft.

    This unprecedented set of observations give us a peek into an almost entirely unexplored part of our space environment – filling a crucial gap between what other missions see closer to the sun and what the Voyager spacecraft see further out. A new study to appear in The Astrophysical Journal Supplement lays out New Horizons’ observations of the solar wind ions that it encountered on its journey.

    1
    Space environment data collected by New Horizons over a billion miles of its journey to Pluto will play a key role in testing and improving models of the space environment throughout the solar system. This visualization is one example of such a model: It shows the simulated space environment out to Pluto a few months before New Horizons’ closest approach. Drawn over the model is the path of New Horizons up to 2015, as well as the current direction of the two Voyager spacecraft – which are currently at three or four times New Horizons’ distance from the sun. The solar wind that New Horizons encountered will reach the Voyager spacecraft about a year later.
    Credits: NASA’s Goddard Space Flight Center Scientific Visualization Studio, the Space Weather Research Center (SWRC) and the Community-Coordinated Modeling Center (CCMC), Enlil and Dusan Odstrcil (GMU)

    Not only does the New Horizons data provide new glimpses of the space environment of the outer solar system, but this information helps round out our growing picture of the sun’s influence on space, from near-Earth effects to the boundary where the solar wind meets interstellar space. The new data shows particles in the solar wind that have picked up an initial burst of energy, an acceleration boost that kicks them up just past their original speed. These particles may be the seeds of extremely energetic particles called anomalous cosmic rays. When these super-fast, energetic rays travel closer to Earth, they can pose a radiation hazard to astronauts. Further away, at lower energies, the rays are thought to play a role at shaping the boundary where the solar wind hits interstellar space – the region of our solar system that Voyager 2 is currently navigating and observing.

    Studying the Solar Wind

    2
    Space environment data collected by New Horizons over a billion miles of its journey to Pluto will play a key role in testing and improving models of the space environment throughout the solar system. This visualization is one example of such a model: It shows the simulated space environment out to Pluto a few months before New Horizons’ closest approach.
    Credits: NASA’s Goddard Space Flight Center Scientific Visualization Studio, the Space Weather Research Center (SWRC) and the Community-Coordinated Modeling Center (CCMC), Enlil and Dusan Odstrcil (GMU)

    View full video on YouTube,

    Though space is about a thousand times emptier than even the best laboratory vacuums on Earth, it’s not completely devoid of matter – the sun’s constant outflow of solar wind fills space with a thin and tenuous wash of particles, fields, and ionized gas known as plasma. This solar wind, along with other solar events like giant explosions called coronal mass ejections, influences the very nature of space and can interact with the magnetic systems of Earth and other worlds. Such effects also change the radiation environment through which our spacecraft – and, one day, our astronauts headed to Mars – travel.

    New Horizons measured this space environment for over a billion miles of its journey, from just beyond the orbit of Uranus to its encounter with Pluto.

    “The instrument was only scheduled to power on for annual checkouts after the Jupiter flyby in 2007,” said Heather Elliott, a space scientist at the Southwest Research Institute in San Antonio, Texas, and lead author on the study. “We came up with a plan to keep the particle instruments on during the cruise phase while the rest of the spacecraft was hibernating and started observing in 2012.”

    This plan yielded three years of near-continuous observations of the space environment in a region of space where only a handful of spacecraft have ever flown, much less captured detailed measurements.

    “This region is billions of cubic miles, and we have a handful of spacecraft that have passed through every decade or so,” said Eric Christian, a space scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who studies what’s called the heliosphere – the region of our solar system dominated by the solar wind – but was not involved with this study. “We learn more from every one.”

    Since the sun is the source of the solar wind, events on the sun are the primary force that shapes the space environment. Shocks in the solar wind – which can create space weather, such as auroras, on worlds with magnetic fields – are created either by fast, dense clouds of material called coronal mass ejections, or CMEs, or by the collision of two different-speed solar wind streams. These individual features are discernible in the inner solar system – but New Horizons didn’t see the same level of detail.

    The New Horizons data show that the space environment in the outer solar system has less detailed structure than space closer to Earth, since smaller structures tend to be worn down or clump together as they travel outwards, creating fewer – but bigger – features.

    “At this distance, the scale size of discernible structures increases, since smaller structures are worn down or merge together,” said Elliott. “It’s hard to predict if the interaction between smaller structures will create a bigger structure, or if they will flatten out completely.”

    Subtler signs of the sun’s influence are also harder to spot in the outer solar system. Characteristics of the solar wind – including speed, density, and temperature – are shaped by the region of the sun it flows from. As the sun and its different wind-producing regions rotate, patterns form. New Horizons didn’t see patterns as defined as they are when closer to the sun, but nevertheless it did spot some structure.

    “Speed and density average together as the solar wind moves out,” said Elliott. “But the wind is still being heated by compression as it travels, so you can see evidence of the sun’s rotation pattern in the temperature even in the outer solar system.”

    Finding the Origins of Space Radiation Hazards

    The New Horizons observations also show what may be the starting seeds of the extremely energetic particles that make up anomalous cosmic rays. Anomalous cosmic rays are observed near Earth and can contribute to radiation hazard for astronauts, so scientists want to better understand what causes them.

    The seeds for these energetic, super-fast particles may also help shape the boundary where the solar wind meets interstellar space. Anomalous cosmic rays have been observed by the two Voyager spacecraft out near these boundaries, but only in their final stages, leaving questions as to the exact location and mechanism of their origins.
    measurement of seed particles for anomalous cosmic rays in the solar wind.

    3
    This figure shows solar wind observations measured by New Horizons from Jan. 1 to Aug. 25, 2015. This measurement of seed particles for anomalous cosmic rays in the solar wind is completely new in this region of space and is key for interpreting Voyager data further out in the interstellar boundary region. Points closer to the top of the graph correspond to higher-energy particles, and red and yellow colors show a larger number of particles hitting the detector. The particle instruments were shut down during certain spacecraft operations and trajectory maneuvers, resulting in brief data gaps. Credits: NASA/New Horizons/SwRI

    “The Voyagers can’t measure these seed particles, only the outcome,” said Christian. “So with New Horizons going into that region, this blank patch in the observations is being filled in with data.”

    Filling in such a blank patch will help scientists better understand the way such particles move and affect the space environment around them, helping to interpret what Voyager is seeing on its journey.

    Comparing New Horizons to Observations and Models

    Since New Horizons is one of the very few spacecraft that has explored the space environment in the outer solar system, lack of corroborating data meant that a key part of Elliott’s work was simply calibrating the data. Her work was supported by the Heliophysics Research and Analysis program.

    She calibrated the observations with pointing information from New Horizons, the results of extensive tests on the laboratory version of the instrument, and comparison with data from the inner solar system. NASA’s Advanced Composition Explorer, or ACE, and NASA’s Solar and Terrestrial Relations Observatory, or STEREO, for example, observe the space environment near Earth’s orbit, allowing scientists to capture a snapshot of solar events as they head towards the edges of the solar system. But because the space environment in the outer solar system is relatively unexplored, it wasn’t clear how those events would develop. The only previous information on space in this region was from Voyager 2, which traveled through roughly the same region of space as New Horizons, although about a quarter of a century earlier.

    “There are similar characteristics between what was seen by New Horizons and Voyager 2, but the number of events is different,” said Elliott. “Solar activity was much more intense when Voyager 2 traveled through this region.”

    Now, with two data sets from this region, scientists have even more information about this distant area of space. Not only does this help us characterize the space environment better, but it will be key for scientists testing models of how the solar wind propagates throughout the solar system. In the absence of a constant sentinel measuring the particles and magnetic fields in space near Pluto, we rely on simulations – not unlike terrestrial weather simulations – to model space weather throughout the solar system. Before New Horizons passed Pluto, such models were used to simulate the structure of the solar wind in the outer solar system. With a calibrated data set in hand, scientists can compare the reality to the simulations and improve future models.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 9:20 pm on February 26, 2016 Permalink | Reply
    Tags: , , NASA Goddard, ,   

    From NASA Goddard: “NASA’s IBEX Observations Pin Down Interstellar Magnetic Field” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    Feb. 26, 2016
    Sarah Frazier
    sarah.a.frazier@nasa.gov
    NASA’s Goddard Space Flight Center

    Immediately after its 2008 launch, NASA’s Interstellar Boundary Explorer, or IBEX, spotted a curiosity in a thin slice of space: More particles streamed in through a long, skinny swath in the sky than anywhere else.

    NASA IBEX
    IBEX

    The origin of the so-called IBEX ribbon was unknown – but its very existence opened doors to observing what lies outside our solar system, the way drops of rain on a window tell you more about the weather outside.

    Now, a new study uses IBEX data and simulations of the interstellar boundary – which lies at the very edge of the giant magnetic bubble surrounding our solar system called the heliosphere – to better describe space in our galactic neighborhood. The paper, published Feb. 8, 2016, in The Astrophysical Journal Letters, precisely determines the strength and direction of the magnetic field outside the heliosphere. Such information gives us a peek into the magnetic forces that dominate the galaxy beyond, teaching us more about our home in space.

    Inner heliosheath
    (Artist concept) Far beyond the orbit of Neptune, the solar wind and the interstellar medium interact to create a region known as the inner heliosheath, bounded on the inside by the termination shock, and on the outside by the heliopause. Credits: NASA/IBEX/Adler Planetarium

    The new paper is based on one particular theory of the origin of the IBEX ribbon, in which the particles streaming in from the ribbon are actually solar material reflected back at us after a long journey to the edges of the sun’s magnetic boundaries. A giant bubble, known as the heliosphere, exists around the sun and is filled with what’s called solar wind, the sun’s constant outflow of ionized gas, known as plasma. When these particles reach the edges of the heliosphere, their motion becomes more complicated.

    “The theory says that some solar wind protons are sent flying back towards the sun as neutral atoms after a complex series of charge exchanges, creating the IBEX ribbon,” said Eric Zirnstein, a space scientist at the Southwest Research Institute [SwRI] in San Antonio, Texas, and lead author on the study. “Simulations and IBEX observations pinpoint this process – which takes anywhere from three to six years on average – as the most likely origin of the IBEX ribbon.”

    Outside the heliosphere lies the interstellar medium, with plasma that has different speed, density, and temperature than solar wind plasma, as well as neutral gases. These materials interact at the heliosphere’s edge to create a region known as the inner heliosheath, bounded on the inside by the termination shock – which is more than twice as far from us as the orbit of Pluto – and on the outside by the heliopause, the boundary between the solar wind and the comparatively dense interstellar medium.

    Some solar wind protons that flow out from the sun to this boundary region will gain an electron, making them neutral and allowing them to cross the heliopause. Once in the interstellar medium, they can lose that electron again, making them gyrate around the interstellar magnetic field. If those particles pick up another electron at the right place and time, they can be fired back into the heliosphere, travel all the way back toward Earth, and collide with IBEX’s detector. The particles carry information about all that interaction with the interstellar magnetic field, and as they hit the detector they can give us unprecedented insight into the characteristics of that region of space.

    “Only Voyager 1 has ever made direct observations of the interstellar magnetic field, and those are close to the heliopause, where it’s distorted,” said Zirnstein.

    NASA Voyager 1
    Voyager 1

    “But this analysis provides a nice determination of its strength and direction farther out.”

    The directions of different ribbon particles shooting back toward Earth are determined by the characteristics of the interstellar magnetic field. For instance, simulations show that the most energetic particles come from a different region of space than the least energetic particles, which gives clues as to how the interstellar magnetic field interacts with the heliosphere.

    For the recent study, such observations were used to seed simulations of the ribbon’s origin. Not only do these simulations correctly predict the locations of neutral ribbon particles at different energies, but the deduced interstellar magnetic field agrees with Voyager 1 measurements, the deflection of interstellar neutral gases, and observations of distant polarized starlight.

    However, some early simulations of the interstellar magnetic field don’t quite line up. Those pre-IBEX estimates were based largely on two data points – the distances at which Voyagers 1 and 2 crossed the termination shock.

    “Voyager 1 crossed the termination shock at 94 astronomical units, or AU, from the sun, and Voyager 2 at 84 AU,” said Zirnstein. One AU is equal to about 93 million miles, the average distance between Earth and the sun. “That difference of almost 930 million miles was mostly explained by a strong, very tilted interstellar magnetic field pushing on the heliosphere.”

    But that difference may be accounted for by considering a stronger influence from the solar cycle, which can lead to changes in the strength of the solar wind and thus change the distance to the termination shock in the directions of Voyager 1 and 2. The two Voyager spacecraft made their measurements almost three years apart, giving plenty of time for the variable solar wind to change the distance of the termination shock.

    “Scientists in the field are developing more sophisticated models of the time-dependent solar wind,” said Zirnstein.

    The simulations generally jibe well with the Voyager data.

    Ibex ribbon
    The IBEX ribbon is a relatively narrow strip of particles flying in towards the sun from outside the heliosphere. A new study corroborates the idea that particles from outside the heliosphere that form the IBEX ribbon actually originate at the sun – and reveals information about the distant interstellar magnetic field. Credits: SwRI

    “The new findings can be used to better understand how our space environment interacts with the interstellar environment beyond the heliopause,” said Eric Christian, IBEX program scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who was not involved in this study. “In turn, understanding that interaction could help explain the mystery of what causes the IBEX ribbon once and for all.”

    The Southwest Research Institute leads IBEX with teams of national and international partners. NASA Goddard manages the Explorers Program for the agency’s Heliophysics Division within the Science Mission Directorate in Washington.

    Related Link

    IBEX mission website
    Article: The Astrophysical Journal LettersLocal Interstellar Magnetic Field Determined From the Interstellar Boundary Explorer Ribbon

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard campus
    NASA/Goddard Campus

    NASA image

     
  • richardmitnick 9:29 pm on February 23, 2016 Permalink | Reply
    Tags: , , , NASA Goddard   

    From Goddard: “Advanced NASA-Developed Instrument Flies on Japan’s Hitomi” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    Feb. 23, 2016
    Lori Keesey
    NASA’s Goddard Space Flight Center

    Now that Japan’s Hitomi spacecraft is safely in orbit, a team of NASA scientists is now ready to begin gathering data about the high-energy universe with an advanced instrument that carries never-before-flown technologies.

    JAXA Hitomi ASTRO-H instruments
    Hitomi Instrumentation

    JAXA Hitomi telescope
    JAXA/Hitomi

    The mission, formerly known as Astro-H, launched February 17 from the Tanegashima Space Center aboard an H-IIA rocket. Hitomi is expected to significantly extend the studies initiated by JAXA’s Suzaku mission that officially ended in September 2015.

    JAXA Suzaku satellite
    JAXA/Suzaku

    NASA’s more capable Soft X-ray Spectrometer (SXS), developed by a team of scientists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is one of the mission’s four scientific instruments.

    NASA  Soft X-ray Spectrometer on JAXA Hitomi
    An instrument scientist inspects the Soft X-ray Spectrometer before its final closing. The SXS is one of four payloads flying on the Japanese-led Hitomi mission launching in February. Credits: NASA

    With its unprecedented capabilities, SXS will enable a wide variety of breakthrough investigations — namely, studying the motion of matter approaching the event horizons of black holes, measuring the abundances of elements in the universe, and determining the evolution of galaxies and galaxy clusters throughout cosmic time. Hitomi carries three other powerful instruments: the Soft X-Ray Imager, the Hard X-Ray Imager, and the Soft Gamma Detector. [See above graphic]

    While similar in many respects to the X-ray Spectrometer that flew on Suzaku, which stopped operating shortly after launch due to a spacecraft design flaw, Hitomi’s SXS offers a number of significant improvements in the area of detector performance, cooling technologies, and collecting area. These advancements were made possible by NASA’s prior investment in these technologies, said NASA scientist Richard Kelley, who was named Goddard’s Innovator of the Year in 2008 based upon his work advancing SXS-related technologies, including the novel X-ray detection technique called microcalorimetry.

    In microcalorimetry, X-ray photons striking the detector’s absorbers are converted to heat, the magnitude of which is directly proportional to the X-ray’s energy. Analysis of the distribution of the X-ray photon’s energies, or spectrum, reveals much about the physical properties of the source emitting the radiation.

    Due to the inherently small size of an individual microcalorimeter detector, an array of detectors is constructed to collect as many X-ray photons as possible. To precisely determine the incoming X-ray photons, the detector package is cooled by a miniature refrigerator and the assembly is placed inside a dewar filled with liquid helium cooled to about one-tenth of a degree above absolute zero. The instrument is then placed at the focus of a large X-ray telescope to further augment the number of X-ray photons detected.

    Below are more details on the specific NASA contributions to the SXS instrument.

    SXS Microcalorimeter Array

    Chief among the instrument’s improvements over its Suzaku predecessor is the SXS’s 36-pixel microcalorimeter array. Using improved absorbers, which help convert the individual X-rays into heat, it offers better energy resolution and operates at an even lower temperature, Kelley said.

    Onboard Refrigerator

    Just as important as SXS’s 36 microcalorimeters, however, is its cooling technology. When NASA selected Kelley and his team to build the Hitomi instrument, the agency baselined a two-stage adiabatic demagnetization refrigerator (ADR), a mechanical cooling system that operates much like a household refrigerator, but using liquid helium as its coolant.

    However, in the wake of the premature loss of the XRS due to the unforeseen coolant boil-off that occurred on Suzaku, on Hitomi, NASA wanted to make sure the dewar remained at a super-cold temperature even if it ran out of coolant, Kelley said. Consequently, the team added a third stage to the cooling system.

    In addition to being more efficient, the three-stage ADR runs longer before needing a recharge. Better yet, however, the never-before-flown three-stage ADR will cool the dewar with or without the system’s liquid helium coolant.

    “On Suzaku, once the coolant was gone, so was the instrument,” Kelley said. “NASA wanted to push beyond that and provide more capability. In other words, redundancy was the driving requirement for flying the three-stage ADR.”

    X-ray Filters and Mirror Segments

    In addition to the improvements incorporated in the detector array and associated cooling approach, enhancements were made in two other components of the instrument.

    Kelley noted that the SXS is equipped with stronger filters needed to block longer-wavelength radiation from reaching the detector. The filters are situated in front of an aperture that allows X-rays to enter the dewar and is intricately built into the dewar. Should ice build up on the filters, mission operators can defrost them, much like how drivers can eliminate frost and ice on vehicle rear windows.

    The instrument’s mirror assembly also benefited from past research and development. The mirrors are so good, in fact, that Kelley’s team produced two: one for the SXS and another for Hitomi’s Soft X-ray Imager, provided by JAXA.

    Consisting of 1,624 curved mirror segments, all nested inside a canister, the assembly is lightweight and relatively inexpensive. The Goddard team made the mirror segments from commercial aluminum and then coated each with a special epoxy and a thin gold film to assure that each was smooth enough to efficiently reflect X-rays onto the microcalorimeter array. In addition, refinements made to the individual mirror segments’ shape (or “figure”) resulted in a mirror with considerably better focusing properties, which, in turn, contributed to the instrument’s overall detection capability.

    “Our technological innovation is a higher-spectral resolution instrument, with greater collecting area — all built with a relatively small team working very closely with a team of scientists and engineers in Japan,” Kelley said.

    For more Goddard technology news, go to https://gsfctechnology.gsfc.nasa.gov/newsletter/Current.pdf

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
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