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This image shows the dusty disk of planetary material surrounding the young star HD 141569, located 380 light-years away from Earth. It was taken using the vortex coronagraph on the W.M. Keck Observatory. The vortex suppressed light from the star in the center, revealing light from the innermost ring of planetary material around the star (blue).  The disk around the star, made of olivine particles, extends from 23 to 70 astronomical units from the star. By comparison, Uranus is over 19 astronomical units from our sun, and Neptune about 30 astronomical units. One astronomical unit is the distance between Earth and our sun.  http://photojournal.jpl.nasa.gov/catalog/PIA21090
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Coronal mass ejections were popping out from the Sun at a pace of two per day on average (Apr. 18-23, 2013). We counted ten CMEs for the five days, but some of the eruptions were complex and difficult to differentiate from one another. Almost all of them blew particles out to the left, most of them probably originating from the same active region.  These were taken by the STEREO (Ahead) spacecraft?s coronagraph, in which the black disk blocks the Sun (represented by the white circle) so that we can observe the fainter features beyond it.  Credit: NASA/Goddard/STEREO  <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b>  <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.  <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b>  <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b>  <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>
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Completed: 07-16-2009  Straddling the equator approximately 1000 kilometers to the west of the South American mainland, the Galapagos Islands lie within the heart of the equatorial current system. Rising from the sea floor, the volcanic islands of the Galapagos are set on top of a large submarine platform. The main portion of the Galapagos platform is relatively flat and less than 1000 meters in depth. The steepest slopes are found along the western and southern flanks of the platform with a gradual slope towards the east. The interactions of the Galapagos and the oceanic currents create vastly different environmental regimes which not only isolates one part of the Archipelago from the other but allows penguins to live along the equator on the western part of the Archipelago and tropical corals around the islands to the north. The islands are relatively new in geologic terms with the youngest islands in the west still exhibiting periodic eruptions from their massive volcanic craters.   Please give credit for this item to: NASA/Goddard Space Flight Center, The SeaWiFS Project and GeoEye, Scientific Visualization Studio. NOTE: All SeaWiFS images and data presented on this web site are for research and educational use only. All commercial use of SeaWiFS data must be coordinated with GeoEye (http://www.geoeye.com).  To download this video go to:  <a href="http://svs.gsfc.nasa.gov/goto?3628" rel="nofollow">svs.gsfc.nasa.gov/goto?3628</a>  <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b>  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.
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A beautiful prominence eruption shot off the east limb (left side) of the sun on Monday, April 16, 2012. Such eruptions are often associated with solar flares, and in this case an M1 class (medium-sized) flare did occur at the same time, though it was not aimed toward Earth. This event, which is still in progress, was seen by NASA’s SDO satellite.  Credit: NASA/GSFC/SDO  <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b>  <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.  <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b>  <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b>  <b>Find us on <a href="http://instagrid.me/nasagoddard/?vm=grid" rel="nofollow">Instagram</a></b>
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This movie from NASA’s STEREO spacecraft's Heliospheric Imager shows Comet ISON, Mercury, Comet Encke and Earth over a five-day period from Nov. 20 to Nov. 25, 2013. The sun sits right of the field of view of this camera. Comet ISON, which will round the sun on Nov. 28, is what's known as a sungrazing comet, due to its close approach.  Foreshortening or the angle at which these images were obtained make Earth appear as if it is closer to the sun than Mercury. If you look closely you will also see a dimmer and smaller comet Encke near comet ISON.    A comet’s journey through the solar system is perilous and violent. A giant ejection of solar material from the sun could rip its tail off. Before it reaches Mars -- at some 230 million miles away from the sun -- the radiation of the sun begins to boil its water, the first step toward breaking apart. And, if it survives all this, the intense radiation and pressure as it flies near the surface of the sun could destroy it altogether.   Even if the comet does not survive, tracking its journey will help scientists understand what the comet is made of, how it reacts to its environment, and what this explains about the origins of the solar system. Closer to the sun, watching how the comet and its tail interact with the vast solar atmosphere can teach scientists more about the sun itself.   Image Credit: NASA/STEREO  <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b>   <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.   <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b>   <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b>   <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>
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Sungrazing comets are a special class of comets that come very close to the sun at their nearest approach, a point called perihelion. To be considered a sungrazer, a comet needs to get within about 850,000 miles from the sun at perihelion. Many come even closer, even to within a few thousand miles.  Being so close to the sun is very hard on comets for many reasons. They are subjected to a lot of solar radiation which boils off their water or other volatiles. The physical push of the radiation and the solar wind also helps form the tails. And as they get closer to the sun, the comets experience extremely strong tidal forces, or gravitational stress. In this hostile environment, many sungrazers do not survive their trip around the sun. Although they don't actually crash into the solar surface, the sun is able to destroy them anyway.  Many sungrazing comets follow a similar orbit, called the Kreutz Path, and collectively belong to a population called the Kreutz Group. In fact, close to 85% of the sungrazers seen by the SOHO satellite are on this orbital highway. Scientists think one extremely large sungrazing comet broke up hundreds, or even thousands, of years ago, and the current comets on the Kreutz Path are the leftover fragments of it. As clumps of remnants make their way back around the sun, we experience a sharp increase in sungrazing comets, which appears to be going on now. Comet Lovejoy, which reached perihelion on December 15, 2011 is the best known recent Kreutz-group sungrazer. And so far, it is the only one that NASA's solar-observing fleet has seen survive its trip around the sun.  Comet ISON, an upcoming sungrazer with a perihelion of 730,000 miles on November 28, 2013, is not on the Kreutz Path. In fact, ISON's orbit suggests that it may gain enough momentum to escape the solar system entirely, and never return. Before it does so, it will pass within about 40 million miles from Earth on December 26th.   More information on this topic available at: <a href="http://www.nasa.gov/content/goddard/timeline-of-comet-ison-s-dangerous-journey/" rel="nofollow">www.nasa.gov/content/goddard/timeline-of-comet-ison-s-dan...</a>  Credit: NASA's Goddard Space Flight Center  <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b>  <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.  <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b>  <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b>  <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>
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The night side of Earth twinkles with light, and the first thing to stand out is the cities. “Nothing tells us more about the spread of humans across the Earth than city lights,” asserts Chris Elvidge, a NOAA scientist who has studied them for 20 years.  This new global view and animation of Earth’s city lights is a composite assembled from data acquired by the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite. The data was acquired over nine days in April 2012 and thirteen days in October 2012. It took satellite 312 orbits and 2.5 terabytes of data to get a clear shot of every parcel of Earth’s land surface and islands. This new data was then mapped over existing Blue Marble imagery of Earth to provide a realistic view of the planet.  The nighttime view in visible light was made possible by the new “day-night band” of Suomi NPP’s Visible Infrared Imaging Radiometer Suite. VIIRS detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe dim signals such as city lights, auroras, wildfires, and reflected moonlight. This low-light sensor can distinguish night lights with ten to hundreds of times better light detection capability than scientists had before.  Named for satellite meteorology pioneer Verner Suomi, NPP flies over any given point on Earth&amp;rsquos surface twice each day at roughly 1:30 a.m. and 1:30 p.m. The polar-orbiting satellite flies 824 kilometers (512 miles) above the surface as it circles the planet 14 times a day. Data is sent once per orbit to a ground station in Svalbard, Norway, and continuously to local direct broadcast users around the world. The mission is managed by NASA with operational support from NOAA and its Joint Polar Satellite System, which manages the satellite's ground system.  NASA Earth Observatory image and animation by Robert Simmon, using Suomi NPP VIIRS data provided courtesy of Chris Elvidge (NOAA National Geophysical Data Center). Suomi NPP is the result of a partnership between NASA, NOAA, and the Department of Defense. Caption by Mike Carlowicz.  Instrument: Suomi NPP - VIIRS   Credit: <b><a href="http://www.earthobservatory.nasa.gov/" rel="nofollow"> NASA Earth Observatory</a></b>  <b>Click here to view all of the <a href="http://earthobservatory.nasa.gov/Features/NightLights/" rel="nofollow"> Earth at Night 2012 images </a></b>  <b>Click here to <a href="http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=79803" rel="nofollow"> read more </a> about this image </b>   <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b>  <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.  <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b>  <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b>  <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>
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