Hello All!   
      
   Unprecedented New Images of Earth at Night Dec. 5, 2012:  Today at the   
   American Geophysical Union meeting in San Francisco, scientists unveiled an   
   unprecedented new look at our planet at night. A global composite image,   
   constructed using cloud-free night images from a new NASA and National Oceanic   
   and Atmospheric Administration (NOAA) satellite, shows the glow of natural and   
   human-built phenomena across Earth in greater detail than ever before.    
      
   "For all the reasons that we need to see Earth during the day, we also need to   
   see Earth at night," said Steve Miller, a researcher at NOAA's Colorado State   
   University Cooperative Institute for Research in the Atmosphere. "Unlike   
   humans, the Earth never sleeps."    
      
   This image of the continental United States at night is a composite assembled   
   from data acquired by the Suomi NPP satellite in April and October 2012. The   
   image was made possible by the satellite's "day-night band" of the Visible   
   Infrared Imaging Radiometer Suite (VIIRS), which detects light in a range of   
   wavelengths from green to near-infrared and uses filtering techniques to   
   observe dim signals such as city lights, gas flares, auroras, wildfires and   
   reflected moonlight. Credit: NASA Earth Observatory/NOAA NGDC >>   
   High-resolution download and more information   
      
   Many satellites are equipped to look at Earth during the day, when they can   
   observe our planet fully illuminated by the sun. With a new sensor aboard the   
   NASA-NOAA Suomi National Polar-orbiting Partnership (NPP) satellite launched   
   last year, scientists now can observe Earth's atmosphere and surface during   
   nighttime hours. The sensor, called "VIIRS" (short for Visible Infrared   
   Imaging Radiometer Suite), is sensitive enough to detect the light from a   
   single ship in the sea.    
      
   The day-night band of VIIRS observed Hurricane Sandy, illuminated by   
   moonlight, making landfall over New Jersey on the evening of Oct. 29. Night   
   images showed the widespread power outages that left millions in darkness in   
   the wake of the storm. With its night view, VIIRS is able to detect a more   
   complete view of storms and other weather conditions, such as fog, that are   
   difficult to discern with infrared, or thermal, sensors. Night is also when   
   many types of clouds begin to form.    
      
   "NOAA's National Weather Service is continuing to explore the use of the   
   day-night band," said Mitch Goldberg, program scientist for NOAA's Joint Polar   
   Satellite System. "The very high resolution from VIIRS data will take   
   forecasting weather events at night to a much higher level."    
      
      
   The Black Marble>>  Click to view more images and animations of the Earth at   
   nightUnlike a camera that captures a picture in one exposure, the day-night   
   band produces an image by repeatedly scanning a scene and resolving it as   
   millions of individual pixels. Then, the day-night band reviews the amount of   
   light in each pixel. If it is very bright, a low-gain mode prevents the pixel   
   from oversaturating. If the pixel is very dark, the signal is amplified.    
      
   "It's like having three simultaneous low-light cameras operating at once and   
   we pick the best of various cameras, depending on where we're looking in the   
   scene," Miller said. The instrument can capture images on nights with or   
   without moonlight, producing crisp views of Earth's atmosphere, land and ocean   
   surfaces.    
      
   "The night is nowhere as dark as we might think," Miller said. And with the   
   VIIRS day-night band helping scientists to tease out information from human   
   and natural sources of nighttime light, "we don't have to be in the dark   
   anymore, either."    
      
      
   Production editor: Dr. Tony Phillips | Credit: Science@NASA   
      
   More Information    
   > "Out of the Blue and Into the Black: New Views of the Earth at Night"    
   > (12.05.12)   
   > More views of Earth at night from NASA Earth Observatory   
   > NASA's Suomi NPP website   
   > Suomi NPP project website   
   > NOAA National Geophysical Data Center: Earth Observations Group, DMSP   
   > Earth "marble" imagery on Flickr   
   > NASA Earth Observatory: "Blue Marble: Next Generation" (2004)   
   > "Earth, Behind the Scenes": How VIIRS data from Suomi NPP becomes    
   > "marble" imagery (02.04.12)    
      
      
   Regards,   
      
   Roger    
   --- timEd/386 1.10.y2k+   
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