NASA’s Goddard releases rare image of Earth

NASA’s Goddard releases rare image of Earth


It’s another stunning image of Earth.

NASA’s Goddard Space Flight Center has released another spectacular image of Earth, the second such photo to come out of the U.S. space agency this week. Responding to popular demand, the U.S. space agency released its second 2012 version of the famous “Blue Marble” image earlier this week, focusing on Africa and Asia.

By using a planet-pointing satellite, Suomi NPP, the space agency created an extremely high-resolution photograph of our watery world. The first image, released earlier this week, shows North America, Central America and the Caribbean.

The latest image is focused on the East, showing Africa, Saudi Arabia and India.

Compiled by NASA Goddard scientist Norman Kuring, the latest image has the perspective of a viewer looking down from 7,918 miles above the Earth’s surface from a viewpoint of 10 degrees South by 45 degrees East. The four vertical lines of ‘haze’ visible in the image shows the reflection of sunlight off the ocean, or ‘glint,’ that VIIRS captured as it orbited the globe.

The original ‘Blue Marble’ image is a photograph taken by the Apollo 17 astronauts as they traveled toward the moon. It was taken at a distance of about 28,000 miles. NASA launched the $1.5 billion Suomi NPP satellite in October 2011 on a mission to help monitor Earth’s weather and natural disasters.

As for actually creating the image, NASA noted that the project took a number of months. The land and coastal ocean portions of the images are based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the sensor’s view of the surface on any single day, according to the space agency.

Two different types of ocean data were used in these images: shallow water true color data, and global ocean color data. The topographic shading is based on an elevation dataset compiled by the U.S. Geological Survey’s EROS Data Center. MODIS observations of polar sea ice were combined with observations of Antarctica made by the National Oceanic and Atmospheric Administration’s (NOAA) AVHRR sensor—the Advanced Very High Resolution Radiometer.

The cloud image is a composite of two days of imagery collected in visible light wavelengths and a third day of thermal infra-red imagery over the poles. Global city lights, derived from nine months of observations from the Defense Meteorological Satellite Program, are superimposed on a darkened land surface map.