It has not been possible to captures images of the entire sunlit side of Earth at once since Apollo 17 astronauts captured the iconic Blue Marble photograph in 1972.

But this week NASA has, with a bit of help from the Deep Space Climate Observatory (DSCOVR), produced one.

Since 1972, complete images of our planet have mostly been mosaics stitched together with image processing software, not a single view of Earth taken at one moment in time.

On February 11th this year, DSCOVR was finally lofted into space by a SpaceX Falcon 9 rocket. After journey of about 1.6 million kilometers (1 million miles) to the L1 Lagrange Point, the satellite and its Earth Polychromatic Imaging Camera (EPIC) has returned its first view of the entire sunlit side of Earth. 

At L1—four times farther than the orbit of the Moon, the gravitational pull of the Sun and Earth cancel out, providing a stable orbit and a continuous view of Earth. 

The image was made by combining information from EPIC’s red, green, and blue bands. (Bands are narrow regions of the electro magnetic spectrum to which a remote sensing instrument responds. When EPIC collects data, it takes a series of 10 images at different bands—from ultraviolet to near infrared.)

This first public image shows the effects of sunlight scattered by air molecules, giving the disk a characteristic bluish tint. The EPIC team is developing data processing techniques that will emphasize land features and remove this atmospheric effect. 

Once the instrument begins regular data acquisition, new images will be available every day, 12 to 36 hours after they are acquired by EPIC. These images will be posted to a dedicated web page by autumn 2015. 

Data from EPIC will be used to measure ozone and aerosol levels in Earth’s atmosphere, as well as cloud height, vegetation properties, and the ultraviolet reflectivity of Earth. NASA will use this data for a number of Earth science applications, including dust and volcanic ash maps of the entire planet.

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