In 1972, NASA released the first complete photograph of the planet
Earth as it appears from outside the atmosphere. Its color and ornate appearance
quickly earned Earth the name “the Blue Marble,” and the image of the
planet against a background of open space went on to inspire millions of people
to care more about the environment and their animal and human neighbors.
Credit: NASA Goddard Space Flight Center. Image by Reto Stöckli; enhancements by Robert Simmon.
Imaging of the Earth from space did not end 40 years ago –
NASA continues to update the technology used to acquire these pictures. Recently,
the organization released new composite images of the planet, comprising visible
and infrared shots taken and stitched together over the course of months. NASA calls
the new photos the most detailed true-color images to date of the entire Earth.
Most of the images that make up the composite were obtained by
the Moderate Resolution Imaging Spectroradiometer (MODIS), an instrument aboard
the Terra satellite orbiting 700 miles above the planet. MODIS acquires images of
the entire Earth’s surface approximately every one to two days.
In addition to standard images of the land masses, shallow water
true color data and global ocean color data were used to generate oceanic images.
The National Oceanic and Atmospheric Administration’s Advanced Very High Resolution
Radiometer provided data for enhanced images of the polar sea ice, and the cloud
images were composed of two days of visible data collection and one day of infrared.
As improvements in resolution and multispectral technology continue
to arise, composite images such as these will include more information than ever
before available about the biology of the world. Perhaps, they will also inspire
us to be better care-takers of ourselves and the living world we inhabit.