NASA, along with Japan, has made all of Earth’s imagery available online for free on April 1. The stunning Earth photos were taken from the Japanese remote sensing instrument operating aboard the space agency’s Terra spacecraft. The instrument called Advanced Spaceborne Thermal Emission and Reflection Radiometer or ASTER has been gathering data about Earth’s changing surface since 1999, resulting in more than 2.95 million images.

These topographic data have been available online for free before but users had to pay Japan’s Ministry of Economy, Trade and Industry to access other ASTER data. Now, everyone can finally look at scenes such as the volcanic eruption in Iceland, wildfires in California, the consequences of flooding in Pakistan, and land changes in Oklahoma, just to name a few.

These data are part of NASA’s goal to increase our understanding of Earth, including analysing environment deterioration, monitoring potentially active volcanoes, observing coral reef destruction, determining crop stress, cloud changes and evaluating wetlands.


Eruption of Nicaragua’s Momotombo volcano. Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

ASTER is used to create detailed maps of elevation, reflectance and land surface temperature with its near-infrared spectral band and downward and backward-viewing telescopes. The data covers 99 percent of Earth’s landmass and span from 83 degrees north latitude to 83 degrees south. A single downward-looking scene covers an area that measures 60-by-60-kilometres.


Pine Island Glacier.

The data are processed into products using algorithms created at the Jet Propulsion Laboratory and the National Institute of Advanced Industrial Science and Technology (AIST) in Japan. A team of scientists from the US and Japan validates and calibrates the instrument and data products.


Poyang Lake. Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

NASA states that ASTER will still operate and continue to monitor the Earth aboard Terra. The scientists also aim to provide users with more data in the future.


Beihai is a city in the south of Guangxi, People’s republic of China. It is a seaport on the north shore of the Gulf of Tonkin. Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

“We anticipate a dramatic increase in the number of users of our data, with new and exciting results to come,” says Michael Abrams, science team leader of ASTER at NASA’s Jet Propulsion Laboratory in Pasadena, California.