Thursday, April 22, was the 50 th anniversary of Earth Day. So it’s a great time to have a look at our beautiful world through the eyes of NASA’s Terra satellite, which was introduced in December 1999 to keep track of the environment and the impacts of climate change. These images are taken with the ASTER instrument, which stands for Advanced Spaceborne Thermal Emission and Reflection Radiometer. It gathers data in a variety of wavelengths to parse out fine distinctions in mineralogy, water temperature level, and heat activity on earth’s surface. By observing the ground with infrared instruments, researchers can identify heat modifications in the surface, like the melting of permafrost or heat emissions in the environment. The outcome is high-resolution images of the surface area of the Earth, clouds, ice, and water in nearly alien rainbow colors.
