Earth from Odyssey
May 02, 2001
The above image pair was taken late last week by the Mars Odyssey spacecraft on its way to the red planet. It was launched on April 7. The image at left shows the crescent Earth in visible light, and the right-hand image is a thermal infrared image of the Earth taken at the same time with the Thermal Emission Imaging System (THEMIS). This system will eventually map the Martian surface to determine what minerals are present. In this case, its looking back at the Earth and revealing its temperature (red is hot and blue is cold). THEMIS observed a temperature in the "outback" of Australia on this night (the Earth is facing away from the Sun here) of 9 degrees C, which is very close to a ground-based measure of 10 degrees C (50 degrees F). For Antarctica, the estimated temperature (from THEMIS) is - 50 degrees C near the Russian Vostok Station (actual temperature about - 63 degrees C).