Mystery Photo

What in the world is it?

Don’t peek at the answer until you’ve given this a good try! Then, scroll down a bit and the truth will be revealed to you. What In the World Is It? This month’s mystery photo is a high-resolution image of part of Prometheus, an active volcano on Jupiter’s volcanic moon Io. The image was taken by NASA’s Galileo spacecraft on October 10, 1999, during its close flyby of Io. It shows a volcanic caldera, a large depression formed by the collapse of the ground after a volcanic eruption. Examples of calderas like this can be found in Hawaii. This image also shows dark lava flows and a strange, lumpy surface covered with sulfur-rich snow. The new image is shown over an earlier, color view. Credit: (NASA) Back