January 12, 2009
This captivating photo of Grand Geyser in the Upper Geyser Basin of Yellowstone National Park, Wyoming was taken on the afternoon of June 24, 2008. Seen on the right, Grand Geyser is erupting here with a simultaneous eruption of Vent Geyser (left). These are both fountain-type geysers. Geothermally heated water from Grand Geyser is propelled to heights of 200 ft (61 m). The eruption may last up to 12 minutes. This impressive geyser is considered the tallest, predictable geyser in the world, erupting about every 12 hours.
Photo details: Canon EOS Digital rebel xTi camera; 1/1,250 sec exposure time; f/8, 17 mm lens focal length, Exposure Program Manual; ISO speed rating of 100.