October 22, 2005-Galapagos Islands
The Sierra Negra Volcano
http://www.earthobservatory.nasa.gov/NaturalHazards/shownh.php3?img_id=13253
Earth Observatory
http://www.earthobservatory.nasa.gov/NaturalHazards/shownh.php3?img_id=13282
Why does Yellowstone Park need monitoring?
I'll let these sites answer that question.
NationalGeographic.com
Yellowstone Volcano: Is "The Beast" Building to a Violent Tantrum?
http://www.news.nationalgeographic.com/news/2001/08/0828_wireyellowstone.html
USGS and the National Park Service-Our Volcanic Public Lands
USGS Fact Sheet 2005
http://www.pubs.usgs.gov/fs/2005/3024
USGS Yellowstone Volcano Observatory
http://www.volcanoes.usgs.gov/yvo/index.html
NASA's Earth Observatory Natural Hazards
http://www.earthobservatory.nasa.gov/
US Geological Survey