Study Finds Space Shuttle Exhaust Creates Night-shining Clouds

Exhaust from the main engines of NASA’s space shuttle, which is about 97 percent water vapor, can travel to the Arctic in Earth’s thermosphere, the highest part of the atmosphere, where it forms ice to create clouds that shine at night, according to a new study. The thermosphere is above 88 kilometers [55 miles] altitude. The clouds settle to around 82 kilometers [51 miles] altitude in the layer directly below, called the mesosphere. The stratosphere and the troposphere lie in that order below the mesosphere.

Health system unprepared for water terrorism

National public health experts reported today that front-line health care responders are not adequately prepared to identify and control major outbreaks of waterborne disease, including outbreaks resulting from acts of terrorism. The conclusions were reported at a conference convened by the American College of Preventive Medicine on waterborne disease and acts of water terrorism.