Barrett's esophagus refers to an abnormal change in the cells of the lower portion of the esophagus. It is characterized by the replacement of the normal stratified squamous epithelium lining of the esophagus by simple columnar epithelium with goblet cells (which are usually found lower in the gastrointestinal tract).
U.S. Space Camp is a camp and related programs owned and operated by the Alabama Space Science Exhibit Commission's U.S. Space & Rocket Center in Huntsville, Alabama.
Special events take place regularly at the Kennedy Space Center. As a working shuttle launch site, the center is often an ideal place for visitors to see a shuttle or rocket launch up close. Astronauts also visit the space center frequently for special lectures or programs.