|
Sedan Crater is the result of the Sedan nuclear test and is located within the Nevada Test Site, just southwest of Groom Lake, Nevada (Area 51). The crater was listed on the National Register of Historic Places on March 21, 1994.〔 The crater is a man-made object that can be seen from earth orbit with the unaided eye. The crater is the result of the displacement of of earth.〔 Over 10,000 visitors per year〔(Nevada Test Site History. ''Sedan Crater'' )〕 visit the crater through free monthly tours offered by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office.〔 Its closest Soviet counterpart is the slightly wider Chagan crater which filled in to create Lake Chagan. == History and description == The crater was created on July 6, 1962 by a thermonuclear explosion.〔〔 The device was buried 〔 below the desert floor in Area 10 of Yucca Flat and was the largest cratering shot in the Plowshare Program. The explosion created fallout that affected more US residents than any other nuclear test, exposing more than 13 million people to radiation and marked the end of the program.〔(All Around Nevada with a 360 image )〕 Within 7 months of the excavation, the bottom of the crater could be safely walked upon with no protective clothing and photographs were taken. Because the craters at the Nevada Test Site (NTS) have features similar to the topography of Moon craters 11 of the 12 American astronauts who walked on the moon trained in Nevada before their missions. Russian thistle, also known as tumbleweed, is the primary plant species along with some grasses. Analysis in 1993 observed that the original perennial shrubs once living there had shown no recovery.〔(Sedan Crater at Nevada Online )〕 Satellite imagery such as that available in Google Earth, however, shows considerable growth on the ejecta blanket outside the crater rim. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Sedan Crater」の詳細全文を読む スポンサード リンク
|