The radiotelescope established in Аресибо, — now, the world's largest (from using one aperture). The telescope is used for researches in the field of radio astronomy, physics of an atmosphere and radar-tracking supervision of objects of Solar system. Astronomical observatory Аресибо is located in Пуэрто Рико, in 15 km from Аресибо, at height of 497 m above sea level. Researches are spent Корнельским by university to cooperations with National scientific fund (USA). The observatory is also the National center of Astronomy and the Ionosphere of the USA.