|
Lofn is a large relatively young impact crater on Jupiter's Galilean satellite Callisto. It was identified in 1997 and named after the goddess of marriage in Norse mythology. Located near the south pole of this moon, Lofn is classified as a flat floored or anomalous dome impact crater. It is superimposed on Adlinda multilayer structure obscuring about 30% of it. Another multi-ring structure—Heimdall is found to the south-west of Lofn. Geologically Lofn is divided into a number of zones including the flat central floor zone, ring of massifs around it and the outer rings of bright and dark impact ejecta. Lofn was probably formed by an oblique impactor coming from the north-west. The relative shallowness of it is explained by either fragmentation of the impactor prior to the contact with the surface or by the post impact relaxation of Callisto's ductile crust. ==Discovery and location== Lofn is one of the largest impact craters on Jupiter's moon Callisto. It is located in the southern hemisphere near the moon's south pole. The latitude and longitude of its center are 56°S and 23°W, respectively. The diameter of Lofn is about 180 km. Lofn was first observed as a large high albedo circular feature (palimpsest) on low resolution images taken by Voyager spacecraft in 1979–1980.〔 It was misidentified as a multi-ring structure and called Adlinda. Later in 1997 Galileo spacecraft took a number of high resolution images during its G2 and G8 orbits revealing a large flat-floored crater instead of multi-ring structure. It was determined that Adlinada is actually located slightly to the north-west of Lofn, which partially obscures it. Another multi-ring structure—Heimdall is situated to the south-east of Lofn.〔 Lofn was named after the goddess of marriage in Norse mythology. 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「Lofn (crater)」の詳細全文を読む スポンサード リンク
|