描述Callisto Asgard PIA00562.jpg |
Ελληνικά: Κρατήρες στην επιφάνεια της Καλλιστούς, δεύτερου μεγαλύτερου δορυφόρου του πλανήτη Δία. Στο κέντρο ο κρατήρας Άσγκαρντ, τον οποίο περιβάλλουν δακτύλιοι που εκτείνονται σε διάμετρο 1.7000 χιλιομέτρων. Παραδίπλα, νεότεροι κρατήρες που έχουν ανασκάψει τον πάγο από τον οποίο αποτελείται εξωτερικά η Καλλιστώ. Φωτογραφία από την αποστολή Galileo.
English: Impact craters on Callisto, second largest moon of Jupiter, as imaged by Galileo spacecraft in 1997. Asgard crater in the middle, surrounded by rings extemdimg outwars in a diameter of 1,700 km. Newer impacts have dug up ice, which comprises Callisto's outer crust.
Original caption
Low-resolution color data were combined with a higher resolution mosaic to produce this infrared composite image of a pair of ancient multi-ringed impact basins on Jupiter's moon, Callisto. The region imaged is on the leading hemisphere of Callisto near 26 degrees north, 142 degrees west, and is almost 1,400 kilometers (860 miles) across. North is toward the top of the picture and the Sun illuminates the surface from the east. Dominating the scene is the impact structure, Asgard, centered on the smooth, bright region near the middle of the picture and surrounded by concentric rings up to 1,700 kilometers (about 1,050 miles) in diameter. A second ringed structure with a diameter of about 500 kilometers (310 miles) can be seen to the north of Asgard, partially obscured by the more recent, bright-rayed crater, Burr. The icy materials excavated by the younger craters contrast sharply with the darker and redder coatings on older surfaces of Callisto.
Launched in October 1989, Galileo entered orbit around Jupiter on Dec. 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC. |