This map of the surface of Saturn's moon Tethys illustrates the regions that will be imaged by Cassini during the spacecraft's close flyby of the moon on Sept. 24, 2005. At closest approach, the spacecraft is expected to pass approximately 1,500 kilometers (930 miles) above the moon's surface. Tethys is 1,071 kilometers (665 miles) across.

This map of the surface of Saturn's moon Tethys illustrates the regions that will be imaged by Cassini during the spacecraft's close flyby of the moon on Sept. 24, 2005. At closest approach, the spacecraft is expected to pass approximately 1,500 kilometers (930 miles) above the moon's surface. Tethys is 1,071 kilometers (665 miles) across.

This week Cassini will play a doubleheader with two flybys of Saturn's moon's Tethys (Sept. 24) and Hyperion (Sept. 26). Cassini will be eye-to-eye with Tethys' giant Odysseus impact-crater. Cassini's close brush with the chaotic, tumbling Hyperion might tell us whether it is a rubble pile.

Scientists also hope to be able to shed more light on the following:

  • The origin of the huge canyon-like feature named Ithaca Chasma on Tethys is not completely understood, but it might be related to the impact that created Odysseus.
  • Hyperion's elliptical orbit and irregular shape influence its chaotic tumbling, which may have started after a giant impact with another body.