NASA recently published an infrared image of Titan, Saturn’s largest moon. The image, revealing interesting terrain on Titan, was acquired by the Saturn-orbiting Cassini spacecraft. Titan (5,150 km across) is the second largest moon in the Solar System, after Jupiter’s moon Ganymede (5,250 km across). It is also larger than Mercury (4,880 km across), the smallest planet, and nearly twice more massive than Earth’s Moon (3,476 km across).
Titan is a unique moon, since it has a thick atmosphere, whose surface pressure is 50% greater than that of Earth. Titan’s nitrogen-dominated atmosphere has clouds and hazes that obscure the moon’s surface. Therefore, scientists apply infrared and radar devices, to peer through Titan’s atmosphere. Interestingly, Cassini’s radar images revealed strong evidence that Titan has large lakes, filled with organic liquids.
Cassini’s image shows Titan’s prominent dark terrain, Shangri-La, which is located east of the area where the European space probe Huygens landed in January 2005. Saturn’s magnificent rings are visible in the background, as thin stripes. Cassini was orbiting just above the plane of the rings, approximately 1.4 million km from Titan, at the time the image was taken. The image was obtained with Cassini’s narrow-angle camera, on 9 August 2011, using an infrared filter.
Titan orbits Saturn every 15.9 days, at an average distance of approximately 1,220,000 km. Its name, meaning giant, comes from Greek mythology.
References
NASA’s Photojournal
http://photojournal.jpl.nasa.gov/
Wikipedia
Further Reading
The Cassini Mission Homepage
http://saturn.jpl.nasa.gov/