Titan, Saturn’s largest moon
The picture, acquired infrared by the Cassini spacecraft, shows a large storm, blowing in the atmosphere of Titan, Saturn’s largest moon. The storm is visible as a whitish arrow-shaped cloud, near the left limb of Titan.
Credit: NASA/JPL/Space Science Institute
 
 

NASA recently published a wonderful image of Titan, Saturn’s largest moon. The picture was acquired in infrared light, by the Saturn-orbiting Cassini spacecraft, on 27 September 2010, at a distance of approximately 1.3 million km from Titan. It shows a huge, arrow-shaped storm, evolving in Titan’s thick, hazy atmosphere.

The 1500-km-wide storm blows across the equatorial region of Titan (5,150 km across). The storm gave rise to dark, likely wet, areas on the surface of Titan, recorded in later Cassini images.

Titan is the second largest moon in the Solar System, after Ganymede (5,250 km across), Jupiter’s giant satellite. Titan is 1.5 times larger in size, and nearly twice more massive than Earth’s Moon (3,476 km across). It is even larger than Mercury (4,880 km across), the smallest planet, and is also the only known moon with a substantial atmosphere, whose surface pressure is 50% greater than that of Earth.

Titan’s atmosphere is composed mostly of nitrogen (about 95%), and methane (about 4.9%), with small amounts of other gases, such as ethane and argon. Thick smog in Titan’s atmosphere almost totally obscures the surface of the moon. Scientists rather apply infrared and radar techniques, which can penetrate Titan’s nearly opaque atmosphere, to image the surface features of Titan.

Titan orbits Saturn every 15.9 days, at an average distance of about 1,220,000 km. Like our Moon (3,476 km across), Titan keeps the same side turned to its planet. The name Titan comes from Greek mythology.

References

NASA
www.nasa.gov/
Cassini Mission Homepage
http://saturn.jpl.nasa.gov/
Titan's Arrow-Shaped Storm
http://photojournal.jpl.nasa.gov/catalog/PIA12817
Wikipedia


Aymen Mohamed Ibrahem
Senior Astronomy Specialist