Cassini Radar Sees Bright Flow-Like Feature on Titan
A strikingly bright feature that is consistent with an active
geology has been seen in one of Cassini's first radar images of
Saturn's moon Titan. There are many possibilities for what it is
but one of the leading candidates is that it may be a
'cryovolcanic' flow or 'ice volcano'.
Image above: This synthetic aperture radar image of the surface of Saturn's moon Titan was acquired on Oct. 26, 2004, when the Cassini spacecraft flew approximately 2,500 kilometers (1,553 miles) above the surface and acquired radar data for the first time.
Image credit: NASA/JPL.
+ Click for full caption
"It may be something that flowed," said Cassini radar team member
Dr. Ralph Lorenz of the University of Arizona, Tucson. "Or it
could be something carved by erosion. It's too early to say.
"But it looks very much like it's something that oozed across the
surface. It may be some sort of cryovolcanic flow, an analog to
volcanism on Earth that is not molten rock but, at Titan's very
cold temperatures, molten ice."
A radar image is available at http://saturn.jpl.nasa.gov
Cassini's radar mapped about one percent of Titan's surface
during the spacecraft's first close Titan flyby on Oct. 26. The
radar survey covered a strip 120 kilometers (75 miles) wide and
1,960 kilometers (1,200 miles) long in Titan's northern
Cassini was flying about 2,494 (1,550 miles) above Titan's
surface, with its radar centered at about 45 degrees north, 30
degrees west, when it mapped the 230-square-kilometer (90-square-
mile) area shown in the new radar image. The Cassini radar team
presented the image yesterday at the 36th annual meeting of the
American Astronomical Society’s Division for Planetary Sciences
in Louisville, Ky.
The radar instrument on board Cassini works by bouncing radio
signals off Titan's surface and timing their return. The more
signal reflected back to the spacecraft, the brighter the imaged
area. Turning radio signals into radar images is time consuming
because so many numerical calculations must be made. "There's no
such thing as a 'raw' radar image," said Lorenz.
Just two days after the Oct. 26 flyby, Cassini scientists knew
that Titan is not a crater-pocked dead world, but a much more
interesting place. Titan's surface is young. It might have been
altered by ongoing dynamic geologic processes that cover and
obscure old impact craters. Lorenz, and Cassini interdisciplinary
scientist Dr. Jonathan Lunine also of the University of Arizona,
and other Cassini scientists, agree in this interpretation.
Given this newest image, Lunine said, "Cassini's radar has
provided the first evidence for possible young cryovolcanism on
Titan's surface. Now our challenge is to find out what is
flowing, how it works, and the implications for Titan's
More information on the Cassini-Huygens mission is available at
The Cassini-Huygens mission is a cooperative project of NASA, the
European Space Agency and the Italian Space Agency. The Jet
Propulsion Laboratory, a division of the California Institute of
Technology in Pasadena, manages the Cassini-Huygens mission for
NASA's Science Mission Directorate, Washington, D.C. The Cassini
orbiter and its two onboard cameras were designed, developed and
assembled at JPL. The radar instrument team is based at JPL
working with team members from the United States and several
Carolina Martinez (818) 354-9382
NASA's Jet Propulsion Laboratory
Lori Stiles (520) 621-5585
University of Arizona, Tucson