NASA Cassini Spacecraft Snaps Saturn Methane Image
The Cassini narrow angle camera took this image of Saturn on Feb. 16,
2004, from a distance of 66.1 million kilometers (41.1 million
miles) in a special filter which reveals clouds and haze high in
the atmosphere.
The image scale is 397 kilometers (247 miles) per pixel. The MT2
spectral filter samples a near-infrared region of the electromagnetic
spectrum where methane gas absorbs light at a wavelength of 727
nanometers. In the image, methane gas is uniformly mixed with
hydrogen, the main gas in Saturn’s atmosphere. Dark locales are
places of strong methane absorption, relatively free of high clouds;
the bright areas are places with high, thick clouds which shield the
methane below.
Image details reveal a high, thick equatorial cloud and a relatively
deep or thin haze encircling the pole, as well as several distinct
latitude bands with different cloud height attributes. It also shows
a high atmospheric disturbance, just south of the equator, which has
persisted throughout the 1990s in images returned by NASA?s Hubble
Space Telescope.
Four of Saturn’s moons are visible (clockwise from above right):
Enceladus (499 kilometers, or 310 miles across); Mimas (396
kilometers, or 245 miles across); Tethys (1,060 kilometers, or
659 miles across); and Rhea (1,528 kilometers, or 949 miles across).
The imaging team enhanced the brightness of Mimas and Enceladus by a
factor of three.
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 mission for NASA’s
Office of Space Science, Washington, D.C. The imaging team is based
at the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission visit,
and the Cassini imaging team home page,
Image Credit: NASA/JPL/Space Science Institute
Full-Res: PIA05381 http://photojournal.jpl.nasa.gov/catalog/PIA05381
