I never get tired of space pics (latest from Cassini)

[n2doc]

Surprise Hidden in Titan's Smog: Cirrus-Like Clouds

Titan's northern half, where it's early spring, appears slightly darker than the southern half, where it's early fall, in this image taken on March 22, 2010. Like Earth, Titan has four distinct seasons, each of which lasts about seven of Earth's years. Credit: NASA/JPL/Space Science Institute
› Larger image Every day is a bad-air day on Saturn's largest moon, Titan. Blanketed by haze far worse than any smog belched out in Los Angeles, Beijing or even Sherlock Holmes's London, the moon looks like a dirty orange ball. Described once as crude oil without the sulfur, the haze is made of tiny droplets of hydrocarbons with other, more noxious chemicals mixed in. Gunk.

Icky as it may sound, Titan is really the rarest of gems: the only moon in our solar system with an atmosphere worthy of a planet. This atmosphere comes complete with lightning, drizzle and occasionally a big, summer-downpour style of cloud made of methane or ethane -- hydrocarbons that are best known for their role in natural gas.

Now, thin, wispy clouds of ice particles, similar to Earth's cirrus clouds, are being reported by Carrie Anderson and Robert Samuelson at NASA's Goddard Space Flight Center in Greenbelt, Md. The findings, published February 1 in Icarus, were made using the Composite Infrared Spectrometer (CIRS) on NASA's Cassini spacecraft.

Unlike Titan's brownish haze, the ice clouds have the pearly white appearance of freshly fallen snow. Their existence is the latest clue to the workings of Titan's intriguing atmosphere and its one-way "cycle" that delivers hydrocarbons and other organic compounds to the ground as precipitation. Those compounds don't evaporate to replenish the atmosphere, but somehow the supply has not run out (yet?).
http://www.nasa.gov/mission_pages/cassini/whycassini/titan-clouds.html



Wisps Before Craters
January 31, 2011 Full-Res: PIA12751

Saturn's ''wispy'' moon Dione lies in front of the cratered surface of the moon Tethys, as seen by the Cassini spacecraft.
Dione is closest to the spacecraft here. At the top of the image, the bright ''wispy'' fractures are visible on Dione (1,123 kilometers, or 698 miles, across). See Dione's Icy Wisps and Highest Resolution View of Dione to learn more. Beyond wispy Dione, the large crater Penelope can be seen near the equator of Tethys (1,062 kilometers, or 660 miles, across). See Penelope Crater for a closer view of Penelope.
Lit terrain seen here is on the trailing hemispheres of the two moons. The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on Dec. 6, 2010.
The view was obtained at a distance of approximately 2.1 million kilometers (1.3 million miles) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 75 degrees.
The view was obtained at a distance of approximately 2.2 million kilometers (1.4 million miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 75 degrees. Scale in the original image was 12 kilometers (7 miles) per pixel on Dione and 13 kilometers (8 miles) per pixel on Tethys. The image was contrast enhanced and magnified by a factor of two to enhance the visibility of surface features.
http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=4237



Enceladus Jets (raw image)
February 1, 2011
http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=4240


Cassini Jupiter Portrait

This true color mosaic of Jupiter was constructed from images taken by the narrow angle camera onboard NASA's Cassini spacecraft on December 29, 2000, during its closest approach to the giant planet at a distance of approximately 10 million kilometers (6.2 million miles).

It is the most detailed global color portrait of Jupiter ever produced; the smallest visible features are approximately 60 kilometers (37 miles) across. The mosaic is composed of 27 images: nine images were required to cover the entire planet in a tic-tac-toe pattern, and each of those locations was imaged in red, green, and blue to provide true color. Although Cassini's camera can see more colors than humans can, Jupiter's colors in this new view look very close to the way the human eye would see them.

Everything visible on the planet is a cloud. The parallel reddish-brown and white bands, the white ovals, and the large Great Red Spot persist over many years despite the intense turbulence visible in the atmosphere. The most energetic features are the small, bright clouds to the left of the Great Red Spot and in similar locations in the northern half of the planet. These clouds grow and disappear over a few days and generate lightning. Streaks form as clouds are sheared apart by Jupiter's intense jet streams that run parallel to the colored bands. The prominent dark band in the northern half of the planet is the location of Jupiter's fastest jet stream, with eastward winds of 480 kilometers (300 miles) per hour. Jupiter's diameter is eleven times that of Earth, so the smallest storms on this mosaic are comparable in size to the largest hurricanes on Earth.

Unlike Earth, where only water condenses to form clouds, Jupiter's clouds are made of ammonia, hydrogen sulfide, and water. The updrafts and downdrafts bring different mixtures of these substances up from below, leading to clouds at different heights. The brown and orange colors may be due to trace chemicals dredged up from deeper levels of the atmosphere, or they may be byproducts of chemical reactions driven by ultraviolet light from the Sun. Bluish areas, such as the small features just north and south of the equator, are areas of reduced cloud cover, where one can see deeper.
http://www.nasa.gov/mission_pages/cassini/multimedia/pia04866.html

[ZombieHorde]

1. Awesome. nt

[Loki]

2. Beautiful.

[LongTomH]

3. Great Stuff! Thanks for posting them!

[AlecBGreen]

4. cool!

do you think life is possible on a place like Titan? Lots of hydrocarbons but sooooo cold.

[atomic-fly]

5. stunning...thanks for posting!

I love space exploration and wish we would fund more of it.