Iapetus Fly-by

Back


Scientists on the Cassini mission to Saturn are poring through hundreds of images returned from the 10th September 2007 flyby of Saturn's two-toned moon Iapetus. Pictures show a white hemisphere resembling snow, and the other as black as tar.

Images show a surface that is heavily cratered, along with the mountain ridge that runs along the moon's equator. Many of the close-up observations focused on studying the strange 20-kilometer high (12 mile) mountain ridge that gives the moon a walnut-shaped appearance.

This flyby was nearly 100 times closer to Iapetus than Cassini's 2004 flyby, bringing the spacecraft to about 1,640 kilometers (1,000 miles) from the surface. The moon's irregular walnut shape, the mountain ridge that lies almost directly on the equator and Iapetus' brightness contrast are among the key mysteries scientists are trying to solve.

The return of images and other data was delayed due to a galactic cosmic ray hit which put the spacecraft into a precautionary state called safe mode. This occurred after the spacecraft had placed all of the flyby data on its data recorders and during the first few minutes after it began sending the data home. The data flow resumed later that day and concluded on Wednesday. The spacecraft is operating normally and its instruments are expected to return to normal operations in a few days.

Cassini's multiple observations of Iapetus will help to characterize the chemical composition of the surface; look for evidence of a faint atmosphere or erupting gas plumes; and map the nighttime temperature of the surface. These and other results will be analyzed in the weeks to come.

Channel: Science & Technology
Uploaded: September 17, 2007 at 2:47 am
Author: BrunoTheQuestionable

Length: 00:03:34
Rating: 4.63
Views: 4780

Tags: Iapetus Fly-by

Video Comments:
hulaqde (March 20, 2008 at 5:18 pm)
Arthur C.Clarke is truly enjoying this...and then some...rest easy and may Iapetus be within your grasp....R.I.P.
SilentInsomnia (December 11, 2007 at 7:20 am)
What is the whitish sphere (11 o'clock) that comes in around 3:13? It looks like a still of a sphere rising out of the surface??
theboydanny (January 31, 2008 at 12:00 am)
photojournal . jpl . nasa . gov / catalog / PIA08372
Take a look at the hig-res one, looks like the other side of the crater is catchin' some Sun.
MichealTea (November 28, 2007 at 3:33 am)
I Always thought that the ridges shown in the video was that of tectonic plates shifting underneath, but it shows a polar terrain. Now the dark blue,Im sure that is the warmest polar regian. The dark blue could be warm water trapped underneath the surface. And the bright red regian is as said. "Ice".
BrunoTheQuestionable (November 29, 2007 at 12:46 am)
The dark side is warmer than the bright side, because of absorption of sunlight. This causes sublimation of any exposed ice on the dark side, and its precipitation on the bright side and at the poles. The red region in the ultaviolet image in the video is the polar ice. The dark blue region is the dark material. Liquid water may once have existed on Iapetus, but it is far too cold now.
davidchenard (December 25, 2007 at 8:55 pm)
Perhaps it was a once the rings of the moon that fell to the surface.
SkepticalZombie (November 6, 2007 at 6:23 pm)
The equatorial ridge of Iapetus looks much like the mid-Atlantic ridge of our little planet.

There goes that pattern-seeking element of my brain. Cool video though, thank you again, Bruno!
BrunoTheQuestionable (November 6, 2007 at 6:40 pm)
Interesting observation. I wonder if its origin is "volcanic" but formed by water instead of lava.
SkepticalZombie (November 8, 2007 at 3:14 am)
As far as I understand it, that is one of the leading theories.
BrunoTheQuestionable (September 19, 2007 at 9:19 pm)
Thanks - its appreciated.