View Full Version : Iapetus' Darker Side

2006-May-16, 07:19 PM
SUMMARY: This Cassini image shows the darker side of Saturn's moon Iapetus. Scientists aren't sure why, but Iapetus' leading hemisphere is much darker than its trailing hemisphere. At the top of the image, it's possible to see a large impact basin 400 km (250 miles) wide. Cassini took this photograph on April 4, 2006, at a distance of approximately 1.4 million kilometers (900,000 miles) from Iapetus.

View full article (http://www.universetoday.com/am/publish/saturen_mystic_iapetus.html)
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2006-May-22, 12:39 PM
Certainly one of the longer lasting mysteries of the solar system.
I wonder if Cassini will ever solve it. And if not it, then perhaps some future Saturnian probe.

2006-May-22, 01:56 PM
I don't think it's that big a mystery. The leading side is dark and obviously picking up debris, while the trailing side is bright. Why Iapetus is the only moon that's this way may be the real mystery.

2006-May-22, 03:18 PM
Clarke had an answer in '2001' (the novel, not the film).

I wonder if a collision with a comet did the job, dusting the moon in carbon rich dirt. It would make sense for a single comet to intercept this moon in such a way, IMO.