Feeds

Cassini closes in on Iapetus

Fly-by of an odd-ball moon

Seven Steps to Software Security

Saturn watchers on the Cassini mission are preparing for another fly-by, this time of the oddly shaped moon Iapetus.

Two views of Iapetus, ultraviolet and visible light. Credit: NASA

The Cassini probe is set to pass within 1,600 kilometres of the moon, roughly 100 times closer than the last encounter in 2004. It is also the last time the probe is scheduled to fly past the moon, and mission scientists are keen to capture as much data as they can.

Iapetus has long been a puzzle to scientists. It has a two-tone appearance, where the leading edge is far brighter than the trailing hemisphere. The difference is similar to the contrast between fresh snow and black tar.

Several possible explanations have been put forward, but no consensus has yet been found: could the dark matter, which has a slightly red tinge, be residue from another moon? Could it come from inside the moon? Is it comet debris, or the result of meteoroid impacts?

JPL scientist Amanda Hendrix, of Cassini's ultraviolet imaging spectrograph team, speculates that an event that disrupted the moon Hyperion, which has a similarly dark red tint, could be responsible for depositing the material on Iapetus.

Meanwhile, Dale Cruikshank, at NASA's Ames Research Center, suggests that the dark matter could be pre-biotic organic compounds: the raw stuff of life.

The moon also has a ridge of high mountains running exactly around its equator. The origin of these peaks remains mysterious, too.

The scientists involved with the mission hope this fly by will help clear up some of these mysteries. They are planning to turn Cassini's Synthetic Aperture Radar towards the little world to collect data on the size of various surface features. They also plan to study the chemical composition of the surface, search for any evidence of an atmosphere or erupting gas plumes; and map the night-time temperature of the surface.

The probe will make its closest approach on September 10th. ®

The Power of One eBook: Top reasons to choose HP BladeSystem

More from The Register

next story
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Malaysian Airlines flight MH17 claimed lives of HIV/AIDS cure scientists
Researchers, advocates, health workers among those on shot-down plane
World Solar Challenge contender claims new speed record
One charge sees Sunswift travel 500kms at over 100 km/h
Mwa-ha-ha-ha! Eccentric billionaire Musk gets his PRIVATE SPACEPORT
In the Lone Star State, perhaps appropriately enough
SMELL YOU LATER, LOSERS – Dumbo tells rats, dogs... humans
Junk in the trunk? That's what people have
All those new '5G standards'? Here's the science they rely on
Radio professor tells us how wireless will get faster in the real world
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
The Essential Guide to IT Transformation
ServiceNow discusses three IT transformations that can help CIO's automate IT services to transform IT and the enterprise.