Show Date: January 11 , 2005

DEATH STARS AND WARNING SYSTEMS
Pam Eastlick for the Marianas Variety

Greetings and welcome to The Deep column and the deepest radio show on Earth. The Deep is the science talk radio program that takes you from the depths of the ocean to the farthest reaches of the universe. This week on The Deep hosted by Jim Sullivan and aired at 6:00 Wednesday evening on K-57, our special guest will be Chip Guard from the National Weather Service. He’ll talk about the Pacific Tsunami Warning Center and how it works. If there had been a similar system in the Indian Ocean, the number of casualties from the recent tsunami could have been greatly reduced. We’ll also talk about new revelations from the Cassini spacecraft in orbit around Saturn.

ASTOUNDING SPACE MYSTERY
Saturn has at least 30 moons and many of them are mysterious. Titan, the second largest moon in the solar system, is covered with a brownish haze made of organic chemicals that’s very similar to smog on Earth. This Thursday, 14 January, the Huygens probe will scream into Titan’s atmosphere and send back pictures all the way to the surface, whatever the surface may be. Huygens has a large parachute and scientists hope for a soft landing but Huygens is also designed to float. Keep watching the news for updates about this amazing mission.
Titan is certainly bizarre, but one of the strangest moons in the Saturnian system is Iapetus. Iapetus was discovered by Giovanni Cassini in 1671. Iapetus is about 900 miles across (about half the size of our moon) and was only a small dot to Cassini. As telescopes improved, astronomers began to realize that there was something very strange about Iapetus; it was half-black and half-white.
The Voyager spacecraft flew by Saturn in the 1970’s and virtually all we knew about this harlequin world came from these intrepid explorers. Unfortunately, Iapetus orbits much farther from Saturn than most of the other moons and the Voyagers didn’t get too close as they whizzed by Saturn.
They revealed that Iapetus is, indeed half-black and half-white. The ‘black’ side is actually very dark red and it’s the ‘leading’ side as Iapetus orbits Saturn. Astronomers think the dark material might be dust from other moons kicked up by meteor impacts, but since it seems to be thickest in crater floors, it may be internally generated.

Then, last summer, the Cassini spacecraft arrived at Saturn. Its four-year mission involves several flybys of Saturn’s major moons and on New Year’s Day, Cassini made its first close approach to Iapetus. The pictures returned show one of the solar system’s strangest sights.

On the dark hemisphere (which had never had its picture taken), astronomers were astounded to see a long narrow ridge that lies almost exactly on the equator of Iapetus. This ridge is over 800 miles long and uniformly about 12 miles across. But the truly amazing thing is that it rises an astounding 12 miles above the rest of the surface. The ridge is about three times higher than Mt. Everest and almost as tall as Olympus Mons, the solar system’s tallest mountain.

What caused it? Nobody knows, but look at the accompanying picture, don’t you think it looks surprisingly like a seam? Is Iapetus a constructed satellite? Probably not, but you have to agree that that ridge is certainly one of the solar system’s deepest (tallest?) mysteries.

SEEING THEM COMING
We are still assessing the magnitude of the costliest tsunami in recorded history. Although nothing could have stopped the property destruction, most experts agree that the toll in human lives could have been greatly reduced if the Indian Ocean had had a tsunami warning system in place.
Tsunamis aren’t frequent events in the Indian Ocean, but they are relatively common in the earthquake-prone Pacific with its ‘Ring of Fire’. A massive earthquake off the coast of Chili in 1960 caused destructive tsunami waves as far away as Japan and prompted the establishment of the International Tsunami Warning System and the Pacific Tsunami Warning Center (PTWC) both headquartered in Hawaii. The PTWC is operated by the National Weather Service and this week on The Deep, Jim will have Chip Guard from the NWS as his guest. Learn all about this network that could save thousands of lives!

There will be other important news on The Deep this week. Don’t miss it! You can also log on to www.thedeepradioshow.com for more information.