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International Edition Winners - 2013: Turkey, Target 1, Grade 10

International Edition Winners - 2013: Turkey, Target 1, Grade 10

Nuriye Varo?lu
Target 1, Iapetus
Nuriye Varoğlu

Grade: 10

School: DarĂ¼şşafaka High School

City: Istanbul

"Cassini mission continues to observe and explore the Saturn system since 1997. It is going to be sent again to space in the following years to observe Saturn itself or one of its two moons: Iapetus or Dione. I think the best target for this upcoming observation of Cassini spacecraft is Target 1: Iapetus.

Iapetus was first discovered by Giovanni Domenian Cassini in 1671. Then in 1980, NASA's Voyager 1 showed that one hemisphere of Iapetus is extremely dark, while the other one is light-colored (just like Cassini predicted). Moreover, these two tones are so sharply divided that no one seems to know why. Today, it is still a mystery how the dark matter on the leading hemisphere is formed. There is a theory which states that the dark material could have come from Saturn's moon Phoebe. However, color of the matter on Phoebe does not match with Iapetus' dark matter. There are some other theories for this phenomenon; they all seem to have shortcomings though. Thus the mystery will be unlocked only with more observations. If Cassini's cameras are pointed to Iapetus and have a closer look at the material, it is for sure that something constructive will be found.

Another puzzling physical characteristic of Iapetus is its walnut-shape. During Voyager 2 flyby of Iapetus, a line of mountains was noticed. Then in 2004, Cassini flyby concluded that an equatorial mountain ridge extends 12 miles into space above Iapetus' surface. No one knows yet how the ridge formed.

Some scientists think the ridge formed at an earlier time when Iapetus was rotating faster than it does today as it would be abnormal for such a slow-spinning body to form the shape. Another theory is that the ridge might be a material left from the collapse of a ring. There are some other hypotheses, all seem to be logical. Yet, none of them explains why the equatorial ridge is only on the dark side. When Iapetus' entire surface is imaged in high resolution, we will find an answer.

I am sure some new observations by using the Narrow Angle Camera of Cassini will help us solve the unique characteristics of Iapetus. The results are going to teach us a lot about outer space, especially about Saturnian system.

As humans we are always searching for something new to enrich our knowledge of the universe and our location in the universe. It is for sure that we are succeeding in it since we continuously learn as we observe. Therefore, I have no doubt that Saturn and Dione will illuminate us by giving some useful information as well. However, I strongly believe that the most interesting scientific results will be given by the moon Iapetus as it is the most unusual body among three targets. That is why Target 1 will make the greatest contribution to the science."