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International Edition Winners 2011: Romania, Target 2, Grade 9-12

International Edition Winners 2011: Romania, Target 2, Grade 9-12


Raluca Turcu and Maria Uzum
Rhea and Titan
Rhea and Titan
Raluca Turcu and Maria Uzum

9th Grade
Tudor Vianu National High School of Computer Science
Bucharest, Romania

Teacher: Ioana Stoica



"In ancient times, “Titan’’ and “Rhea’’ were two words with great spiritual valence, being related to mother Earth. Nowadays, the same two names could be the answer to many foremost questions about our origin and about the existence of life on other celestial bodies.

Rhea is Saturn’s second largest moon, with a density of 1,236 g/cm3. It is believed to be made of 25 percent rock and 75 percent water. Its particularity is the capacity of retaining a thin, externally generated atmosphere that afflicts Saturn’s magnetosphere. In other words, the cratered terrain on the moon may be caused by the generated attraction between it and particles of the crashed orbiting asteroids in Saturn’s A ring. Rhea’s other face, the one not pointing at its planet, has a rather wispy terrain. One goal that the Cassini spacecraft should settle is whether the tectonic activity generated by a rocky core or the endogen activity has caused the irregular surface.

The Voyager missions around Saturn have pointed out the probability of the existence of an internal liquid water ocean. If so, this should imply a heating source in Rhea’s core. So, another question Cassini should answer is whether Rhea has developed a radioactive field that provides heat or whether the ice is melted due to the high pressure inside it or it’s interaction with Saturn.

It is believed that rather than gas, Rhea’s atmosphere could contain solid material, thus making it possible for the moon to have a ring system. Even if this theory was rejected, there is still evidence reinforcing it. Three fourths of the equatorial circumference is covered by a range of spots visible in UV light. Observations from several instruments suggest that this is caused by material in the form of grains and boulders of small size which orbits Rhea as an equatorial debris disk. Another answerable question would be if Rhea is the only natural moon that has a ring system.

Titan is Saturn’s largest natural satellite and the only explored one besides the Moon. It is known in the scientific world for having a thick opaque orange atmosphere which contains complex particles resembling to the ones Earth had 4 billions years ago. The scientific research done in the last decade has proved that conditions on Titan are similar to the ones on Terra. But, however familiar Titan’s environment may seem, it is in fact exotic. Liquid methane and ethane flow on titan, creating geographical characteristics that resemble the ones on Earth.

Could Titan develop life? And if it is possible, hasn’t it already happened? Scientists are considering the existence of methanogenic life, which is thought to be able develop strategies to overcome the seemingly unfavorable conditions on the moon, using catalysts in order to accelerate biochemical reactions.

In conclusion, we consider the two moons to be able to give us answers about prebiotic Earth, allowing us to get a glimpse of our formation and development."