It will conduct a gravity experiment

Apr 27, 2010 09:06 GMT  ·  By

Since July 2004, the NASA Cassini spacecraft has been conducting remarkable scientific observations around the gas giant Saturn. In addition to looking at the planet and its intricate ring system, the probe has also carried out numerous flybys of its many moons, providing astronomers with a wealth of data about many of them, and their interactions with the ring system and Saturn's magnetosphere. An additional flyby from this series will take place today/tomorrow, as Cassini will swing by the peculiar moon Enceladus.

According to mission managers, based at the NASA Jet Propulsion Laboratory, in Pasadena, California, the spacecraft will fly low above the surface of the moon, in order to conduct an intricate and sensitive gravity experiment. During the mission, planetary scientists hope to be able to extract a wealth of data as to the internal composition of Enceladus, which is undoubtedly one of the most interesting bodies in our solar system. The scheduled flight path will take the space probe about 100 kilometers (60 miles) above the surface, at the point of closest approach. This will take place on April 27 Pacific time and April 28 UTC.

One of the things that makes Enceladus stand out from the crowd of Saturnine moons is the fact that astronomers believe it may house a liquid ocean. Naturally, liquid water cannot endure in the frigid temperatures of its surface, but the experts say that it may be buried several kilometers, under a thick ice crust. But the real interest is the south polar region, which featured cracks known as tiger stripes. Through these landscape features, Enceladus emits plumes of water and ice vapors, which apparently play an important role in fueling one of Saturn's rings with material.

The new flyby will take Cassini straight through the plume emissions. During the flight, the instruments aboard the spacecraft will remain silent. In fact, the only thing experts need in order to conduct this experiment is a steady link between the probe and the NASA Deep Space Network on Earth. “Detecting any wiggle will help scientists understand what is under the famous "tiger stripe" fractures that spew water vapor and organic particles from the south polar region. Is it an ocean, a pond or a great salt lake? The experiment will also help scientists find out if the sub-surface south polar region resembles a lava lamp. Scientists have hypothesized that a bubble of warmer ice periodically moves up to the crust and repaves it, explaining the quirky heat behavior and intriguing surface features,” the JPL team says in a statement.