EXPECTATION AND REACTION
HISTORICAL EXPECTATIONS OF SATURN AND ITS MOONS
What exists beyond our world has always been a fascination of mankind throughout the centuries. Christiaan Huygens was no exception, he speculated on what might be discovered on other worlds and their moons in his book The Celestial Worlds Discovered (1698). Huygens assumed that the moons of other planets including Saturn were probably similar to our own moon:
“But this we may venture to say, without fear, that all the Attendants of ...Saturn are of the same nature with our Moon.”
Huygens considered the nature of the Earth’s moon and drew conclusions, which he then applied to Saturn’s moons. Huygens thought the mountains and valleys visible on the moon might "easily be occasioned by natural causes" , rather than made by any inhabitants. Nor does Huygens believe that any sea, river, water or clouds had been observed on the Earth’s moon:
“Tis certain moreover, that the Moon has no Air or Atmosphere surrounding it as we have.”
When referring directly to the moons of Saturn, Huygens thought that it would be odd if all those celestial bodies were barren of life:
“What! and must all these Moons round...Saturn be condemned to the same uselesness? I do not know what to think of it, because I know of nothing like them to found a conjecture upon. And yet ’tis not improbable that those great and noble Bodies have somewhat or other growing and living upon them, tho very different from what we see and enjoy here. Perhaps their Plants and Animals may have another sort of Nourishment there. Perhaps the moisture of the Earth there is but just sufficient to cause a Mist or Dew, which may be very suitable to the growth of their herbs.”
These expectations of Huygens were not so very different to contemporary hopes of alien environments and life.
CONTEMPORARY EXPECTATIONS OF SATURN AND ITS MOONS
Preconceptions of Titan before the landing of Cassini–Huygens were more informed and detailed due to flybys of Titan by recent spacecraft, which gave scientists a more accurate picture of its atmosphere and composition. The scientists at NASA and ESA envisioned a moon that was similar to planet Earth in its infancy, but because of the conditions found at 1.5 billion kilometres (900 million miles) from the Sun it would be frozen. Many thought that the entire surface of the Titan, or at least large portions of it, would be covered in an ocean of ethane, acetylene, propane, and other hydrocarbons, that could be as deep as 1 kilometre (˜2/3 mile). However from ground–based studies on Earth, it was surmised that there would be lakes and seas, and erosion caused by the movement of hydrocarbons, but no global ocean.
It was expected that Titan would have winds and be covered in ice, as solid as rock on Earth, like many other bodies in that area of the solar system. But it was not possible to determine either of these things from the Earth, and so it was up to Cassini–Huygens mission to provide the answers to these questions.
Space exploration is one area of science that has great appeal to the general public. The discoveries from voyages into space are chronicled in a way that few other scientific endeavours are by the media. The Cassini–Huygens mission is no exception to this rule.
Over the course of the Cassini–Huygens journey, over 374,000 pages of information has been generated on the Internet concerning all aspect of the mission. The coverage that Cassini–Huygens has received ranges greatly. Some articles debate the scientific purpose of the mission, while others unveil the spectacular images captured on the mission. The coverage includes the people behind the mission, the larger questions of life and humanity that may arise from the research, and the transmission of facts, achievements, and milestones, by which we as the public may judge Cassini–Huygen’s success.
Listed below are samples of the different types of material that were published on the Cassini–Huygens mission in the media.
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