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Journey to Mars - Text Only

Mars is a neighboring planet that has intrigued us for hundreds of years. It offers the possibility that we will find another world where life might have begun. Observations of Mars with telescopes in the early 1900s indicated that perhaps Mars and Earth were very similar. In fact, the suggestion was made that Mars may have been an older version of Earth--perhaps a civilization had been present and was now dying.

One of the questions we had when we sent our first spacecraft was exactly how similar is Mars. Our surprise has been in how different the two planets are. We believe Mars was once a wet, warm world. Perhaps with streams, lakes pooling, perhaps even oceans. And at this time perhaps, there were the conditions necessary for life to begin.

Since that time, the 3-4 billion years that have past have seen an enormous change in its climate. Today, Mars is an arid world, it's the thin atmosphere, it's devoid of any evidence of life on its surface. Whether there was life there or not we don't know. But what we can say is that there's plenty of evidence that water was once present on the surface.

Our earlier missions, the Viking landers and its orbiters, gave us an initial view of the planet. But now with MGS [Mars Global Surveyor], we have a view of the topography of the planet, we have an understanding of the circulation of its atmosphere, and we have an understanding of the way in which water may have coursed over its surface in the distant past.

At every turn, our questions seem to bring about more questions. We had expected to see minerals, minerals that could only be formed in the presence of water, and that those minerals would be at the mouths of the channels where we see that water must have moved. But we don't see those minerals. And so our surprises are as much as what we have not seen as in the discoveries of things unknown.

Mars Odyssey is a mission that takes a step in a trail that we outlined almost 20 years ago to determine exactly where the environments might have been suitable for the origins of life. If we find those environments with the Mars Odyssey, we are going to go to those locations, we're going to set down rovers, landers, do surface examinations and perhaps return samples from those sites.


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