logicize:<br />It seem to me that we certainly don't know enough about extra-solar planets to say that water 'has been found' on one.<br /><br />Me:<br />I agree with this and I think whats probably going to happen is that in future years there will be missteps. Its not all that uncommon. But in looking at the article, some things to keep in mind. It was written by a reporter and reporters or magazine article writers tend to spice up their stories to get them published. The headline reads "Water Found in Extrasolar Planet's Atmosphere" which is just as you mentioned. But when reading the article, you'll notice water vapor is mentioned rather than water. Big difference as it should be easier to detect water vapor than liquid water.<br /><br />In the article excerpt below:<br /><br />The discovery, announced today, means one of the most crucial elements for life as we know it can exist around planets orbiting other stars.<br /><br />Me:<br />Note they say can exist as opposed to does exist. Then go on to see how they detected water vapor and you can see how it would be possible in a planet with a sufficiently thick atmosphere. Mars essentially has so little atmosphere that even water vapor would be nearly impossible to detect. But with mars, the evidence for water lies more in what can be seen on the surface. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>