In case you have not heard, NASA announced today that they have evidence that water flows on Mars. That’s the present tense, note. Not flowed some time ago – flows currently (albeit perhaps only in intermittent bursts). Here’s the link to their announcement. The picture:
“These observations give the strongest evidence to date that water still flows occasionally on the surface of Mars,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program, Washington.
The atmosphere of Mars is so thin and the temperature so cold that liquid water cannot persist at the surface. It would rapidly evaporate or freeze. Researchers propose that water could remain liquid long enough, after breaking out from an underground source, to carry debris downslope before totally freezing. The two fresh deposits are each several hundred meters or yards long.
Go to the announcement to read more about the programme of photographing the surface of Mars that turned up these images, and for more on the interpretation of the images.
Now this is nice and all, but I still find that sentences like this annoy me as more than a little limiting:
Liquid water, as opposed to the water ice and water vapor known to exist at Mars, is considered necessary for life.
Would it hurt the impact of these stories to modify “life” to “life as we know it”, or “the kind of life we’ve seen thus far” or (fill in the blank)?
(To be continued…)