Saturday, August 6, 2011

Liquid water on Mars

Yesterday, the journal Science published a paper by planetary scientist Alfred S. McEwen, along with colleagues Lujendra Ojha, Colin M. Dundas, Sarah S. Mattson, Shane Byrne, James J. Wray, Selby C. Cull, Scott L. Murchie, Nicholas Thomas, and Virginia C. Gulick entitled "Seasonal Flows on Warm Martian Slopes."

In it, they analyze new high-resolution images from a special camera on NASA's Mars Reconnaissance Orbiter and argue that ongoing seasonal temperature changes appear to be causing what may be salty water near the surface of Mars to flow in liquid form even today, which is the first time anyone has determined that this is happening. The article's lead author, Dr. McEwen of the University of Arizona, is the principle investigator on that camera, which is called the HiRise camera (for High Resolution Imaging Science Experiment).

Planetary scientist Oded Aharonson says, "This is the best evidence yet of liquid water emerging on the surface of Mars" in an accompanying story in Science Now entitled "Is Mars Weeping Salty Tears?" That story argues that the salty content of the water lowers the freezing point, and that the surface may get close to freezing, warm enough to allow meager flows (which have been designated "recurring slope lineae," or RSL) to melt and make their way down steep crater slopes prior to drying up or evaporating.

A NASA article published Thursday on the same subject says that sunlight sometimes warms temperatures to 80° F in parts of the Martian surface. In this interview which aired on NPR yesterday, Dr. McEwen confirms that the surface can get up to "a balmy eighty degrees Fahrenheit or so, maybe even warmer" but that at night it gets much colder and thus the temperatures just a few inches below the surface stay extremely cold. He notes that "some of this activity occurs when the surface temperatures are too cold for pure water to melt," which indicates that the water (if it is water) must be salty, and explains the temperatures described in the Science Now article referenced above. He also notes that the atmospheric pressure is so low on Mars that pure water would actually boil at temperatures near freezing, but that salty water which has a higher boiling point would not.

The abstract for Professor McEwen's paper notes that "the exact mechanism and source of the water are not understood." However, it is impossible (for me) not to point out that these findings are very much consistent with the predictions of the hydroplate theory, as discussed in this previous post entitled "Let's go to Mars," published before these new findings became known to the general public (or at least to me).

In that post, we saw that hydroplate theory creator Dr. Walt Brown believes that salty water remains frozen at the surface of Mars and that it came from above in the form of comets and icy asteroids which bombarded the Martian surface (creating the craters where this activity is being noted). According to his theory, this water originated on earth and was blasted into space during the violent eruption of underground water which initiated the flood event. We have seen that there are hundreds of data points on earth which appear to support such an event (some of those are described in the posts linked in this previous post).

We should all congratulate the scientists who have discovered this ongoing dynamic activity on the surface of Mars and wish them the best with their continuing investigation of this phenomenon. Additionally, it would not be a bad idea for them to become acquainted with the hydroplate theory, no matter how different it is from the reigning conventional theories, because it provides an explanation which appears to shed light on these recent findings, as well as an explanation which accords well with phenomena here on earth which can be studied in person.