This is relevant for search for life on Mars. Not relevant for water supply.
Quote from: guckyfan on 11/20/2017 04:32 pmThis is relevant for search for life on Mars. Not relevant for water supply.I disagree. These streams were one of the very few pieces of evidence pointing to abundant water ice on mars (at least in equatorial regions). All plans involving ISRU fueling (and Musks plan specifically) require copious amounts of easily accessible water. From what I've read on these forums the plan would be to land on mars and then - mine the glacier. Where's that glacier? It's not showing up on Mars Odyssey neutron or gamma ray data. AFAIK, it's not showing up in any data. That's a big problem in my opinion.
large amounts of water on widespread areas of Mars.
Quote from: whitelancer64 on 11/21/2017 02:26 pmlarge amounts of water on widespread areas of Mars. Poles
See http://forum.nasaspaceflight.com/index.php?topic=41680.msg1612647#msg1612647 or the article that started that thread: https://www.space.com/34811-mars-ice-more-water-than-lake-superior.html
The RSLs were never supposed to have any connection to water ice. They were supposed to be formed by deliquescent salts during seasons of high humidity. the new hypothesis has no impact on our understanding of the distribution of water ice.
Very widespread (and 300 km resolution) within 1 m of the surface down to latitudes of about 50 degrees N and S.
Probably common at deeper depths closer to the equator. Possibly closer to the surface close to the wquator as well, in sheltered regions less than 300 km across.
Quote from: dwheeler on 11/21/2017 04:58 pmSee http://forum.nasaspaceflight.com/index.php?topic=41680.msg1612647#msg1612647 or the article that started that thread: https://www.space.com/34811-mars-ice-more-water-than-lake-superior.htmlThanks. Interesting. Is there a link to the original paper? I'd like to know how they resolve the huge discrepancy with the Mars Odyssey data. The "lake superior" is located in one of the driest places on the planet according to odyssey. Also their argument seems to be that they see surface features that kind of suggest ice underneath so they interpret the radar data assuming there's ice underneath. Interpreting ground penetrating radar data is tricky on earth where we have all sorts of additional data to calibrate against. I suspect there may be many pitfalls for mars data. But I think I kind of see what they see on the radar data, so I'm hopeful. Quote from: Dalhousie on 11/21/2017 10:08 pmThe RSLs were never supposed to have any connection to water ice. They were supposed to be formed by deliquescent salts during seasons of high humidity. the new hypothesis has no impact on our understanding of the distribution of water ice.It's all connected. I mean, how were these seasons of high humidity supposed to come about? Now it looks like there are no seasons of sufficient humidity to cause such flows - Mars became a drier place.Quote from: Dalhousie on 11/21/2017 10:10 pmVery widespread (and 300 km resolution) within 1 m of the surface down to latitudes of about 50 degrees N and S. Are you talking about the Mars Odyssey data? Due to the funky scale what looks blue like the ocean at 50 degrees is actually dry as bone Quote from: Dalhousie on 11/21/2017 10:10 pmProbably common at deeper depths closer to the equator. Possibly closer to the surface close to the wquator as well, in sheltered regions less than 300 km across.Can't fill your tank with theories.
Why argue that water isn’t present close to the surface? Ice was photographed in-situ by the Phoenix lander and ice has been observed scattered around fresh impact sites from orbit. This isn’t just some arcane form of remote-sensing!
Why argue that water isn’t present close to the surface?
Ice was photographed in-situ by the Phoenix lander
and ice has been observed scattered around fresh impact sites from orbit.
Quote from: Bob Shaw on 11/23/2017 07:58 amand ice has been observed scattered around fresh impact sites from orbit. Any sources for that?
Quote from: Bob Shaw on 11/23/2017 07:58 amWhy argue that water isn’t present close to the surface? Look, I want to believe, but I need to be aware of my own cognitive biases as well. So I want to separate the evidence from conjecture and wishful thinking.
The Gamma Ray Observatory data was always conclusive proof to me that there is water flowing thru Valles Marineris. Inferring hydrogen content of minerals as absolute proof of water always seemed like a pretty honky-dory logical inference to me.However, this news from USGS really makes me wonder why there hasn't been much news (or for that matter) interest with water on Mars. If you plot Google searches over time, there has been some transient interest with water on Mars. As a comparison, I plotted the interest with the Oort Cloud. So, if water on Mars doesn't exist... I'd conclude that the Oort cloud doesn't exist as well. For whatever reason there is no interest with water on Mars, or the Oort Cloud, in Wyoming.