but where were the spiders?
If ever we needed the manfromMars it was surely in this story...
Scientists have revisited a 2015 sighting of water on the surface of Mars and revised the theory to suggest what we saw was sand, and probably not even damp sand at that. In a new paper titled Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water seven authors from United States Geological …
@Aladdin Cave
...a girl from Mars
Helen Sharman?
If Musk gets his skates on, he could offer the "Girl from Mars" a trip to Mars
She is fully in support of manned missions to Mars. And she herself would love to be on the maiden voyage.
“It won’t happen now, but if I was younger I’d do it in an instant,” she says. “I’d still love to go back up. It’s a wonderful thing.”
I'd like to see some data on the sand's properties. Not any type of sand can be used to mix concrete. The properties you want the concrete to have and the type of cement that is available are also vital factors. (Fun fact: Saudi Arabia has to import sand to make some types of concrete.)
Being able to build concrete structures on Mars would help longtime Mars missions, from landing pads to crew shelters etc.
Ideally Mars could have types of sand that cas cement-like properties, like puzzolani. The Romans used that for structures like the foundations of the Coliseum or the cupola of the Pantheon - 2,000 years ago.
Wait What? Someone is selling sand to the Arabs? Next you'll be telling me Eskimos buy ice.
I had to search for that and apparently (it's the internet after all) Australia also export Camels to Saudi Arabia as well as sand.
Further research gives me this book,
"Ice to the Eskimos: How to Market a Product Nobody Wants"
That's the B Ark right there.
> And now, not even that is true.
You are misunderstanding - Mars' wet past is in little doubt, in fact we are pretty sure it had oceans of water on its surface at one point. This discovery has to do with whether liquid water is _currently_ present, even for brief periods, on the Martian surface. However, due to its now much thinner atmosphere, today water can only exist in liquid form at temperatures up to 10 degrees centigrade, above which it would boil, making the current presence of liquid water rather unlikely. Which is why the original story was so unexpected, and today's rather less so.
It may also be worth pointing out that this by no means implies that there is no water Mars - in fact there is plenty; enough to cover the whole planet to a depth of 35 meters. It's just that it mostly exists as a solid.
Based on the little Martian exploration we've done, it appears that it took billions of years for the solar wind to create what we see today. Yes, the solar wind will eventually strip any Martian atmosphere, assuming we don't simply* develop an artificial planetary magnetic field. This will take millions of years. Unless your definition of long term human use is in time frames longer than humans have existed for, you have not stated a case against long term human use of Mars.
* Simple for a civilization with the technology to construct a colony on anther planet than is large enough to justify the effort in nuking the poles. We know how to build Dyson-Harrop satellites today. Dyson-Harrop satellites can harness solar energy to create large magnetic fields in space. The solar wind is made up of charged particles, principally protons and electrons. Charged particles can be influenced by magnetic fields. A constellation of Dyson-Harrop satellites in Martian orbit** therefore can deflect the solar wind. I expect, if a better method is not developed, this style of system can be refined to capture the solar wind. As protons plus electrons equals hydrogen, this is one potential way to import lost-cost hydrogen(We also end up with helium and traces of heavier elements) to Mars. The same system could also be used to give the Moon it's own magnetic field, allowing a Lunar atmosphere.
** You may have seen the proposal for a similar shield placed at the Sun Mars L1 point. This doesn't work because the solar wind hits from the side. The solar wind is influenced by the Sun's magnetic field, which is dragged by the Sun's rotation. The Sun's magnetic field, when viewed from above the orbital plane, looks like a pinwheel.