8 ms·
Is water on Mars even exciting? We're already quite certain there is a ton of water on Mars... in the form of ice. The exciting discoveries are evidence of
by BrazzVuvuzela 5y ago
Is water on Mars even exciting? We're already quite certain there is a ton of water on Mars... in the form of ice. The exciting discoveries are evidence of liquid water.
> The bulk of the northern ice cap consists of water ice; it also has a thin seasonal veneer of dry ice, solid carbon dioxide. Each winter the ice cap grows by adding 1.5 to 2 m of dry ice.
> The part of the cap that survives the summer is called the north residual cap and is made of water ice. This water ice is believed to be as much as three kilometers thick.
https://en.wikipedia.org/wiki/Martian_polar_ice_caps https://en.wikipedia.org/wiki/Martian_polar_ice_caps
That's a lot of water!
- gunfighthacksaw 5y agoFor anyone born in the 20th century I’d think so. If you’d have said there was water on mars in 1970 you’d have been met with disbelief. 1980? 1990? Later?
- BrazzVuvuzela 5y agoI think this is a failure of science education more than anything else. The polar ice caps of Mars were first observed in the 17th century. https://en.wikipedia.org/wiki/History_of_Mars_observation#Early_telescope_observations https://en.wikipedia.org/wiki/History_of_Mars_observation#Ea...
- varjag 5y agoIt was observed simultaneously as canals and vegetation were "observed", and roundly discarded by 1970s. Water on Mars remained unconfirmed until this century.
- interroboink 5y agoThough I distinctly remember reading in an encyclopedia from the '70s that certain large dark regions on the Martian surface were believed to be thick vegetation (: I'm not kidding! From [1]: "As recently as the early 1960s, it still seemed possible to a few astronomers that the dark regions had some kind of plant life because they seemed to darken each summer as if plants were growing in response to sunlight." [1] https://www.jpl.nasa.gov/images/pia02362-the-dark-surfaces-of-mars-mantles-and-sand-sheets https://www.jpl.nasa.gov/images/pia02362-the-dark-surfaces-o...
- Veen 5y agoYes, I remember reading books from the 60s my grandmother got from a charity shop. They had wonderful illustrations of Mars with vegetation and where the canyons discussed in the article were canals full of water. It's easy to forget just how much we've discovered about the other planets in the solar system in the last 50 years.
- paxys 5y agoThere is so much science fiction writing from the golden age and beyond, up to the 60s and 70s, which prominently features Martians and Martian cities. Mars having alien life was a massive source of speculation among the public at that time. While the stories are still great, reading them today I can't help but go "nah we've been to Mars, there's nothing there". Makes me think about how soon sci-fi written today will get similarly outdated.
- johnnywasagood 5y agoI remember a sci-fi novel from the 60s or 70s, where a forgotten punch card was the only artifact left over from aliens long gone. I think that something similar awaits modern science fiction in 50 years.
- dustintrex 5y agoI'm reading Red Mars at the moment, written in the 1990s and set in the 2030s, and a cluttered lab is described as having piles of floppy disks lying around. So, yeah.
- throwawayboise 5y agoMakes one wonder what science of today will be looked upon with quaint humor in 50 years' time.
- cmehdy 5y agoAstronomy Picture of the Day on April 1st 2005: NASA finds water on mars[0]. [0] https://apod.nasa.gov/apod/ap050401.html https://apod.nasa.gov/apod/ap050401.html
- coenhyde 5y agoIt is very exciting in the equatorial regions as it was typically assumed that because of the high summer temperatures (~70°F), any ice would melt and the water would evaporate. Valles Marineris would be an excellent location for a human settlement because of these warmer temperatures and the higher atmospheric pressure in the canyon. If there is water there as well then it ticks all the boxes.
- londons_explore 5y ago> higher atmospheric pressure But the pressure is still effectively nil. It's far below what would be needed for humans to venture outdoors, and makes a negligible difference to the strength required for pressurised buildings.
- BrazzVuvuzela 5y agoI believe it would make it easier to land supplies there though, since there is more atmosphere to aerobrake with.
- vanattab 5y agoCan you aerobreak all the way into the cannon though?
- BrazzVuvuzela 5y agoEvery bit helps, right? Even if you're using retrorockets by the time you're that low, atmospheric drag should still be helping.
- zardo 5y agoIt is a few hundred kilometers wide.
- coenhyde 5y agoAbsolutely but every little bit helps. A thicker atmosphere also means less radiation, thus less radiation shielding required. I don't have numbers on hand but from what recall it is a significant enough of a difference to worthy consideration.
- echelon 5y agoEvery deposit of water, even as ice, opens a new series of inquiry. Suddenly you have new regions, geographies, biogeochemical hypotheses, and potential support for life. More history, more to explore. New sites give us more to consider for future missions and broaden the set of experiments we want to conduct. I'd much rather keep finding water, even as ice, then have the planet run dry. It only increases the odds.
- basementcat 5y agoOne of the interesting consequences of water on Mars is the fact that it can be used to make methane and oxygen (used by both SpaceX's Raptor and Blue Origin's BE-4 engines). This potentially increases the amount of cargo one can carry from Earth to Mars as one no longer needs to bring hydrogen (for the Sabatier process for making methane) from Earth for the return trip back to Earth
- withinboredom 5y agoThat sounds like a ridiculous waste of such a scarce resource.
- vermilingua 5y agoWhy? This is one of the only economic advantages for settling mars; serving as a lower-g refueling station.
- withinboredom 5y agoUnless the water is replenished somehow, sending it all off-planet would mean no one could settle Mars.
- perl4ever 5y agoHow much water do you think is on Mars?
- eunoia 5y agoRefueling for what? The realities of orbital dynamics mean that Mars isn’t a convenient stopping place on the way to say, the outer solar system. I don’t have the numbers in my head but the delta-v requirements to intercept, match velocity and land negate any potential refueling benefit in my understanding. (Not to mention the added complexity vs a straight shot, this is a lot to pull off even in a sim like KSP) You might be able to make an argument for refueling bases on Mar’s tiny moons with their negligible gravity wells for Martian missions themselves but that’s about all I can see. What am I missing?