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Science

Green Mars 11

Felonyboy writes "A New Zealand scientist has grown asparagus and potatoes for the first time in soil taken from Martian meteors. Click here for the full story."
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Green Mars

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  • As much as I love the prospect of veggie plantations on Mars, I wish we(humans) would get our act together and distribute the food on earth in a manner to feed all people. We already produce enough food to support the earth's population. It is just that much of it is throw out to keep prices up. Also, a lot of US farmland remains unused because of gov't subsidies.

    While I am ranting on this I might as well plug thehungersite.com [thehungersite.com]. They donate food when you click through to vendors and you can buy Tshirts from them. They also have other sites like thekidsaidssite.com [thekidsaidssite.com]
  • that on Dune, they also had 400-meter-long worms that ruled the desert. Maybe those are under the ice caps too...

    just becaue you read it somewhere doesn't mean it really happened.
  • My da' (an expat brit)calls mathematics maths sometimes.

    To me the use of the word maths sounds like an Englishman sounding well...English.

    See the Language is not called USish. (I do not use Americanish because that would be all the forms of English found in north and south America, including but not limited to Canadain English (9 or ten different types), Jamacian English ... Well you get the idea.)

    If it was called USish, Aussies Probbably would not use it,
  • ..anyone remembers the terraforming process descibed in 'dune'? first some 'veggies', then slowly an entire planet could be turned into a comfortable place for human beings..

    ..IF there was oxygen on Mars :)
  • As an Aussie that has never taken offence at the fact that speech and/or hearing impaired Americans insist on pronouncing 'Aussie' as 'Os-ie', not 'Oz-ie', I think I am obliged to point out that NO dictionary lists veggies as a word (and yes, this does include Websters, or at least my copy). On the otherhand, my copy of the Macquarie Dictionary does infact recognise vegies.... admittedly with a 'col.' tag attached
  • well another big problem is getting to Mars in the first place. months of radiation and weightlessness (loss of bone mass from that). Mars' atmosphere may shield colonists, but there's no atmosphere on the long trek. we can hypothesize all kinds of things, but right now it looks bleak for going beyond the moon.

    but I want to go; to believe at least that someone sometime will get "out there."

    • Lack of sunlight.

      Mars is (very roughly) twice as far from the sun as the Earth. It gets one quarter as much sunlight.

    Mars orbits at about 1.4 AU from Sol, and gets about half as much sunlight. It also has a lot less atmosphere to scatter that incoming light before it reaches the surface (Earth's albedo is what, about 0.5?). Plenty of plants do just fine in partial shade. Or you could just use mirrors to put more light onto the plants.
    • Unshielded sunlight.

      Our atmosphere screens out a lot of the UV and other nastiness produced by the sun. The martian atmosphere won't (it's far too thin). Ionizing radiation (UV and other) will damage the plants' health more rapidly than on Earth.

    Since you need a greenhouse anyway, you use a material which filters the problematic wavelengths. Soda glass does a nice job on UV, for example.

    "
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  • And in the article, they even take into account that the atmosphere and temperature for the crops will have to be controlled, even if the soil can be used as it.

    But what about taking care of the atmosphere for the colonists, if they're all eating asparagus? I mean, asparagus is tasty and nutritious, but what about the `side effects' [boston.com]? If asparagus is a staple of Martian colonists, will they all get used to the smell, or will it require more heavy-duty filtering equipment to remove the odor?

    I wonder if perhaps foods that don't have the kind of `side effects' [webtv.net] asparagus has should be considered first? Beans/legumes may be inevitable, since the colonists will need protein and only vegetarian diets will be feasible, but the side effects of legumes can be kept under control with Beano [beano.net]. To the best of my knowledge, no similar remedy exists for the side effects of asparagus.

  • 1) Most colonization theories start with the assumption that there will be enough permafrost water close enough to the surface; if it isn't, there of course is a very serious problem

    2) Experiments have already been done showing that plants can be grown in a greenhouse with an atmosphere the pressure of that on the surface of Mars. For heat purposes a greenhouse will be necessary, of course.

    3) The same experiments that dealt with the pressure showed that you can get by with a mostly-CO2 atmosphere. Water vapor will have to be higher, but if you have the water you need in the first place, it won't be a problem.

    4) It'll be a problem when the colonies get big enough. In the early stages, they'll have to import some fertilizer to supplement waste recycling along with everything else that has to be imported from Earth.

    5) Nope, they won't grow as well as they would on Earth, but the plants can get by.

    6) Actually, the Martian atmosphere is pretty decent when it comes to screening out UV and other ionizing radiation, in part because you're already starting at 1/4 intensity. The greenhouse will also help, with the result that the radiation really won't be important.
  • by Christopher Thomas ( 11717 ) on Tuesday December 26, 2000 @08:37PM (#1404273)
    While interesting for a sound-bite, this experiment doesn't prove a whole lot about growing plants on Mars.

    Soil is pretty much inert. It's there to keep the plant from falling over. If you're lucky, you'll get soil with good water retention/drainage capabilities. However, this isn't exactly hard to come by or hard to produce yourself. While at any given time, soil will have nutrients and so forth in it, these cycle through fairly quickly - you have to keep adding them back, by using natural or artificial fertilizer.

    The main problems with growing plants on Mars are, in order:

    • Lack of water.

      No water, no plants. Water provides hydrogen for hydrocarbon synthesis. We simply don't know whether there's much water present on Mars. There are trace amounts in the atmosphere and ice caps, but we'll need more than trace amounts for agriculture. There may or may not be ice deposits beneath the planet's surface.

    • Air Pressure.

      Anything growing on Mars would have to be in a pressurized greenhouse. The air is far too thin to support life otherwise (low throughput by weight and very low boiling point of water at Martian densities (if liquid water can exist at all)).

    • Mostly-CO2 atmosphere

      Most plants do not grow in an atmosphere of pure CO2. You'd have to fiddle with the atmosphere composition inside your pressurized greenhouse, which will take a fair bit of startup effort (it may be self-sustaining once plants are growing).

    • Lack of nitrogen, phosphorus, and potassium.

      These are the primary nutrients supplied by fertilizer. You're going to have to make sure that there are minerals bearing all of these within easy reach of any large-scale agriculture, and you're going to have to have the industry to process them into fertilizer. Appropriate minerals may or may not show up on orbital surveys (depends on the geology). I have no idea how common these minerals are. Common or not, industry is expensive.

    • Lack of sunlight.

      Mars is (very roughly) twice as far from the sun as the Earth. It gets one quarter as much sunlight. While some plants will grow under these conditions, they won't grow as well as they would on Earth.

    • Unshielded sunlight.

      Our atmosphere screens out a lot of the UV and other nastiness produced by the sun. The martian atmosphere won't (it's far too thin). Ionizing radiation (UV and other) will damage the plants' health more rapidly than on Earth.



    While these issues are all tractable, none of them are addressed by the article. Thus, I have trouble taking the article seriously.
  • by tesserae ( 156984 ) on Tuesday December 26, 2000 @05:33AM (#1404274)
    At the moment pieces of one of those martian meteorites, Dar al Gani 476, are being commercially sold for around $300 a gram [meteorite.com] (search for "DaG476" in the page)...

    I'm a farm boy; I can assure you that asparagus and potato plants aren't exactly tiny. If this guy grew asparagus and potatoes in this soil, he either had a huge budget or he didn't grow the plants very large. Matter of fact, the meteorites themselves almost certainly didn't weigh more than a few pounds each -- most of 'em are pretty small. And I doubt that the owners would allow someone to use the whole thing up for a couple of plants, and even if he did he wouldn't grow either crop to maturity in a pound or two of soil!

    My guess is that he grew only sprouts and compared a few days growth, using a few grams of material. The only other way to manage it would be to use the samples to prepare a larger quantity of chemically-similar soil, and grow the test plants in that, but the story doesn't indicate that at all. Too bad there isn't a link to the research paper.

    ---

"Sometimes insanity is the only alternative" -- button at a Science Fiction convention.

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