This is one of those very basic yet simple questions that needed tobe answered. That the answer turns out to be unconditional is abonus. We can grow plants happily in space. We all expected thatdoing so would become both necessary and doable. Now we know it isdoable.
We will soon be considering how to do the engineering as our accessto space gets serious and expansion begins in earnest. Bubbles onthe moon are particularly attractive. I wonder if it may be possibleto produce an active cellular structure of hexagonal units framingwater filled bubbles that also contain living algae to assist infiltering the incoming radiation from the sun. The plumbing would bea challenge of course but not impossible.
Such a construct would provide excellent living space inside forhumanity. It will still be much easier to operate underground with amile of rock providing protection to the dome.
Plants Grow FineWithout Gravity
New finding boosts theprospect of growing crops in space or on other planets.
James Owen
for NationalGeographic News
Published December 7,2012
http://news.nationalgeographic.com/news/2012/121207-plants-grow-space-station-science/
When researchers sentplants to the International Space Station in 2010, theflora wasn't meant to be decorative. Instead, the seeds of thesesmall, white flowers—called Arabidopsis thaliana—were thesubject of an experiment to study how plant roots developed in aweightless environment.
Gravity is animportant influence on root growth, but the scientists found thattheir space plants didn't need it to flourish. The research team fromthe University of Florida in Gainesville thinks this ability isrelated to a plant's inherent ability to orient itself as it grows.Seeds germinated on the International Space Station sprouted rootsthat behaved like they would on Earth—growing away from theseed to seek nutrients and water in exactly the same pattern observedwith gravity. (Related: "Beyond Gravity.")
Since the flowers wereorbiting some 220 miles (350 kilometers) above the Earth at the time,the NASA-funded experiment suggests that plants still retain anearthy instinct when they don't have gravity as a guide.
"The role ofgravity in plant growth and development in terrestrial environmentsis well understood," said plant geneticist and studyco-author Anna-Lisa Paul, with the University of Florida inGainesville.
"What is lesswell understood is how plants respond when you remove gravity."(See a video about plant growth.)
The new study revealedthat "features of plant growth we thought were a result ofgravity acting on plant cells and organs do not actually requiregravity," she added.
Paul and hercollaborator Robert Ferl, a plant biologist at the University ofFlorida in Gainesville, monitored their plants from the Kennedy SpaceCenter in Florida using images sent from the space station every sixhours.
Root Growth
Grown on anutrient-rich gel in clear petri plates, the space flowers showedfamiliar root growth patterns such as "skewing," whereroots slant progressively as they branch out.
"When we saw thefirst pictures come back from orbit and saw that we had most of theskewing phenomenon we were quite surprised," Paul said.
Researchers havealways thought that skewing was the result of gravity's effects onhow the root tip interacts with the surfaces it encounters as itgrows, she added. But Paul and Ferl suspect that in the absence ofgravity, other cues take over that enable the plant to direct itsroots away from the seed and light-seeking shoot. Those cues couldinclude moisture, nutrients, and light avoidance.
"Bottom line isthat although plants 'know' that they are in a novel environment,they ultimately do just fine," Paul said.
The finding furtherboosts the prospect of cultivating food plants in space and,eventually, on other planets.
"There's reallyno impediment to growing plants in microgravity, such as on along-term mission to Mars, or in reduced-gravity environments such asin specialized greenhouses on Mars or the moon," Paul said.(Related: "Alien Trees Would Bloom Black on Worlds WithDouble Stars.")
The study findingsappear in the latest issue of the journal BMC Plant Biology.
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