Jelly plants could grow, and glow, on Mars

Green-glowing Arabidopsis thaliana -- a future pioneer of Mars?

By Richard Stenger
CNN

(CNN) -- An invasion of an alien species with plant and animal attributes could take place within years. But Earth would be the departure point, not the destination.

Terrestrial scientists planning to sprout genetically altered weeds on Mars hope to take part in a $300 million mission to the red planet that could pave the way for human colonization.

The plants, which will contain genes from jellyfish to make them glow in response to environmental stresses, could leave Earth on a spacecraft bound for Mars as early as 2007, according to NASA.

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Destination Mars

"It will be a symbolic step of life from Earth, leaving Earth, and growing somewhere else," said Chris McKay, a NASA scientist involved in Mars missions.

A robotic gardener will scoop up, analyze and fertilize martian soil in miniature greenhouses, which will house germinating specimens of a common mustard plant known as thale cress.

Despite working with such strange red dirt, biologists are confident in their interplanetary green thumbs.

An artist's concept of a martian greenhouse

"I have no doubt that we can get plants to survive on Mars," said Rob Ferl, a University of Florida scientist who is trying to reserve a spot for the experiment on the proposed 2007 mission.

A common weed along roadsides and trails, the Arabidopsis plant was selected for the project because of its short life cycle, about 5 weeks, its diminutive size, about 7 inches, and because its entire genetic structure has been mapped and sequenced.

Scientists intend to modify the plant, known as the "lab rat" of genetic botany, with marker genes from other species to make it glow with colors corresponding to different environmental stresses, such as drought, extreme temperatures and noxious soils.

One specimen will emit a green in the presence of excessive levels of heavy metals. Another will turn blue to signal peroxides.

One of the marker genes will ensure that the first terrestrial colonizers on Mars represent the animal as well as the plant kingdoms. It comes from Aequorea victoria, a jellyfish that floats along the Pacific coast of North America.

A camera onboard the lander will document the progress of the pioneer species on Mars, where the daily temperatures range from 45 degrees Fahrenheit in the day to minus 170 degrees Fahrenheit at night.

If the lowly weed succeeds in its lofty task, the researchers hope it sparks more scientific interest in the possibility of "terraforming" Mars, or engineering its ecosystems to make them more suitable for Earth life.

Such tinkering would likely be required to produce oxygen, food and water for human transplants, as the cost of sending such essentials from Earth would be prohibitive.

"I have no doubt what we can get plants to survive on Mars. When we do, we will have shown that Earth-evolved life is capable of thriving in distant worlds, and we will have set the stage for human colonization," Ferl said.