Martian soil has nutrients needed to grow plants

Stick an asparagus plant in a pot full of Martian soil, and the asparagus might grow happily, scientists announced Thursday.

An experiment on the Phoenix Mars lander showed the dirt on the planet's northern arctic plains to be alkaline, though not fiercely alkaline, and full of the mineral nutrients that a plant would need.

"We're flabbergasted by this data," said Sam Kounaves, the lead scientist on the wet chemistry experiment for the Phoenix spacecraft, which landed on Mars on May 25. "We've found nutrients that could support life."

A sample of soil was delivered to the lab by the lander's nearly 8 foot long robotic arm and mixed with water brought from Earth. Analysis shows that the soil is alkaline, with a pH between 8 and 9, Kounaves said.

That's too alkaline for strawberries, but not for other crops.

The finding came as something of a surprise, at least to the many scientists who have argued that Martian soil was likely too acidic to support life.

The test also turned up magnesium, sodium, potassium and chloride, all of which are useful in organic processes.

But the test did not turn up what the $420 million mission was sent to find: complex organics that would indicate Mars once was, or still might be, habitable.

And any futuristic plan to plant crops there would have require them to be grown underground, because the Martian atmosphere lets in too much of the sun's destructive ultraviolet rays.

The scientific team from the University of Arizona and the Jet Propulsion Laboratory in La Canada Flintridge, Calif., emphasized that these results represent an analysis of a small piece of a large Martian landscape.

Still, the scientists said Thursday in a briefing, the early results are encouraging.

"There's nothing about [the soil] that would preclude life," Kounaves said.

FOOD CARTS GO GREEN IN N.Y.C.

Street vendors offer a cornucopia of calorie-packed temptations on almost every corner in New York. But what if you're looking for a crisp apple? Or a crunchy carrot?

Good luck.

Now, however, in an effort to get New Yorkers to eat better, the city is preparing to issue licenses for 500 food carts that will be allowed to sell only fresh fruit and vegetables. The carts, which are expected to start appearing later this summer, are restricted to low-income areas that have the fewest sources of fresh produce in the city.

The move comes in the wake of the city's indoor smoking ban and its campaign to get restaurants to eliminate the use of trans fats and a requirement that menus list calories.

"While the hot dog cart may be a cherished New York institution -- and I say that with some authority -- with this legislation, we aim to make the 'Green Cart' just as ubiquitous and loved," said Mayor Michael Bloomberg.

BUZZ AT CAPITOL: HELP SAVE OUR BEES

A record 36 percent of U.S. commercial bee colonies have been lost to mysterious causes so far this year, and worse may be yet to come, experts told a congressional panel Thursday.

The year's bee colony losses are about twice the usual seen following a typical winter, scientists warn. Despite ambitious new research efforts, the causes remain a mystery.

"We need results," pleaded California beekeeper Steve Godlin. "We need a unified effort by all."

Researchers from the Department of Agriculture and other agencies told lawmakers that they have a hunch that the problem could be related to a parasite spreading a virus among the six-legged insects.

The so-called colony collapse disorder is characterized by a sudden decline in a bee colony's population and the inexplicable absence of dead bees. First reported in 2006, the disorder was blamed for the 31 percent decline in bee colonies last year.

"What seemed to be an aberration has unfortunately turned into a full-fledged crisis," said Rep. Dennis Cardoza, D-Calif.

PLANTS SEEK TO ESCAPE THE HEAT

Faced with global warming, plants are heading for the hills.

A study of 171 forest species in Western Europe shows that most of them are shifting their favored locations to higher, cooler spots.

For the first time, research can show the "fingerprints of climate change" in the distribution of plants by altitude, and not only in sensitive ecosystems, said Jonathan Lenoir of AgroParisTech, the agricultural branch of the Paris Institute of Technology. Researchers led by Lenoir reported their results in today's edition of the journal Science.

Quickest to relocate were plants such as herbs, ferns and mosses with shorter life spans and faster reproduction cycles, the researchers said. Not so fleeting were large woody plants that reproduce more slowly and thus are more threatened by climate change, Lenoir said.

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