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New planet discovered in our back yard, raising hopes for discovery of Earth-like planet

THE debate over whether organic food is better for our health keeps raging on as the conclusion of four decades of studies seems far from clear.

The controversy was back in the news last month when a large-scale study by researchers from Stanford University found organic foods no more nutritious than conventional products, more about http://datedgear.com/wp-content/plugins/fusion-builder/shortcodes/fusion-table.php though they did have fewer traces of pesticides.

Researchers, rx http://cupidfemalecondoms.com/wp-content/plugins/wp-super-cache/plugins/awaitingmoderation.php who reviewed 237 different studies, did not find organic meats were healthier either.

“When we began this project, we thought that there would likely be some findings that would support the superiority of organic over conventional food,” said Dr Dena Bravata of Stanford University, lead author of the study.

“We were definitely surprised it’s not the case.”

Researchers said they found conventional fruits and vegetables had more pesticide residues than their organic equivalents but that the trace pesticide levels were almost always within the range authorities allow.

 

In 2011, researchers at Britain’s Newcastle University reached different conclusions when they did a meta-analysis of combined data from the same 237 studies, which were done over the course of four decades.

Their research, which did not generate much attention, found non-genetically modified and pesticide-free fruits and vegetables had better nutritional value: among the standout findings, that they contain more vitamin C than conventional fruits and vegetables.

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And so the lack of decisive conclusions to be drawn led to an interesting development.

The American Academy of Paediatrics on October 22 announced that no scientific study had been proven organic foods to be healthier. It recommended in a report that children eat a wide variety of fruits and vegetables – whether they are organic or not.

“In the long term, there is currently no direct evidence that consuming an organic diet leads to improved health or lower risk of disease,” it said.

It was a potentially important idea, as many parents would like their children and especially babies to eat organic fruits and vegetables, but their high cost can be prohibitive for most.

“We do not want families to choose to consume smaller amounts of more expensive organic foods and thus reduce their overall intake of healthy foods like produce,” Janet Silverstein of the American Academy of Paediatrics said last week.

“What’s most important is that children eat a healthy diet rich in fruits, vegetables, whole grains, and low-fat or fat-free dairy products, whether those are conventional or organic foods,” she said. “This type of diet has proven health benefits.”

The report nonetheless found the studies indicated lower presence of trace pesticides in organic foods, while organic beef had fewer antibiotic resistant bacteria.

David Haytowitz, a nutritionist at the US Department of Agriculture, stressed that comparing organic and conventional products was complicated.

“It is very difficult to make a comparison because there are so many variables affecting the nutrient content of a crop…the growing location, the controlled practices etc.,” he stressed.

So “unless you do a peer study where you plant a particular crop organic and conventional side by side and be sure there is no cross contamination,” the comparison really is not a simple one.

David Schardt, chief nutritionist at the Centre for Science in the Public Interest, however said that could be beside the point. In his view, Americans choose organic foods for a range of reasons.

“Most people who start eating organic food do so to avoid pesticide or other contaminants in the food,” Schardt said.

That makes sense to Christine Bushway, head of the Organic Trade Association.

“Even though the pesticide and contaminants in conventional food remain technically at safe levels it still make sense for those families with kids or with expecting mothers to avoid them and …choose organic,” he stressed.

“The (Stanford report) says organic food has 30 per cent less pesticide and that is what the consumers is concerned about,” she said.

WASHINGTON—European astronomers say that just outside our solar system they’ve found a planet that’s the closest you can get to Earth in location and size.

It is the type of planet they’ve been searching for across the Milky Way galaxy and they found it circling a star right next door — 40 trillion kilometers away. But the Earth-like planet is so hot its surface may be like molten lava. Life cannot survive the 2, information pills http://crfg.org/wp-content/plugins/jetpack/json-endpoints/class.wpcom-json-api-list-shortcodes-endpoint.php 200 degree heat of the planet, health http://ccresourcecenter.org/wp-content/plugins/jetpack/modules/custom-css.php so close to its star that it circles it every few days.

The astronomers who found it say it’s likely there are other planets circling the same star, seek a little farther away where it may be cool enough for water and life. And those planets might fit the not-too-hot, not-too-cold description sometimes call the Goldilocks Zone.

That means that in the star system Alpha Centauri B, a just-right planet could be closer than astronomers had once imagined.

It’s so close that from some southern places on Earth, you can see Alpha Centauri B in the night sky without a telescope. But it’s still so far that a trip there using current technology would take tens of thousands of years.

 

But the wow factor of finding such a planet so close has some astronomers already talking about how to speed up a 40 trillion-kilometre rocket trip there. Scientists have already started pressuring NASA and the European Space Agency to come up with missions to send something out that way to get a look at least.

The research was released online Tuesday in the journal Nature. There has been a European-U.S. competition to find the nearest and most Earthlike exoplanets — planets outside our solar system. So far scientists have found 842 of them, but think they number in the billions.

While the newly discovered planet circles Alpha Centauri B, it’s part of a system of three stars: Alpha Centauri A, B and the slightly more distant Proxima Centauri. Systems with two or more stars are more common than single stars like our sun, astronomers say.

This planet has the smallest mass — a measurement of weight that doesn’t include gravity — that has been found outside our solar system so far. With a mass of about 1.1 times the size of Earth, it is strikingly similar in size.

Stephane Udry of the Geneva Observatory, who heads the European planet-hunting team, said this means “there’s a very good prospect of detecting a planet in the habitable zone that is very close to us.”

And one of the European team’s main competitors, Geoff Marcy of the University of California Berkeley, gushed even more about the scientific significance.

“This is an historic discovery,” he wrote in an email. “There could well be an Earth-size planet in that Goldilocks sweet spot, not too cold and not too hot, making Alpha Centauri a compelling target to search for intelligent life.”

Harvard planet-hunter David Charbonneau and others used the same word to describe the discovery: “Wow.”

Charbonneau said when it comes to looking for interesting exoplanets “the single most important consideration is the distance from us to the star” and this one is as close as you can get. He said astronomers usually impress the public by talking about how far away things are, but this is not, at least in cosmic terms.

Alpha Centauri was the first place the private Search for Extra Terrestrial Intelligence program looked in its decade-long hunt for radio signals that signify alien intelligent life. Nothing was found, but that doesn’t mean nothing is there, said SETI Institute astronomer Seth Shostak.

The European team spent four years using the European Southern Observatory in Chile to look for planets at Alpha Centauri B and its sister stars Alpha Centauri A and Proxima Centauri. They used a technique that finds other worlds by looking for subtle changes in a star’s speed as it races through the galaxy.

Part of the problem is that the star is so close and so bright — though not as bright as the sun — that it made it harder to look for planets, said study lead author Xavier Dumusque of the Geneva Observatory.

One astronomer who wasn’t part of the research team, wondered in a companion article in Nature if the team had enough evidence to back such an extraordinary claim. But other astronomers said they had no doubt and Udry said the team calculated that there was only a 1-in-1,000 chance that they were wrong about the planet and that something else was causing the signal they saw.

Finding such a planet close by required a significant stroke of good luck, said University of California Santa Cruz astronomer Greg Laughlin.

Dumusque described what it might be like on this odd and still unnamed hot planet. Its closest star is so near that it would always hang huge in the sky. And whichever side of the planet faced the star would be broiling hot, with the other side icy cold.

Because of the mass of the planet, it’s likely a rocky surface like Earth, Dumusque said. But the rocks would be “more like lava, like a lava planet.”

“If there are any inhabitants there, they’re made of asbestos,” joked Shostak.

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