quarta-feira, 29 de abril de 2015

Attention treasure-hunters! €10k pieces of meteorite fall in Ireland

An Irish person could be in for a cash windfall after pieces of meteorite worth up to €10,000 each fell from the skies at the weekend.

Hundreds of people witnessed a fireball streaking across the Irish skies at approximately 10.10pm on Sunday evening.

According to David Moore, editor of the Astronomy Ireland magazine, each piece of meteorite could fetch up to ten times the price of gold in the collectors' market.

At the current price of gold, this means that a piece of meteorite rock weighing approximately 28 grams could make the lucky person a cool €10,000.

It is believed that two meteorites land in Ireland every year, but they are rarely visible to the naked eye.

Astronomy Ireland have received hundreds of reports of the sighting, with coast guards in the south-west of the country getting mistaken reports of 'flares being released'.

Experts believe this meteorite, seen streaking from Kerry towards Donegal, could have been as large as a car while still whole.

"There is a chance some parts of this meteorite survive, and we think it may have fallen somewhere in the north of the country," Astronomy Ireland's David Moore told RTE Radio One's Morning Ireland as he appealed for people to share their stories of the sighting.

"We'd ask people to get in contact with us while it's still fresh in their mind. Check your CCTV cameras if you have them, a photographic report would be worth hundreds of eye witness reports," he said.

"The price of meteorites and what they're worth would come from the collectors and what they're prepared to pay," he continued.

"It is a big trade and Irish meteorites are very rare. It's a small island, this doesn't happen very often."

David recalled the last time a meteorite was recovered in Ireland in Loughlinbridge in Co Carlow in 1999.

"Pieces were found in north Co Carlow, the collector who bought some of them wanted to stay anonymous, but they were being bought for ten times the price of gold," Mr Moore said.

"However, we're not interested in the commercial value, we're interested in the fact that these are scientific specimens."

If people do go hunting in their local fields for the pieces of precious rock, Mr Moore advised them to look closely.

"The rocks might like they are nothing special," he said.

"The earth is effectively built up of billions of meteorites, but because they've been through the re-entry they'll be melted with a dark fusion crust.

"If they've been cracked open, they look like crystallised structures, some parts look like metal, other parts may look like coal. It would be like a burnt-looking rock looking out of place on the ground."

Mr Moore said Astronomy Ireland are seeking for people to fill out the report form on Astronomy.ie (click here).

Source: independent.ie/irish-news

segunda-feira, 27 de abril de 2015

Building blocks of the run-up to life recreated in space-like conditions

Researchers have reproduced a wide array of building blocks for life in a prebiotic scenario involving meteorites and the solar wind.

They began with formamide, a simple organic compound that's ubiquitous in the universe. Formamide has been detected in galactic centers, star-forming regions, interstellar space, as well as comets and satellites.
They then added meteorite powder as a catalyst, and irradiated the solution with high-energy proton beams to simulate the solar wind. They obtained a rich blend of complex biological molecules including amino acids, carboxylic acids, sugars, and nucleobases (the basic building blocks for DNA and RNA).
Among the products were also the nucleosides cytidine, uridine, adenosine, and thymidine, which are more advanced building blocks consisting of a nucleobase linked to a sugar molecule. Nucleosides are notoriously difficult to recreate under prebiotic conditions.
"We were very surprised to see those," says Raffaele Saladino of Tuscia University, Italy.
The ingredients for life have previously been recreated under a variety of possible terrestrial scenarios involving lightning, ultraviolet radiation,
hydrothermal vents, or meteorite impacts. The new findings expand the range of possibilities to prebiotic environments beyond the early Earth, including to the small, wandering bodies of our solar system.
The results were published this week in the Proceedings of the National Academy of Sciences.

The team had previously synthesized some of the building blocks (but no nucleosides) by subjecting formamide to very high temperatures, simulating conditions near volcanoes or upon meteorite impact on the early Earth.
By instead irradiating formamide with high-energy protons, they obtained a higher yield of amino acids and nucleobases, as well as other relevant biomolecules including the nucleosides.
"Proton chemistry goes one step farther than heat chemistry," says study co-author Ernesto Di Mauro of the University of Rome La Sapienza."Proton radiation turns out to be amazingly efficient."
He adds: "Carbon chemistry works the same anywhere in the universe, and every star produces solar wind. This tells us that life could well be universal."
Interestingly, the scenario produced a high quantity of precursors for both metabolic and genetic pathways (the carboxylic acids and nucleobases respectively.) An ongoing debate with the origin of life is whether metabolism or genetics emerged first. Here, the findings suggest that both processes could have emerged simultaneously.

Other findings have also suggested that meteorites may have seeded the ingredient for life on the early Earth, notably during the late heavy bombardment, a period when the inner planets were pummeled by frequent impacts about 4.1 to 3.8 billion years ago. In particular, some simple amino acids, sugars, and nucleobases have been found inside meteorites, albeit in very small proportions.
Here, the researchers wanted to go beyond the idea of meteorites as mere carriers of organic molecules.
They tested the catalytic properties of eleven meteorites belonging to the four major classes—iron, stony iron, chondrites, and achondrites—but first treated the rock powder to remove any trace of organics.
They found that the minerals within the meteorites were necessary to catalyze the synthesis of the molecules, with the stony iron, chondrite, and achondrite meteorites more active than the iron meteorites as a general trend. They also tested individual minerals present in the meteorites and found that the full powder was needed for full catalytic effect.
"Meteorites are not merely shuttles for organics, as suggests the common point of view," Saladino says. "They are also reactors that can synthesize biomolecules during their lives."

The findings come with an important caveat. "I'm extremely enthusiastic about this piece of work because they obtained much more than the nucleobases," says Steven Benner, an origin-of-life chemist at the Foundation for Applied Molecular Evolution at the Westheimer Institute in Gainesville, Fla.
"They combined formamide and rock chemistry and got so many building blocks—that's what makes this paper important." "But the catch is that the total mass of meteorite that's coming in after the Moon-forming event is negligible," he adds.
"You can't rely on the Late Heavy Bombardment to bring you much in terms of organics. Besides, that amount of carbon is negligible compared to what's here on Earth already."
Indeed, formamide, the starting molecule in their experiment, is readily made from hydrogen cyanide and water — two compounds that were abundant on the early Earth. "My view is that we have to solve the problem with what's here on Earth before we go looking at meteorites," Benner said, "just because of the amount of material that's coming in."

NASA's Astrobiology Magazine at astrobio.net

Fonte: bangaloremirror.com

quinta-feira, 9 de abril de 2015

NASA: We’ll find alien life in 10 to 20 years

Are we alone in the universe? Top NASA scientists say the answer is almost certainly “no.”

“I believe we are going to have strong indications of life beyond Earth in the next decade and definitive evidence in the next 10 to 20 years,” Ellen Stofan, chief scientist for the National Aeronautics and Space Administration, said at a public panel Tuesday in Washington.

“We know where to look, we know how to look, and in most cases we have the technology,” she said.

Jeffery Newmark, interim director of heliophysics at the agency put it this way: “It’s definitely not an if, it’s a when.”

However, if visions of alien invasions are dancing in your head, you can let those go.

“We are not talking about little green men,” Stofan said. “We are talking about little microbes.”

Over the course of an hourlong presentation, NASA leaders described a flurry of recent discoveries that suggest we are closer than ever to figuring out where we might find life in the solar system and beyond.

For example, Jim Green, director of planetary science at NASA, cited a study that analyzed the atmosphere above Mars’ polar ice caps and suggests that 50 percent of the planet’s northern hemisphere once had oceans up to a mile deep, and that it had that water for a long period of time — up to 1.2 billion years.

“We think that long period of time is necessary for life to get more complex,” Stofan said.

She added that getting human field geologists and astrobiologists on Mars would greatly improve the chances of finding fossils of past life on our nearest planetary neighbor.

Green also described another recent study that used measurements of aurora on Jupiter’s moon Ganymede to prove it has a large liquid ocean beneath its icy crust.

The findings suggest that previous ideas about where to find “habitable zones” may have been too limited. (A body considered to in a habitable zone is not too hot or too cold for liquid water to exist on its surface.)

“We now recognize that habitable zones are not just around stars, they can be around giant planets too,” Green said. “We are finding out the solar system is really a soggy place.”

He also talked NASA’s plans for a mission to Europa, another moon of Jupiter with an icy ocean.

“I don’t know what we are going to find there,” he said.

Newmark described how NASA is learning more about the role of Earth’s magnetic field in protecting our planet’s water and atmosphere from being blown away by the solar wind, thereby playing a role in the ability for life to develop.

“Mars does not have a significant magnetic field, so it lets the wind strip away the water and atmosphere,” he said.

Paul Hertz, director of astrophysics at NASA, talked about how future telescopes already in the works will help scientists scan the atmospheres of large rocky planets around distant stars for chemical markers of life.

“We are not just studying water and habitability in our solar system, but also looking for it in planets around other stars,” he said.

NASA associate administrator John Grunsfeld, said part of what excites him most about the search for life beyond our planet is to see what that life looks like.

“Once we get beyond Mars, which formed from the same stuff as Earth, the likelihood that life is similar to what we find on this planet is very low,” he said.

Grunsfeld said he believes that life beyond Earth will be found by the next generation of scientists and space explorers, but Green said he hopes it is sooner than that.

“The science community is making enormous progress,” he said. “And I’ve told my team I’m planning to be the director of planetary science when we discover life in the solar system."

Source: msn.com/en-us/news/technology/nasa