quarta-feira, 31 de julho de 2013

Gold medals at 2014 Winter Olympics in Sochi to contain piece of meteorite: Video

Gold medal winners at next year’s Winter Olympics in Sochi, Russia could have an extra special glow about them, especially if they happen to win one on February 15.

To mark the one-year anniversary of a meteorite crashing down to earth in Chelyabinsk in the southern part of the country on February 15, 2013, the 7 gold medals won that day will feature a piece of the space rock.

The meteor strike, which resulted in many buildings being damaged and hundreds of Russian’s being injured, was the largest recorded for over a century.

Alexei Betekhtin, culture minister for the Chelyabinsk region said: ‘We will hand out our medals to all the athletes who win gold on that day, because both the meteorite strike and the Olympic Games are global events.’

The seven medal events taking place that day include men’s speedskating, ski jumping and the skeleton.

The medals will not be the only space related item at the Games, Russia will also launch a special Olympic torch into the atmosphere where it will be taken on a space walk on November 9.

Source: metro.co.uk

terça-feira, 23 de julho de 2013

Artist Wants to Launch Meteorite Back Into Space

An artist working with a 4.5-billion-year-old meteorite wants to send it back to space.

Katie Paterson has been using a large iron meteorite from Argentina in one of her installations titled "Campo del Cielo, Field of the Sky." But in 2014, she'll be ready to send a small piece of it back into outer space aboard an unmanned European Space Agency (ESA) cargo-carrying spacecraft bound for the International Space Station.

"By sending it back to space, I hope to fire the imaginations of students, youth — anyone, really — and foster a discussion on our relation with the wider universe," Paterson said in a statement.

The space rock used by Paterson in her installation was re-forged into a version of itself. Paterson crafted a mold of the meteorite and melted it down. She then poured the molten rock into the mold and allowed it to cool and harden back into its original shape.

"The iron, metal and dust inside have been reformed, and the layers of its cosmic life span — the intermixing of space and time, the billions of years of pressure and change — have become collapsed, transformed and then, by the hand of human technology, renewed," Paterson said.

The meteorite itself comes from a group of iron space rocks known as the Campo del Cielo meteorites found in Buenos Aires, Argentina. The site is home to at least 26 craters estimated to be about 4,000 to 5,000 years old, ESA officials said.

ESA officials will assess if the small piece of the meteorite qualifies for flight, and if it passes those tests, it will be sent into space aboard the European cargo vessel in 2014.

"I hope this helps inspire people everywhere to think about the really big questions: the origin of life, the natural history of our solar system and home planet, and our relationship with time, both geological and cosmic," Detlef Koschny, who is responsible for near-Earth object activities at ESA's Space Situational Awareness office, said in a statement. "These are important questions, and space exploration, together with art, are helping us answer them."

Paterson will speak at the Turner Contemporary gallery in the U.K. on July 30.

Source: space.com

quinta-feira, 18 de julho de 2013

Earth's Gold Came from Colliding Dead Stars

We value gold for many reasons: its beauty, its usefulness as jewelry, and its rarity. Gold is rare on Earth in part because it's also rare in the universe. Unlike elements like carbon or iron, it cannot be created within a star. Instead, it must be born in a more cataclysmic event -- like one that occurred last month known as a short gamma-ray burst (GRB). Observations of this GRB provide evidence that it resulted from the collision of two neutron stars -- the dead cores of stars that previously exploded as supernovae. Moreover, a unique glow that persisted for days at the GRB location potentially signifies the creation of substantial amounts of heavy elements -- including gold.

"We estimate that the amount of gold produced and ejected during the merger of the two neutron stars may be as large as 10 moon masses -- quite a lot of bling!" says lead author Edo Berger of the Harvard-Smithsonian Center for Astrophysics (CfA).

A gamma-ray burst is a flash of high-energy light (gamma rays) from an extremely energetic explosion. Most are found in the distant universe. Berger and his colleagues studied GRB 130603B which, at a distance of 3.9 billion light-years from Earth, is one of the nearest bursts seen to date.

Gamma-ray bursts come in two varieties -- long and short -- depending on how long the flash of gamma rays lasts. GRB 130603B, detected by NASA's Swift satellite on June 3rd, lasted for less than two-tenths of a second.

Although the gamma rays disappeared quickly, GRB 130603B also displayed a slowly fading glow dominated by infrared light. Its brightness and behavior didn't match a typical "afterglow," which is created when a high-speed jet of particles slams into the surrounding environment.

Instead, the glow behaved like it came from exotic radioactive elements. The neutron-rich material ejected by colliding neutron stars can generate such elements, which then undergo radioactive decay, emitting a glow that's dominated by infrared light -- exactly what the team observed.

"We've been looking for a 'smoking gun' to link a short gamma-ray burst with a neutron star collision. The radioactive glow from GRB 130603B may be that smoking gun," explains Wen-fai Fong, a graduate student at the CfA and a co-author of the paper.

The team calculates that about one-hundredth of a solar mass of material was ejected by the gamma-ray burst, some of which was gold. By combining the estimated gold produced by a single short GRB with the number of such explosions that have occurred over the age of the universe, all the gold in the cosmos might have come from gamma-ray bursts.

"To paraphrase Carl Sagan, we are all star stuff, and our jewelry is colliding-star stuff," says Berger.

Source: sciencedaily.com

sexta-feira, 12 de julho de 2013

Russian Chelyabinsk meteorite pieces go under microscope

Scientists have released microscopic images of fragments of the meteorite that hit central Russia in February.

A team from the Ural Federal University was able to analyse some of the dozens of samples as soon as they were found.

But the technique they used allowed them to assess the rock's chemical make-up at the microscopic level even as they snapped pictures of the fragments.

This will provide extra information on the space rock's formation and journey.

The fragments represent just a small portion of the remains of the 17m-diameter body that struck the Earth's atmosphere in a spectacular trail of light over the city of Chelyabinsk.

The team, led by Urals Federal University's Viktor Grokhovsky, determined right away that the overall chemistry of the meteorite was a familiar "chondrite".

"The fragments contain a standard number of minerals, including olivine, pyroxene, troilite and kamacite. These minerals that can be discovered only in outer space confirm the fragments' extraterrestrial nature," he told the Voice of Russia at the time.

But far more information was in the offing.

The team was using a scanning electron microscope, which fires a beam of electrons focused onto a tiny part of a sample, scanning around to see how the electrons are deflected and thereby building up a detailed picture of the sample's nanometre-scale bumps and valleys.

But that process causes the emission of a small amount of X-ray radiation - with the exact energy of the X-rays corresponding to the chemical element present in the focus of the electron beam.

This is where a silicon drift detector comes in - harvesting these X-rays and determining their energy. The result is a series of what are called X-ray maps - pictures of the same sample showing the presence and quantity of different elements.

It is this understanding of the minerals at a microscopic level that goes far beyond simply telling us what the meteorite is made of, said Simon Burgess of Oxford Instruments, which made the X-max silicon drift detector used by the team.

"For the researchers who are looking at this meteorite, it's going to be telling them information about which (mineral) phase is associated with which," he told BBC News.

"When they get into more detail beyond what the main chemistry of the meteorite is, they may be looking at processes in terms of how it formed, the temperature it formed at, what its history has been since its formation, possibly things about what happened to it during its impact with the Earth.

"A lot of that you cannot tell just by crushing it up and getting a 'bulk analysis'; you have to look at the chemistry of the individual parts and associations between the different minerals in the meteorite."

The X-max technology is in the running for the Royal Academy of Engineering's MacRobert Award, to be announced on Friday 19 July.

quarta-feira, 10 de julho de 2013

Iowa impact crater confirmed

Alexandria, VA -- Scientists have recently confirmed the existence of an impact crater buried below the town of Decorah, Iowa. Scientists first discovered what they thought resembled a crater in 2008, but now it has been corroborated by an airborne geophysical survey and hydrology surveys. Scientists estimate the diameter of the crater at 5.5 kilometers wide, nearly five times the size of the Barringer Meteor Crater in Arizona.

Based on the crater's size, scientists calculate that the region was likely hit by a meteorite roughly 250 meters in diameter about 500 million years ago, and could be related to other Midwestern impact craters. Statistically, similar-sized impactors could hit Earth's surface every 30,000 to 60,000 years.

Read further in the July issue of EARTH Magazine to learn more about the crater and what implications it might have for the availability of water and mineral resources:http://bit.ly/1dbqO43.

Don't miss the other great articles in the July issue of EARTH Magazine. Discover how the "X-Man" alga acquires its mutant abilities; learn more about the discovery of and legal battles over the Kennewick Man; and read one geologist's take on science and faith, all in this month's issue of EARTH, now available on the digital newsstand at http://www.earthmagazine.org/digital.

Source: American Geosciences Institute

Source: sciencecodex.com

terça-feira, 9 de julho de 2013

Cosmochemists Help Solve 135-Year-Old Meteorite Mystery

Scientists have provided a solution to a 135-year-old mystery in cosmochemistry, saying chondrules may have formed from high-pressure collisions in the early Solar System.

Chondrites are the largest class of meteorites, and scientists have wondered how numerous small, glassy spherules had become embedded within them. British mineralogist Henry Sorby first described these spherules in 1877 and suggested they may be “droplets of fiery rain” that somehow condensed out of the cloud of gas and dust that formed the Solar System 4.5 billion years ago.

However, Lawrence Grossman, professor in geophysical sciences at the University of Chicago, and colleagues have conducted research that better defines this 135-year-old thought.

The scientists reconstructed the sequence of materials that condenses from the solar nebula and concluded that a condensation process cannot account for chondrules. Grossman believes that chondrules derived from collisions between planetesimals, or bodies that gravitationally coalesced early in the history of the Solar System.

Cosmochemists believe that many types of chondrules had solid precursors. One problem is that high temperatures are needed to turn the condensed solid silicates into chondrule droplets. Another problem is that chondrules contain iron oxide. Iron can only enter the crystal structures of magnesium silicates when it is oxidized, and this is another process that requires very high temperatures.

“Impacts on icy planetesimals could have generated rapidly heated, relatively high-pressure, water-rich vapor plumes containing high concentrations of dust and droplets, environments favorable for formation of chondrules,” Grossman said.

During experiments, the scientists discovered a tiny pinch of sodium in the cores of the olivine cyrstals embedded within the chondrules. When olivine crystalizes form a liquid of chondrule composition at temperatures of 3,140 degrees Fahrenheit, most sodium remains in the liquid form if it doesn’t evaporate. The researchers found no more than 10 percent of the sodium ever evaporated from the solidifying chondrules.

Grossman and colleagues calculated the conditions required to prevent any degree of evaporation. They created calculations in terms of total pressure and dust enrichment in the solar nebula of gas and dust and determined that this couldn’t take place in the solar nebula. This led Grossman to the theory of planetesimal impacts.

“That’s where you get high dust enrichments. That’s where you can generate high pressures,” the researcher said.

The researchers have worked out the mineralogical calculations, and plan to collaborate with other scientists to see if they can recreate chondrule-forming conditions in the aftermath of planetesimal conditions. The scientists published their findings in the July issue of Geochimica et Cosmochimica Acta.

Source: Lee Rannals for redOrbit.com – Your Universe Online
Source: redorbit.com

domingo, 7 de julho de 2013

N. Michigan student spends week in NASA program

A Northern Michigan University student was among 35 undergraduates who spent a week in June at NASA's Johnson Space Centerin Houston.

"The week was just full of my mind being blown," elementary education major Kristen Bustrak of Brule, Wis., told The Mining Journal of Marquette (http://bit.ly/11ecUOA ) "All of these people (are) talking casually, 'Oh yeah, we're going to Mars.'"

She was among the students participating in the space program's Pre-Service Teacher Institute. Astronauts and rocket scientists show future teachers in the institute how to integrate NASA's work into school lessons.

Science, technology engineering and mathematics, also known as STEM, areas have been pushed in the last few years as more jobs require employees to be skilled in them.

"It's very important from such a young age to feel confident in STEM and be interested in STEM and feel, 'Hey, I can do this,'" Bustrak told the newspaper. "There's way too many students all around the world that feel, 'Oh I can't do that, it's too hard for me.' When you start at a young age, it instills confidence from the get go."

Bustrak said she speaks from experience.

"Science is hard for me, and in my application essay, I wrote about that, how there's always so many things to try and understand, and they don't click easy for me. I have to work really hard at it," Bustrak said. "But with the astronauts and the actual rocket scientists that I met, they were all so passionate about questioning and learning and discovering."

Bustrak will take what she learned to the classroom next semester when she begins student teaching in Green Bay, Wis.

"(I'll be) leading my students in discovering by asking questions, not just telling them information but asking them questions," she said."

And as a bonus, Bustrak became certified to handle moon rocks.

"We're all certified to handle lunar and meteorite samples, so when I'm a teacher, I'll be able to borrow lunar and meteorite samples from NASA and bring them to my classroom," she said.


Information from: The Mining Journal, http://www.miningjournal.net

Source: seattlepi.com