Tag: Diamonds

Puzzling Cosmic Glow Is Caused by Diamond Dust Glamming Up Stars

Diamond dust is responsible for a mysterious glow emanating from certain regions of the Milky Way galaxy, a new study reports.

Astronomers have long known that some type of very small, rapidly spinning particle is throwing off this faint light, which is known as anomalous microwave emission (AME). But they couldn’t identify the exact culprit — until now.

In the new study, researchers used the Green Bank Telescope in West Virginia and the Australia Telescope Compact Array to search for AME light in 14 newborn star systems across the Milky Way.

They spotted the emissions in three of these systems, coming from the planet-forming disks of dust and gas swirling around the stars.

This is the first clear detection of anomalous microwave emission coming from protoplanetary disks,” study co-author David Frayer, an astronomer with the Green Bank Observatory, said in a statement.




The study team also detected the unique infrared-light signatures of nanodiamonds — carbon crystals far smaller than a grain of sand — in these same three systems, and nowhere else.

In fact, these [signatures] are so rare, no other young stars have the confirmed infrared imprint,” study lead author Jane Greaves, an astronomer at Cardiff University in Wales, said in the same statement.

The researchers don’t think this is a coincidence.

One to 2 percent of the total carbon in these protoplanetary disks has been incorporated into nanodiamonds, according to the team’s estimates.

Another leading AME-source candidate, a family of organic molecules known as polycyclic aromatic hydrocarbons (PAHs), doesn’t hold up under scrutiny, the researchers said.

The infrared signature of PAHs has been identified in multiple young star systems that lack an AME glow, they noted.

The new results could help astronomers better understand the universe’s early days, study team members said.

Scientists think the universe expanded far faster than the speed of light shortly after the Big Bang, in a brief period of “cosmic inflation.

If this did indeed happen, it should have left a potentially detectable imprint — an odd polarization of the cosmic microwave background, the ancient light left over from the Big Bang.

The new study provides “good news for those who study polarization of the cosmic microwave background, since the signal from spinning nanodiamonds would be weakly polarized at best,” said co-author Brian Mason, an astronomer at the National Radio Astronomy Observatory in Charlottesville, Virgina.

This means that astronomers can now make better models of the foreground microwave light from our galaxy, which must be removed to study the distant afterglow of the Big Bang,” Mason added.

Please like, share and tweet this article.

Pass it on: Popular Science

 

‘Diamonds From The Sky’ Approach Turns CO2 Into Valuable Products

Finding a technology to shift carbon dioxide (CO2), the most abundant anthropogenic greenhouse gas, from a climate change problem to a valuable commodity has long been a dream of many scientists and government officials.

Now, a team of chemists says they have developed a technology to economically convert atmospheric COdirectly into highly valued carbon nanofibers for industrial and consumer products.

The team will present brand-new research on this new CO2 capture and utilization technology at the 250th National Meeting & Exposition of the American Chemical Society (ACS). ACS is the world’s largest scientific society.

The national meeting, which takes place here through Thursday, features more than 9,000 presentations on a wide range of science topics.




We have found a way to use atmospheric CO2 to produce high-yield carbon nanofibers,” says Stuart Licht, Ph.D., who leads a research team at George Washington University.

“Such nanofibers are used to make strong carbon composites, such as those used in the Boeing Dreamliner, as well as in high-end sports equipment, wind turbine blades and a host of other products.”

Previously, the researchers had made fertilizer and cement without emitting CO2, which they reported.

Now, the team, which includes postdoctoral fellow Jiawen Ren, Ph.D., and graduate student Jessica Stuart, says their research could shift CO2from a global-warming problem to a feed stock for the manufacture of in-demand carbon nanofibers.

Licht calls his approach “diamonds from the sky.”

That refers to carbon being the material that diamonds are made of, and also hints at the high value of the products, such as the carbon nanofibers that can be made from atmospheric carbon and oxygen.

Because of its efficiency, this low-energy process can be run using only a few volts of electricity, sunlight and a whole lot of carbon dioxide.

At its root, the system uses electrolytic syntheses to make the nanofibers.

Please like, share and tweet this article.

Pass it on: Popular Science

Rare Blue Diamond Found In South Africa’s Cullinan Mine

The 29.6-carat stone was recovered by Petra Diamonds at its Cullinan mine, about 40km (25 miles) north-east of Pretoria.

This stone is one of the most exceptional stones recovered at Cullinan during Petra’s operation of the mine,” the company said.

Petra unearthed a 25.5 carat blue diamond which sold for $16.9m (£10.3m) in 2013. The latest discovery is also expected to sell for a high price.




The stone is an outstanding vivid blue with extraordinary saturation, tone and clarity, and has the potential to yield a polished stone of great value and importance,” Petra said in a statement on Tuesday.

Cullinan mine has produced hundreds of large stones and is famed for its production of blue diamonds – among the rarest and most highly coveted of all diamonds.

The mine was acquired in 2008 by Petra Diamonds, which also operates in Botswana and Tanzania.

A similar 26.6-carat blue rough diamond discovered by the company in May 2009 was cut into a near perfect stone and fetched just under $10m at a Sotheby’s auction.

The Cullinan mine is famed for the production of blue diamonds

Another deep-blue diamond from Cullinan was auctioned for $10.8m in 2012 and set a world record for the value per carat.

The largest ever rough gem diamond was discovered at the Cullinan mine in 1905 and was presented to the British monarch Edward VII.

The 3,106-carat stone was then cut, with two of the principal diamonds forming part of the British crown jewels – the 530-carat First Star of Africa and the Second Star of Africa at 317 carats.

Please like, share and tweet this article.

Pass it on: Popular Science

Diamonds Probably Don’t Crystallize In The Atmosphere Of Uranus

A new study finds that diamonds probably don’t crystallize in the atmospheres of planets such as Uranus and Neptune.

The conclusion is contrary to recent speculation that small diamonds would spontaneously form in carbon rich layers of the gas giant planets. White dwarf stars, according to the study, are veritable diamond factories.

Physicists at the Universtiet van Amsterdam and the FOM Institute for Atomic and Molecular Physics in the Netherlands performed a numerical analysis showing that at the temperatures and pressures in gas giant planets like Uranus.

Arrangements of carbon atoms would be much more suitable for creating tiny bits of graphite rather than diamond.




In white dwarfs, on the other hand, the simulation shows that the conditions would cause the carbon atoms to line up in configurations that are much more amenable for diamond crystallization.

The conclusion is consistent with the 2004 discovery of a cooling white dwarf star that appears to have a solid diamond core 4000 kilometers across.

Although diamond formation in the atmospheres of gas giants is not strictly impossible, the Dutch physicists say that the odds are exceedingly slim that a diamond could have formed under the conditions that exist in Uranus in the entire lifetime of the universe.

Please like, share and tweet this article.

Pass it on: Popular Science