Lifeboat Foundation

An unusual chunk in a meteorite may contain a surprising bit of space history, based on new research from Washington University in St. Louis.

Presolar grains—tiny bits of solid interstellar material formed before the sun was born—are sometimes found in primitive meteorites. But a new analysis reveals evidence of presolar grains in part of a meteorite where they are not expected to be found.

“What is surprising is the fact that presolar grains are present,” said Olga Pravdivtseva, research associate professor of physics in Arts & Sciences and lead author of a new paper in Nature Astronomy. “Following our current understanding of solar system formation, presolar grains could not survive in the environment where these inclusions are formed.”

Here on Earth, we pay quite a lot of attention to the sun. It’s visible to us, after all, and central to our lives. But it is only one of the billions of stars in our galaxy, the Milky Way. It’s also quite small compared to other stars – most are at least eight times more massive.

These massive stars influence the structure, shape and chemical content of a galaxy. And when they have exhausted their hydrogen gas fuel and die, they do so in an explosive event called a supernova. This explosion is sometimes so strong that it triggers the formation of new stars out of materials in the dead star’s surroundings.

But there’s an important gap in our knowledge: astronomers don’t yet fully understand how those original massive stars themselves are initially formed. So far, observations have only yielded some pieces of the puzzle.

To further shrink electronic devices and to lower energy consumption, the semiconductor industry is interested in using 2-D materials, but manufacturers need a quick and accurate method for detecting defects in these materials to determine if the material is suitable for device manufacture. Now a team of researchers has developed a technique to quickly and sensitively characterize defects in 2-D materials.

Two-dimensional materials are atomically thin, the most well-known being graphene, a single-atom-thick layer of carbon atoms.

“People have struggled to make these 2-D materials without defects,” said Mauricio Terrones, Verne M. Willaman Professor of Physics, Penn State. “That’s the ultimate goal. We want to have a 2-D material on a four-inch wafer with at least an acceptable number of defects, but you want to evaluate it in a quick way.”

While not as strong as concrete, the bricks could reduce the CO₂ footprint of a building, self-heal, and even reproduce.

[Photo: University of Colorado Boulder College of Engineering and Applied Science].

Concrete and steel come with massive emissions. So let’s ditch them and build towers out of wood. Yes, wood.

When it comes to building the interior of a spacecraft, engineers often prioritize function over aesthetics, focusing on materials and hardware that are both safe and effective for executing the vehicle’s intended mission. But some scientists say it’s time to consider another crucial factor when designing a spacecraft’s insides: how it will affect the behavior of the passengers?

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A Philippine city affected by heavy ashfall from the nearby Taal Volcano has started collecting ash to make bricks, providing needed building materials for post-disaster reconstruction in neighbouring towns.

Continue reading “Philippine city makes bricks from Taal Volcano ash for reconstruction work” »

Different kinds of materials can play different roles when it comes to controlling heat. If we want to keep our home warm in the depths of winter, insulating layers in our walls can help to lock it in. If we want to keep things cool, thermally conductive materials like those used in computer processors can help carry it away. But could one material have it both ways? A new breakthrough suggests that it could, made by a team of scientists who believe heat needn’t just be a one way street.

The research was carried out by scientists at the University of Bayreuth and the Max Planck Institute for Polymer Research, who sought to combine the thermally insulating properties of materials like polystyrene, with the thermally conductive properties of heavy metals often used to dissipate heat.

Their breakthrough boils down to a way of manipulating the way heat travels, which is through the oscillation of individual molecules that pass on their movement to neighboring molecules.

A team of researchers from the University of Washington has found evidence that the Earth’s atmosphere approximately 2.7 billion years ago might have been up to 70 percent carbon dioxide. In their paper published in the journal Science Advances, the group describes their study of micrometeorites and what they learned from them.

As scientists continue to study Earth’s past, they look for evidence of what environmental conditions might have been like in hopes of understanding how life arose. One important piece of the puzzle is the atmosphere. Scientists suspect that its ingredients were far different billions of years ago, but they have little in the way of evidence to prove it. In this new endeavor, the researchers looked to micrometeorites as a possible source of clues. Their thinking was that any material from space that made its way to the surface of the planet had to travel first through the atmosphere—and any material that travels through the atmosphere is highly influenced by its materials, largely due to the high temperatures of atmospheric entry.

Several years ago, researchers found a host of micrometeorites that had landed on Earth approximately 2.7 billion years ago, putting them squarely in the Archean Eon—the time during which it is believed life first appeared on Earth. Study of the micrometeorites showed that they contained high levels of iron along with wüstite. Wüstite forms when iron is exposed to oxygen, but not on the Earth’s surface. It must have been created as the grain-sized meteorites burned and fell through the Earth’s atmosphere. Intrigued by the finding, the researchers created a computer model to simulate the conditions that would lead to the creation of materials such as wüstite on a rock falling through the atmosphere.