It brings a new meaning to the phrase organic chemistry. Chemists have discovered that fungi can naturally absorb microscopic metal particles into their flesh in a way that could see metallic fungus used as catalysts or disinfectants.
Industrial catalysts often rely on processes that happen on the surface of metals, so tiny nanoparticles of catalyst with large surface-area-to-volume ratios are particularly effective. But such particles are only effective if they are prevented from clumping together using a chemical solution, which makes it difficult to separate the catalyst from the products of a reaction.
Science & Technology
What began as a farfetched idea 50 years ago, drilling a hole into the sea floor from a floating vessel, was successful and soon opened up an exciting new era of ocean exploration which continues today.
The Ocean Drilling Program, by obtaining long cores of sediment and ancient rock from the floors of the world's oceans, has been making discoveries that have challenged old ideas and brought entirely new concepts to light. Drill ships have evolved and become more sophisticated, enabling scientists to drill in greater water depths and progressively deeper into the sea floor.
Hundreds of cores have been obtained over the past four decades, in water more than 4 miles deep and penetrating as deep as 6,000 feet into the ocean floor. Each voyage is normally two months long and typically involves dozens of scientists from universities around the world. The United States has provided much of the scientific leadership over the years, and scientists at UC Santa Cruz have played major roles in organizing and leading the scientific drilling program.
What have we discovered as these voyages have continued to probe the deep ocean floor? Drilling in the Caribbean uncovered proof that an asteroid struck near the Yucatan peninsula 65 million years ago, and not only led to the extinction of 60 to 70 percent of all plant and animals species on earth, including 90 percent of all of the plankton in the ocean, but also led to the die-out of the dinosaurs.
The Ocean Drilling Program, by obtaining long cores of sediment and ancient rock from the floors of the world's oceans, has been making discoveries that have challenged old ideas and brought entirely new concepts to light. Drill ships have evolved and become more sophisticated, enabling scientists to drill in greater water depths and progressively deeper into the sea floor.
Hundreds of cores have been obtained over the past four decades, in water more than 4 miles deep and penetrating as deep as 6,000 feet into the ocean floor. Each voyage is normally two months long and typically involves dozens of scientists from universities around the world. The United States has provided much of the scientific leadership over the years, and scientists at UC Santa Cruz have played major roles in organizing and leading the scientific drilling program.
What have we discovered as these voyages have continued to probe the deep ocean floor? Drilling in the Caribbean uncovered proof that an asteroid struck near the Yucatan peninsula 65 million years ago, and not only led to the extinction of 60 to 70 percent of all plant and animals species on earth, including 90 percent of all of the plankton in the ocean, but also led to the die-out of the dinosaurs.
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| ©SpaceDaily.com |
| The Caloris Basin is the youngest-known large impact basin on Mercury. |
As NASA's MESSENGER spacecraft prepares for its second flyby of Mercury, new analyses of data from the first flyby will be presented at the European Planetary Science Congress in Munster on Tuesday 23rd September
Dr Sean Solomon, MESSENGER's Principal Investigator, will present a model that suggests that the origin of the Pantheon Fossae, a radiating web of troughs located in the giant Caloris Basin, is directly linked to an impact crater at the centre of the web.
San Francisco, CA -- Professor Karlene Roberts has never donned a spacesuit nor orbited around the planet, but the spirited organizational behavior expert at UC Berkeley's Haas School of Business was tapped to help a committee of astronauts, diplomats, and legal experts find ways to mitigate the impact of an asteroid hitting Earth.
NASA's Hubble Space Telescope has captured a rare alignment between two spiral galaxies. The outer rim of a small, foreground galaxy is silhouetted in front of a larger background galaxy. Skeletal tentacles of dust can be seen extending beyond the small galaxy's disk of starlight.
Such outer dark dusty structures, which appear to be devoid of stars, like barren branches, are rarely so visible in a galaxy because there is usually nothing behind them to illuminate them. Astronomers have never seen dust this far beyond the visible edge of a galaxy. They do not know if these dusty structures are common features in galaxies.
Understanding a galaxy's color and how dust affects and dims that color are crucial to measuring a galaxy's true brightness. By knowing the true brightness, astronomers can calculate the galaxy's distance from Earth.
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| ©NASA, ESA, and The Hubble Heritage Team (STScI/AURA). Acknowledgement: B. Holwerda (Space Telescope Science Institute) and J. Dalcanton (University of Washington) |
| Astronomers used Hubble's Advanced Camera for Surveys to snap images of NGC 253 when they spied the two galaxies in the background. From ground-based telescopes, the two galaxies look like a single blob. But the Advanced Camera's sharp "eye" distinguished the blob as two galaxies, cataloged as 2MASX J00482185-2507365. |
Such outer dark dusty structures, which appear to be devoid of stars, like barren branches, are rarely so visible in a galaxy because there is usually nothing behind them to illuminate them. Astronomers have never seen dust this far beyond the visible edge of a galaxy. They do not know if these dusty structures are common features in galaxies.
Understanding a galaxy's color and how dust affects and dims that color are crucial to measuring a galaxy's true brightness. By knowing the true brightness, astronomers can calculate the galaxy's distance from Earth.
The supernova, called SN 1996cr, was first singled out in 2001 by Franz Bauer. Bauer noticed a bright, variable source in the Circinus spiral galaxy, using NASA's Chandra X-ray Observatory. Although the source displayed some exceptional properties Bauer and his Penn State colleagues could not identify its nature confidently at the time.
It was not until years later that Bauer and his team were able to confirm that this object was a supernova. Clues from a spectrum obtained by ESO's Very Large Telescope led the team to start the real detective work of searching through data from 18 different telescopes, both ground- and space-based, nearly all of which existed. Because this object was found in an interesting nearby galaxy, the public archives of these telescopes contained abundant observations.
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| ©X-ray (NASA/CXC/Columbia/F.Bauer et al); Visible light (NASA/STScI/UMD/A.Wilson et al.) |
| This composite image shows the central regions of the nearby Circinus galaxy, located about 12 million light years away. Data from NASA's Chandra X-ray Observatory is shown in blue and data from the NASA/ESA Hubble Space telescope is shown in yellow ("I-band"), red (hydrogen emission), cyan ("V-band") and light blue (oxygen emission). The blue source near the lower right hand corner of the image is the supernova SN 1996cr, that has finally been identified over a decade after it exploded. The supernova was first singled out in 2001 as a bright, variable object in a Chandra image, but it was not confirmed as a supernova until years later, when clues from a spectrum obtained with ESO's Very Large Telescope led the team to start the real detective work of searching through data from 18 different telescopes, both ground- and space-based, nearly all of which was in the archives. SN 1996cr is one of the nearest supernovae in the last 25 years. |
It was not until years later that Bauer and his team were able to confirm that this object was a supernova. Clues from a spectrum obtained by ESO's Very Large Telescope led the team to start the real detective work of searching through data from 18 different telescopes, both ground- and space-based, nearly all of which existed. Because this object was found in an interesting nearby galaxy, the public archives of these telescopes contained abundant observations.
An artificial meteorite designed by the European Space Agency has shown that traces of life in a martian meteorite could survive the violent heat and shock of entry into the Earth's atmosphere. The experiment's results also suggest that meteorite hunters should widen their search to include white rocks if we are to find traces of life in martian meteorites.
The STONE-6 experiment tested whether sedimentary rock samples could withstand the extreme conditions during a descent though the Earth's atmosphere where temperatures reached at least 1700 degrees Celsius. After landing, the samples were transported in protective holders to a laboratory clean-room at ESTEC and examined to see if any traces of life remained. The results will be presented by Dr Frances Westall at the European Planetary Science Congress on 25th September.
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| ©Europlanet |
| The Foton-M3 capsule immediately after landing. The STONE-6 rock samples were fixed in the circular positions at the left side of the capsule. |
The STONE-6 experiment tested whether sedimentary rock samples could withstand the extreme conditions during a descent though the Earth's atmosphere where temperatures reached at least 1700 degrees Celsius. After landing, the samples were transported in protective holders to a laboratory clean-room at ESTEC and examined to see if any traces of life remained. The results will be presented by Dr Frances Westall at the European Planetary Science Congress on 25th September.
Astronomers have discovered a most bizarre celestial object that emitted 40 visible-light flashes before disappearing again. It is most likely to be a missing link in the family of neutron stars, the first case of an object with an amazingly powerful magnetic field that showed some brief, strong visible-light activity.
This weird object initially misled its discoverers as it showed up as a gamma-ray burst, suggesting the death of a star in the distant Universe. But soon afterwards, it exhibited some unique behaviour that indicates its origin is much closer to us. After the initial gamma-ray pulse, there was a three-day period of activity during which 40 visible-light flares were observed, followed by a brief near-infrared flaring episode 11 days later, which was recorded by ESO's Very Large Telescope. Then the source became dormant again.
"We are dealing with an object that has been hibernating for decades before entering a brief period of activity", explains Alberto J. Castro-Tirado, lead author of a new paper in the journal Nature.
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| ©ESO/L.Calçada |
| Astronomers have discovered a possible magnetar that emitted 40 visible-light flashes before disappearing again. Magnetars are young neutron stars with an ultra-strong magnetic field a billion billion times stronger than that of the Earth. The twisting of magnetic field lines in magnetars give rise to 'starquakes', which will eventually lead to an intense soft gamma-ray burst. In the case of the SWIFT source, the optical flares that reached the Earth were probably due to ions ripped out from the surface of the magnetar and gyrating around the field lines. |
This weird object initially misled its discoverers as it showed up as a gamma-ray burst, suggesting the death of a star in the distant Universe. But soon afterwards, it exhibited some unique behaviour that indicates its origin is much closer to us. After the initial gamma-ray pulse, there was a three-day period of activity during which 40 visible-light flares were observed, followed by a brief near-infrared flaring episode 11 days later, which was recorded by ESO's Very Large Telescope. Then the source became dormant again.
"We are dealing with an object that has been hibernating for decades before entering a brief period of activity", explains Alberto J. Castro-Tirado, lead author of a new paper in the journal Nature.
The deep interior of Neptune, Uranus and Earth may contain some solid ice.
Through first-principle molecular dynamics simulations, Lawrence Livermore National Laboratory scientists, together with University of California, Davis collaborators, used a two-phase approach to determine the melting temperature of ice VII (a high-pressure phase of ice) in pressures ranging from 100,000 to 500,000 atmospheres.
For pressures between 100,000 and 400,000 atmospheres, the team, led by Eric Schwegler, found that ice melts as a molecular solid (similar to how ice melts in a cold drink). But in pressures above 450,000 atmospheres, there is a sharp increase in the slope of the melting curve due to molecular disassociation and proton diffusion in the solid, prior to melting, which is typically referred to as a superionic solid phase.
"The sharp increase in the melting curves slope opens up the possibility that water exists as a solid in the deep interior of planets such as Neptune, Uranus and Earth," Schwegler said.
Through first-principle molecular dynamics simulations, Lawrence Livermore National Laboratory scientists, together with University of California, Davis collaborators, used a two-phase approach to determine the melting temperature of ice VII (a high-pressure phase of ice) in pressures ranging from 100,000 to 500,000 atmospheres.
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| ©Visualization by Eric Schwegler/LLNL |
| A snapshot from a first-principle molecular dynamics simulation of ice-VII (on the right) in contact with liquid water (on the left). As the simulation progresses the position of the solid-liquid interface can be monitored and used to accurately determine the location of the melting temperature of water under high pressure conditions. |
For pressures between 100,000 and 400,000 atmospheres, the team, led by Eric Schwegler, found that ice melts as a molecular solid (similar to how ice melts in a cold drink). But in pressures above 450,000 atmospheres, there is a sharp increase in the slope of the melting curve due to molecular disassociation and proton diffusion in the solid, prior to melting, which is typically referred to as a superionic solid phase.
"The sharp increase in the melting curves slope opens up the possibility that water exists as a solid in the deep interior of planets such as Neptune, Uranus and Earth," Schwegler said.
NASA Goddard scientist Rick Lyon has been working on potential missions and technologies to find planets around other stars (called exoplanets or extrasolar planets) since the late 1980s. Only recently has he begun to believe that NASA may actually fly a planet-finding mission in his lifetime. "This is the closest it's come to being real," he said.
Lyon and other scientists and engineers at NASA's Goddard Space Flight Center in Greenbelt, Md., have joined teams studying optics technologies for three possible exoplanet missions: the Extrasolar Planetary Imaging Coronagraph (EPIC), the New Worlds Observer (NWO), and the eXtrasolar Planet Characterization (XPC) mission.
The possibility of a mission devoted to planet finding is tantalizing, especially to those interested in ratcheting up a science that began 13 years ago when astronomers found and confirmed the existence of the first planet outside the solar system. Since then, scientists have confirmed nearly 300, most of which are gas giants like Jupiter. However, most of these detections have been indirect, because the planets are too faint to be seen directly. Instead, their presence is revealed by measuring how much the unseen world's gravity pulls on its parent star.
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| ©NASA and Northrop Grumman |
| Artist's concept of the New Worlds Observatory. The dark, flower-shaped object in the center is the star shade. |
Lyon and other scientists and engineers at NASA's Goddard Space Flight Center in Greenbelt, Md., have joined teams studying optics technologies for three possible exoplanet missions: the Extrasolar Planetary Imaging Coronagraph (EPIC), the New Worlds Observer (NWO), and the eXtrasolar Planet Characterization (XPC) mission.
The possibility of a mission devoted to planet finding is tantalizing, especially to those interested in ratcheting up a science that began 13 years ago when astronomers found and confirmed the existence of the first planet outside the solar system. Since then, scientists have confirmed nearly 300, most of which are gas giants like Jupiter. However, most of these detections have been indirect, because the planets are too faint to be seen directly. Instead, their presence is revealed by measuring how much the unseen world's gravity pulls on its parent star.
