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PhDs have been searching for a solution to the plastic waste problem, and this 16-year-old finds the answer.
It's not your average science fair when the 16-year-old winner manages to solve a global waste crisis. But such was the case at last month's Canadian Science Fair in Waterloo, Ontario, where Daniel Burd, a high school student at Waterloo Collegiate Institute, presented his research on microorganisms that can rapidly biodegrade plastic.
© X-ray (NASA/CXC/Penn State/S.Park and J.Lee); IR (NASA/JPL-Caltech)SNR 0104 is the remains of a supernova in the Small Magellanic Cloud, a nearby galaxy located about 190,000 light years away. The asymmetrical shape is unusual for such a supernova and might be caused by jets in the explosion or clumps of nearby gas.
In this composite made of X-rays from Chandra shown in purple and infrared data from Spitzer shown in green and red, SNR 0104 looks unlike other likely Type Ia remnants found in our own Galaxy. While objects such as the Kepler and Tycho supernova remnants appear circular, the shape of SNR 0104 in X-rays is not.
Instead, the image is dominated by two bright lobes of emission (seen to the upper right and lower left). The large amount of iron in these lobes indicates that SNR 0104 was likely formed by a Type Ia supernova.
© UnknownSanderson's calculations showed an unexpected diversity in the ultracool subdwarf orbits. Some plunge deep into the center of the Milky Way on eccentric, comet-like tracks; others make slow, swooping loops far beyond the Sun's orbit. Unlike the majority of nearby stars, most of the ultracool subdwarfs spend a great deal of time thousands of light-years above or below the disk of the Milky Way.
Adam Burgasser and John Bochanski of MIT presented the findings at the American Astronomical Society's semi-annual meeting in Pasadena, Calif. The result clarifies the origins of these peculiar, faint stars, and may provide new details on the types of stars the Milky Way has acquired from other galaxies.
Ultracool subdwarfs were first recognized as a unique class of stars in 2003, and are distinguished by their low temperatures ("ultracool") and low concentrations of elements other than hydrogen and helium ("subdwarf").
© NASALooming vertical structures, seen here for the first time and created by Saturn's moon Daphnis, rise above the planet's otherwise flat, thin disk of rings to cast long shadows in this Cassini image.
The new findings are presented in a paper authored by Cassini imaging scientists and published online in the Astronomical Journal.
The search for ring material extending well above and below Saturn's ring plane has been a major goal of the imaging team during Cassini's "Equinox Mission," the two-year period containing exact equinox - that moment when the sun is seen directly overhead at noon at the planet's equator.
© Unknown
Located near the Aquila rift in the Galactic plane at a distance of 23,000 light-years, this cloud condensation has a mass 120 times that of the Sun contained within a volume smaller than the Oort cloud of comets orbiting at the edge of our solar system, and its temperature is less than 18 degrees above absolute zero. Such a large amount of cold dense gas is likely to evolve into one or more massive stars.
Stem cells responsible for hair color lose self-renewing abilities
Gray hair may be a mark of distinction in some circles, but it's also a sign of a depleted stem cell population. DNA damage causes stem cells that produce hair-color cells in mice to lose their "stemness," leaving brown hair gray, a report in the June 12 Cell shows. The results suggest a new way stem cell populations can be depleted as cells accumulate DNA damage over time.
The new study "opens up a new paradigm for how we're going to study stem cell aging in many systems," comments Kevin Mills of the Jackson Laboratory in Bar Harbor, Maine. The report "fills in what's been a hole in our understanding of stem cell biology."
Colorful locks depend on a group of special cells in hair follicles called melanocyte stem cells. Each of these cells divides into two cells: One that replaces itself and another that differentiates into a pigment-producing daughter cell called a melanocyte, which imbues hair with its browns, reds and blacks. Earlier research has suggested that the depletion of these stem cells was to blame for grayness. But how exactly these stem cells disappeared was mysterious. With no more stem cells around to produce melanocytes, hair turns gray.
Gray hair may be a mark of distinction in some circles, but it's also a sign of a depleted stem cell population. DNA damage causes stem cells that produce hair-color cells in mice to lose their "stemness," leaving brown hair gray, a report in the June 12 Cell shows. The results suggest a new way stem cell populations can be depleted as cells accumulate DNA damage over time.
The new study "opens up a new paradigm for how we're going to study stem cell aging in many systems," comments Kevin Mills of the Jackson Laboratory in Bar Harbor, Maine. The report "fills in what's been a hole in our understanding of stem cell biology."
Colorful locks depend on a group of special cells in hair follicles called melanocyte stem cells. Each of these cells divides into two cells: One that replaces itself and another that differentiates into a pigment-producing daughter cell called a melanocyte, which imbues hair with its browns, reds and blacks. Earlier research has suggested that the depletion of these stem cells was to blame for grayness. But how exactly these stem cells disappeared was mysterious. With no more stem cells around to produce melanocytes, hair turns gray.
An ancient burial pit containing 45 severed skulls, that could be a mass war grave dating back to Roman times, has been found under a road being built for the 2012 British Olympics.
Archaeologists, who have only just begun excavating the site, say they do not yet know who the bones might belong to.
"We think that these dismembered bodies are likely to be native Iron Age Britons. The question is -- how did they die and who killed them," said dig head, David Score, of Oxford Archaeology.
"Were they fighting amongst themselves? Were they executed by the Romans? Did they die in a battle with the Romans?
"The exciting scenario for us possibly is that there were skirmishes with the invading Romans and that's how they ended up chopped up in a pit," he told Reuters.
Archaeologists, who have only just begun excavating the site, say they do not yet know who the bones might belong to.
"We think that these dismembered bodies are likely to be native Iron Age Britons. The question is -- how did they die and who killed them," said dig head, David Score, of Oxford Archaeology.
"Were they fighting amongst themselves? Were they executed by the Romans? Did they die in a battle with the Romans?
"The exciting scenario for us possibly is that there were skirmishes with the invading Romans and that's how they ended up chopped up in a pit," he told Reuters.
© REUTERS/NIST/HandoutThe periodic table in an undated image. A new, superheavy chemical element numbered 112 will soon be officially included in the periodic table, German researchers said.
A team in the southwest German city of Darmstadt first produced 112 in 1996 by firing charged zinc atoms through a 120-meter-long particle accelerator to hit a lead target.
"The new element is approximately 277 times heavier than hydrogen, making it the heaviest element in the periodic table," the scientists at the GSI Helmholtz Center for Heavy Ion Research said in a statement late on Wednesday.
© Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSFAn extrasolar planet may have been detected in nearby Andromeda
The idea is to use gravitational microlensing, in which a distant source star is briefly magnified by the gravity of an object passing in front of it. This technique has already found several planets in our galaxy, out to distances of thousands of light years.
Extending the method from thousands to millions of light years won't be easy, says Philippe Jetzer of the University of Zürich in Switzerland, but it should be possible.
Jetzer and five colleagues simulated microlensing from the Andomeda galaxy, which is more than 2 million light years away. They started by populating Andromeda with planets, assuming that they will have the same range of sizes and orbits as known exoplanets in our own galaxy. "These are reasonable guesses, probably right within a factor of two," Jetzer told New Scientist.
Meteorite fragments of the first asteroid ever spotted in space before it slammed into Earth's atmosphere last year were recovered by scientists from the deserts of Sudan.
These precious pieces of space rock, described in a study detailed in the March 26 issue of the journal Nature, could be an important key to classifying meteorites and asteroids and determining exactly how they formed.
The asteroid was detected by the automated Catalina Sky Survey telescope at Mount Lemmon , Ariz., on Oct. 6, 2008. Just 19 hours after it was spotted, it collided with Earth's atmosphere and exploded 23 miles (37 kilometers) above the Nubian Desert of northern Sudan.
Because it exploded so high over Earth's surface, no chunks of it were expected to have made it to the ground. Witnesses in Sudan described seeing a fireball, which ended abruptly.
But Peter Jenniskens, a meteor astronomer with the SETI Institute's Carl Sagan Center, thought it would be possible to find some fragments of the bolide. Along with Muawia Shaddad of the University of Khartoum and students and staff, Jenniskens followed the asteroid's approach trajectory and found 47 meteorites strewn across an 18-mile (29-km) stretch of the Nubian Desert.
These precious pieces of space rock, described in a study detailed in the March 26 issue of the journal Nature, could be an important key to classifying meteorites and asteroids and determining exactly how they formed.
The asteroid was detected by the automated Catalina Sky Survey telescope at Mount Lemmon , Ariz., on Oct. 6, 2008. Just 19 hours after it was spotted, it collided with Earth's atmosphere and exploded 23 miles (37 kilometers) above the Nubian Desert of northern Sudan.
Because it exploded so high over Earth's surface, no chunks of it were expected to have made it to the ground. Witnesses in Sudan described seeing a fireball, which ended abruptly.
But Peter Jenniskens, a meteor astronomer with the SETI Institute's Carl Sagan Center, thought it would be possible to find some fragments of the bolide. Along with Muawia Shaddad of the University of Khartoum and students and staff, Jenniskens followed the asteroid's approach trajectory and found 47 meteorites strewn across an 18-mile (29-km) stretch of the Nubian Desert.
