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| ©NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
| The Spider: MESSENGER obtained high-resolution images of the floor of the Caloris basin on January 14, 2008. Near the center of the basin, this remarkable feature -- nicknamed "the spider" by the science team -- was revealed. A set of troughs radiating outward are interpreted to be the result of the breaking apart of the floor materials that filled the Caloris basin after its formation. Other troughs near the center form a polygonal pattern. An impact crater about 40 km (~25 miles) in diameter appears to be centered on "the spider." |
Science & Technology
The recent flyby of Mercury by NASA's MESSENGER spacecraft has given scientists an entirely new look at a planet once thought to have characteristics similar to those of Earth's moon. Researchers are amazed by the wealth of images and data that show a unique world with a diversity of geological processes and a very different magnetosphere from the one discovered and sampled more than 30 years ago.
A space rock that smashed into Canada more than 200 million years ago is being blamed for health risks faced today by several communities in central Manitoba, according to a new international study of groundwater quality around the ancient Lake St. Martin meteorite crater north of Winnipeg.
In what's being described as the first-ever finding of a modern-day health threat posed by a prehistoric meteorite strike, the researchers say elevated levels of fluoride and other chemicals in the area's groundwater can be traced to the shattering of subsurface granite when the extraterrestrial object slammed into Earth nearly a quarter of a billion years ago.
In what's being described as the first-ever finding of a modern-day health threat posed by a prehistoric meteorite strike, the researchers say elevated levels of fluoride and other chemicals in the area's groundwater can be traced to the shattering of subsurface granite when the extraterrestrial object slammed into Earth nearly a quarter of a billion years ago.
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| ©Google Maps |
| An aerial view of Lake St. Martin, Manitoba. |
A team of Korean scientists in Antarctica has discovered a large meteorite weighing 3.7 kg.
The Korea Polar Research Institute under the Korea Ocean Research and Development Institute said Monday that the country's second exploration team to Antarctica discovered 13 meteorites in the western Thiel Mountains on Dec. 24, 29 and 30.
The Korea Polar Research Institute under the Korea Ocean Research and Development Institute said Monday that the country's second exploration team to Antarctica discovered 13 meteorites in the western Thiel Mountains on Dec. 24, 29 and 30.
"I throw more power into my voice, and now the flame is extinguished," wrote Irish scientist John Tyndall about his experiments with sound and fire in 1857. Countless public demonstrations and a handful of lab tests later, researchers are still struggling to determine exactly how sound snuffs flames.
Sound travels in waves, which are simply variations of pressure in a medium - whether solid, liquid or gas. The energy from vibrating objects, such as speaker membranes, moves from particle to particle in the air in a repeating pattern of high- and low-pressure zones that we perceive as sound. According to the ideal gas law, temperature, pressure and volume are related; therefore, a decrease in pressure can lead to a corresponding decrease in temperature, which may explain how sound can extinguish a flame.
Sound travels in waves, which are simply variations of pressure in a medium - whether solid, liquid or gas. The energy from vibrating objects, such as speaker membranes, moves from particle to particle in the air in a repeating pattern of high- and low-pressure zones that we perceive as sound. According to the ideal gas law, temperature, pressure and volume are related; therefore, a decrease in pressure can lead to a corresponding decrease in temperature, which may explain how sound can extinguish a flame.
The sudden emergence of American English is an example of how languages evolve rapidly when people want to carve out a new identity, and mirror the way that new species evolve, according to a new study.
Some have proposed that languages change in a way seen in the evolution of living things, which tends to come in bursts of rapid change. Now a British-led international team has done a survey of major languages to see if this really is the case, reporting its findings in the journal Science.
Some have proposed that languages change in a way seen in the evolution of living things, which tends to come in bursts of rapid change. Now a British-led international team has done a survey of major languages to see if this really is the case, reporting its findings in the journal Science.
A team of geologists believes it has found the incoming space rock's impact crater, and dating suggests its formation coincided with the celestial vision said to have converted a future Roman emperor to Christianity.
It was just before a decisive battle for control of Rome and the empire that Constantine saw a blazing light cross the sky and attributed his subsequent victory to divine help from a Christian God.
Constantine went on to consolidate his grip on power and ordered that persecution of Christians cease and their religion receive official status.
Civil war
In the fourth century AD, the fragmented Roman Empire was being further torn apart by civil war. Constantine and Maxentius were bitterly fighting to be the sole emperor.
Constantine was the son of the western emperor Constantius Chlorus. When he died in 306, his father's troops proclaimed Constantine emperor.
" ...a most marvellous sign appeared to him from heaven... " Eusebius
It was just before a decisive battle for control of Rome and the empire that Constantine saw a blazing light cross the sky and attributed his subsequent victory to divine help from a Christian God.
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| ©Unknown |
Constantine went on to consolidate his grip on power and ordered that persecution of Christians cease and their religion receive official status.
Civil war
In the fourth century AD, the fragmented Roman Empire was being further torn apart by civil war. Constantine and Maxentius were bitterly fighting to be the sole emperor.
Constantine was the son of the western emperor Constantius Chlorus. When he died in 306, his father's troops proclaimed Constantine emperor.
" ...a most marvellous sign appeared to him from heaven... " Eusebius
Sporting a trunk-like nose and a jet-black rump, a new species of a bizarre furry mammal was caught on film as it scuttled along a forest floor in Tanzania.
Researchers first sighted the elephant-shrew (Rhynchocyon udzungwensis) in 2005, but not until recently did they confirm the animal as a new species of giant sengi. They filmed the cat-size creature in March 2006 as it twitched its slender snout while searching for insect snacks in the Ndundulu Forest in Tanzania.
Researchers first sighted the elephant-shrew (Rhynchocyon udzungwensis) in 2005, but not until recently did they confirm the animal as a new species of giant sengi. They filmed the cat-size creature in March 2006 as it twitched its slender snout while searching for insect snacks in the Ndundulu Forest in Tanzania.
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| ©Francesco Rover / Trento Museum of Natural Sciences |
| The new elephant-shrew species is confined to two high-altitude forests in the mountains of Tanzania. |
An ancient iron ore mine discovered in Peru reveals civilizations in the Andes mined the valuable rock before the Inca Empire.
Archaeologists have known that people in the Old and New Worlds have dug for ore for millennia, but there is little evidence for such mines in the ancient Americas.
"What we found is the only hematite mine - a type of iron also known as ochre - recorded in South America prior to the Spanish conquest," said researcher Kevin Vaughn, an archaeologist at Purdue University in West Lafayette, Ind. "This discovery demonstrates that iron ores were important to ancient Andean civilizations."
Archaeologists have known that people in the Old and New Worlds have dug for ore for millennia, but there is little evidence for such mines in the ancient Americas.
"What we found is the only hematite mine - a type of iron also known as ochre - recorded in South America prior to the Spanish conquest," said researcher Kevin Vaughn, an archaeologist at Purdue University in West Lafayette, Ind. "This discovery demonstrates that iron ores were important to ancient Andean civilizations."
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| ©Purdue News Service photo/David Umberger |
| Kevin J. Vaughn, a Purdue assistant professor of anthropology, holds a pottery fragment he discovered at an excavation site in Nasca, Peru. The piece of pottery is from about the 5th century A.D., the same time period as other artifacts he uncovered at an ancient mine. Vaughn conjectures the mine was the source of some of the iron ore pigments used to produce the vibrant colors as seen on this pottery. |
We might think we control the climate but unless we harness the powers of our microbial co-habitants on this planet we might be fighting a losing battle, according to an article in the February 2008 issue of Microbiology Today. Humans are continually altering the atmosphere.
"Arrogant organisms that we are, it is easy to view this as something entirely novel in Earth's history," says Dr Dave Reay from the University of Edinburgh. "In truth of course, micro-organisms have been at it for billions of years."
"Arrogant organisms that we are, it is easy to view this as something entirely novel in Earth's history," says Dr Dave Reay from the University of Edinburgh. "In truth of course, micro-organisms have been at it for billions of years."
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| ©Unknown |
| 90 billion tonnes of carbon a year is absorbed from the atmosphere by the oceans, and almost as much is released; microbes play a key role in both. |
Astronomers at the University of St Andrews believe they can "simplify the dark side of the universe" by shedding new light on two of its mysterious constituents.
Dr HongSheng Zhao, of the University's School of Physics and Astronomy, has shown that the puzzling dark matter and its counterpart dark energy may be more closely linked than was previously thought.
Only 4% of the universe is made of known material - the other 96% is traditionally labelled into two sectors, dark matter and dark energy.
A British astrophysicist and Advanced Fellow of the UK's Science and Technology Facilities Council, Dr Zhao points out, "Both dark matter and dark energy could be two faces of the same coin.
"As astronomers gain understanding of the subtle effects of dark energy in galaxies in the future, we will solve the mystery of astronomical dark matter at the same time. "
Dr HongSheng Zhao, of the University's School of Physics and Astronomy, has shown that the puzzling dark matter and its counterpart dark energy may be more closely linked than was previously thought.
Only 4% of the universe is made of known material - the other 96% is traditionally labelled into two sectors, dark matter and dark energy.
A British astrophysicist and Advanced Fellow of the UK's Science and Technology Facilities Council, Dr Zhao points out, "Both dark matter and dark energy could be two faces of the same coin.
"As astronomers gain understanding of the subtle effects of dark energy in galaxies in the future, we will solve the mystery of astronomical dark matter at the same time. "
