Scientists take early Mars' temperature
PASADENA, Calif., Oct. 12 (UPI) -- U.S. researchers say they've determined the surface temperature of early Mars for the first time, evidence consistent with a warmer and wetter Martian past.
Analyzing a 4-billion-year-old meteorite that originated near the surface of Mars then was blasted into space to land on Earth, scientist at the California Institute of Technology determined that the minerals in the meteorite formed at about 64 degrees Fahrenheit, or 18 degrees Celsius.
"The thing that's really cool is that 18 degrees is not particularly cold nor particularly hot," Woody Fischer, assistant professor of geobiology, said in a CalTech release Wednesday.
Scientists have been debating the planet's past climate and whether it once had liquid water.
"There are all these ideas that have been developed about a warmer, wetter early Mars," Fischer said.
The Mars rovers and orbiting spacecraft have found ancient deltas, rivers, lakebeds, and mineral deposits, suggesting water in fact once flowed on Mars.
The new finding supports that, researchers said.
"It's proof that early in the history of Mars, at least one place on the planet was capable of keeping an Earthlike climate for at least a few hours to a few days," CalTech geochemist John Eiler said.
Genome of the Black Death sequenced
HAMILTON, Ontario, Oct. 12 (UPI) -- Canadian researchers say they've sequenced the genome of the Black Death, one of the most devastating epidemics in human history.
This is the first reconstruction of the genome of any ancient pathogen, and it could lead to a better understanding of modern infectious diseases, researchers at McMaster University in Ontario said.
The sequenced genome will allow researchers to track changes in the pathogen's evolution and virulence over time, a university release said Wednesday.
"The genomic data show that this bacterial strain, or variant, is the ancestor of all modern plagues we have today worldwide," geneticist Hendrik Poinar said. "Every outbreak across the globe today stems from a descendant of the medieval plague."
The Black Death was a variant of the Yersinia pestis bacterium that killed 50 million Europeans between 1347 and 1351.
"We found that in 660 years of evolution as a human pathogen, there have been relatively few changes in the genome of the ancient organism, but those changes, however small, may or may not account for the noted increased virulence of the bug that ravaged Europe," Poinar said.
World demand for metals said a concern
LONDON, Oct. 12 (UPI) -- An insatiable demand for consumer electronic products could threaten worldwide shortages and bottlenecks of some metals, British scientists warn.
Leading geologists, writing in the journal Nature Geoscience, say there's danger in the ongoing surge in demand for metals.
"Mobile phones contain copper, nickel, silver and zinc, aluminium, gold, lead, manganese, palladium, platinum and tin," Gawen Jenkin of the University of Leicester said. "More than a billion people will buy a mobile in a year -- so that's quite a lot of metal.
"And then there's the neodymium in your laptop, the iron in your car, the aluminium in that soft drinks can -- the list goes on."
Scientists gathered at a meeting of the Geological Society of London to discuss the issue.
"With ever-greater use of these metals, are we running out? That was one of the questions we addressed at our meeting," Jenkin said.
"It is reassuring that there's no immediate danger of 'peak metal' as there's quite a lot in the ground still -- but there will be shortages and bottlenecks of some metals like indium due to increased demand."
The concept of "peak metal" is similar to the notion to "peak oil," referring to the maximum sustainable rate of production of a finite resource.
WASHINGTON, Oct. 12 (UPI) -- Hot deserts usually come to mind as prime places for solar power, but some of Earth's coldest places could be good energy sources, Japanese researchers say.
Kotaro Kawajiri and his colleagues, in an article in the U.S. journal Environmental Science & Technology, say many cold regions at high elevations -- including the Himalaya Mountains, the Andes and even Antarctica --receive so much sunlight their potential for producing power from the sun is higher than some desert areas.
Part of their study took into account the effects of temperature on the output of solar cells, and future work will take into consideration variables such as transmission losses and snowfall, they said.
Still, they said, the potential of high, cold locations is attractive.
The Himalayas, for example, which include Mount Everest, could be an ideal locale for solar fields providing electricity for the fast-expanding economy of the People's Republic of China, the researchers said.