Science & TechnologyS


Info

Flashback Goldmine bug DNA may be key to alien life

Catherine Brahic
New Scientist
Thu, 09 Oct 2008 21:10 UTC
D. audaxviator
© Greg Wanger / Gordon SouthamD. audaxviator lives alone, without light or oxygen 2.8 kilometres down inside a South African goldmine.

A bug discovered deep in a goldmine and nicknamed "the bold traveller" has got astrobiologists buzzing with excitement. Its unique ability to live in complete isolation of any other living species suggests it could be the key to life on other planets.

A community of the bacteria Candidatus Desulforudis audaxviator has been discovered 2.8 kilometres beneath the surface of the Earth in fluid-filled cracks of the Mponeng goldmine in South Africa. Its 60 °C home is completely isolated from the rest of the world, and devoid of light and oxygen.

Dylan Chivian of the Lawrence Berkeley National Laboratory, California, studied the genes found in samples of the fluid to identify the organisms living within it, expecting to find a mix of species. Instead, he found that 99.9% of the DNA belonged to one bacterium, a new species. The remaining DNA was contamination from the mine and the laboratory.
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Meteor

Close call: weird asteroid skims Earth today

Patricia Phillips
San Francisco Examiner
Sun, 25 Jan 2009 19:51 UTC
Coorbital asteroid image
© NASA
There's a newly-discovered weird asteroid kid on Earth's block, and it's moved in close. Really, really close, in space terms.

Asteroid 2009 BD is cruising by us today at a distance of only about 400,000 miles, according to NASA's Near Earth Object Program. This strange asteroid is estimated to be 5. 7 meters to 13 meters in diameter.
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Info

Dinosaurs could survive cold conditions

Richard Gray
UK Telegraph
Sun, 25 Jan 2009 18:42 UTC
Dinosaur skeleton
© Lonely PlanetDinosaurs could have lived and reproduced in much colder climates than we orginally thought.
Dinosaurs were able to survive colder temperatures than was previously thought, according to new research that casts doubt on theories that they were killed off by plummeting temperatures caused by climate change.

Palaeontologists have unearthed a rich variety of dinosaur fossils in an area that would have been one of the most northerly regions of the world in the period just before the giant reptiles died out, between 65 and 68 million years ago.

At the time, the world was far warmer and the continents were still to move to their current positions. Northeastern Russia, where the remains have been found, would have been just 1,000 miles from the North Pole, inside what is now called the Arctic Circle. Average temperatures would have been around 50F (10C).

Comment: There is ample evidence that when we are bombarded by meteorite/s, there has been noted "fogs", "ill smelling fumes" and such. It could just be possible that not only was the sun blotted out for many months - years even - but there were also foreign bacteria and viruses being strewed about making the dinosaurs sick enough to die.

And maybe the predators were also ingesting the diseases from those they ate who were infected.

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Meteor

Curious Asteroid Flyby


SpaceWeather.com
Sun, 25 Jan 2009 18:52 UTC
Newly-discovered asteroid 2009 BD is slowly passing by Earth today only 400,000 miles away. The small 10m-wide space rock poses no threat, but it merits attention anyway. The orbit of 2009 BD appears to be almost identical to the orbit of Earth. 2009 BD may be a rare co-orbital asteroid, circling the sun in near-tandem with our planet. Extrapolating the motion of 2009 BD into the future, we see that it remains in the vicinity of Earth for many months to come, never receding farther than 0.1 AU (9.3 million miles) until Nov. 2010. Future observations may reveal the nature of this strange asteroid; stay tuned! [3D orbit] [ephemeris]
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Magnify

Genetic Tricks of Parasites

Stéphan Reebs
Live Science
Sun, 25 Jan 2009 15:44 UTC
Parasites typically don't have as many genes as their free-living relatives do. Life is simple because their hosts do the hard work of moving about, getting food, and avoiding predators.

Consider the nematodes (aka roundworms). The common free-living soil dweller Caenorhabditis elegans - which in 1998 became the first multicellular animal ever to have its genome decoded - has about 20,000 genes, whereas Brugia malayi, the parasite that causes the tropical disease filariasis, has just 11,500. Yet in the course of parasite evolution, genomes may need to grow before they can shrink.
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Pistol

UCSF Study Raises Doubts About Stun Gun Safety

Elizabeth Fernandez
San Francisco Chronicle
Sat, 24 Jan 2009 11:01 UTC
Taser
© Herb Swanson/AP
The number of in-custody sudden deaths rose dramatically during the first year California law enforcement agencies began using stun guns, raising questions about the safety of the devices, according to a new study at UCSF.

The electronic weapons are intended to be a nonlethal alternative to the gun.

"Tasers are not as safe as thought," said Dr. Byron Lee, one of the cardiologists involved in studying the death rate related to Tasers, the most widely used stun gun. "And if they are used, they should be used with caution."

The researchers analyzed sudden death data from 50 law enforcement agencies in the state that use Tasers. They compared the death rate pre- and post-Taser deployment - analyzing data for five years before each agency began using Tasers and five years afterward.
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Telescope

Supermassive Black Holes Not Guilty Of Shutting Down Star Formation


Science Daily
Sun, 25 Jan 2009 03:05 UTC
galaxies stop forming stars
© SloSchawinski and his team compared the light from 177 galaxies, such as the one on the left, to the light emitted by the AGN at their centers (right) to show that the galaxies stop forming stars long before their AGN reach their peak brightness.

A team of Yale University astronomers has discovered that galaxies stop forming stars long before their central supermassive black holes reach their most powerful stage, meaning the black holes can't be responsible for shutting down star formation.

Until recently, astronomers believed that active galactic nuclei (AGN) - the supermassive, extremely energetic black holes at the centers of many young galaxies - were responsible for shutting down star formation in their host galaxies once they grew large enough. It was thought that AGN feed on the surrounding galactic material, producing enormous amounts of energy (expelled in the form of light) and heat the surrounding material so that it can no longer cool and condense into stars.
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Evil Rays

Cosmic Rays Detected Deep Underground Reveal Secrets Of Upper Atmosphere


Science Daily
Sun, 25 Jan 2009 01:31 UTC
Image
© Peter GinterFermilab scientist Nike Saoulidou, a member of the MINOS collaboration, with one of the two "horns" that focus the particle beam for the MINOS neutrino experiment.

Cosmic-rays detected half a mile underground in a disused U.S. iron-mine can be used to detect major weather events occurring 20 miles up in the Earth's upper atmosphere, a new study has revealed.

Published in the journal Geophysical Research Letters and led by scientists from the UK's National Centre for Atmospheric Science (NCAS) and the Science and Technology Facilities Council (STFC), this remarkable study shows how the number of high-energy cosmic-rays reaching a detector deep underground, closely matches temperature measurements in the upper atmosphere (known as the stratosphere). For the first time, scientists have shown how this relationship can be used to identify weather events that occur very suddenly in the stratosphere during the Northern Hemisphere winter.

These events can have a significant effect on the severity of winters we experience, and also on the amount of ozone over the poles - being able to identify them and understand their frequency is crucial for informing our current climate and weather-forecasting models to improve predictions.
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Satellite

Spy Satellites Turn Their Gaze Onto Each Other


New Scientist
Sat, 24 Jan 2009 10:14 UTC
Spy satellites have a new role: as well as watching us they are now spying on each other.

The Pentagon admitted last week that it is using two covert inspection satellites developed for the Defense Advanced Research Projects Agency to assess damage to a failed geostationary satellite - something no one suspected the US could do. If such satellites can get that close to a target, they could probably attack it.

The Department of Defense says its Mitex micro-satellites, which were launched in 2006, have been jetting around the geostationary ring and have now jointly inspected DSP 23, which was designed to pinpoint clandestine missile launches and nuclear tests, but which stopped working a year after its November 2007 launch. The micro-satellites are trying to nail the problem.
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Sun

NASA Sees Far Side of the Sun


SPACE.com
Fri, 23 Jan 2009 22:20 UTC
Sun
© NASAThe STEREO (Ahead) spacecraft observed this visually stunning prominence eruption on Sept. 29, 2008 in the 304 wavelength of extreme UV light. It rose up and cascaded to the right over several hours, appearing something like a flag unfurling, as it broke apart and headed into space. The material observed is actually ionized Helium at about 60,000 degrees. Prominences are relatively cool clouds of gas suspended above the sun and controlled by magnetic forces.

NASA's twin STEREO spacecraft are offering the first glimpse of the far side of the sun, the space agency announced today.

The two spacecraft, launched Oct. 25, 2006, are beaming back over-the-horizon images "that have researchers and forecasters glued to their monitors," according to a statement.

"This is a perspective we've never had before," says STEREO mission scientist Lika Guhathakurta of NASA headquarters. "We're now monitoring more than 270 degrees of solar longitude - that's 3/4ths of the star."
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