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GLOBAL UPDATE: Europe’s probe to Venus
Venus Express, Europe’s first probe to Earth’s mysterious sister planet, blasted into space from the Baikonur cosmodrome in Kazakhstan last week, with scientists hoping the mission will help them better understand the development of the greenhouse effect on Earth.
The probe’s successful launch on a Soyuz rocket was greeted with intense relief by European and Russian space officials gathered in the freezing cold just after dawn. Last month a European probe Cryosat was lost when its Russian launcher failed. A second successive failure would have put a severe strain on the fledgling partnership between Russia and Europe.
But the Russian Soyuz performed perfectly and Venus Express began its five-month, 26m-mile journey to the planet many scientists call Earth’s evil twin. It will be the first probe to visit Venus since Magellan in the early 1990s.
Scientists think the Earth and Venus had a similar start 4.6bn years ago during the solar system’s birth. But while one planet went bad, the other nurtures millions of species. One is a searing cauldron beset by a runaway greenhouse effect, the other a watery paradise. Venus Express will help scientists to understand why.
Two hours after liftoff, European Space Agency officials announced that Venus Express, a box-shaped probe the size of a small car, had been successfully fired on its journey. Twenty minutes later the first signal from the probe was picked up.
Venus Express will reach its target in April and begin surveying the planet with its range of detectors. It will measure the chemical composition of the atmosphere, take high-resolution photographs, and assess its magnetic field. Although Venus is Earth’s nearest planetary neighbour, previous space probes have revealed it to be a hellish world. The surface temperature is 465C, the atmosphere is a crushing 90 times more dense than ours, and the planet is shrouded in sulphuric acid droplets.
Clay wombs
Primordial clay “wombs” that lie scattered around ocean floors played a crucial role in fostering early life on Earth, according to a team of scientists. The clay structures were found in deep waters, in and around ocean floor volcanic vents called black smokers, so named because they churn out hot black particles from the Earth’s crust.
By providing a haven for molecules brought up from the Earth’s interior, the wombs protected them from the harsh environment until they formed the most basic building blocks of life, the scientists say. Black smokers form along the edges of mid-ocean ridges.
The rich variety of chemicals they emit supports a unique ecosystem including bizarre bacteria and unique species of worms. Scientists believe that these hot, sulphur-rich waters may have been ideal for life to evolve.
Until now researchers have been puzzled as to how molecules could have survived the 300C temperatures in volcanic vents, but Lynda Williams and her team at Arizona State University, found that lumps of clay that build up on the inside walls of the vents could have captured, then protected, key molecules for around six months. The clay deposits eventually break away and spill out onto the ocean floor, where they break open, releasing the molecules into cool surrounding waters.
Dr Williams’s group recreated the high temperature and pressure environment of a black smoker in the laboratory to examine whether organic molecules, the building blocks of life, could grow on various types of clay surface. “We simulated the reactants that we know can exist in black smoker environments, to see what organic compounds would form in nature,” she said. Six weeks into the experiment they discovered that a clay mineral helped organic molecules survive.
Not everyone, however, is convinced that Dr Williams’s work, which appeared in the journal Geology, properly explains how life on Earth got started. — Dawn/The Guardian News Service
Gates sees a ‘sea change’
The technology industry’s shift to internet-based software and services represents a massive and disruptive “sea change,” Microsoft Chairman Bill Gates wrote to top-level executives in a memo aimed at rallying his troops against the new competitive threats his company faces.
In an e-mail to top executives, dated Oct 30, Gates urged company leaders to “act quickly and decisively” to move further into the field of offering such services to best formidable competitors. But he also warned that the company must be thoughtful in building the right technology to serve the right audience.
“This coming ‘services wave’ will be very disruptive,” Gates wrote. “We have competitors who will seize on these approaches and challenge us — still, the opportunity to lead is very clear.”
Gates compares the push towards such services — including online business software offerings and free Web-based e-mail — to the changes he saw nearly a decade ago. — Dawn/LAT-WP News Service (c) Los Angeles Times
Data show seas in crisis
New historical data reveal that the world’s oceans are in crisis, largely due to overfishing — and they may not recover. The records indicate that the existing model for commercial fishing will exhaust fisheries in a decade or two.
“The oceans are dramatically different than they were 150 years ago,” said Poul Holm, a scientist with the Centre for Maritime and Regional Studies at the University of Southern Denmark. Back then, “there were many more top predatory fish like tuna, and nearly all fish were much larger... and found over wider areas than today,” Holm said.
Several hundred historians and marine scientists from around the world have been conducting research for more than five years into what the oceans were like 150, and even 300 years ago. They presented their findings recently at a conference in Norway.
Records revealed, for example, that the ling cod of the North Sea had been fished out before 1920, when the decline was previously believed to have started in the 1970s. — Dawn/IPS News Service
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