very nice biomimicy research - we should try to see if we can't apply this also to landing spacecraft!!

A miniature robotic helicopter has revealed a simple yet effective visual trick that lets insects fly so adeptly without sophisticated avionics.

Besides explaining how insects zoom around and land without crashing into the ground, the technique could potentially be used to help control aircraft.

As insects fly forwards the ground beneath them sweeps backwards through their field of view. This "optical flow" is thought to provide crucial cues about speed and height. For example, the higher an insect's altitude, the slower the optical flow; the faster it flies, the faster the optical flow.

Previous experiments involving bees suggest that optical flow is crucial to landing. Maintaining a constant optical flow while descending should provide a constant height-to-groundspeed ratio, which makes a bee slowdown as it approaches the ground. Distorting this optical flow can cause them to crash land instead.

General flight

Now Nicolas Franceschini at the University of the Mediterranean in Marseilles, France, and colleagues have shown the same technique may explain more general flying behaviours.

They fitted a miniature helicopter with a simple software feedback loop to ensure that optical flow remains constant as it flies along. This allowed the tethered micro-copter to take off gracefully, maintain altitude over varying terrain and land, all without any means of directly measuring its speed or height. A video produced by the researchers shows the micro-copter in action (43.7 MB .avi format, requires DivX).

The fact that insects are such effective fliers could all be thanks to a similar feedback mechanism hardwired into their brains, Franceschini says.

Bee brains

Maintaining a constant optical flow should be relatively easy for an insect, says Rob Harris, a specialist in insect vision at the Centre for Computational Neuroscience and Robotics and the University of Sussex, in Brighton, UK, who was not involved with the project.

Maintaining a constant optical flow precludes the need to calculate height and groundspeed manually. "You have to assume they are not doing complicated trigonometry in their little brains," he adds.

"It explains about 70 years of experiments," Franceschini says. For example, it explains why bees sometimes drown when flying over still water. Without any features on the surface of water, a bee detects no optical flow and instinctively descends, eventually landing in the water.

Franceschini is currently talking to helicopter manufacturers about developing optical flow regulators for their aircraft. Such feedback mechanisms would be lightweight and trivial to develop and could help prevent crashes, he claims.

Journal reference: Current Biology (vol 17, issue 4, manuscript 5340)

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New prize by Branson for a method to remove CO2 from the atmosphere ... start using your brains!

A prize of $25 million for anyone who can come up with a system for removing greenhouse gases from the atmosphere was launched on Friday. It is the biggest prize in history, claims its sponsor, Richard Branson.

The head of Virgin Group said at the launch in London, UK, that the prize was not for removing emissions from power plants before they reach the atmosphere and storing them deep underground – an existing technology known as carbon capture and sequestration.

Instead, the brief is to devise a system to remove a "significant amount" of greenhouse gases – equivalent to 1 billion tonnes of carbon dioxide or more – every year from the atmosphere for at least a decade. It was inspired by the £20,000 prize for developing a way of measuring longitude won by 18^th century clockmaker John Harrison, and recounted in the book Longitude. The $10 million X-Prize for private human spaceflight, won in 2004, was also an inspiration.

The initial closing date for Branson's Earth Challenge is 8 February 2010. If the judges deem that no design submitted by that stage is worthy of the prize, it will re-open for two more year-long phases.

$25 million prize for greenhouse gas removal - earth - 09 February 2007 - New Scientist Environment

lets win this prize :-)

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The brain scan that can read people's intentions (The Guardian)

A team of world-leading neuroscientists has developed a powerful technique that allows them to look deep inside a person's brain and read their intentions before they act.

The brain scan that can read people's intentions | Science | Guardian Unlimited

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US climate scientists pressured on climate change

* 15:01 31 January 2007

* NewScientist.com news service

* New Scientist Environment and Reuters



US scientists were pressured to tailor their reports on global warming to fit the Bush administration's climate change scepticism, a congressional committee heard on Tuesday 30 January. In some cases, this occurred at the request of a former oil-industry lobbyist.

"High-quality science [is] struggling to get out," Francesca Grifo, of the watchdog group Union of Concerned Scientists, told members of the House Oversight and Government Reform Committee. A UCS survey found that 150 climate scientists personally experienced political interference in the past five years in a total of at least 435 incidents.

"Nearly half of all respondents perceived or personally experienced pressure to eliminate the words 'climate change', 'global warming' or other similar terms from a variety of communications," Grifo said.

Rick Piltz, a former US government scientist, told the committee that former White House official Phil Cooney took an active role in casting doubt on the consequences of global climate change. Piltz said he resigned in 2005 as a result of pressure to soft-pedal findings on global warming.

Cooney, who was a lobbyist for the American Petroleum Institute before becoming chief of staff at the White House Council on Environmental Quality, also resigned in 2005. He went on to work for oil giant ExxonMobil, which was recently accused of spending $16 million on supporting climate sceptics.



"Speculative musing"

Documents on global climate change required Cooney's review and approval, Piltz said, adding that "If you know what you are writing has to go through a White House clearance before it is to be published, […] an anticipatory kind of self-censorship sets in."

He added: "[Cooney's] edits of programme reports, which had been drafted and approved by career science programme managers, had the cumulative effect of adding an enhanced sense of scientific uncertainty about global warming and minimising its likely consequences."

According to The Guardian newspaper, Piltz described how Cooney had personally edited out a key section of an Environmental Protection Agency report to Congress on the dangers of climate change, calling it "speculative musing".



Seeking answers

Henry Waxman, a California Democrat who chairs the oversight committee, complained that the White House has balked at supplying documents requested over six months to investigate these allegations.

"The committee isn't trying to obtain state secrets or documents that could affect our immediate national security," Waxman said. "We are simply seeking answers to whether the White House's political staff is inappropriately censoring impartial government scientists."

Kristen Hellmer, of the Council on Environmental Quality, part of the Executive Office of the US President, said the CEQ had been cooperating with Congress. When asked about allegations of political interference in scientific documents, she said: "We do have in place a very transparent system in science reporting."



Spate of accusations

Reporting on the hearing, the New York Times says that even Republicans had little good to say of the Bush administration's handling of climate change science. Almost all the Republicans on the panel began by stating that global warming was happening and that greenhouse gases from human activities were largely to blame.

The Bush administration has suffered a spate of accusations of muzzling climate scientists in recent years. In January 2006, James Hansen, director of the US space agency's Goddard Institute for Space Studies, said that officials at NASA headquarters had ordered their staff to review his lectures, papers, postings on the Goddard website and requests for media interviews (see Top climatologist accuses US of trying to gag him).

In February 2006, the topic was brought up in the House Committee on Science, and New Scientist reported that scientists at another government agency, the National Oceanic and Atmospheric Administration, were also upset about the situation.

The UCS issued its first accusations in February 2004, followed closely by more finger pointing in July of that year.



Mandatory limits

President George W Bush's position on global warming has evolved over his presidency, from open scepticism about the reality of the phenomenon to acknowledgment at a global summit in 2006 that climate change is occurring and that human activities speed it up.

In his 2007 State of the Union address, Bush called climate change "a serious challenge" that should be addressed by technology and greater use of alternative sources of energy. But he stopped short of calling for mandatory limits on US emissions of carbon dioxide, a greenhouse gas blamed in part for global warming.

The congressional discussions come in the run-up to the release of a major United Nations report on climate change, scheduled for Friday in Paris, France.

Leaked drafts of the report suggest it will state that "there is a 90% chance humans are responsible for climate change", mostly due to the burning of fossil fuels. That contrasts with the last version of the Intergovernmental Panel on Climate Change's report, issued in 2001, which concluded there was a 66% chance that humans were responsible for rising temperatures.

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The quantum world is about to get bigger

The quantum world is about to get bigger thanks to a technique that
will allow objects big enough to see with the naked eye to exist in two
places at once.

Quantum
properties are most prominent in single particles. In bigger objects
thermal vibrations destroy the quantum effects. So in theory, chilling
a large object should allow its quantum properties to shine through.

This week, three teams of physicists have perfected a way of doing this (Nature, vol 444, p 67). Their technique is to bombard a mirror of roughly 10¹⁴ atoms with photons in a way that damps out thermal vibrations, cooling it to 135 millikelvin.

However,
the researchers will need sophisticated techniques to see the quantum
behaviour. "You can see the mirror with the naked eye but you won't be
able to resolve the quantum effects," says Markus Aspelmeyer, at the
University of Vienna in Austria.

Of course, you won't be. If you were, you would be a measuring device and according to the laws of quantum mechanics the quantum effect should disappear (decoherence and in the end collapse of the wave function.) So in the end it is not a question of size!

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