Thursday, June 12, 2008

Ares 1x-V2.1 Test Flight

First-ever multi-person space vacation confirmed for 2011

The company that's lofted customers to the International Space Station on five separate occasions announced today that it will launch the first private multi-person mission to the ISS in the second half of 2011.

Space Adventures announced that the 2011 flight will be a fully dedicated mission, with two Russian Soyuz-TMA spacecraft seats available for private space explorers.

Previous single-space-tourist flights have cost a reported $20 million US.

Seats used for something besides people?
The first full-blown private "mission" to the ISS (as opposed to single paying customers tagging along in seats on missions earmarked for space station construction) will be offered to businesses, organizations, and institutions, as well as individual explorers.

"For the last decade, Space Adventures' orbital spaceflight program has provided the only opportunity for private individuals to fly in space, conduct research in a sustained zero gravity environment and experience the beauty of seeing the Earth from humanity's only orbiting outpost," said Eric Anderson, president and CEO of Space Adventures.

Space Adventures first grabbed headlines in 2001 when it brokered the launch of business tycoon Dennis Tito, the world's first privately funded spaceflight participant.

Google in spaaaace...
Google co-founder Sergey Brin is hoping to buy one of the seats on the 2011 flight.

As well, Space Adventures' sixth orbital spaceflight client, video game designer Richard Garriott, son of NASA astronaut Owen Garriott, is currently in cosmonaut training with his launch to the ISS scheduled for October 12, 2008.

"We are very pleased to continue working with Space Adventures into the foreseeable future. This method for growing our commercial partnership with Space Adventures is beneficial for all parties. The Soyuz to be used for this mission shall be a specially manufactured craft, separate from the other Soyuz vehicles designated for the transportation of the ISS crews," said Alexey B. Krasnov, FSA. "This private mission, flying two Space Adventures' clients at once, will not interfere with the implementation of the ISS program or the obligations of the Russian space agency; on the contrary, it shall add flexibility and redundancy to our ISS transportation capabilities."

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Plutoid chosen as name for solar system objects like Pluto

The two known and named plutoids are Pluto and Eris. Plutoids are celestial bodies in orbit around the Sun at a distance greater than that of Neptune that have sufficient mass for their self-gravity to overcome rigid body forces so that they assume a ...
The two known and named plutoids are Pluto and Eris. Plutoids are celestial bodies in orbit around the Sun at a distance greater than that of Neptune that have sufficient mass for their self-gravity to overcome rigid body forces so that they assume a hydrostatic equilibrium (near-spherical) shape, and that have not cleared the neighbourhood around their orbit. Credit: IAU, NASA/ESA Hubble Space Telescope, H. Weaver (JHU/APL), A. Stern (SwRI), the HST Pluto Companion Search Team and M. Brown
Almost two years after the International Astronomical Union (IAU) General Assembly introduced the category of dwarf planets, the IAU, as promised, has decided on a name for transneptunian dwarf planets similar to Pluto. The name plutoid was proposed by the members of the IAU Committee on Small Body Nomenclature (CSBN), accepted by the Board of Division III, by the IAU Working Group for Planetary System Nomenclature (WGPSN) and approved by the IAU Executive Committee at its recent meeting in Oslo, Norway.

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Plutoids are celestial bodies in orbit around the Sun at a distance greater than that of Neptune that have sufficient mass for their self-gravity to overcome rigid body forces so that they assume a hydrostatic equilibrium (near-spherical) shape, and that have not cleared the neighbourhood around their orbit. The two known and named plutoids are Pluto and Eris. It is expected that more plutoids will be named as science progresses and new discoveries are made.

The dwarf planet Ceres is not a plutoid as it is located in the asteroid belt between Mars and Jupiter. Current scientific knowledge lends credence to the belief that Ceres is the only object of its kind. Therefore, a separate category of Ceres-like dwarf planets will not be proposed at this time.

The IAU has been responsible for naming planetary bodies and their satellites since the early 1900s. The IAU CSBN, who originally proposed the term plutoid, is responsible for naming small bodies (except satellites of the major planets) in the Solar System. The CSBN will be working with the IAU WGPSN to determine the names of new plutoids to ensure that no dwarf planet shares the name of another small Solar System body. The WGPSN oversees the assignment of names to surface features on bodies in the Solar System. These two committees have previously worked together to accept the names of dwarf planet Eris and its satellite Dysnomia.
In Oslo, members of the IAU also discussed the timing involved with the naming of new plutoids. Again, following the advice of the Division III Board and the two Working Groups, it was decided that, for naming purposes, any Solar System body having (a) a semimajor axis greater than that of Neptune, and (b) an absolute magnitude brighter than H = +1 magnitude will be considered to be a plutoid, and be named by the WGPSN and the CSBN. Name(s) proposed by the discovery team(s) will be given deference. If further investigations show that the object is not massive enough and does not qualify as a plutoid, it will keep its name but change category.

In French plutoid is plutoïde, in Spanish plutoide.

Source: International Astronomical Union

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McCain would like to see a man on Mars

NASA image taken by the Viking Orbiter shows canyons and volcanoes on the surface of Mars. Republican presidential candidate John McCain says he would like to see a manned mission to Mars as part of a "better set of priorities" for NASA that would better engage the public.(AFP/NASA/File/Michael Benson)
AFP/NASA/File Photo: NASA image taken by the Viking Orbiter shows canyons and volcanoes on the surface of...

WASHINGTON (AFP) - Presumptive Republican White House nominee John McCain said Thursday he would like to see a manned mission to Mars as part of a "better set of priorities" for NASA that would better engage the public.

At a townhall event in Florida, the Arizona senator was asked about funding for the US space agency's shuttle program, which is due to end in 2010.

He said he "would be willing to spend more taxpayers' dollars" to continue the program but argued that NASA must do a better job of inspiring the American public, as when it sent a man to the moon in 1969.

McCain said one of his favorite books as a child had been Ray Bradbury's 1950 novel "The Martian Chronicles," about humans colonizing the Red Planet.

"I am intrigued by a man on Mars and I think that it would excite the imagination of the American people if we can say, 'Hey, here's what it looks like," he said.

"We know that now, and here's what may be there and let's all join in that project. I think Americans would be very willing to do that."

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Experimental Alzheimer's drug is 'astonishing'

An experimental treatment for Alzheimer's has been found to have a novel way of working that offers the hope of new, more effective, drugs to combat this devastating form of dementia.

Alzheimer's affects one in 20 of those over 65, causing loss of memory, personality changes and, eventually, death.

A hallmark of Alzheimer's, along with diseases such as variant CJD, is the formation of "plaques" composed of clumps of protein, which are believed to damage brain cells.

Now a drug has been found to cut the production of one protein fragment that is prone to build up and stop these fragments from clumping by several separate mechanisms.

What excites neuroscientists is that the drugs, called GSMs, work in a way that has not been seen before, on the protein rather than the enzyme that makes the proteins that form the clumps.

This, says one commentator, is "an astonishing result".

The team - which number 29, from four nations - is led by Prof Todd Golde, Department of Neuroscience at Mayo Clinic in Jacksonville.

In the journal Nature, they report that agents known as gamma-secretase modulators (GSM) work to reduce production of long pieces of the amyloid beta protein (Abeta) that readily stick together and form clumps, and increase production of shorter pieces of the same protein that can inhibit the longer forms from sticking together.

Although the GSM's alter enzyme activity that produces the protein that forms the clumps, now it seems they also act on the amyloid beta itself.

"The action might be analogous to some cholesterol lowering drugs that can lower LDL, the bad cholesterol that sticks to your arteries, and can raise HDL, the good cholesterol that sweeps out LDL," says Prof Golde, who did the work with Dr Thomas Kukar.

"This broadens the notion of what drugs can do, and therefore, has wide reaching implication for future drug discovery for many different disorders," Dr Golde says.

The findings also suggest that GSMs now being tested or in development to treat Alzheimer's may prove to be valuable, the researchers say. One such drug, tarenflurbil (Flurizan), is in Phase III clinical trials, and results from the first, a 1,600-patient US study, are expected this summer.

Results of a phase II study, published online in April in Lancet Neurology, suggest it provides benefit in patients with mild Alzheimer's, Dr Golde says.

Until the Mayo Clinic study, it was not understood that tarenflurbil was a GSM and it was being tested (unsucessfully) to treat prostate cancer.

But then cell and animal studies suggested that tarenflurbil could affect protein clumps linked with Alzheimer's and reduce cognitive deficits in mice with a form of the disease.

"If results from tarenflurbil and other GSM agents are less beneficial than hoped, these findings may help drug designers create newer, more potent drugs," Dr Golde says. "Anytime we gain an increased understanding of the precise molecular action of a drug, that enhances our ability to make better drugs."

By further studies to understand how these agents work to prevent protein build up, the team can then sit down to design more potent versions.

However, Dr Kukar tells the Telegraph: "Next generation GSMs based on this research will likely take years to get in the clinic."

He adds that the find could apply to other diseases marked by protein deposits, notably "human BSE," vCJD.

Study co-authors include researchers from the Swiss Federal Institute of Technology in Lausanne, Switzerland; Harvard Medical School; the Technische Universitaet in Darmstadt, Germany, University College in Dublin, Ireland; and the University of California at San Diego.

Prof Clive Ballard, the director of research at the Alzheimer's Society, said: "This will provide important opportunities to develop clinically effective drugs.

"However, clinical trials are extremely expensive and a large increase in investment in dementia research is drastically needed to turn these exciting scientific discoveries into new treatments."

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Amazing Robo-Fish Work Together

One of three fin-propelled Robofish was designed to wirelessly communicate with other robotic fish. The robot is about the size of a 10-pound salmon (penny shown to give a sense of Robofish size). Credit: University of Washington.

A trio of robotic fish sporting tails and fins recently aced their first swim team test.

While most underwater robots rely on guidance from a scientist or satellite, the new robots, called Robofish, can work as a team by wirelessly communicating only with each other.

Kristi Morgansen, an aeronautics and astronautics engineer at the University of Washington, presented results from this swim test at the International Federation of Automatic Control's Workshop on Navigation, Guidance and Control of Underwater Vehicles.

The fish are about two feet long and wiggle through the water by using their fish-like tails and fins. The researchers say fins have advantages over propellers that are commonly used for underwater robots, in that fins produce less drag and noise, and allow the robots to make tight turns.

In the future, Morgansen and her colleagues say schools of ocean-going robots could work together to track groups of the real McCoy underwater, such as whales or dolphins (though these marine species are actually mammals, not fish), or even explore hard-to-reach caves, such as those tucked beneath ice.

In the lab, Morgansen and her colleagues programmed the robo-fish to either swim in the same direction or in different directions (in the latter case, each one would swim about 120 degrees from its neighbor).

Here's how the robots "talk" to each other: "One of them will send a message, and the rest of them know it's not their turn to talk and so they are listening," Morgansen told LiveScience. "There's a time during which they know there is a signal coming. If they receive it, they use it; if they don't, they keep following what they were doing."

For instance, if the robotic fish are programmed to collect information in areas where "lots of things are happening," Morgansen said, "you don't want all of them to go to same place."

With three coordinated robots, they can relay their locality to teammates and signal the others to collect information at another "happening" spot.

"If you have some sort of event going on like an underwater eruption, you're not going to be able to get one vehicle to a bunch of places quickly," Morgansen said. And so the more underwater researchers, the better, as long as they don't all flock to the same location.

Next, Morgansen said she will test the teamwork of the three Robofish in a task more similar to what they would face in the ocean: The fishy robots will trail a remote-controlled toy shark.

The research was supported by grants from the National Science Foundation and the Air Force Office of Scientific Research.

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'Electron turbine' could print designer molecules

A carbon nanotube that spins in a current of electrons, like a wind turbine in a breeze, could become the world's smallest printer or shrink computer memory, UK researchers say.

The design is simple. A carbon nanotube 10 nanometres long and 1 nm wide is suspended between two others, its ends nested inside them to form a rotating joint. When a direct current is passed along the tubes, the central one spins around.

That design has as yet only been tested using advanced computer simulations by Colin Lambert and colleagues at Lancaster University, Lancashire, UK.

But Adrian Bachtold of the Catalan Institute for Nanotechnology, who was not involved in the work, intends to build the electron turbines and says it should be straightforward.

Researchers have made or designed a range of small-scale motors in recent years, using everything from DNA to light sensitive molecules to cell-transport proteins.

The Lancaster design is one of the simplest yet. Imagined applications for nanomotors range from shrinking optical communications components to new forms of computer memory.

Tiny turbine

Conventional water or wind turbines spin by deflecting oncoming air or water in one direction. This causes a reaction force to push them in the opposite direction.

Similarly, when electrons move through the nanotube turbine, they tend to bounce off its spiral arrangement of carbon rings in a particular direction. This redirects the electrons into a spiral flow, and causes the tube to rotate in the opposite direction.

The Lancaster team is confident this electron "wind" can overcome any friction forces that would prevent the middle tube spinning. They also hope to minimise friction at the joints by making the nanotubes as smooth as possible.

Tiny inkjet

The Lancaster researchers say their motor could be used to pump atoms and molecules through the spinning middle tube. Multiple pumps could precisely control a chemical reaction, driving atoms in a pattern to engineer new molecules. "It's like a nanoscale inkjet printer," says Lambert.

Atoms pumped through the motor could also be used to represent digital data, with an array of motors shuttling atoms between the 1 and 0 ends of the middle tube to store or process information. This method could store data in a space about 10 times smaller than today's state-of-the-art commercial systems, says Lambert.

"The work of Lambert's group is exciting," says Bachtold, "the proposed motors should be rather straightforward to fabricate". But he points out that only experiments will reveal whether this new nanomotor design lives up to its promise.

A paper on the electron windmills will be published in Physical Review Letters this month. A pre-review version is available on the arXiv pre-print website.

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The Sunspot Enigma: The Sun is “Dead”—What Does it Mean for Earth?

Dark spots, some as large as 50,000 miles in diameter, typically move across the surface of the sun, contracting and expanding as they go. These strange and powerful phenomena are known as sunspots, but now they are all gone. Not even solar physicists know why it’s happening and what this odd solar silence might be indicating for our future.

Although periods of inactivity are normal for the sun, this current period has gone on much longer than usual and scientists are starting to worry—at least a little bit. Recently 100 scientists from Europe, Asia, Latin America, Africa and North America gathered to discuss the issue at an international solar conference at Montana State University. Today's sun is as inactive as it was two years ago, and solar physicists don’t have a clue as to why.

"It continues to be dead," said Saku Tsuneta with the National Astronomical Observatory of Japan, program manager for the Hinode solar mission, noting that it is at least a little bit worrisome for scientists.

Dana Longcope, a solar physicist at MSU, said the sun usually operates on an 11-year cycle with maximum activity occurring in the middle of the cycle. The last cycle reached its peak in 2001 and is believed to be just ending now, Longcope said. The next cycle is just beginning and is expected to reach its peak sometime around 2012. But so far nothing is happening.

"It's a dead face," Tsuneta said of the sun's appearance.

Tsuneta said solar physicists aren't weather forecasters and they can't predict the future. They do have the ability to observe, however, and they have observed a longer-than-normal period of solar inactivity. In the past, they observed that the sun once went 50 years without producing sunspots. That period coincided with a little ice age on Earth that lasted from 1650 to 1700. Coincidence? Some scientists say it was, but many worry that it wasn’t.

Geophysicist Phil Chapman, the first Australian to become an astronaut with NASA, said pictures from the US Solar and Heliospheric Observatory also show that there are currently no spots on the sun. He also noted that the world cooled quickly between January last year and January this year, by about 0.7C.

"This is the fastest temperature change in the instrumental record, and it puts us back to where we were in 1930," Dr Chapman noted in The Australian today.

If the world does face another mini Ice Age, it could come without warning. Evidence for abrupt climate change is readily found in ice cores taken from Greenland and Antarctica. One of the best known examples of such an event is the Younger Dryas cooling, which occurred about 12,000 years ago, named after the arctic wildflower found in northern European sediments. This event began and ended rather abruptly, and for its entire 1000 year duration the North Atlantic region was about 5°C colder. Could something like this happen again? There’s no way to tell, and because the changes can happen all within one decade—we might not even see it coming.

The Younger Dryas occurred at a time when orbital forcing should have continued to drive climate to the present warm state. The unexplained phenomenon has been the topic of much intense scientific debate, as well as other millennial scale events.

Now this 11-year low in Sunspot activity has raised fears among a small but growing number of scientists that rather than getting warmer, the Earth could possibly be about to return to another cooling period. The idea is especially intriguing considering that most of the world is in preparation for global warming.

Canadian scientist Kenneth Tapping of the National Research Council has also noted that solar activity has entered into an unusually inactive phase, but what that means—if anything—is still anyone’s guess. Another solar scientist, Oleg Sorokhtin, a fellow of the Russian Academy of Natural Sciences, however, is certain that it’s an indication of a coming cooling period.

Sorokhtin believes that a lack of sunspots does indicate a coming cooling period based on certain past trends and early records. In fact, he calls manmade climate change "a drop in the bucket" compared to the fierce and abrupt cold that can potentially be brought on by inactive solar phases.

Sorokhtin’s advice: "Stock up on fur coats"…just in case.

Posted by Rebecca Sato

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Early Humans Experimented To Get Bow And Arrow Just Right, Findings Suggest

Arrow points (top) were reworked and refined through experimentation, often using dart points (bottom) as a starting place. The difference between the two types of points (size and neck/stem width) can be observed in this photo. (Credit: University of Missouri)

In today's fast-paced, technologically advanced world, people often take the innovation of new technology for granted without giving much thought to the trial-and-error experimentation that makes technology useful in everyday life. When the "cutting-edge" technology of the bow and arrow was introduced to the world, it changed the way humans hunted and fought. University of Missouri archaeologists have discovered that early man, on the way to perfecting the performance of this new weapon, engaged in experimental research, producing a great variety of projectile points in the quest for the best, most effective system.

"Technological innovation and change has become a topic that interests people," said R. Lee Lyman, professor and chair of the University of Missouri Department of Anthropology. "When the bow and arrow appeared in North America, roughly 1,500 years ago, it eventually replaced the atlatl (spear thrower) and dart. The introduction of the bow and arrow, a different weapon delivery system, demanded some innovative thinking and technology. In other words, one could not just shoot a dart from a bow. Components like the shaft and arrow point needed to be reinvented."

Because the necessary flight dynamics and mechanics of the arrow wouldn't have been fully understood, the indigenous people at the time would have experimented--trying all sorts of points with different types of shafts, attempting to discover the best combinations. This reinvention process can be seen archaeologically through an increase in the number and variation of projectile points--indicating the transition period between the atlatl and the bow and arrow.

"Everyone is looking for the better mouse trap," Lyman said. "Once a change is made in one variable, it may prompt changes in another variable because the two are mechanically linked. For example, if something gets longer, generally, it will get heavier. This is called a cascade effect. This, in combination with experimentation, resulted in the tremendous variation in projectile points."

Lyman said there is evidence of an initial burst of variation in projectile points at the time bow-and-arrow technology was introduced and that prehistoric artisans experimentally sought arrow points that worked effectively. Following that initial burst, less-effective projectile models were discarded, causing archaeologists to see a reduction in variation.

In the course of this research, Lyman and his collaborators, T.L VanPool and M.J. O'Brien, analyzed the data from more than 1,000 projectile points from three separate geographical locations. Lyman's study, "Variation in North American dart points and arrow points when one, or both are present," will be published in an issue of the Journal of Archaeological Science in fall 2008.

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Curious 'quasiparticles' baffle physicists

Quasiparticle test

Fractionally charged: An illustration of the experimental set-up with extremely pure gallium arsenide. Quasiparticles, shown in yellow, travel along the edge and have one quarter the charge of an electron.

Credit: Genia Brodsky, Weizmann Institute.

SYDNEY: Israeli physicists have discovered bizarre 'quasiparticles' which have one quarter the charge of an electron, and may be useful in quantum computing.

Quasiparticles are formed within a group of electrons and behave as if they are particles. But they only have a fraction of the charge of an electron, according to lead researcher Merav Dolev from the Weizmann Institute of Science in Israel, who announced the discovery this week. This is weird because no single particle can have a fraction of electric charge.

Electron soup

Until now, researchers have only been able to form quasiparticles with one-third, one-fifth or one-seventh of the charge on an electron. Quasiparticles with even denominators, such as one-quarter or one-sixth, are expected to behave completely differently to quasiparticles with odd denominators.

In this study, the researchers trapped a 'soup' of electrons in an extremely pure sample of gallium arsenide, so that the electrons could only move in two directions – that is, they could move forward and backward, and side to side, but not up and down. As they also reported in a paper in the British journal Nature earlier this year, they then placed this sample in a magnetic field.

In this precise set-up, with the extremely pure gallium arsenide, researchers could see these quarter-charged quasiparticles.

It's the quasiparticles with even denominators, such as one-quarter, that are more interesting, because scientists expect the order in which they interact changes the outcome. So, if you switch quasiparticle A with quasiparticle B, then switch B with C, it is not the same as switching B with C then A with B.

"[This] is very non-intuitive," said Dolev. "All of the 'regular' particles – which is what we are used to – do not behave like that." Quasiparticles with odd denominations of electron charge do not share this curious behaviour.

The outcome is that a quasiparticle can 'remember' the path it has taken. Dolev expects this property to be exploited in an exotic type of quantum computer called a 'topological quantum computer'.

The computing would be done "by rotating quasiparticles, one around the other." Dolev said. "All you care about, then, is which quasiparticle went around which, not the exact path. This is what makes it 'topological', since you only care about the topology of the path."

Robust qubits

All computing is based on strings of bits, where a bit can take the value 1 or 0. Currently, this is done by transistors. But in a quantum computer (see, Seeking a quantum computing breakthrough, Cosmos Online), the bits would be made from particles that are linked together by quantum behaviour. These are termed 'qubits' or quantum bits. In topological quantum computers a bit could be made from two quasiparticles.

In other types of quantum computing, for example linking quantum bits with lasers, the system is strongly affected by its environment. An ever-so-slight movement stops the system from working. But because of the path of these quasiparticles is not important, a topological quantum computer would be much more robust.

"The possibility of producing a topologically based quantum computer based on these quasiparticles is interesting," commented physicist Jeff McCallum, from the University of Melbourne. "[But] there is plenty of room for more competitors in the quantum computer race and there is no clear winner in the field yet."

Scientists predict the first quantum computer may be here in less than 20 years and would be many times more powerful than modern supercomputers, rapidly solving problems that would otherwise take many years to complete.

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SF Passes Largest City Solar Program in U.S. (Finally)

After six months of hard-fought politicking, the San Francisco board of supervisors has finally approved the Solar Energy Incentive Program, the country’s largest municipal solar program. The program has been greenlighted for 10 years and has an annual budget of $3 million dollars. The money will be doled out as rebates in the form of tax incentives for private solar installations. Now the ordinance just needs approval from Mayor Newsom, who has been pushing for this program; it’s expected that the solar energy incentive program will be operational in the coming weeks. Update: For our interview with Mayor Newsom this afternoon, read here. He’s expecting the solar program to be ready as early as July 1st.

The program is designed to reduce the cost of solar for city residents and leverage private dollars to get more solar on San Franciscans’ roofs. Local solar installers, including Sun Run, Akeena Solar and SolarCity all made appearances throughout the lengthy six-month proceedings to voice their approval of the program, explaining it would provide jobs and clean power for the foggy city. Now the installers can start including the large new rebates, which can cut the cost of going solar by 20 percent, in their promotional materials and cost estimates.

The program grants a $3,000 to $6,000 rebate to individuals and a $10,000 rebate to businesses on solar installations. The board also preliminarily passed a separate $1.5 million one-year pilot program aimed specifically at helping low-income San Franciscans and nonprofits. This proposal still needs to be approved on a final read by the board, but it could mean the city will be paying out $4.5 million for solar roofs by the year’s end.

The city hopes that the $3 million in public funding will leverage some $1.5 million in private investment to boost the city’s solar capacity to 55 megawatts on some 15,000 rooftops over the next 10 years. Currently there are fewer than 700 solar rooftops in the city generating less than 5 megawatts of power.

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New Zealand faces power crisis amid drought

Helen Clark: 'it's not an emergency.' Photograph: Adrian Dennis/AFP

New Zealanders are to be urged to wash dishes by hand and turn off lights as the country teeters on the brink of a power crisis caused by drought.

After two years of dry weather, the level of water in lakes that drive New Zealand's hydroelectric power plants is worryingly low.

The energy minister, David Parker, denied claims the country was facing rolling power cuts but said households would be asked to cut electricity consumption by up to 15% during peak early evening periods unless there was "significant" rainfall soon.

Hydroelectric stations usually produce about 75% of New Zealand's electricity but a lack of rain has reduced that output in recent weeks to 50%. Coal, diesel and gas-fired power plants are trying to make up the shortfall, but more strain is expected to be put on the national grid with the arrival of winter in the southern hemisphere.

Backed by the government, the electricity industry is to launch a TV campaign aimed at domestic, commercial and industrial users.

The prime minister, Helen Clark, said: "I think the advice will be that while it's not an emergency, it is time for people to be turning off lights in rooms they are not using, certainly not leaving the computer on all night, the heated towel rail not on for 24 hours a day."

The last time there was a serious power shortage in New Zealand was in 1992 when businesses were forced to use liquid petroleum gas and diesel. Street lighting was rationed and households endured hot water restrictions.

The public was also asked to save power in 2001, 2003 and 2006 but each time rain came soon enough to head off any serious problems.

Phil O'Reilly, the chief executive of Business New Zealand, said poor decisions by successive governments had led to New Zealanders living with the threat of electricity shortages. "You just can't run an economy like this," he said.

"If we get through to the end of winter without blackouts; it was all done by the skin of our teeth. I don't think that's a sensible proposition."

Clark said the commissioning of a new geothermal plant was being brought forward and industrial users of electricity were being targeted to see if they could ease back on demand. "A lot of things are being done to make sure that we move through this dry spell as smoothly as we can," she said.

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