Further delay to Nasa's final Endeavour shuttle mission
The final mission of Nasa's Endeavour shuttle has been delayed further by a technical problem.
US space agency managers said the ship would not now lift off before 8 May.
It should have left Earth on Friday but has been held on the ground because of an electrical failure in a switchbox connected to a hydraulics power unit.
The youngest of America's reusable spaceplanes is set to deliver a $2bn (£1.2bn) particle physics experiment to the International Space Station (ISS).
On Sunday, Nasa announced the repairs would be lengthy but could not state precisely how long it would take to get the orbiter in a position to make another launch attempt.
"We can tell you pretty much that it's not going to be any earlier than the 8th," explained Mike Moses, the chair of the mission management team.
ISRO builds superfast supercomputer
ISRO on Monday announced it has built one of India’s fastest supercomputers with a theoritical peak performance of 220 trillion operations per second.
The 220 teraflops supercomputer “will be used by space scientists for solving complex aerospace problems,’’ ISRO said.The computer was fully designed and built at VSSC “using commercially available hardware, open source software components and in-house developments’’, ISRO said. It cost Rs 14 crore to build.
The phone with two brains that's a secret speed demon
A sight for sore eyes: The Sony Xperia Arc boasts a massive 4.2 inch screen, as well as a powerful dual-core processor
Bigger brains don't automatically mean higher intelligence -- otherwise the world would be ruled by the sperm whale, which tops the animal kingdom for sheer volume of grey matter.
It's what you do with it that counts.
That's the dilemma facing the new LG Optimus 2X mobile, which is the first on the market to boast a dual-core processor.
Dual cores have been common in computers for years but only now have the boffins conquered the technical hurdles to shrink the same technology into a mobile.
Essentially, it gives the device two brains and in theory makes everything run twice as fast.
The LG 2X looks not unlike many other premium Android phones, slickly designed and with a generously proportioned four-inch screen.
Light, yet solidly built, the 2X shows little outward sign of the horsepower under the bonnet.
Switch it on and it fairly zips along -- scrolling smoothly, launching apps in a trice and rarely pausing for breath.
But there's still a sense that nothing takes dramatic advantage of that extra oomph yet -- it's as if you were driving a Ferrari on an Offaly back road.
It may be the world's fastest phone but it feels only slightly nippier than single-core rivals.
But the 2X does have other tricks up its sleeve that make it worth recommending. The phone's big screen is impressive enough, delivering crisp and colourful visuals.
However, an HDMI port enables connection to a big-screen telly, all the better to show off the 2X's ultra-high-def video-camera footage, play games or simply to watch downloaded video.
Big ideas wanted for China's hi-tech revolution
Wu Lulu was once a farmer with no formal education. He built low-tech robots made out of any scrap he could get his hands on.
It did not always go smoothly. On one occasion, Mr Wu, 50, mistook detonators for batteries, blowing up his house and burning his face.But after more than two decades, his perseverance paid off.
He entered a TV competition for inventors - winning first prize, which included a cash purse.
His success ended the criticism of his neighbours who thought he should spend more time tending his crops and less time on his contraptions.
And now, Mr Wu has swapped his fields for a factory where he - and his team of 50 employees - design robots to order.
"I'm obsessed by building them," he says.
Viewpoint: What Bin Laden's death means for US policy
On a strategic level, Bin Laden's death could help mitigate the very sources of inspiration for Islamist terrorism, especially if no prominent figurehead emerges in his absence.
On the other hand, though, is the possibility that Bin Laden's narrative is sufficiently entrenched to make his death insignificant.
By this logic, al Qaeda's affiliates no longer rely on Bin Laden for symbolic inspiration, allowing them to continue to operate as before. This would be Bin Laden's lasting legacy.
Al-Qaeda's ambiguous, post-Bin Laden future has considerable implications for US counterterrorism policy.
Because Bin Laden's death will do little to change the tactical realities of Islamist terrorism, the operational dimensions of US policy should remain largely unchanged.
Ongoing efforts to target al Qaeda's regional affiliates will continue, and domestic law enforcement officials will continue to monitor and interdict emerging threats within the US.
Still, Bin Laden's death presents the Obama administration with an historic opportunity to puncture, once and for all, the toxic narrative that drives al-Qaeda's larger movement.
Richard Branson's lemur plan raises alarm
Sir Richard Branson is to import lemurs to the Caribbean, where they will live wild in the forest on his islands.
The project has alarmed conservation scientists, who point out that many previous species introductions have proved disastrous to native wildlife.But Sir Richard's team maintains that both the lemurs, which will come from zoos, and native animals will be fine.
Introducing species found on one continent into another for conservation purposes is virtually unprecedented.
Lemurs are found only on the African island of Madagascar and many species are threatened, largely because of deforestation.
The threat has grown worse since the toppling of President Marc Ravalomanana's government two years ago, which allowed illegal logging to flourish.
"We've been helping to try and preserve lemurs, and sadly in Madagascar because of the government being overthrown the space for lemurs is getting less and less," Sir Richard told BBC News from his Caribbean property.
"Here on Moskito Island we've got a beautiful rainforest - we brought in experts from South Africa, and they say it would be an absolutely perfect place where lemurs can be protected and breed."
Google denies Panda hit on rival
Google has defended recent changes to its search system that reduced the prominence of some popular websites.
One of the worst hit by the "Panda" update was Ciao.co.uk, a Microsoft-owned company that had been leading an EU competition case against Google.Its web visibility fell by 94% according to analysis by Searchmetrics.
Google's head of search evaluation, Scott Huffman, said it was "almost absurd" to suggest that the results were rigged.
The company regularly changes the algorithms that determine what users see when they search.
Rankings Such updates are often done to weed out "content farms" - websites that copy material from other sites in order to get hits.
Where a keyword search may previously have returned their site on Google's first page, afterwards it may be relegated to further down the rankings.
When the update, known as Panda, was rolled out globally on 11 April, Google published a blog post explaining that it was designed to "reduce rankings for low-quality sites".
Shopping and price comparison sites such as Ciao.co.uk sometimes suffer when Google algorithms change because they carry comments and reviews replicated elsewhere on the internet.
However, experts said that it was unusual to see a legitimate website hit as badly as Ciao.
"A 94% drop is astronomical," said Sanjay Shelat, a search engine optimisation (SEO) specialist at Edit Optimisation.
Air pollution 'damaging Europe's wildlife havens'
Air pollution is damaging 60% of Europe's prime wildlife sites in meadows, forests and heaths, according to a new report.
A team of EU scientists said nitrogen emissions from cars, factories and farming was threatening biodiversity.It's the second report this week warning of the on-going risks and threats linked to nitrogen pollution.
The Nitrogen Deposition and Natura 2000 report was published at a key scientific conference in Edinburgh.
Earlier this week, the European Nitrogen Assessment - the first of its kind - estimated nitrogen damage to health and the environment at between £55bn and £280bn a year in Europe, even though nitrogen pollution from vehicles and industry had dropped 30% over recent decades.
Nitrogen in the atmosphere is harmless in its inert state, but the report says reactive forms of nitrogen, largely produced by human activity, can be a menace to the natural world.
Some dinosaurs 'hunted at night'
The results suggests that small, meat-eating dinosaurs were nocturnal; large, plant-eating dinosaurs tended to forage both during the day and at night.
The Science study also challenges the notion that mammals' nocturnal nature evolved to avoid day-active dinosaurs.
Lars Schmitz and Ryosuke Motani of the University of California Davis have been looking at the eye parts of dinosaurs, and their modern-day descendants the lizards and birds, for a number of years.
They have been trying to determine just how big and how light-sensitive dinosaurs' eyes would have been.
That in turn would be an indication of whether they were active at night; until now the assumption has been that dinosaurs were diurnal, or primarily active in the daytime only.
Beer could be fresher for longer, says chemistry study
Scientists have identified the chemicals that lead to the bitter aftertaste of stale bottled beer.
Chemicals present in beer's hops break down over time, forming other compounds that result in the unpleasant taste.Researchers reporting in the Journal of Agricultural and Food Chemistry say the trick to avoiding the taste is to avoid that breakdown.
That can be done by adjusting beers' acidity when it is produced, and by always keeping it cool.
The idea that the naturally-present, slightly bitter-tasting compounds are the source of the more bitter, more long-lasting flavours of "aged" beer is not new.
But the exact catalogue of compounds that are responsible and how they develop over time has remained a mystery until now.
Japan nuclear operator to pay compensation to evacuees
About 48,000 families who lived within 30km (18 miles) of the Fukushima Daiichi plant will be eligible.
The compensation is described as provisional, with more details to be announced later in the day.
The plant operator, Tepco, is still trying to stabilise the nuclear facility.
"Tokyo Electric Company (Tepco) is to make an urgent and speedy payment in order to compensate for the losses incurred by evacuation and orders to stay indoors," said chief government spokesman Yukio Edano.
"The basic idea is that one household will receive 1 million yen ($12,000, £7,331). We think that such an amount is necessary as a provisional payment," he said.
The BBC's correspondent in Tokyo, Roland Buerk, says the payments are the first of what is likely to be a massive compensation bill.
JP Morgan has estimated Tepco may face claims of up to 2 trillion yen, nearly $24bn (£15bn) by the end of this year.
Malaysia teacher charged with murdering schoolboy
A Malaysian school teacher has been charged with the murder of a seven-year-old student at a private Islamic school in the northern state of Perlis.
The schoolboy was accused of stealing a couple of dollars from a classmate. As punishment, the boy was allegedly tied up to a window, caned and beaten for two hours. He fell into a coma and died in hospital three days later.
The boy's death has caused public outrage with the deputy prime minister calling the case unforgivable.
Prosecutors charged a 26-year-old school teacher with murder but he did not enter a plea.
If convicted he could face the death penalty, which is carried out by hanging.
His lawyer asked the court to restrict media coverage of the case, but the judge refused.
This is believed to be the worst case of student abuse in the country.
Humpback whale song spreads to other whales
Recordings of male humpback whales have shown that their haunting songs spread through the ocean to other whales.
Researchers in Australia listened to hundreds of hours of recordings gathered over more than a decade. These revealed how a specific song pattern, which originated in Eastern Australia, had passed "like Chinese whispers" to whale populations up to 6,000km away in French Polynesia.
The findings are reported in the journal Current Biology.
