'Sunspot numbers are well below their values from 2011, and strong solar flares have been infrequent,' the space agency says. Experts have been baffled by the apparent lack of activity - with many wondering if NASA simply got it wrong.

However, Solar physicist Dean Pesnell of NASA’s Goddard Space Flight Center believes he has a different explanation. 'This is solar maximum,' he says. 'But it looks different from what we expected because it is double-peaked. The last two solar maxima, around 1989 and 2001, had not one but two peaks.'

The same thing could be happening now, as sunspot counts jumped in 2011 and dipped in 2012, he believes. Pesnell expects them to rebound in 2013: 'I am comfortable in saying that another peak will happen in 2013 and possibly last into 2014.'

There is also a pattern of escalating threats whenever South Korea gets a new leader. While many observers dismiss the rhetoric as bluster, others warn of "the tyranny of low expectations" when it comes to understanding North Korea, because there have been a number of serious regional confrontations.

"If you follow North Korean media you constantly see bellicose language directed against the US and South Korea and occasionally Japan is thrown in there, and it's hard to know what to take seriously. But then when you look at occasions where something really did happen, such as the artillery attack on a South Korean island in 2010, you see there were very clear warnings," Professor John Delury at South Korea's Yonsei university told the BBC.

The North consistently warned that military exercises being conducted in the area would spark a retaliation. Mr Delury argues that misreading Pyongyang's intentions and misunderstanding its capabilities has kept the US and South Korea stuck in a North Korean quagmire. The latest series of threats are being seen as "bluff" because the North's leaders know a nuclear attack would be suicidal and impractical, given the North's rudimentary missile programme.

“As a bipartisan group of former senators stated in their March 1 amicus brief to the Supreme Court, many supporters of the bill known as DOMA believed that its passage “would defuse a movement to enact a constitutional amendment banning gay marriage, which would have ended the debate for a generation or more.” It was under these circumstances that DOMA came to my desk, opposed by only 81 of the 535 members of Congress.

On March 27, DOMA will come before the Supreme Court, and the justices must decide whether it is consistent with the principles of a nation that honors freedom, equality and justice above all, and is therefore constitutional. As the president who signed the act into law, I have come to believe that DOMA is contrary to those principles and, in fact, incompatible with our Constitution. Because Section 3 of the act defines marriage as being between a man and a woman, same-sex couples who are legally married in nine states and the District of Columbia are denied the benefits of more than a thousand federal statutes and programs available to other married couples.

When I signed the bill, I included a statement with the admonition that “enactment of this legislation should not, despite the fierce and at times divisive rhetoric surrounding it, be understood to provide an excuse for discrimination.” Reading those words today, I know now that, even worse than providing an excuse for discrimination, the law is itself discriminatory. It should be overturned.

We have yet to celebrate the centennial of the 19th Amendment, but a society that denied women the vote would seem to us now not unusual or old-fashioned but alien. I believe that in 2013 DOMA and opposition to marriage equality are vestiges of just such an unfamiliar society.”

Earlier, Pyongyang said it had a right to carry out a pre-emptive nuclear strike and was pulling out of the armistice that ended the Korean War. The US said "extreme rhetoric" was not unusual for Pyongyang.

China, which is the North's only major ally, called for both North and South to show restraint and to continue talking. Beijing rarely criticises its ally, but has criticised the North's nuclear tests and has given support to the UN's sanctions.

South Korea's President Park Geun-hye said the current security situation was "very grave" but that she would "deal strongly" with provocation from the North. She also said she was ready to talk to Pyongyang if it "comes out on the path toward change".

The threat from the North Koreans came ahead of a unanimous vote in the UN Security Council approving its toughest sanctions yet on the North in response to an atomic test last month.

North Korea has now conducted three nuclear tests. In the past year, it has made strides toward its goal of having a nuclear weapon that could threaten the US although experts doubt it yet has the capability to hit the US with a ballistic missile or miniaturize a nuclear device to mount on such a missile.

However, the North possesses hundreds of shorter-range missiles that could hit US bases in Japan and South Korea, said Victor Cha, Korea chair at the Center for Strategic and International Studies think tank. It is difficult to know how capable US missile defense is, should it be required.

Instead of the originally-expected $250 million cut, US foreign aid to Israel will drop by $150 million, Washington sources allegedly told Finance Minister Yuval Steinitz. The sources said the cut was unavoidable, given the across-the-board slash, down from eight percent to five percent, in the nation’s budget.

Numerous Israeli firms that provide products and services to the US government, including those in the military industries, are expected to be affected by the reduction. However, newly-confirmed Secretary of Defense Chuck Hagel said Tuesday that any cuts would not affect US funding for Israel’s rocket and missile defense programs.

“Secretary Hagel expressed his strong commitment to Israel’s security, including maintaining Israel’s qualitative military edge and continued US support for missile and rocket defense systems, in spite of fiscal constraints,” Pentagon spokesman George Little said in a statement. A separate defense official, who spoke on condition of anonymity, said that Hagel “is committed to working with members of Congress to ensure that there is no interruption of funding for Iron Dome, Arrow, and David’s Sling rocket and missile defense systems, despite the fiscal uncertainly due to Congressional inaction.”

He spent more than three years investigating the science of junk food for his new book, Salt, Sugar, Fat: How the Food Giants Hooked Us. His findings make unpalatable reading. Moss uncovered numerous tricks of the trade - from changing the physical shape of salt to altering the chemical make-up of sugar and even giving crisps a more noisy crunch - all of which can tempt us into buying foods that are often extremely unhealthy.

And, after talking to executives and scientists at multi-nationals such as Pepsi, Kraft, Unilever, Mars and Kellogg, he discovered that at the heart of corporate strategies is that unholy trinity of salt, sugar and fat. Moss found just how far the industry will go to harness their seductive powers. Results from MRI-scanning studies are used by companies to study the sensory power of food - for example, how sugar lights up our brains the same way it does after someone has taken cocaine.

Manufacturers want to achieve a perfect link between food and joy in consumers’ brains to make us come back for more, so the industry has become obsessed with hitting this “bliss point”. With sugar, the bliss point is the precise amount of sweetness that makes food and drink most enjoyable. It means scientifically testing thousands of customers’ preferences, constructing intricate mathematical formulae, and surveying populations for cultural and demographic differences.

Junk foods at fast food restaurants as well as processed foods at grocery retailers represent the largest sources of sodium intake from refined salts. Many low-fat foods rely on salt - and lots of it - for their flavor. One packet of KFC’s Marzetti Light Italian Dressing might only have 15 calories and 0.5 grams fat, but it also has 510 mg sodium-about 1.5 times as much as one Original Recipe chicken drumstick. Feel like you’re having too much of a good thing? You probably are.

Bread is the Number 1 source of refined salt consumption in the American diet, according to the Centers for Disease Control and Prevention. Just one 6-inch Roasted Garlic loaf from Subway - just the bread, no meat, no cheeses, no nothing - has 1,260 mg sodium, about as much as 14 strips of bacon.

Dr Hendel believes too few minerals, rather than too much salt, may be to blame for health problems. It's a view that is echoed by other academics such as David McCarron, of Oregon Health Sciences University in the US. He says salt has always been part of the human diet, but what has changed is the mineral content of our food. Instead of eating food high in minerals, such as nuts, fruit and vegetables, people are filling themselves up with "mineral empty" processed food and fizzy drinks.

“We must leave the austerity cage,” he told leaders of his Democrat Party (Pd), responding to Italy’s electoral earthquake by tearing up his pre-election programme. “A change of course is absolutely necessary given that five years of austerity and attacks on workers have pushed up public debt levels across Europe,” he said.

“The vicious circle between belt-tightening and recession is putting representative government at risk and making it impossible to govern. The immediate emergency is the real economy and joblessness,” he said. The pledge puts Mr Bersani on a collision course with the ECB, which is constrained from helping to shore up the Italian bond market unless Rome complies with Europe’s austerity agenda.

“Italian voters may have effectively voted away the ECB safety net,” said Christian Schulz from Berenberg Bank. The central bank cannot activate its bond purchase programme (OMT) unless Italy requests a rescue from the EMU bail-out fund, and that in turn requires a vote in Germany’s Bundestag. “The ECB cannot – and will not want to – do anything to help Italy after the inconclusive election result, even if borrowing costs spiral out of control,” he said.

Mr Bersani said Italy should mobilize its EU voting weight to push for an EU-wide change of course. He has natural allies in Paris. French finance minister Pierre Moscovici warned EMU colleagues on Monday that current policies “risk a loss of social and political confidence across Europe. We must not pile austerity on top of recession”.

French officials are deeply alarmed by the relentless upward rise in France’s unemployment rate to 10.6 percent, or 26.9 percent for youth. President Francois Hollande’s popularity ratings have crashed from 55 percent to 30 percent since his election in May, the fastest decline ever recorded for a French leader. Italy, France, and Spain toyed with a Latin bloc alliance last year to confront Germany over EMU’s contractionary policy mix, but the initiative faded.

International media describe Grillo as a comic, which on one level he is, but the man who jointly created and leads the party that in just three years has become the largest in Italy is much more than that. Behind his tirades against the political and business elite is a shrewd mind, a hugely influential alter ego and the desire to win complete power in the euro zone's third largest economy.

"The left and right will govern together on the ruins they've created, it will last a year at most, then our movement will change the world," Grillo said after his party's triumphant performance in last week's election. "Unless the other parties change their leaders and somehow get back in touch with ordinary people he can certainly keep on growing," said Elisabetta Gualmini, politics professor at Bologna University and a close observer of Grillo's movement.

Grillo and Casaleggio understood Italians' need for something different. And everything about 5-Star is different. It is the only party that refuses state financing and its elected representatives have all voluntarily slashed their salaries. Its members never appear on television talk shows, it communicates almost exclusively through Grillo's blog (www.beppegrillo.it), and it refuses to form alliances with other parties.

Grillo aims to appeal to left and right. He attacks the old "zombie" parties and business fat cats but also the trade unions who he says no longer represent workers' interests. And it's not all vitriol. He also offers the positive message that politics can be clean and different, constantly citing the movement's local councilors who have given up most of their salaries to provide cheap credit to small businesses.