Need to know:
Seoul has warned that it's preparing to shoot down a North Korean rocket if it violates South Korean territory, as world leaders gather there for an international nuclear security summit.
Worries about next month's launch — which Washington and Seoul say is meant to test delivery systems for long-range missiles that could carry nuclear weapons, but which Pyongyang claims are part of its peaceful space program — have overshadowed the talks.
US President Barack Obama, one of 54 world leaders in attendance, earlier appealed directly to North Korea, and also Iran, to help the world sleep easier at night by renouncing all claims to nuclear arms. Just imagine "a world without nuclear weapons," Obama pleaded.
North Korea reportedly responded by moving its rocket to the launch pad.
Want to know:
Senegal is waking up to a new era this morning, after President Abdoulaye Wade conceded election defeat to challenger Macky Sall.
The opposition candidate's supporters have been celebrating since late last night, when unofficial results gave Sall a commanding lead in the presidential run-off vote.
Wade, 85, who has ruled the West African nation for 12 years, phoned his rival and former protégé to congratulate him on his victory – raising hopes that the transition will be smooth.
Dull but important:
President Obama may be relieved to be out in Seoul today, as the US Supreme Court prepares to hear arguments over the constitutionality of his administration's flagship health care reform.
The court will hear six hours of arguments over three days about the constitutionality of the Patient Protection and Affordable Care Act (PPACA), passed in 2010 and now facing a legal challenge from 26 states.
US voters have already made up their minds, according to a poll last month: three-quarters of them would tell you that "ObamaCare" is unconstitutional in requiring every American to have health insurance.
A ruling is expected in June, smack-bang in the middle of election season.
Almost every American or European university has a center for Middle Eastern, Islamic or Arab studies. But for a long time, there was not a single center in the Middle East with a focus on the West.
One Saudi scholar decided to change that, with the creation of the Western Studies Institute in Riyadh. Its mission, the founder says, is to build bridges between the Arab and Western worlds, starting with Saudi Arabia and the United States.
That's a more ambitious task than you might think, in a country where some insist that Muslims should not interact too much with foreigners or people of different religions lest it weaken their own Islamic faith.
Strange but true:
Deep-sea explorer and director of watery-death movies James Cameron has become the first person to dive solo to the Earth's deepest underwater point.
The man behind Titanic and The Abyss plunged to the bottom of the Pacific Ocean's Mariana Trench, some seven miles below sea level, early this morning. He's since returned to the surface, brandishing a clutch of scientific samples, photographs and 3D video footage.