>> larry: it's a night you never forget. i had a feeling that night that this show would make it. when you get down to it, it's who, what, when, where why. i'm there to ask questions. do my best. we want you to help us pick our top "larry king live" moments of the past 25 years. just go to cnn.com/larryking. have fun watching all the clips. and rank your top five. we'll reveal them during my silver anniversary week, beginning may 31st. now, let's check in with sanjay gupta hosting "a.c. 360" tonight. what's our lead, sanjay? >> a deadly blast is about to become an environmental disaster. that oil slick in the gulf of mexico is approaching land. it's also much worse than previously estimated. by one account, this could be nearly twice as bad as the exxon