A new kind of cosmic flash may reveal something never seen before: the birth of a black hole.

Ringed by mountains and capped by a temperature inversion that traps bad air, Los Angeles has had bouts of smog since the turn of the 20th century. An outbreak in 1903 rendered the skies so dark that many people mistook it for a solar eclipse. Angelenos might now be living in a state of perpetual midnight—assuming we could live here at all—were it not for the work of Caltech Professor of Bio-organic Chemistry Arie Jan Haagen-Smit. How he did it is told here largely in his own words, excerpted from Caltech's Engineering & Science magazine between 1950 and 1962. (See "Related Links" for the original articles.)

Catherine Bingchan Xie, a senior bioengineering major and English minor at Caltech, has been selected to receive a Gates Cambridge Scholarship, which will fund her graduate studies at the Universi

The mission: travel to one of Mars's two moons, explore its surface, collect some rocks, and return to Earth in one piece. Now plan it—in five days.