May 18, 2012 Galaxies in the Young Cosmos The universe was born about 13.7 billion years ago in the big bang. The Sun and its system of planets formed about five billion years ago. What happened, then, during that long, intervening stretch of nearly nine billion years?   Read More...

May 11, 2012 Capturing Planets The discovery of planets around other stars has led to the realization that alien solar systems often have bizarre features - at least they seem bizarre to us because they were so unexpected.  Read More...

May 04, 2012 Diagnosing a Black Hole Flare Black holes can come in a wide range of masses. Some, with only about one solar mass, result from the supernova death of a massive star, while those at the center of galaxies (called supermassive black holes) have millions or even billions of solar masses.   Read More...