The patient accretion of knowledge, the focusing of all one’s energies on some problem in history or science, the dogged pursuit of excellence of whatever kind these are right and proper ideals for life. ~Michael Dirda Nothing can escape from a black hole, not even light. This is why we call them “black.” One would imagine, then, that black holes are black invisible menaces, lurking out in the depths of space. Surprisingly, though, black holes glow. The cover image shows a radio photograph of the center of the Milky Way. The center glow, Sagittarius A, is partly due to