Reality Checks: Groundbreaking Programmer, Scientists and the Public, Male Birth Control, and the White Noise of Black Holes

Studies of one of the galaxy's most active black-hole binaries reveal a dramatic change that will help scientists better understand how these systems expel fast-moving particle jets. GX 339-4, illustrated here, is among the most dynamic binaries in the sky, with four major outbursts in the past seven years. In the system, an evolved star no more massive than the sun orbits a black hole estimated at 10 solar masses. (12/10/2009) Credit: ESO/L. Calçada