Evan Osnos

In the final years of his life, when former Communist Party Chief Zhao Ziyang lived under house arrest, in Beijing, his aging friends resorted to donning white doctors' coats in order to slip past the guards stationed outside his home.

The overwhelming bulk of the cosmos is deathly quiet. But here and there - on worlds where matter is thick and conditions are right - noises are commonplace. And in some cases, these noisy worlds may ring with the sounds of life - the bleats and bellows of creatures we have never seen, but may someday discover.

What do cells do when they see a broken piece of DNA? Cells don't like such breaks. They'll do pretty much anything they can to fix things up. If a chromosome is broken, the cells will repair the break using an intact chromosome.