The recommendation is certain to add a level of complexity to one of the most vexing debates in medicine: how men older than 50 should deal with the threat of prostate cancer. Each year, about 200,000 Americans are diagnosed with the disease, and about 29,000 die. A host of complications and controversies attend nearly every dimension of the disease, from prevention to diagnosis to treatment.

Over the next three nights, skywatchers can expect their best views yet of Comet Lulin, an odd, greenish backward-flying comet that's "zipping by Earth this month, as it takes its only trip toward the sun from the farthest edges of the solar system." The Chicago Tribune reports that Comet Lulin makes its closest approach to Earth — some 38 million miles away — on Tuesday, Feb. 24.

but the clamshell-like housing that protects the satellite during its rise through the atmosphere failed to open and break away from the rocket’s final stage. Burdened with added weight, the engine couldn’t deliver enough push to loft the satellite to orbit. It fell back to Earth over the Southern Ocean.