After a quiet summer, bird flu cases are rising again. Scientists expected the development, but what happens next is still uncertain

Cliff-rappelling scientists uncovered a crossbow bolt, part of a slingshot and 25 shoes in ancient vulture nesting sites

A comet’s brightness depends on how it’s made, how and when we see it, and even a bit of unpredictable luck

Despite the widespread use of medication during pregnancy, a lack of clinical research leaves patients and doctors navigating treatment with danger...