Science enthusiasts are hoping to get a glimpse of a comet that’s supposed to be the brightest of 2025, but they may be out ...

Comets develop the spectacular long tails that they are known for by approaching the Sun. When they get too close, their icy volatile materials begin to sublimate away, carrying along clouds of dust.

Whistling and moaning, a 50-mile-an-hour (80-kilometer-an-hour) wind whipped among the telescope domes atop Kitt Peak. Just a few feet below, turning gray in the dusk, slid a river of clouds that ...