The dramatic appearance of Halley's comet in the night sky has been observed and recorded by astronomers since 240 BC.

The dramatic appearance of Halley's comet in the night sky has been observed and recorded by astronomers since 240 BC.

Europe’s Rosetta spacecraft is en route to intercept a comet– and to make history. In 2014, Rosetta will enter orbit around comet 67P/Churyumov-Gerasimenkoand land a probe on it, two firsts.

New findings from NEOWISE, the asteroid- and comet-hunting portion of NASA's Wide-field Infrared Survey Explorer mission, show that comet Hartley 2 leaves a pebbly trail as it laps the sun, dotted with grains as big as golf balls.

Twenty-five years ago, ESA's Giotto spacecraft made its mark in deep space.