Comets crumble

The brightest comet of the past three years has blown itself to bits. Mark
Kidger of the Astrophysics Institute of the Canaries used the 1-metre Jacobus
Kapteyn Telescope on La Palma to track comet LINEAR as it passed by the Sun.
Between 24 and 25 July, the teardrop-shaped cloud around the comet’s icy nucleus
stretched out and became uniformly bright. On subsequent evenings, the cloud
grew bigger and dimmer, indicating that the nucleus had completely
disintegrated. “If LINEAR is typical,” Kidger says, “it turns out that the
nucleus is extraordinarily fragile.”