New analysis of Mercury backs up Vonnegut. An awfully pretty image, from the MESSENGER spacecraft, shows the moon-like planet. Unlike the moon, however, new analysis suggests that the smooth plains were surfaced mainly by volcanic action, rather than by meteoric impacts and the dusting of detritus. Its magnetic field too seems to indicate immense internal activity.

Accordingly, Kurt Vonnegut's fantasy that Mercury has a continuous song, or vibration, gains credence. His kite-shaped harmonium creatures, if really hanging out down in caves, would have plenty of rumblings on which to feed.