Published online 17 October 2007 | Nature 449, 769 (2007) | doi:10.1038/449769d

News in Brief

NASA/JOHNS HOPKINS UNIV./SOUTHWEST RES. INST.

Astronomers have witnessed a spectacular eruption on Io, the fiery moon of Jupiter. NASA's New Horizons probe snapped pictures (right) of a volcanic plume 350 kilometres high — 40 times the height of Mount Everest — when the probe passed by Jupiter in February and March on its way to Pluto.

Results from the fly-by were presented at the annual meeting of the American Astronomical Society's Division for Planetary Sciences on 9 October in Florida, and also appear as papers in the 12 October issue of Science.

Scientists were surprised to find that Jupiter's weather was abnormally quiescent. But Io — kneaded by Jupiter's gravity into constant volcanic upheaval — didn't disappoint. Scientists took 39 pictures of the Tvashtar volcano over 8 days, as an orange, sulphur-rich plume rocketed out at speeds up to 700 metres per second.