Heavy metal space rock
The detection of the heavy metals iron (Fe) and nickel (Ni) in the fuzzy atmosphere of a comet are illustrated in this image, which features the spectrum of light of C/2016 R2 (PANSTARRS) on the top left superimposed to a real image of the comet taken with the SPECULOOS telescope at ESO’s Paranal Observatory. Credit: ESO/L. Calçada, SPECULOOS Team/E. Jehin, Manfroid et al.
For the first time, astronomers have detected traces of heavy metals in the atmospheres of comets – both those whizzing through our Solar System and those from interstellar space.
Scientists have long known that the dusty, rocky interiors of comets harbour solid forms of heavy metals. But these metals have only previously been observed in hot environments, like evaporating comets soaring to close too the Sun or ultra-hot exoplanet atmospheres.