Bern scientists stuck their collective necks out and suggested that Earth might be the resting ground to as much as 16 quadrillion tons of Mercury's ejected rock-wow, that's a lot of Mercury on Mother Earth. However, this idea will remain a scientific challenge to prove, at least until geological samples from Mercury's surface are collected and returned to Earth for study. Next, the rocks have to be chemically matched alongside suspected Mercurian meteorites to ultimately prove theory as fact.
What's in the Sky-Get a fleeting glimpse of the planet Mercury low in the western sky around 8 p.m., Saturday, Aug. 22 (see accompanying sky map).
Louis Varricchio, M.Sc., lives in Vermont. He is a former NASA senior science writer and a current member of the NASA/JPL Solar System Ambassador program. He is also a member of the Association of Lunar and Planetary Observers.