As many of you space junkies know our Pioneer spacecraft have exhibited an "anomaly" with regard to their expected trajectories during their outward solar system journey and ideas as to the cause have ranged from the mundane to calls for reexamining our understanding of gravity and/or physics.
Anyway,
Sky & Telescope.com emails me a newsletter every week or so and today's contained a news item about Slava Turyshev of the Jet Propulsion Laboratory proposing that possible "weathering" of the surfaces of the Pioneer spacecraft is causing uneven heat emission, which in turn accounts for the Pioneer's slower than expected speed. The entire piece can be read at the Sky & Telescope website where this story is currently on their main page or by clicking
here.
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