Pioneering

The Pioneer space probes are slowing down, and we didn't know why for quite some time. This article seems to indicate the mystery is solved (hint: it wasn't anything too mysterious). Along the way there are many interesting and nerdy nuggets of info like what those things on the end of those poles are (radioactive power sources). Anyway, the story ends with a plea to make sure raw experimental data is kept readable though the years; one poor guy had to get transmission data off some mouldy tape that was found "under the stairs" at the JPL.