According to NASA, transits of Venus across the disk of the Sun are among the rarest of planetary alignments.  The last time it occurred, in 2004, I happened upon some wonderful pinhole viewing boxes set up in a Paris park.  (The 2004 transit allowed full visibility throughout Europe, where I happened to be living at the time.)

This year the viewing “sweet spot” happens to be the open Pacific, so most of us will get either partial views, or in some cases, none at all.

So, for those of us neither lucky enough to stumble upon a viewing box or to live somewhere in the Pacific Ocean, NASA’s live stream comes to the rescue.