Scientists prepare to observe rare alignment of Venus
For weeks, astronomers have been putting out the alert: Now or never! See it while you can! Last chance in more than a lifetime! Before sunset Tuesday, amateurs and professionals around the world will watch as the planet Venus appears in silhouette -- a tiny black spot that will slowly traverse the sun’s face. The transit of Venus -- which will be visible from 6:03 p.m. until the sun sets in Boston -- is an exceedingly rare event.