Modern science moves so fast that it’s easy to reflect on the changes of the past week, let alone the past decade or century. But astronomy is one notable exception to this rule. Arguably no other scientific endeavor is so full of history.
For this reason, astronomical events like the transit of Venus present a rare chance to compare what we can see today with what our forebears saw hundreds of years ago, both literally and in their world views. This is something you can’t really do with genetics, for instance.