November 24, 2017

How Far? Measuring Astronomical Distances.

But a nearby stepping stone; our humble moon. (Photo by Author).

   You hear it at every star party. It’s probably the next biggest question right behind “is there life out there,” and “can you really see the flag the astronauts left on the moon with that thing?” Just how do we know how far away things are in the universe? After all, men have never ventured beyond the Moon; and it has only been in the past half century that we have sent embassaries on trajectories that will escape our solar system… just how do we measure these enormous distances with any confidence?
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