Cosmic distances is topic at next BPAA planetarium show

Published 3:30 pm Thursday, March 9, 2017

The planetarium show “Climbing the Cosmic Distance Ladder” comes to the Edwin E. Ritchie Observatory at 7:30 p.m. Saturday, March 11.

When astronomers say some object is so many million light years away, how do they know that? Astronomer Steve Ruhl will climb the cosmic distance ladder and show how astronomers, past and present, determine distances to objects.

BPAstro Kids will be “Imaging the Universe” with Dr. Erica at 4 and 5 p.m.

If the sky is clear, astronomers will be on hand with telescopes for public star gazing afterward.

The show is free to members of the Battle Point Astronomical Association; $2 donation suggested for nonmembers, $5 for families.

The BPAA is a nonprofit amateur astronomy organization that operates the Ritchie Observatory and John H. Rudolph Planetarium in the Helix House at Battle Point Park.