Soldiers Delight Star Party Lecture - August 17

The Cosmic Distance Scale: A Journey Across the Universe

Ever wondered how astronomers determine the distances to the planets, stars and galaxies? Then why not stop by the Soldiers Delight Visitor Center at 5100 Deer Park Rd., Owings Mills, MD 21117, August 17, at 8:00pm. I am the host for these events which are scheduled for the third Saturday of each month - April through October. Each month I present a 'down-to-earth' presentation based on some specific area of Astronomy and Space. Presentations can be fairly detailed (to keep the adults interested), but I always try to make sure everyone learns something. And yes, they are kid-friendly, and frequently include a hands-on fun project (to keep the younger crowd happy too). As a bonus, if the sky is clear, telescopes are usually set-up to observe something after the lecture. 

August's Topic:  "The Cosmic Distance Scale: A Journey Across the Universe"

Join us for an enlightening voyage through the vastness of space! Our stellar navigators will unravel the secrets of cosmic distances, allowing us to piece together the fabric of the universe. 

We’ll start close to home, measuring the astronomical unit (AU) within our Solar System. Then, step by step, we’ll extend our reach into the cosmic expanse. Learn how astronomers use parallax—the apparent shift in a star’s position—to measure distances to nearby stars. Ground-based parallaxes reveal secrets up to 100 parsecs away, while the Hipparcos mission extends our cosmic tape measure to 1000 parsecs.

Sometimes, we can’t rely on geometry alone. Enter the “standard candles”—objects whose luminosities we know. By comparing their apparent brightness to their true luminosity, we unlock distances to galaxies and quasars. It’s like pulling ourselves up by cosmic bootstraps!

These distances form the foundation for understanding our universe’s past, present, and future. From the expanding cosmos to the birth of stars, we’ll explore it all.

Buckle up, stargazers! Reserve your seat for this cosmic odyssey.

All programs are Rain or Shine. Time machines will be provided by the Westminster Astronomy Club.

Specific details can be found at Night Sky Network.