Thursday, April 25, 2013

V is for Variable Star

As I mentioned in an earlier post, parallax is a method of measuring the distance of nearby stars. The next step on the cosmic distance ladder is a kind of star known as a Cepheid Variable.  This video explains what these stars are and how they're used to determine cosmic distance.  There's also a little bit about the history of women in astronomy, which I think is cool.  Enjoy!


  1. Cool.

    I love how Astronomers have figured all this stuff out! Of course they still look up at the sky and think how much more there is to know!

    Tim Brannan
    The Other Side and The Witch
    Red Sonja: She-Devil with a Sword
    The Freedom of Nonbelief

  2. Recently I've talked to my 8 yr old son about distances in the universe. We talk about light years, but that concept is a bit hard to understand for that age. In doing that, we end up talking about the speed of sound too. Which is also hard to understand.

    But with that we have an example of how it works when he's seen the Navy's Blue Angels fly. And of course when they streak over your head, you see them before you hear the sound. Kinda of disappointed they're grounded because of the whole government sequestration thing. One more thing that is hard for a kid to understand.

  3. Astronomy requires so much patience. Detailed records are a must in order to track the movements that seem not to be happening to a casual observer.

    Blogging from A to Z
    Twitter: @AprilA2Z

  4. I'll have to book mark this and watch it later, the video is taking too long to load.. it's just up my street as a lay person interested in science. Thank you so much!

    Susan Scott's Soul Stuff

  5. Hi. New member here. An amazing site! My husband and I share a long time lay interest in astronomy. We've watched a lot of 'nerdy' star documentary on PBS over the years:) Check out my post under 'seasons' label: Winter of the Stars. We walked every night when Hale-Bopp's comet appeared.